DIABETES MELLITUS

Summary

The Veteran, who served in the Army National Guard from August 1968 to December 1968, appeals the denial of service connection for type 2 diabetes mellitus and bilateral peripheral neuropathy of the lower extremities. The Veteran's service treatment records were silent regarding these conditions, with the separation examination showing normal results. The Veteran was diagnosed with type 2 diabetes mellitus and bilateral peripheral neuropathy in approximately 2007 and 2005, respectively, well after service. VA examinations in October 2025 and January 2026 found no service connection, noting that the Veteran's risk factors for diabetes and neuropathy, such as age, hypertension, obesity, and diabetes itself, outweighed any potential TERA exposure. While TERA exposure was conceded, medical literature did not support a link to the Veteran's conditions. Opinions also found no nexus between the peripheral neuropathy and the Veteran's service-connected PTSD, TBI, tinnitus, or Meniere's syndrome, nor did they find evidence of aggravation. The Board found the VA opinions persuasive and supported by rationale, concluding that the evidence was against the claim and the benefit-of-the-doubt rule was not applicable. Service connection for all claimed conditions was denied.

Rationale

No in-service complaints, findings, treatment, or diagnosis; Diagnosed approximately 30 years post-service; VA opinions found no nexus to service or TERA; Attributed to non-TERA risk factors (age, hypertension, obesity); No evidence of aggravation or secondary connection to service-connected conditions

Full Decision Text

Citation Nr: 26004568
Decision Date: 04/15/26	Archive Date: 04/15/26

DOCKET NO. 17-39 623
DATE: April 15, 2026

ORDER

Entitlement to service connection for type 2 diabetes mellitus is denied.

Entitlement to service connection for peripheral neuropathy of the right lower extremity is denied.

Entitlement to service connection for peripheral neuropathy of the left lower extremity is denied.

FINDINGS OF FACT

1. The Veteran's type 2 diabetes mellitus did not have its onset in service, was not shown within one year of separation from service, and is not otherwise related to service, to include conceded hazardous environmental exposure, nor was it caused or aggravated by any service-connected disability.      

2. The Veteran's peripheral neuropathy of the right lower extremity did not have its onset in service, was not shown within one year of separation from service, and is not otherwise related to service, to include conceded hazardous environmental exposure, nor was it caused or aggravated by any service-connected disability.      

3. The Veteran's peripheral neuropathy of the left lower extremity did not have its onset in service, was not shown within one year of separation from service, and is not otherwise related to service, to include conceded hazardous environmental exposure, nor was it caused or aggravated by any service-connected disability.    

CONCLUSIONS OF LAW

1. The criteria for service connection for type 2 diabetes mellitus have not been met.  38 U.S.C. §§ 1110, 1154(a),, 5107(b); 38 C.F.R. §§ 3.102, 3.159, 3.303, 3.310.  

2. The criteria for service connection for peripheral neuropathy of the right lower extremity have not been met.  38 U.S.C. §§ 1110, 1154(a), 5107(b); 38 C.F.R. §§ 3.102, 3.159, 3.303, 3.310.  

3. The criteria for service connection for peripheral neuropathy of the left lower extremity have not been met.  38 U.S.C. §§ 1110, 1154(a), 5107(b); 38 C.F.R. §§ 3.102, 3.159, 3.303, 3.310.  

REASONS AND BASES FOR FINDINGS AND CONCLUSIONS

The Veteran had verified active duty for training in the United States Army National Guard from August 1968 to December 1968.  He also had additional service in the Puerto Rico Army National Guard.  

This matter comes before the Board of Veterans' Appeals (Board) on appeal from an October 2014 rating decision by the Department of Veterans Affairs (VA) Regional Office (RO).  

This case was previously before the Board in January 2019 when it was remanded for additional development.  

In September 2020, the Board denied entitlement to service connection for a psychiatric disability and for peripheral neuropathy of the right and left lower extremity.  

In a November 2020 Order to Vacate, the Board vacated the September 2020 Board decision, finding that the Board failed to provide due process.

This case was most recently before the Board in August 2025 when it was remanded for additional development.  The Board's August 2025 decision also granted service connection for an acquired psychiatric disorder, to include posttraumatic stress disorder (PTSD).  Such was implemented in a December 2025 rating decision, combined with his service-connected traumatic brain injury (TBI), and rated 70 percent disabling, effective from January 30, 2014.  As the benefit sought has been granted, the matter is no longer on appeal and will not be addressed herein.  

