DIABETES MELLITUS

TANYA SMITH · 2026 · Case ID: 26003809

MIXED

Summary

The veteran, who served from May 1958 to August 1961, appeals the denial of service connection for diabetes mellitus, type 2, and decreased vision in the left eye. The veteran also claimed exposure to asbestos, ionizing radiation, and PCBs during service. The Board granted service connection for diabetes mellitus, type 2, on a secondary basis to his service-connected chronic kidney disease, finding that while the veteran's diabetes was not directly caused by service or toxic exposures, the chronic kidney disease could modify glucose handling in someone with diabetes. The Board also granted service connection for bilateral diabetic retinopathy with macular edema, finding it was caused by the newly service-connected diabetes mellitus, type 2. The Board resolved all reasonable doubt in the veteran's favor for these granted claims. However, the Board remanded claims for other decreased vision issues, including bilateral glaucoma, PCIOL of the left eye, and nuclear sclerosis of the right eye. The VA examiner's opinion regarding the Veteran's diabetes was unfavorable, stating it was less likely than not caused by toxic exposures, and the Board found this opinion persuasive. The Board also noted the lack of a contrary medical opinion from the veteran. The veteran's claims for other eye conditions were remanded for further development, including opinions on service connection and aggravation by diabetes.

Rationale

Diabetes mellitus, type 2, is not a radiogenic disease.; No evidence of onset during service or within one year post-service.; VA examiner opined diabetes was less likely than not caused by TERAs.; Board found diabetes not causally or etiologically due to service.; Chronic kidney disease can modify glucose handling in diabetics.; Benefit of the doubt resolved in Veteran's favor for this grant.

Special Benefit

NO SPECIAL BENEFIT

Docket No.

21-00 845A

Full Decision Text

Citation Nr: 26003809
Decision Date: 03/25/26 Archive Date: 03/25/26

DOCKET NO. 21-00 845A
DATE: March 25, 2026

ORDER

Entitlement to service connection for diabetes mellitus, type 2, as secondary to service-connected chronic kidney disease, is granted.

Entitlement to service connection for bilateral diabetic retinopathy with macular edema (claimed as decreased vision in the left eye), as secondary to diabetes mellitus, type 2, is granted.

REMANDED

Entitlement to service connection for decreased vision, other than bilateral diabetic retinopathy with macular edema, to include bilateral glaucoma, posterior chamber intraocular lens (PCIOL) of the left eye, and nuclear sclerosis of the right eye, (claimed as decreased vision in the left eye), is remanded.

FINDINGS OF FACT

1. The Veteran's diabetes mellitus, type 2, is aggravated by his service-connected chronic kidney disease.

2. The Veteran's diabetic retinopathy with macular edema is caused by his diabetes mellitus, type 2.

CONCLUSIONS OF LAW

1. The criteria for service connection for diabetes mellitus, type 2, as secondary to chronic kidney disease, are met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310.

2. The criteria for service connection for bilateral diabetic retinopathy with macular edema, as secondary to diabetes mellitus, type 2, are met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310.

REASONS AND BASES FOR FINDINGS AND CONCLUSIONS

The Veteran had active service from May 1958 to August 1961.

This matter is in the legacy system and comes before the Board of Veterans' Appeals (Board) on appeal from a September 2018 rating decision.

The Veteran was afforded a hearing before the undersigned Veterans Law Judge in October 2022. A transcript of the hearing is associated with the electronic claims file.

In a March 2023 decision, the Board granted entitlement to service connection for bilateral hearing loss and tinnitus, and remanded the issues of entitlement to service connection for prostate cancer, diabetes mellitus, type 2, and decreased vision of the left eye. Service connection for prostate cancer was granted in a November 2025 rating decision, and as such, is no longer before the Board.

Service Connection

1. Entitlement to service connection for diabetes mellitus, type 2.

The Veteran seeks entitlement to service connection for diabetes mellitus, type 2. He asserts he was exposed to asbestos, ionizing radiation, and polychlorinated biphenyls (PCBS) during service.

In general, service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by service. 38 U.S.C. §§ 1110, 1131; 38 C.F.R. §§ 3.303, 3.304.

Service connection generally requires credible and competent evidence showing: (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. See Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004).

