DIABETES MELLITUS

R. BISIGNANI · 2026 · Case ID: A26033547

MIXED

Summary

The Veteran, who served in the U.S. Army from November 1967 to November 1969, appeals the denial of service connection for diabetes mellitus type II, hypertension, obstructive sleep apnea, and erectile dysfunction. The Veteran also appeals the remand of claims for arteriosclerotic heart disease (coronary artery disease) and entitlement to TDIU. The Veteran contends that his diabetes, hypertension, and sleep apnea are related to in-service herbicide exposure, specifically at Fort Chaffee, Arkansas. The Board found no evidence to verify herbicide exposure at Fort Chaffee during the relevant periods, nor did the service records show the Veteran was assigned there during those times. Furthermore, the Veteran's service treatment records were silent for diabetes, hypertension, sleep apnea, and erectile dysfunction. VA TERA opinions in March 2023 and January 2025 found the Veteran's diabetes, hypertension, and sleep apnea less likely than not related to toxic exposure or service-connected tinnitus. The Board denied direct service connection for these conditions, finding no continuity of symptomatology and that the weight of the evidence was against the claims. For sleep apnea and erectile dysfunction, the Board also denied secondary service connection, noting the lack of medical nexus to service-connected tinnitus or diabetes. The Board remanded the claims for coronary artery disease and TDIU, citing insufficient development regarding the Veteran's in-service chest complaints and the intertwined nature of these issues.

Rationale

No verifiable herbicide exposure at Fort Chaffee; Service treatment records silent for diabetes; VA TERA opinion found less likely than not related to toxic exposure; No continuity of symptomatology

Service Branch

ARMY

Special Benefit

TDIU

Docket No.

251124-618772

Full Decision Text

Citation Nr: A26033547
Decision Date: 04/10/26 Archive Date: 04/10/26

DOCKET NO. 251124-618772
DATE: April 10, 2026

ORDER

Entitlement to service connection for diabetes mellitus type II is denied.

Entitlement to service connection for hypertension is denied.

Entitlement to service connection for obstructive sleep apnea is denied.

Entitlement to service connection for erectile dysfunction is denied.

REMANDED

Entitlement to service connection for arteriosclerotic heart disease (coronary artery disease) is remanded.

Entitlement to a total disability rating based on individual unemployability (TDIU) is remanded.

FINDINGS OF FACT

1. The Veteran's exposure to Agent Orange during service has not been demonstrated.

2. Diabetes mellitus and hypertension were not shown in service, did not manifest to a compensable degree within one year of service separation, and is not otherwise related to service.

3. An obstructive sleep apnea disability is not related to service, and is not caused or aggravated by a service-connected disability.

4. The Veteran's erectile dysfunction disability is not related to service, and is not caused or aggravated by a service-connected disability.

CONCLUSIONS OF LAW

1. The criteria for entitlement to service connection for a diabetes mellitus disability to include as due to herbicide agent exposure, and other toxic exposure have not been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309.2; 38 C.F.R. § 3.303 (2021).

2. The criteria for entitlement to service connection for a hypertension disability to include as due to herbicide agent exposure, and other toxic exposure have not been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309.2; 38 C.F.R. § 3.303 (2021).

3. Service connection for an obstructive sleep apnea disability, to include as secondary to a service-connected disability, is not warranted. 38 U.S.C. §§ 1110, 1131 (2012) 38 C.F.R. §§ 3.303, 3.304, 3.310 (2021).

4. Service connection for an erectile dysfunction, to include as secondary to a service-connected disability, is not warranted. 38 U.S.C. §§ 1110, 1131 (2012) 38 C.F.R. §§ 3.303, 3.304, 3.310, 3.317 (2021).

REASONS AND BASES FOR FINDINGS AND CONCLUSIONS

The Veteran served on active duty in the United States Army from November 1967 to November 1969 with additional service in the National Guard.

With exception to the sleep apnea claim, the claims on appeal were initially denied in an October 2022 rating decision. The agency of original jurisdiction (AOJ) then issued a rating decision in March 2023, based on a finding that the prior October 2022 rating decision had been issued prematurely.

The Veteran's claim for service connection for sleep apnea was initially denied in an August 2023 rating decision.

In May 2023, the Veteran submitted a VA Form 20-0996, Decision Review Request: Higher-Level Review (HLR), and requested review of the March 2023 decision. In September 2023, the AOJ issued a HLR decision, which considered the evidence of record at the time of the prior March 2023 decision.

In October 2024, the AOJ issued a rating decision which addressed the claims on appeal with exception to the sleep apnea claim, indicating that a special review of the Veteran's file was mandated.

In September 2024, the Veteran submitted a VA Form 20-0995, Decision Review Request: Supplemental Claim, and requested readjudication of the claims on appeal. In January 2025, the AOJ issued the supplemental claim decision on appeal, which denied the claims on the merits.

In June 2025, the Board remanded these issues for additional development.

In the October 2025 rating decision on appeal, the RO again denied the Veteran's claims.

In the November 2025 VA Form 10182, Decision Review Request: Board Appeal (Notice of Disagreement), the Veteran elected the Evidence Submission docket.

Therefore, the Board may only consider the evidence of record at the time of the
.

In June 2025, the Board remanded these issues for additional development.

In the October 2025 rating decision on appeal, the RO again denied the Veteran's claims.

In the November 2025 VA Form 10182, Decision Review Request: Board Appeal (Notice of Disagreement), the Veteran elected the Evidence Submission docket.