Finally, in the August 2025 decision, the Board noted that inasmuch as the Veteran was seeking service connection for right and left lower extremity peripheral neuropathy due to his diabetes mellitus, the Board must determine whether service connection was warranted for his diabetes mellitus.  See Bailey v. Wilkie, 33 Vet. App. 188, 203 (2021); Long v. Wilkie, 33 Vet. App. 167, 174 (2020) (en banc); Morgan v. Wilkie, 31 Vet. App. 162 (2019).  Hence, the matter of entitlement to service connection for type 2 diabetes mellitus is before the Board and is adjudicated herein.  

Service Connection

Service connection may be granted for a disability resulting from a disease or injury incurred in or aggravated by active service.  See 38 U.S.C. § 1110; 38 C.F.R
 must determine whether service connection was warranted for his diabetes mellitus.  See Bailey v. Wilkie, 33 Vet. App. 188, 203 (2021); Long v. Wilkie, 33 Vet. App. 167, 174 (2020) (en banc); Morgan v. Wilkie, 31 Vet. App. 162 (2019).  Hence, the matter of entitlement to service connection for type 2 diabetes mellitus is before the Board and is adjudicated herein.  

Service Connection

Service connection may be granted for a disability resulting from a disease or injury incurred in or aggravated by active service.  See 38 U.S.C. § 1110; 38 C.F.R. § 3.303.  A veteran seeking compensation under these provisions must establish three elements: "(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."  Saunders v. Wilkie, 886 F.3d 1356, 1361 (Fed. Cir. 2018) (quoting Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004)).

Service connection may be established for disability that is proximately due to or the result of a service-connected disability.  38 C.F.R. § 3.310(a).  

Further, a disability which is aggravated by a service-connected disability may be service-connected to the degree that the aggravation is shown.  38 C.F.R. § 3.310; El-Amin v. Shinseki, 26 Vet. App. 136 (2013); Allen v. Brown, 7 Vet. App. 439 (1995).  

Proximate cause under 38 C.F.R. § 3.310(a) is defined as a cause that directly produces an event without which the event would not have occurred.  VAOPGCPREC 1-2017, at 9-10 (Jan. 6, 2017); see also Carter v. McDonough, 46 F.4th 1356, 1360 (Fed. Cir. 2022) (citing Ollis v. Shulkin, 857 F.3d 1338, 1344 (Fed. Cir. 2017)) (defining proximate cause in terms of foreseeability, so that legal responsibility is limited to causes which are so closely connected with the result).  

When there are potentially multiple causes of harm, an action is considered to be a proximate cause of the harm if it is a substantial factor in bringing about the harm and the harm would not have occurred but for the action.  The action just has to be a legal cause, it does not have to be the sole or even predominant cause.  Carter, 46 F.4th at 1360-61.  In essence, proximate cause requires that the event, injury or service-connected disability played a role in the development of the secondary condition.

A determination of proximate cause is one of fact, for determination by adjudication personnel.  See Walsh v. Wilkie, 32 Vet. App. 300, 303 (2020).

In March 2023, the United States Court of Appeals for the Federal Circuit (Federal Circuit) issued a decision that addressed the issue of causation in 38 U.S.C. § 1110.  Spicer v. McDonough, 61 F.4th 1360 (Fed. Cir. 2023).  The Federal Circuit explained that the phrase "resulting from" in the statute refers to "but-for" causation (which is broad, undisputedly broader than proximate causation) and is not limited to a single cause and effect, but rather contemplates multi-causal links, including action and inaction.  Spicer, 61 F.4th at 1363-64.  The Federal Circuit held secondary service connection is warranted where a nonservice-connected disability would have been less severe but-for a service-connected disability, either because there is an etiological link (to include worsening of functionality) between the two, or because the service-connected disability resulted in the inability to treat the nonservice-connected disability.  "Thus, for "aggravation of nonservice-connected disabilities" it is enough to show that "but for" the service-connected disability the incremental-increase in severity of a nonservice-connected disease or injury would not have occurred.