Certain chronic diseases, including diabetes mellitus, will be presumed related to service, absent an intercurrent cause, if they were shown as chronic in service; or, if they manifested to a compensable degree within a presumptive period following separation from service; or, if they were noted in service (or within an applicable presumptive period) with continuity of symptomatology since service that is attributable to the chronic disease. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.303, 3.307, 3.309. Walker v. Shinseki, 708 F.3d 1331, 1338 (Fed. Cir. 2013).

Service connection for claims based on exposure to ionizing radiation in service can be established in any of three different ways. See Davis v. Brown, 10 Vet. App. 209, 211 (1997); Rucker v. Brown, 10 Vet. App. 67, 71 (1997). First, there are diseases that are
the chronic disease. 38 U.S.C. §§ 1101, 1112, 1113, 1137; 38 C.F.R. §§ 3.303, 3.307, 3.309. Walker v. Shinseki, 708 F.3d 1331, 1338 (Fed. Cir. 2013).

Service connection for claims based on exposure to ionizing radiation in service can be established in any of three different ways. See Davis v. Brown, 10 Vet. App. 209, 211 (1997); Rucker v. Brown, 10 Vet. App. 67, 71 (1997). First, there are diseases that are presumptively service connected in radiation-exposed veterans under 38 U.S.C. § 1112(c) and 38 C.F.R. § 3.309(d). Second, service connection can be established under 38 C.F.R. § 3.303(d) with the assistance of the procedural advantages prescribed in 38 C.F.R. § 3.311 if the condition at issue is a radiogenic disease. Third, direct service connection can be established under 38 C.F.R. § 3.303(d) by showing that the disease was incurred in or aggravated by service without regard to the statutory presumptions. See Combee v. Brown, 34 F.3d 1039, 1043-44 (Fed. Cir. 1994).

A radiation-exposed veteran is defined by 38 C.F.R. § 3.309(d)(3) as a veteran who, while serving on active duty or on active duty for training or inactive duty training, participated in a radiation-risk activity. 38 C.F.R. § 3.309(d)(3)(i), (ii).

Importantly, diseases presumptively service connected for radiation-exposed veterans under the provisions of 38 U.S.C. § 1112(c) and 38 C.F.R. § 3.309(d)(2) do not include diabetes mellitus. 38 U.S.C. § 1112(c)(2); 38 C.F.R. § 3.309(d).

If a claimant does not qualify as a radiation-exposed veteran under 38 C.F.R. § 3.309(d)(3) and/or is not diagnosed with one of the presumptive conditions listed in 38 C.F.R. § 3.309(d)(2), the Veteran may still benefit from the special development procedures provided in 38 C.F.R. § 3.311 if the Veteran suffers from a radiogenic disease and claims exposure to ionizing radiation in service.

Regulation 38 C.F.R. § 3.311 establishes a procedural framework for developing and considering claims for service connection for radiogenic diseases. It does not provide a presumption of service connection.

Under 38 C.F.R. § 3.311, radiogenic disease means a disease that may be induced by ionizing radiation. Importantly, it does not include diabetes mellitus. 38 C.F.R. § 3.311(b)(2).

Under the special development procedures in § 3.311(a), dose data will be requested from the Department of Defense in claims based upon participation in atmospheric nuclear testing, and claims based upon participation in the American occupation of Hiroshima or Nagasaki, Japan, prior to July 1, 1946. 38 C.F.R. § 3.311(a)(2). In all other claims, 38 C.F.R. § 3.311(a) requires that a request be made for any available records concerning the Veteran's exposure to radiation. All such records will be forwarded to the Under Secretary for Health, who will be responsible for preparation of a dose estimate, to the extent feasible, based on available methodologies. 38 C.F.R. § 3.311(a)(2)(iii).

Under Combee, VA must not only determine whether a veteran had a disability recognized by VA as being etiologically related to exposure to ionizing radiation, but it must also determine whether the disability was otherwise the result of active service. In other words, the fact that the requirements of a presumptive regulation are not met does not in and of itself preclude a claimant from establishing service connection by way of proof of actual direct causation.

In making all determinations, the Board must fully consider the lay assertions of record. A layperson is competent to report on the onset and continuity of current symptomatology. See Layno v. Brown, 6 Vet. App. 465, 470 (1994).

Establishing service connection on a secondary basis requires evidence sufficient to show (1) that a current disability exists and (2) that the current disability was either (a
izing radiation, but it must also determine whether the disability was otherwise the result of active service. In other words, the fact that the requirements of a presumptive regulation are not met does not in and of itself preclude a claimant from establishing service connection by way of proof of actual direct causation.