Therefore, the Board may only consider the evidence of record at the time of the October 2025 agency of original jurisdiction (AOJ) decision on appeal, as well as any evidence submitted by the Veteran [or representative] with, or within 90 days from receipt of, the VA Form 10182. 38 C.F.R. § 20.303. If evidence was submitted either (1) during the period after the AOJ issued the decision on appeal and prior to the date the Board received the VA Form 10182, or (2) more than 90 days following the date the Board received the VA Form 10182, the Board did not consider it in its decision. 38 C.F.R. §§ 20.300, 20.303, 20.801.

If the Veteran would like VA to consider any evidence that was submitted that the Board could not consider, the Veteran may file a Supplemental Claim (VA Form 20-0995) and submit or identify this evidence. 38 C.F.R. § 3.2501. If the evidence is new and relevant, VA will issue another decision on the claim[s], considering the new evidence in addition to the evidence previously considered. Id. Specific instructions for filing a Supplemental Claim are included with this decision.

However, because the Board is remanding the claims of service connection for coronary artery disease and entitlement to a TDIU, any evidence the Board could not consider will be considered by the AOJ in the adjudication of those claims. 38 C.F.R. § 3.103(c)(2)(ii).

Service Connection

Laws and Regulations

Service connection will be granted if the evidence demonstrates that a current disability resulted from an injury or disease incurred in or aggravated by active military service. 38 U.S.C. §§ 1110, 1131; 38 C.F.R. § 3.303(a).

To establish a right to compensation for a present disability, a Veteran must show: "(1) the existence of a present disability; (2) in-service incurrence or aggravation of a disease or injury; and (3) a causal relationship between the present disability and the disease or injury incurred or aggravated during service." Davidson v. Shinseki, 581 F.3d 1313, 1315-16 (Fed. Cir. 2009); Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004).

Certain diseases, such as diabetes and hypertension, may be presumed to have been incurred in service when manifest to a compensable degree within one year of discharge from active duty. 38 U.S.C. § 1112 (2012); 38 C.F.R. §§ 3.307, 3.309 (2021).

Under 38 C.F.R. § 3.303(b), an alternative method of establishing the second and third Shedden for certain chronic disabilities such as diabetes and hypertension is through a demonstration of continuity of symptomatology.

In relevant part, 38 U.S.C. § 1154(a) requires that the VA give "due consideration" to "all pertinent medical and lay evidence" in evaluating a claim to disability or death benefits. Lay evidence can be competent and sufficient to establish a diagnosis of a condition when (1) a layperson is competent to identify the medical condition, (2) the layperson is reporting a contemporaneous medical diagnosis, or (3) lay testimony describing symptoms at the time supports a later diagnosis by a medical professional." Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed.Cir.2007). In fact, competent medical evidence is not necessarily required when the determinative issue involves either medical etiology or a medical diagnosis. Id. at 1376-77; see also Buchanan v. Nicholson, 451 F.3d 1331, 1337 (Fed. Cir. 2006); Davidson v. Shinseki, 581 F.3d 1313 (Fed. Cir. 2009).

Once
the layperson is reporting a contemporaneous medical diagnosis, or (3) lay testimony describing symptoms at the time supports a later diagnosis by a medical professional." Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed.Cir.2007). In fact, competent medical evidence is not necessarily required when the determinative issue involves either medical etiology or a medical diagnosis. Id. at 1376-77; see also Buchanan v. Nicholson, 451 F.3d 1331, 1337 (Fed. Cir. 2006); Davidson v. Shinseki, 581 F.3d 1313 (Fed. Cir. 2009).

Once evidence is determined to be competent, the Board must determine whether such evidence is also credible. See Layno, supra (distinguishing between competency ("a legal concept determining whether testimony may be heard and considered") and credibility ("a factual determination going to the probative value of the evidence to be made after the evidence has been admitted").

When there is an approximate balance of positive and negative evidence regarding any issue material to the determination of a matter, the VA shall give the benefit of the doubt to the claimant. 38 U.S.C. § 5107(b).

Under 38 C.F.R. § 3.310(a), service connection may be granted for disability that is proximately due to or the result of a service- connected disease or injury. Such permits a grant of service connection not only for disability caused by a service-connected disability, but for the degree of disability resulting from aggravation to a nonservice- connected disability by a service- connected disability. Id. See also Allen v. Brown, 7 Vet. App. 439, 448 (1995); 38 C.F.R. § 3.310(b).

In order to prevail on the issue of entitlement to secondary service connection, there must be (1) evidence of a current disability; (2) evidence of a service-connected disability; and (3) nexus evidence establishing a connection between the service-connected disability and the current disability. See Wallin v. West, 11 Vet. App. 509, 512 (1998).

The term "Veteran" is defined in 38 U.S.C. § 101(2) (West 2002) as "a person who served in the active military, naval, or air service, and who was discharged or released therefrom under conditions other than dishonorable." The term "active military, naval, or air service" includes active duty, and "any period of active duty for training during which the individual concerned was disabled or died from a disease or injury incurred or aggravated in line of duty, and any period of inactive duty training during which the individual concerned was disabled or died from an injury incurred or aggravated in line of duty." 38 U.S.C. § 101(24) (West 2002); 38 C.F.R. § 3.6(a) (2012); see Biggins v. Derwinski, 1 Vet. App. 474, 477-478 (1991).