Finally, the Federal Circuit further held that 38 C.F.R. § 3.310(b), which addresses the aggravation prong of secondary service connection
1363-64.  The Federal Circuit held secondary service connection is warranted where a nonservice-connected disability would have been less severe but-for a service-connected disability, either because there is an etiological link (to include worsening of functionality) between the two, or because the service-connected disability resulted in the inability to treat the nonservice-connected disability.  "Thus, for "aggravation of nonservice-connected disabilities" it is enough to show that "but for" the service-connected disability the incremental-increase in severity of a nonservice-connected disease or injury would not have occurred.

Finally, the Federal Circuit further held that 38 C.F.R. § 3.310(b), which addresses the aggravation prong of secondary service connection, is inconsistent with 38 U.S.C. § 1110 and is therefore unlawful to the extent that VA applied it to reject the Veteran's theory of compensation.  Spicer, 61 F.4th at 1366.  

It is clear from the Federal Circuit's holding that causation and aggravation can be established without demonstrating a direct pathological link between the claimed disability and service-connected disabilities.

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

The Veteran seeks service connection for type 2 diabetes mellitus.  The Veteran has proffered no theory of entitlement to service connection for the disability.  

The Veteran's service treatment records are silent for complaints, findings, treatment, or diagnosis pertaining to diabetes.  November 1968 separation report of medical examination was normal on clinical evaluation, including urinalysis that was negative for sugar.  

The evidence of record shows the Veteran has been diagnosed with type 2 diabetes mellitus.  See October 2025 VA diabetes mellitus examination.  

The evidence of record includes an October 2025 VA opinion wherein it was noted there were no service treatment records while on service nor abnormal laboratory results that indicate the disability at that time.  Post-military private treatment records show the Veteran was diagnosed with diabetes in approximately 2007.  Due to a lack of evidence, a nexus was not established, and the examiner opined the claimed condition was less likely than not incurred in or caused by the claimed in-service injury, event or illness.  

In a January 2026 VA opinion, it was noted that the Veteran was exposed to environmental hazards during his service and the examiner conceded toxic exposure risk activity (TERA).  See also January 2026 TERA Memorandum (conceding TERA).  The Veteran's risk factors for his diabetes were indicated to include advanced age, hypertension, obesity, and hyperlipidemia.  The examiner stated no objective evidence could be found to allow for a determination of any connection to environmental hazards, including after review of medical literature.  It was indicated that the non-TERA risk factors far outweigh the TERA risk factors for the Veteran's diabetes.  It was therefore opined that the Veteran's diabetes was less likely than not caused by the indicated TERA, after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effect of all TERA of the Veteran.  

In December 2025 and January 2026 VA opinions, it was opined that the Veteran's diabetes was less likely than not proximately due to or the result of his service-connected tinnitus, Meniere's syndrome, and PTSD with TBI, to include the medication taken for each disability.  There was no evidence to determine objectively that the Veteran's diabetes worsened or was aggravated due to his service-connected disabilities, to include the medications taken for each disability.  

While the Veteran believes that his type 2 diabetes mellitus is related to his active military service, he is not competent to provide the medical etiology in this case.  The issue is medically complex, as it requires specialized medical education.  Jandreau v. Nicholson, 492 F.3d 1372, 1376-77 (Fed. Cir. 2007).  

There is no competent scientific or medical evidence of record to support the Veteran's contention that his diabetes is related to his active military service, to include as due to TERA.  The Veteran does not contend, and the record does not show, that his diabetes manifested during service or within a year of separation.  Medical records do not show diabetes until approximately at least 30 years following service.  All opinions of record are against a finding the Veteran's diabetes is related to his service, to include his TERA during service.  The October 2025 and January 2026 VA opinions were based on a review of the Veteran's claims file, provided by a medical professional competent to opine as to the etiology of the Veteran's diabetes, and supported by rationale.  

Accordingly, the Board finds the October 2025 and January 2026 VA opinions to be competent and
 as due to TERA.  The Veteran does not contend, and the record does not show, that his diabetes manifested during service or within a year of separation.  Medical records do not show diabetes until approximately at least 30 years following service.  All opinions of record are against a finding the Veteran's diabetes is related to his service, to include his TERA during service.  The October 2025 and January 2026 VA opinions were based on a review of the Veteran's claims file, provided by a medical professional competent to opine as to the etiology of the Veteran's diabetes, and supported by rationale.  

Accordingly, the Board finds the October 2025 and January 2026 VA opinions to be competent and persuasive.  Thus, service connection for diabetes is not available on a direct basis, to include as due to TERA during service.  