The Board is granting this claim on a secondary basis. Direct service connection is not warranted.

The Veteran has a current diagnosis of diabetes mellitus, type 2. See, e.g., November 2025 VA examination.

As noted, diabetes mellitus is not a disease presumptively associated with exposure to ionizing radiation and it is not considered a radiogenic disease. Furthermore, there is no evidence in the service treatment records of an onset of diabetes mellitus, type 2, during service or within one year following discharge from service. The Veteran has not asserted that he began experiencing symptoms during service.

A VA medical opinion was obtained in November 2025, at which time the VA examiner opined that the Veteran's diabetes was less likely than not caused by the Veteran's toxic exposure risk activities, after considering the total potential exposure throughout military deployments and the synergistic, combined effect of all toxic exposure risk activities of the Veteran. The examiner explained that diabetes mellitus, type 2, is due to insulin resistance and the identified toxic exposure risk activities (TERAs) are not implicated in this etiology. The examiner explained that there is no medical or scientific evidence that provides any indication of a relationship between the development of diabetes mellitus, and the TERAs.

The Board finds that the weight of the evidence demonstrates that the Veteran's diabetes mellitus, type 2, is not causally or etiologically due to service. Here, the VA medical examiner considered the evidence of record, yet still opined that the Veteran's diabetes mellitus, type 2, was not due to his time in service, to include his TERAs. The VA medical opinion is based on an accurate history, medical expertise, and training, is supported by a sound rationale, and is therefore of significant probative value, when considered in totality.

Importantly, the Veteran has not provided a contrary medical opinion. See Fagan v. Shinseki, 573 F.3d 1282, 1287 (Fed. Cir. 2009) (holding that it is the claimant's general evidentiary burden to establish all elements of the claim). The Veteran is competent to report symptoms and provide diagnoses that are capable of lay observation but is not competent to establish that which would require specialized knowledge or training, such as medical expertise. See Layno v. Brown, 6 Vet. App. 465, 469-70 (1994). The record does not show, nor does the Veteran contend that he has specialized education, training, or experience that would qualify him to render a diagnosis or render a medical opinion on this matter. The development of diabetes mellitus, type 2, is a complicated medical determination requiring specialized knowledge and is not capable of lay observation. See Jandreau v. Nicholson, 492 F.3d 1372, 1377 n.4 (Fed. Cir. 2007); Kahana v. Shinseki, 24 Vet. App. 428, 435 (2011).

For these reasons, the Board finds that the weight of the lay and medical evidence shows that the Veteran's diabetes mellitus, type 2, is not causally or etiologically due to service. However, as noted, the Board finds that the Veteran's diabetes mellitus, type 2, is aggravated by his service-connected chronic kidney disease.

A VA medical opinion was obtained in December 2025, at which the examiner explained that research indicates advanced chronic kidney disease may alter insulin metabolism in individuals who already have diabetes. The examiner stated that these metabolic changes, reduced renal insulin clearance, altered gluconeogenesis and changes in insulin receptor sensitivity do not cause diabetes to develop in someone who did not previously have it, but they do modify glucose handling once diabetes is already present. An addendum opinion was then obtained in December 2025. The December 2025 VA examiner, however, utilized the incorrect standard of "permanent worsening" in providing the addendum medical
noted, the Board finds that the Veteran's diabetes mellitus, type 2, is aggravated by his service-connected chronic kidney disease.

A VA medical opinion was obtained in December 2025, at which the examiner explained that research indicates advanced chronic kidney disease may alter insulin metabolism in individuals who already have diabetes. The examiner stated that these metabolic changes, reduced renal insulin clearance, altered gluconeogenesis and changes in insulin receptor sensitivity do not cause diabetes to develop in someone who did not previously have it, but they do modify glucose handling once diabetes is already present. An addendum opinion was then obtained in December 2025. The December 2025 VA examiner, however, utilized the incorrect standard of "permanent worsening" in providing the addendum medical opinion. The Board notes that service connection on a secondary basis is warranted for any incremental increase in disability, regardless of its permanence. See Ward v. Wilkie, 31 Vet. App. 233 (2019).

Therefore, the Board finds that service connection for diabetes mellitus, type 2, is warranted on a secondary basis to his service-connected chronic kidney disease, as the December 2025 VA medical opinion indicates chronic kidney disease can modify glucose handling in someone who already has diabetes. In so finding, all reasonable doubt has been resolved in favor of the Veteran.