Active duty for training (ACDUTRA) is defined, in part, as "full-time duty under sections 316, 502, 503, 504, or 505 of title 32 [U. S. Code] or the prior corresponding provisions of law." 38 U.S.C. § 101(22) (West 2002); 38 C.F.R. § 3.6(c) (2017). The term inactive duty training (INACDUTRA) is defined, in part, as duty, other than full-time duty, under sections 316, 502, 503, 504, or 505 of title 32 [U. S. Code] or the prior corresponding provisions of law. 38 U.S.C. § 101(23) (West 2002); 38 C.F.R. § 3.6(d) (2021).

Thus, with respect to the Veteran's Reserves service, service connection may only be granted for disability resulting from disease or injury incurred or aggravated while performing ACDUTRA, or an injury incurred or aggravated while performing INACDUTRA. 38 U.S.C. §§ 101(24), 106, 1110, 38 C.F.R. §§ 3.6, 3.303, 3.304. Service connection is generally not legally merited when a disability incurred on INACDUTRA results from a disease process. See Brooks v. Brown, 5 Vet. App. 484, 487 (1993).

Certain evidentiary presum
6(d) (2021).

Certain evidentiary presumptions-such as the presumption of sound condition at entrance to service, the presumption of aggravation during service of preexisting diseases or injuries which undergo an increase in severity during service, and the presumption of service incurrence for certain diseases, which manifest themselves to a degree of disability of 10 percent or more within a specified time after separation from service, are provided by law to assist veterans in establishing service connection for a disability or disabilities. 38 U.S.C. §§ 101, 1112, (West 2002); 38 C.F.R. § 3.304(b), 3.306, 3.307, 3.309 (2021).

However, the advantages of these evidentiary presumptions do not extend to those who claim service connection based on a period of ACDUTRA or INACDUTRA. Paulson v. Brown, 7 Vet. App. 466, 470-71 (1995) (noting that the Board did not err in not applying presumptions of sound condition and aggravation to appellant's claim where he served only on ACDUTRA and had not established any service-connected disabilities from that period); McManaway v. West, 13 Vet. App. 60, 67 (citing Paulson, 7 Vet. App. at 469-7, for the proposition that, "if a claim relates to period of [ACDUTRA], a disability must have manifested itself during that period; otherwise, the period does not qualify as active military service and claimant does not achieve veteran status for purposes of that claim.").

Veterans who, during active service, served in the Republic of Vietnam during the period beginning on January 9, 1962, and ending on May 7, 1975, shall be presumed to have been exposed to an herbicide agent, unless there is affirmative evidence of non-exposure. 38 U.S.C. §§ 1116; 38 C.F.R. § 3.307.

"Service in the Republic of Vietnam" includes service in the waters offshore and service in other locations if the conditions of service involved duty or visitation in the Republic of Vietnam. 38 C.F.R. §§ 3.307(a) (6) (iii), 3.313(a).

A veteran who served in certain locations between January 9, 1962, and May 7, 1975, shall be presumed to have been exposed during such service to an herbicide agent, unless there is affirmative evidence to establish that the veteran was not exposed to any such agent during that service. 38 U.S.C. § 1116 (f); 38 C.F.R. §§ 3.307 (a)(6)(iii), 3.307(d). Honoring Our Promise to Address Comprehensive Toxics (PACT) Act, Pub. L. 117-168 (August 10, 2022). In such circumstances, service connection may be granted on a presumptive basis for the diseases listed in 38 C.F.R. § 3.309(e). 38 U.S.C. § 1116(a)(1); 38 C.F.R. § 3.307 (a)(6)(ii). When a claimed disability is not included as presumptive disorder, a veteran may nevertheless establish service connection based evidence of actual direct causation. See Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994); Brock v. Brown, 10 Vet. App. 155 (1997) (applying principle to Agent Orange exposure).

The diseases presumed to be associated with herbicide exposure include: chloracne or other acneform diseases consistent with chloracne, type 2 diabetes (also known as type II diabetes or adult-onset diabetes), Hodgkin's disease, ischemic heart disease (including, but not limited to, acute, subacute, and old myocardial infarction; atherosclerotic cardiovascular disease including coronary artery disease (including coronary spasm) and coronary bypass surgery; and stable, unstable and Prinzmetal's angina), all chronic B-cell leukemias (including, but not limited to, hairy-cell leukemia and chronic lymphocytic leukemia), multiple myeloma, non-Hodgkin's lymphoma, Parkinson's disease, acute and subacute peripheral neuropathy, porphyria cutanea tarda, prostate cancer, respiratory cancers (cancer of the lung, bronchus, larynx, or trachea), and soft-tissue sarcomas (other than osteosarcoma, chondrosarcoma, Kaposi's sarcoma, or mesothelioma). 38 C.F.R. § 3.309 (e). In addition, the National Defense Authorization Act for Fiscal Year 2021, P. L. 116-283, § 6501, 134 Stat. 3388 (Jan. 1, 2021) added bladder cancer to the list of conditions presumptively associated with exposure to herbicide agents, and the Honoring our PACT Act of 2022, Pub. L. 117-168 (August 10, 2022) recently added hypertension and monoclonal gammopathy of undetermined significance. 38 U.S.C. § 1116 (a)(2)(J).

VA's Secretary has determined that there is no positive association between exposure to herbicides and any other condition for which he has not specifically determined a presumption of service connection is warranted. See Diseases Not Associated with Exposure to Certain Herbicide Agents, 75 Fed. Reg. 81,332 (Dec. 27, 2010); see also Determinations Concerning Illnesses Discussed in National Academy of Sciences Report: Veterans and Agent Orange, 77 Fed. Reg. 47,924 (Aug. 10, 2012).