To the extent it may be contended that the Veteran's diabetes is secondary to his service-connected tinnitus, Meniere's syndrome, and/or PTSD with TBI, all opinions of record that addressed this theory of entitlement provided negative nexus opinions.  See December 2025, January 2026 VA opinions.  Taken together, the Board interprets these opinions to be cumulatively sufficient to find that the Veteran's diabetes is not secondary to his service-connected tinnitus, Meniere's syndrome, and/or PTSD with TBI, to include medication taken for each disability.  Such opinions were provided after a review of the Veteran's claims file, provided by a medical professional competent to opine as to the etiology of the Veteran's diabetes, and provided negative nexus opinions that were supported by rationale after review of the medical evidence.  There is no competent scientific or medical evidence of record to support that the Veteran's diabetes is secondary to a service-connected disability.   

In light of the foregoing, because the evidence is persuasively against the Veteran's claim and not in approximate balance, the benefit-of-the-doubt rule is not applicable, and therefore service connection for type 2 diabetes mellitus is not warranted.  See Lynch v. McDonough, 21 F.4th 776 (Fed. Cir. 2021) (en banc).  As such, service connection for type 2 diabetes mellitus must be denied.  

2. Entitlement to service connection for peripheral neuropathy of the right lower extremity.

3. Entitlement to service connection for peripheral neuropathy of the left lower extremity.

The Veteran contends that his right and left lower extremity peripheral neuropathy are secondary to his type 2 diabetes mellitus.  See August 2014 VA Form 21-526EZ.  

As indicated above, the Board notes that the RO has conceded exposure to environmental hazards during the Veteran's service, thereby conceding TERA exposure.  See also January 2026 TERA Memorandum (conceding TERA).  

The Veteran's service treatment records are silent for complaints, findings, treatment, or diagnosis pertaining to peripheral neuropathy of either lower extremity.  November 1968 separation report of medical examination was normal on clinical evaluation.  

The evidence of record shows the Veteran has been diagnosed with bilateral lower extremity diabetic peripheral neuropathy.  See January 2020 VA diabetic sensory-motor peripheral neuropathy.  

The evidence of record includes a January 2020 VA examination wherein it was indicated the disabilities were diagnosed in 2005.  After review of the Veteran's medical records, it was noted that the Veteran's service treatment records were silent for lower extremity peripheral neuropathy during service, or one year after separation.  There were no medical follow ups, or signs or symptoms associated with the condition.  The examiner stated that there was evidence in the medical literature that diabetes causes lower extremity diabetic peripheral neuropathy.  

In an October 2025 VA opinion, it was noted that there were no service treatment records while in service that showed complaint, evaluation, or treatment for lower extremity neuropathy.  Post-military private treatment records show the Veteran was diagnosed with the disabilities after 2000.  Due to a lack of evidence, a nexus was not established, and the examiner opined the claimed conditions were less likely than not incurred in or caused by the claimed in-service injury, event or illness.  

In a January 2026 VA opinion, it was noted that the Veteran was exposed to environmental hazards during his service and the examiner conceded TERA.  The Veteran's risk factors for his bilateral lower extremity peripheral neuropathy were indicated to included advanced age, hypertension, obesity, and type 2 diabetes mellitus.  The examiner stated there was no evidence in the medical literature allowing for a correlation between the Veteran's TERA and his bilateral lower extremity peripheral neuropathy.  The examiner opined that neuropathies are the most common complication of diabetes mellitus, affecting up to 50
, and the examiner opined the claimed conditions were less likely than not incurred in or caused by the claimed in-service injury, event or illness.  

In a January 2026 VA opinion, it was noted that the Veteran was exposed to environmental hazards during his service and the examiner conceded TERA.  The Veteran's risk factors for his bilateral lower extremity peripheral neuropathy were indicated to included advanced age, hypertension, obesity, and type 2 diabetes mellitus.  The examiner stated there was no evidence in the medical literature allowing for a correlation between the Veteran's TERA and his bilateral lower extremity peripheral neuropathy.  The examiner opined that neuropathies are the most common complication of diabetes mellitus, affecting up to 50 percent of patients with type 1 and type 2 diabetes mellitus.  The Veteran's bilateral lower extremity peripheral neuropathy was most likely due to his diabetes.  It was therefore opined that the Veteran's bilateral lower extremity peripheral neuropathy was less likely than not caused by the indicated TERA, after considering the total potential exposure through all applicable military deployments of the Veteran and the synergistic, combined effect of all TERA of the Veteran.  