2. Entitlement to service connection for bilateral diabetic retinopathy with macular edema.

The Veteran also seeks entitlement to service connection for decreased vision. The Board notes that the Veteran limited his original claim to the left eye; however, the issue has been expanded to include both eyes in order to award the Veteran maximized benefits.

As a result of this Board decision, service connection has been awarded for diabetes mellitus, type 2. In a May 2024 VA examination, the Veteran was diagnosed with proliferative diabetic retinopathy with macular edema in both eyes. In an October 2024 opinion, the VA examiner explained that diabetic retinopathy is most likely caused by diabetes, secondary to long term diabetes and uncontrolled blood sugar.

As such, service connection for bilateral diabetic retinopathy with macular edema is granted, as caused by his diabetes mellitus, type 2. In so finding, all reasonable doubt has been resolved in the Veteran's favor.

REASONS FOR REMAND

3. Entitlement to service connection for decreased vision, other than bilateral diabetic retinopathy with macular edema, to include bilateral glaucoma, PCIOL of the left eye, and nuclear sclerosis of the right eye.

As a result of this Board decision, the Veteran has been granted service connection for bilateral diabetic retinopathy with macular edema. However, the Veteran has several additional diagnoses pertaining to the eyes. In particular, the Veteran is diagnosed with bilateral glaucoma, PCIOL of the left eye, and nuclear sclerosis of the right eye.

In an October 2025 opinion, a VA examiner opined that the Veteran's cataracts and PCIOL are less likely a result of the Veteran's diabetes mellitus, type 2, and stated that the Veteran's glaucoma is secondary to optic nerve changes and IOP changes.

The October 2025 VA opinion does not address whether the Veteran's diabetes mellitus, type 2, aggravates his bilateral glaucoma, PCIOL of the left eye, and nuclear sclerosis of the right eye. The Board finds an addendum opinion is necessary that addresses aggravation.

Additionally, an addendum opinion was obtained in December 2024 regarding whether the Veteran's eye disorders were causally or etiologically due to service. The VA examiner opined that the Veteran's diabetic retinopathy with macular edema was less likely than not caused by radiofrequency radiation. However, no medical opinion was provided for the Veteran's remaining diagnoses of bilateral glaucoma, PCIOL of the left eye and nuclear sclerosis of the right eye. On remand, an addendum opinion should be obtained.

The matters are REMANDED for the following action:

1. Obtain and associate with the claims file all updated treatment records.

2. Obtain an addendum opinion for the Veteran's decreased vision, other than bilateral diabetic retinopathy with macular edema, to include bilateral glaucoma, PCIOL of the left eye, and nuclear sclerosis of the right eye.

The claims file must be made available to and reviewed by the examiner.

The examiner must address the following:

Is it approximately at least as likely as not that:

a) the Veteran's bilateral glaucoma is causally or etiologically due to service;

b) the Veteran's PCIOL of the left eye (due to cataract) is causally or etiologically due to service; and,

c) the Veteran's nuclear sclerosis of the right eye is causally or etiologically due to service.

In answering these questions,
's decreased vision, other than bilateral diabetic retinopathy with macular edema, to include bilateral glaucoma, PCIOL of the left eye, and nuclear sclerosis of the right eye.

The claims file must be made available to and reviewed by the examiner.

The examiner must address the following:

Is it approximately at least as likely as not that:

a) the Veteran's bilateral glaucoma is causally or etiologically due to service;

b) the Veteran's PCIOL of the left eye (due to cataract) is causally or etiologically due to service; and,

c) the Veteran's nuclear sclerosis of the right eye is causally or etiologically due to service.

In answering these questions, the examiner must consider the total potential exposure through all applicable deployments and the synergistic, combined effect of all his toxic exposure risk activities.

The examiner must additionally address the following:

Is it approximately at least as likely as not that:

d) the Veteran's bilateral glaucoma is aggravated by his diabetes mellitus, type 2;

e) the Veteran's PCIOL of the left eye (due to cataract) is aggravated by his diabetes mellitus, type 2; and,

f) the Veteran's nuclear sclerosis of the right eye is aggravated by his diabetes mellitus, type 2.

Any opinion rendered should be accompanied by a complete rationale that includes discussion of the facts of the case and pertinent medical principles.

TANYA SMITH

Veterans Law Judge

Board of Veterans' Appeals

Attorney for the Board L. Andersen, Counsel

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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