For the purposes of § 3.307, the term herbicide agent means a chemical in an herbicide used in support of the United States and allied military operations in the certain locations during the Vietnam era. 38 C.F.R. § 3.307 (a)(6)(i); Honoring our PACT Act of 2022 (August 10, 2022). Agent Orange is generally considered an herbicide agent and will be so considered in this decision.

The Board additionally notes that erectile dysfunction and obstructive sleep apnea are not listed as diseases that the VA has associated with herbicide exposure. Nevertheless, the regulations also provide that service connection may be granted for any disease diagnosed after discharge, when all evidence, including that pertinent to service, establishes that the disability was incurred in service. 38 C.F.R. §§ 3.303 (d), 3.309(e); see also Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994). In other words, a presumption of service connection provided by law is not the sole method for showing causation in establishing a claim for service connection for disability due to herbicide exposure. See Stefl v. Nicholson, 21 Vet. App. 120 (2007) (holding that the availability of presumptive service connection for some conditions based on exposure to Agent Orange does not preclude direct service connection for other conditions based on exposure to Agent Orange).

Diabetes Mellitus and Hypertension

Regulations provide that hypertension for VA purposes means that the diastolic blood pressure is predominantly 90 or more or systolic blood pressure is predominantly 160 or more. Hypertension must be confirmed by readings taken two or more times on three different days. 38 C.F.R. § 4.104, Diagnostic Code 7101, Note (1).

The Veteran contends that his diabetes mellitus and hypertension disabilities are related to in-service exposure to herbicides. Specifically, he contends that he was exposed to herbicides as a result of training at Fort Chaffee, Arkansas in 1967 and 1968. He reports that his "Retirement Point Sheet" and "DA Form 2-1" confirm his presence at the Fort Chaffee during this time
means that the diastolic blood pressure is predominantly 90 or more or systolic blood pressure is predominantly 160 or more. Hypertension must be confirmed by readings taken two or more times on three different days. 38 C.F.R. § 4.104, Diagnostic Code 7101, Note (1).

The Board observes that the Department of Defense (DoD) has provided VA with information concerning the operational use, testing, and disposal of Agent Orange and other herbicides outside of Vietnam. However, exposure to herbicides at these locations must be verified, as VA has not established a presumption of exposure. In this regard, a Department of Defense (DOD) 2019 list of locations where tactical herbicides and their chemical components were tested, used, or stored noted that herbicide application occurred at Fort Chaffee locations requiring vegetation control from May 16-18; July 22-23; and August 23-25, 1967.

In August 2024 and December 2024 memorandums, VA determined that the Veteran did not participate in a toxic exposure risk activity (TERA).

Per the June 2025 Board remand instructions, the AOJ underwent comprehensive research on the Veteran's claimed herbicide exposure. while serving at Fort Chaffee. A review of the evidence from National Archives and Records Administration (NARA) failed to verify herbicide exposure as claimed by the Veteran and concluded there was no evidence located to corroborate the Veteran's claims of exposure to Agent Orange while training at Fort Chaffee.

Specifically, September 2025 Records Research Center Responses noted that a professional researcher from NARA completed comprehensive research on the Veteran's claimed exposure event that while assigned to C Company, 2nd Battalion, 279th, 45th Infantry Division from January 1, 1967 to April 30, 1967, and from January 1, 1968 to April 30, 1968, he was exposed to herbicides while working in and around the base while on ACDUTRA. NARA was unable to locate the 1967 Operational Reports-Lessons Learned and Unit Histories for the 2nd Battalion, 279th, 45th Infantry Division. As a result, there was no evidence to support documentation of the claimed exposure event.

An October 2025 correspondence from VA indicated that records from the Defense Finance and Accounting Service (DFAS) could not be located and were unavailable for review.

Evidence submitted by the Veteran in January 2026 demonstrates that he was stationed at Fort Chaffee for periods including from May 26, 1967, to June 9, 1967. He was also shown to be at Fort Chaffee for periods including and August 1968, June 1969 and May 1970.

The U.S Department of Defense (DOD) again recognizes herbicides were at Fort Chaffee from May 16-18, 1967, July 23-25, 1967, and August 23-25, 1967.

However, the service records do not show the Veteran was assigned to Fort Chaffee, Arkansas, during the time periods listed above. (38 C.F.R. § 3.309).

The Veteran's service treatment records are silent for diabetes mellitus and hypertension disabilities conditions.

In March 2023 VA TERA opinions, a VA examiner opined that the Veteran's diabetes mellitus and hypertension disabilities were less likely than not caused by the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effet of all toxic exposure risk activities of the Veteran. The examiner noted that TERA exposure had not been conceded.

When considering the pertinent evidence of record in light of the above-noted legal authority, the Board finds that service connection for diabetes mellitus and hypertension disabilities is not warranted.

The Veteran has diagnoses of diabetes mellitus and hypertension disabilities and as a result, the first element of service connection is satisfied. However, a veteran seeking disability benefits must establish not only the existence of a disability, but also an etiological connection between his military service and the disability. Boyer v. West, 210 F.3d 1351, 1353 (Fed. Cir. 2000); D'Amico v. West, 209 F.3d 1322
Veteran. The examiner noted that TERA exposure had not been conceded.