In December 2025 and January 2026 VA opinions, it was opined that the Veteran's right and left lower extremity peripheral neuropathy were less likely than not proximately due to or the result of his service-connected tinnitus, Meniere's syndrome, and PTSD with TBI, to include the medication taken for each disability.  There was no evidence to determine objectively that the Veteran's right and left lower extremity peripheral neuropathy worsened or was aggravated due to his service-connected disabilities, to include the medications taken for each disability.  

While the Veteran believes that his bilateral lower extremity peripheral neuropathy is related to his active military service, he is not competent to provide the medical etiology in this case.  The issue is medically complex, as it requires specialized medical education.  Jandreau v. Nicholson, 492 F.3d 1372, 1376-77 (Fed. Cir. 2007).  

There is no competent scientific or medical evidence of record to support the Veteran's contention that his bilateral lower extremity peripheral neuropathy is related to his active military service, to include as due to TERA.  

In addition, the Veteran does not contend, and the record does not show, that his bilateral lower extremity peripheral neuropathy manifested during service or within a year of separation.  

Medical records do not show bilateral lower extremity peripheral neuropathy until approximately at least 30 years following service.  All opinions of record are against a finding the Veteran's bilateral lower extremity peripheral neuropathy is related to his service, to include his TERA during service.  January 2020, October 2025 and January 2026 VA opinions were based on a review of the Veteran's claims file, provided by a medical professional competent to opine as to the etiology of the Veteran's bilateral lower extremity peripheral neuropathy, and supported by rationale.  

Accordingly, the Board finds the January 2020, October 2025 and January 2026 VA opinions to be competent and persuasive.  Thus, service connection for bilateral lower extremity peripheral neuropathy is not available on a direct basis, to include as due to TERA during service.  

To the extent it may be contended that the Veteran's bilateral lower extremity peripheral neuropathy is secondary to his service-connected tinnitus, Meniere's syndrome, and/or PTSD with TBI, all opinions of record that addressed this theory of entitlement provided negative nexus opinions.  See December 2025, January 2026 VA opinions.  Taken together, the Board interprets these opinions to be cumulatively sufficient to find that the Veteran's bilateral lower extremity peripheral neuropathy is not secondary to his service-connected tinnitus, Meniere's syndrome, and/or PTSD with TBI, to include medication taken for each disability.  Such opinions were provided after a review of the Veteran's claims file, provided by a medical professional competent to opine as to the etiology of the Veteran's bilateral lower extremity peripheral neuropathy, and provided negative nexus opinions that were supported by rationale after review of the medical evidence. There is no competent scientific or medical evidence of record to support that the Veteran's bilateral lower extremity peripheral neuropathy is secondary to a service-connected disability.   

In light of the foregoing, because the evidence is persuasively against the Veteran's claim and not in approximate balance, the benefit-of-the-doubt rule is not applicable, and therefore service connection for bilateral lower extremity peripheral neuropathy is not warranted.  See Lynch v. McDonough, 21 F.4th 776 (Fed. Cir. 2021) (en banc).  As such, service connection for bilateral lower
 the Veteran's bilateral lower extremity peripheral neuropathy, and provided negative nexus opinions that were supported by rationale after review of the medical evidence. There is no competent scientific or medical evidence of record to support that the Veteran's bilateral lower extremity peripheral neuropathy is secondary to a service-connected disability.   

In light of the foregoing, because the evidence is persuasively against the Veteran's claim and not in approximate balance, the benefit-of-the-doubt rule is not applicable, and therefore service connection for bilateral lower extremity peripheral neuropathy is not warranted.  See Lynch v. McDonough, 21 F.4th 776 (Fed. Cir. 2021) (en banc).  As such, service connection for bilateral lower extremity peripheral neuropathy must be denied.  

To the extent the Veteran contends that his bilateral lower extremity peripheral neuropathy is secondary to his type 2 diabetes mellitus, the Board notes that the Veteran has not been awarded service connection for type 2 diabetes mellitus, and entitlement to service connection for bilateral lower extremity peripheral neuropathy secondary to such is not warranted.  

 

 

STEVEN D. REISS

Veterans Law Judge

Board of Veterans' Appeals

Attorney for the Board	J. Marley, 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.