The Veteran has diagnoses of diabetes mellitus and hypertension disabilities and as a result, the first element of service connection is satisfied. However, a veteran seeking disability benefits must establish not only the existence of a disability, but also an etiological connection between his military service and the disability. Boyer v. West, 210 F.3d 1351, 1353 (Fed. Cir. 2000); D'Amico v. West, 209 F.3d 1322, 1326 (Fed. Cir. 2000); Hibbard v. West, 13 Vet. App. 546, 548 (2000).

Regarding service connection on a direct basis, the Veteran's service treatment records are again negative for complaints, treatment or diagnoses related to diabetes mellitus and hypertension disabilities.

Further, there is no competent evidence or opinion even suggesting that there exists a medical nexus between current diabetes mellitus and hypertension disabilities and the Veteran's service and the Veteran has not presented or identified any such existing medical evidence or opinion.

Under 38 C.F.R. § 3.309 (a), the Veteran's diabetes mellitus and hypertension disabilities are considered a chronic condition for which service connection may be afforded on a presumptive basis if it were to have manifested to a compensable degree within one year following discharge from service. Given that the Veteran's diabetes mellitus and hypertension disabilities did not manifest until many years after service, he is not entitled to service connection on a presumptive basis under 38 C.F.R. § 3.309 (a).

To the extent that the Veteran is asserting that he experienced continuing symptoms of diabetes mellitus and hypertension thereafter, the Board acknowledges that a layperson is competent to testify in regard to the onset and continuity of symptomatology. Heuer v. Brown, 7 Vet. App. 379, 384 (1995); Falzone v. Brown, 8 Vet. App. 398, 403 (1995); Caldwell v. Derwinski, 1 Vet. App. 466 (1991). Furthermore, lay witnesses may, in some circumstances, opine on questions of diagnosis and etiology. See Davidson v. Shinseki, 581 F.3d 1313, 1316 (Fed. Cir. 2009) (finding that the Board's categorical statement that "a valid medical opinion" was required to establish nexus, and that a layperson was "not competent" to provide testimony as to nexus because she was a layperson, conflicts with Jandreau).

However, as the Veteran was not diagnosed with diabetes mellitus or hypertension until many years after service and there was a significant period between his service and his post-service complaints where the medical record was silent for complaints of diabetes mellitus and hypertension, the Board concludes that the weight of the evidence is against a finding of any continuity of symptomatology.

Regarding the possibility of exposure to certain herbicide agents, as listed under 38 C.F.R. § 3.307 (6)(i)(ii), a veteran who served in the Republic of Vietnam during the period from January 9, 1962, to May 7, 1975, may be afforded presumptive service connection for certain conditions, as noted under 38 C.F.R. §§ 3.309 (e), that become manifest to a degree of 10 percent or more at any time after service.

Additionally, the Sergeant First Class Heath Robinson Honoring our Promise to Address Comprehensive Toxics (PACT) Act, was enacted on August 10, 2022. See PACT Act, Pub. L. No. 117-168 § 3373, 136 Stat. 1759 (2022). Section 403 of the PACT Act expands the presumption of in-service herbicide agent exposure to additional territories and countries, including the U.S. or Royal Thai military base in Thailand from January 9, 1962, through June 30, 1976, without regard to where on the base the veteran was located or the military occupational specialty the veteran performed; Laos from December 1, 1965, through September 30, 1969; Mimot, Krek, or the Kampong Cham Province in Cambodia from April 16, 1969, through April 30, 1969; Guam or American Samoa or in the territorial waters of Guam or American Samoa from January 9, 1962, through July 30, 1980; or the Johnston Atoll or on a ship that called at Johnston Atoll from January 1, 197
or Royal Thai military base in Thailand from January 9, 1962, through June 30, 1976, without regard to where on the base the veteran was located or the military occupational specialty the veteran performed; Laos from December 1, 1965, through September 30, 1969; Mimot, Krek, or the Kampong Cham Province in Cambodia from April 16, 1969, through April 30, 1969; Guam or American Samoa or in the territorial waters of Guam or American Samoa from January 9, 1962, through July 30, 1980; or the Johnston Atoll or on a ship that called at Johnston Atoll from January 1, 1972, through September 30, 1977. Id. at § 403 (codified as amended at 38 U.S.C. § 1116). The PACT Act also adds hypertension as a presumptive disease associated with herbicides.

Pertinent here, the Veteran did not serve at any of the presumptive locations for herbicide. Instead, he argues that he was exposed to herbicides and other toxins at Fort Chaffee, Arkansas.

The U.S Department of Defense (DOD) again recognizes herbicides were at Fort Chaffee from May 16-18, 1967, July 23-25, 1967, and August 23-25, 1967.

However, the service records do not show the Veteran was assigned to Fort Chaffee, Arkansas, during the time periods listed above. (38 C.F.R. § 3.309).

Therefore, the Veteran does not meet the criteria for presumed exposure to herbicide agents and service connection based on presumed herbicide agent exposure is not warranted.

After a review of the evidence, the Board finds that the Veteran's service file and the aforementioned memorandums are the most probative evidence of record as to whether the Veteran was exposed to herbicide agents during his service.

There is no objective evidence confirming the Veteran's contention that he was exposed to Agent Orange. The Veteran has not indicated that he possesses any specialized knowledge in the scientific field such that he could determine without testing that he handled barrels containing herbicides. In Bardwell v. Shinseki, 24 Vet. App. 36 (2010), the Court held that a layperson's assertions indicating exposure to gases or chemicals during service are not sufficient evidence alone to establish that such an event actually occurred during service. Rather, those statements must be weighed against other evidence of record, including lack of documentary evidence of the incident.

Having considered the Veteran's contentions and statements, and after a review of all the evidence of record, the Board finds that the weight of the evidence demonstrates that the Veteran did not have "service in the Republic of Vietnam," was not presumptively exposed to herbicides during active service, and was not actually exposed to herbicides during service to warrant the presumption of service connection. See 38 C.F.R. § 3.307(a) (6) (iii).

As a result, while the Veteran served in the Vietnam era, the Board finds that he was not deployed to Vietnam, did not set foot in Vietnam and was not otherwise exposed to herbicides during his service. The Board further acknowledges the Veteran's service at Fort Chaffee but again, his service there does not show service from May 16-18, 1967, July 23-25, 1967, and August 23-25, 1967, at Fort Chafee.

Accordingly, while type II diabetes mellitus and hypertension are diseases that would warrant a regulatory presumption of service connection for as a result of in-service herbicide exposure, this is not applicable to the Veteran's claim. Accordingly, service connection is not warranted on a presumptive basis.

In sum, for the reasons and bases expressed above the Board finds that the most persuasive evidence is against the Veteran's claims of entitlement to service connection for type II diabetes mellitus and hypertension disabilities. The benefit-of-the-doubt rule does not apply, and the claims must be denied. 38 U.S.C. § 5107(b).

Obstructive Sleep Apnea

The Veteran contends that his obstructive sleep apnea is directly related to his in-service herbicide agent exposure and is secondary to his service-connected tinnitus

As reflected above, VA has again not conceded the Veteran's claim herbicide agent exposure. However, he is service connected for tinnitus.

The Veteran underwent a VA examination in July 2023. The examiner opined that the Veteran's sleep apnea was less likely than not proximately due to or the result of the Veteran's tinnitus. The examiner noted that there were no known pathophysiological relationships between obstructive sleep apnea and tinnitus.

The Veteran again
be denied. 38 U.S.C. § 5107(b).

Obstructive Sleep Apnea

The Veteran contends that his obstructive sleep apnea is directly related to his in-service herbicide agent exposure and is secondary to his service-connected tinnitus

As reflected above, VA has again not conceded the Veteran's claim herbicide agent exposure. However, he is service connected for tinnitus.

The Veteran again underwent a VA examination in July 2024. The examiner opined that the Veteran's sleep apnea was less likely than not proximately due to or the result of the Veteran's tinnitus. The examiner noted that the conditions of obstructive sleep apnea and tinnitus were not medically related as obstructive sleep apnea was an entirely separate entity unrelated to tinnitus.

In a January 2025 addendum opinion, the July 2024 VA examiner opined that it was less likely than not that the Veteran's obstructive sleep apnea was aggravated beyond its natural progression as a result of his service-connected tinnitus.

When considering the pertinent evidence of record in light of the above-noted legal authority, the Board finds that service connection for an obstructive sleep apnea disability to include as secondary to a service-connected disability is not warranted.

As there is a current diagnosis of obstructive sleep apnea, the first element of service connection is satisfied. However, a veteran seeking disability benefits must establish not only the existence of a disability, but also an etiological connection between his military service and the disability. Boyer v. West, 210 F.3d 1351, 1353 (Fed. Cir. 2000); D'Amico v. West, 209 F.3d 1322, 1326 (Fed. Cir. 2000); Hibbard v. West, 13 Vet. App. 546, 548 (2000).

The Board notes that the Veteran's service treatment records are negative for complaints or treatments for an obstructive sleep apnea disability.

Further, there is no competent evidence or opinion even suggesting that there exists a medical nexus between a current obstructive sleep apnea disability and the Veteran's service and the Veteran has not presented or identified any such existing medical evidence or opinion.

The Board finds that the competent evidence of record, while showing the currently diagnosed obstructive sleep apnea disability, does not demonstrate that the Veteran's obstructive sleep apnea disability is related to the Veteran's service.

Consequently, entitlement to service connection for obstructive sleep apnea is not warranted on a direct basis.

Regarding service connection on a secondary basis, the Board again notes that the Veteran asserts that his obstructive sleep apnea is either caused or aggravated by his service-connected tinnitus.

However, the Board finds that the weight of the evidence is against a finding that a current obstructive sleep apnea disability is related to service or caused or aggravated by a service-connected disability. Again, the only medical opinions addressing the etiology of the disability on a secondary basis weigh against the claim as the July 2023 and July 2024 VA examiners indicated that the Veteran's obstructive sleep apnea was less likely than not caused or by his service-connected tinnitus. Additionally, in a January 2025 addendum opinion, the VA examiner found that it was less likely than not that the Veteran's obstructive sleep apnea was aggravated beyond its natural progression by the service-connected tinnitus.

None of the competent medical evidence currently of record refutes these conclusions, and the Veteran has not presented or identified any such existing medical evidence or opinion.

The Board also affords the VA examiners' opinions, which are supported by a detailed rationale and medical knowledge, great probative value.

Consequently, entitlement to service connection for an obstructive sleep apnea disability is also not warranted on a secondary basis.

In sum, for the reasons and bases expressed above the Board finds that the most persuasive evidence is against the Veteran's claim of entitlement to service connection for an obstructive sleep apnea disability. The benefit-of-the-doubt rule does not apply, and the claim must be denied. 38 U.S.C. § 5107(b).

Erectile Dysfunction

The Veteran's service treatment records are negative for treatments or complaints of erectile dysfunction.

The Veteran underwent a VA examination in March 2023. The examiner opined that the Veteran's erectile dysfunction was less likely than not caused by the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable military deployments of the Veteran and
on a secondary basis.

Erectile Dysfunction

The Veteran's service treatment records are negative for treatments or complaints of erectile dysfunction.

When considering the pertinent evidence of record in light of the above-noted legal authority, the Board finds that service connection for an erectile dysfunction disability to include as secondary to a service-connected disability is not warranted.

As there is a current diagnosis of erectile dysfunction, the first element of service connection is satisfied. However, a veteran seeking disability benefits must establish not only the existence of a disability, but also an etiological connection between his military service and the disability. Boyer v. West, 210 F.3d 1351, 1353 (Fed. Cir. 2000); D'Amico v. West, 209 F.3d 1322, 1326 (Fed. Cir. 2000); Hibbard v. West, 13 Vet. App. 546, 548 (2000).

Notably, the Veteran's service treatment records are negative for complaints or treatments for an erectile dysfunction disability to include at his separation examination.

Additionally, the only medical opinions addressing the etiology of the erectile dysfunction disability weigh against the claim as the March 2023 VA examiner opined that the Veteran's erectile dysfunction was less likely than not caused by the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effet of all toxic exposure risk activities of the Veteran.

Further, there is no competent evidence or opinion even suggesting that there exists a medical nexus between a current erectile dysfunction disability and the Veteran's service and the Veteran has not presented or identified any such existing medical evidence or opinion.

The Board finds that the competent evidence of record, while showing the currently diagnosed erectile dysfunction disability, does not demonstrate that the Veteran's erectile dysfunction disability is related to the Veteran's service.

Consequently, entitlement to service connection for an erectile dysfunction disability is not warranted on a direct basis.

Regarding service connection on a secondary basis, as noted above, service connection may be granted for a disability that is proximately due to or the result of an established service-connected disability. 38 C.F.R. § 3.310 (2021).

The Veteran has claimed that his erectile dysfunction disability is the result of his type II diabetes mellitus which was incurred during his service. However, the Veteran is not currently service connected for a diabetes mellitus disability as addressed above.

Hence, as a matter of law, the claim for service connection for an erectile dysfunction disability as secondary to a diabetes mellitus disability is without legal merit, and must be denied as a matter of law. See 38 C.F.R. § 3.310(a); Sabonis v. Brown, 6 Vet. App. 426, 430 (1994).

Consequently, entitlement to service connection for erectile dysfunction is not warranted on a direct or secondary basis.

In sum, for the reasons and bases expressed above the Board finds that the most persuasive evidence is against the Veteran's claim of entitlement to service connection for an erectile dysfunction disability. The benefit-of-the-doubt rule does not apply, and the claim must be denied. 38 U.S.C. § 5107(b).

All Disabilities

The Board notes that the Veteran was not provided with a VA examination and opinions to assess the current nature and etiology of his claimed diabetes mellitus, hypertension, obstructive sleep apnea and erectile dysfunction disabilities on a direct basis. However, VA need not conduct an examination with respect to the claims on appeal, as information and evidence of record contains sufficient competent medical evidence to decide the claims. See 38 C.F.R. § 3.159(c) (4). Under McLendon v. Nicholson, 20 Vet. App. 79 (2006), in disability compensation (service connection) claims, the VA must provide a VA medical examination when there is (1) competent evidence of a current disability or persistent or recurrent symptoms of a disability, and (2) evidence establishing that an event, injury, or disease occurred in service or establishing certain diseases manifesting during an applicable presumptive
, obstructive sleep apnea and erectile dysfunction disabilities on a direct basis. However, VA need not conduct an examination with respect to the claims on appeal, as information and evidence of record contains sufficient competent medical evidence to decide the claims. See 38 C.F.R. § 3.159(c) (4). Under McLendon v. Nicholson, 20 Vet. App. 79 (2006), in disability compensation (service connection) claims, the VA must provide a VA medical examination when there is (1) competent evidence of a current disability or persistent or recurrent symptoms of a disability, and (2) evidence establishing that an event, injury, or disease occurred in service or establishing certain diseases manifesting during an applicable presumptive period for which the claimant qualifies, and (3) an indication that the disability or persistent or recurrent symptoms of a disability may be associated with the Veteran's service or with another service-connected disability, but (4) insufficient competent medical evidence on file for the VA to make a decision on the claim. Simply stated, the standards of McLendon are not met in this case as there is no credible evidence that the diabetes mellitus, hypertension, obstructive sleep apnea and erectile dysfunction disabilities manifested in service. There is also no competent evidence suggesting that these disabilities are otherwise associated to service. Thus, remand for additional VA examinations is not necessary.

The Board notes the Veteran and his representative's contentions regarding the etiology of the claimed hypertension, type II diabetes mellitus, sleep apnea and erectile dysfunction disabilities. To the extent that the Veteran and his representative themselves contend that a medical relationship exists between the Veteran's claimed hypertension, type II diabetes mellitus, sleep apnea and erectile dysfunction disabilities and his service, the Board acknowledges that the Veteran is competent to testify as to his observations. Jandreau v. Nicholson, 492 F.3d 1372, 1376-77 (Fed. Cir. 2007). Furthermore, lay witnesses may, in some circumstances, opine on questions of diagnosis and etiology. See Davidson v. Shinseki, 581 F.3d 1313, 1316 (Fed. Cir. 2009) (finding that the Board's categorical statement that "a valid medical opinion" was required to establish nexus, and that a layperson was "not competent" to provide testimony as to nexus because she was a layperson, conflicts with Jandreau). In the instant case, however, the Board finds that hypertension, type II diabetes mellitus, sleep apnea and erectile dysfunction disabilities are not disabilities subject to lay diagnosis as these diagnoses require medical training. More significantly, the Veteran and his representative do not have the medical expertise to provide an opinion regarding the claimed hypertension, type II diabetes mellitus, sleep apnea and erectile dysfunction disabilities etiologies. Specifically, where the determinative issue is one of medical causation, only those with specialized medical knowledge, training, or experience are competent to provide evidence on the issue. See Jones v. West, 12 Vet. App. 460, 465 (1999). Additionally, the VA examiners provided detailed rationales in support of their opinions and cited to the relevant evidence. For this reason, the VA examiners' opinions are the most probative evidence of record. See Prejean v. West, 13 Vet. App. 444, 448-9 (2000) (noting that a factor for assessing the probative value of a medical opinion includes the thoroughness and detail of the opinion).

Thus, the Veteran and his representative's assertions that there is a relationship between the claimed hypertension, type II diabetes mellitus, sleep apnea and erectile dysfunction disabilities and the Veteran's service are not sufficient in this instance and are outweighed by other probative evidence of record. Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007).

REASONS FOR REMAND

The Board finds that more development is necessary prior to final adjudication of the claims remaining on appeal.

Regarding the Veteran's claimed coronary artery disease disability, the Veteran underwent VA examination in March 2023. The VA examiner opined that the Veteran's current coronary artery disease was less likely than not caused by the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effet of all toxic exposure risk activities of the Veteran.

However, the March 2023 VA opinions were insufficient as the examiner did not address the Veteran's claimed disability on a direct basis. Notably, the Veteran's service treatment records demonstrate that the Veteran presented with complaints of tightening in his chest in June 1967 where he also noted that he thought he had experienced a heart attack.

Thus, the Board finds that the evidence currently
disability, the Veteran underwent VA examination in March 2023. The VA examiner opined that the Veteran's current coronary artery disease was less likely than not caused by the indicated toxic exposure risk activity(ies), after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effet of all toxic exposure risk activities of the Veteran.

Thus, the Board finds that the evidence currently of record is insufficient to resolve the claim for entitlement to service connection for coronary artery disease and that further opinion in connection with this claim is necessary for a fully informed evaluation of the claim on appeal. Green v. Derwinski, 1 Vet. App. 121, 124 (1991); 38 C.F.R. § 3.159(c) (4).

The Veteran has also argued that he has been unable to work a result of his service-connected disabilities.

However, because a decision on the remanded issue of entitlement to service connection for coronary artery disease could significantly impact a decision on the issue of entitlement to TDIU, the issues are inextricably intertwined. See Harris v. Derwinski, 1 Vet. App. 180, 183 (1991) (providing that two issues are "inextricably intertwined" when they are so closely tied together that a final Board decision cannot be rendered unless both issues have been considered). Thus, remand of the claim for TDIU is warranted.

On remand, the AOJ will readjudicate the claims for an increased rating and TDIU. In so doing, the AOJ will consider all relevant evidence of record,

The Board noted that AMA provides that remands are warranted based on VA's duty to assist prior to the AOJ decision. Pub. L. No. 115-55, § 2(d)(2). The AMA structure allows remand only where VA has committed error in the duty-to-assist (DTA) prior to the decision on appeal. After a thorough review of the record, the Board finds the arguments of the Veteran's representative to be compelling. In requesting additional development on remand in this case, the Board notes that the basis for this remand arises from deficiencies in the record existing prior to the appealed October 2025 AMA decision. Notably, prior to the rating decision, there was evidence of a possible in-service incurrence of coronary artery disease as the Veteran's service treatment records demonstrate complaints of chest tightness. As noted above, despite the in-service complaint, the Veteran was not provided with a VA examination to address his claim service connection for coronary artery disease on a direct basis.

Thus, the Board finds that a remand is necessary in order to provide the Veteran with etiological opinions with respect to this claimed condition as there exists a pre-decisional duty to assist error and the claim must be remanded.

The matters are REMANDED for the following action:

1. The Veteran should be scheduled for a VA examination to determine the etiology of the claimed coronary artery disease disability.

2. Based on a review of the record and an examination of the Veteran, the examiner should provide an opinion as to whether it is at least as likely as not (likelihood is at least approximately balanced or nearly equal, if not higher) that the Veteran's has a current coronary heart disease disability that is related to any incident of the Veteran's active-duty service and active duty for training (ACDUTRA) service.

The examiner should specifically consider the Veteran's documented in-service complaints of tightening in chest in June 1967.

All opinions expressed by the examiner must be accompanied by a complete rationale.

Adequate reasons and bases for any opinion rendered must be provided. All studies deemed appropriate in the medical opinion of the examiner should be performed, and all the findings should be set forth in detail. The claims file should be made available to the examiner, who should review the entire claims folder in conjunction with this examination.

2. Readjudicate the claim for a TDIU.

R. Bisignani

Veterans Law Judge

Board of Veterans' Appeals

Attorney for the Board James A. DeFrank

The Board's decision in this case is binding only with respect to the instant matter decided. This decision is not precedential and does not establish VA policies or interpretations of general applicability. 38 C.F.R. § 20.1303.

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