Citation Nr: 21031353 Decision Date: 05/21/21 Archive Date: 05/21/21 DOCKET NO. 17-16 317 DATE: May 21, 2021 ORDER Entitlement to service connection for erectile dysfunction (ED), to include as secondary to service-connected diabetes mellitus, type II, is denied. Entitlement to service connection for hypertension, to include as secondary to herbicide exposure or service-connected coronary artery disease (CAD), is denied. Entitlement to service connection for macular degeneration, as secondary to service-connected diabetes mellitus, type II, is denied. Entitlement to service connection for kidney disease, to include as secondary to service-connected diabetes mellitus, type II, is denied. Entitlement to service connection for right upper extremity peripheral neuropathy, to include as secondary to service-connected diabetes mellitus, type II, is denied. Entitlement to service connection for left upper extremity peripheral neuropathy, to include as secondary to service-connected diabetes mellitus, type II, is denied. Entitlement to service connection for right lower extremity peripheral neuropathy, to include as secondary to service-connected diabetes mellitus, type II, is denied. Entitlement to service connection for left lower extremity peripheral neuropathy, to include as secondary to service-connected diabetes mellitus, type II, is denied. FINDINGS OF FACT 1. The preponderance of the evidence of record is against finding that the Veteran has, or has had at any time during the appeal, a current diagnosis of ED. 2. The Veteran's hypertension was not manifested in service or in the first post service year, and the preponderance of the evidence is against a finding that the Veteran's hypertension is related to his service, to include herbicide exposure, or caused or aggravated by service-connected disability. 3. The preponderance of the evidence of record is against finding that the Veteran's macular degeneration is caused or aggravated by service-connected diabetes mellitus, type II. 4. The Veteran's kidney disease was not manifested in service or in the first post service year, and the preponderance of the evidence is against finding that the Veteran's kidney disease is related to his service or caused or aggravated by service-connected disability. 5. The preponderance of the evidence of record is against finding that the Veteran's right upper extremity peripheral neuropathy is caused or aggravated by service-connected diabetes mellitus, type II. 6. The preponderance of the evidence of record is against finding that the Veteran's left upper extremity peripheral neuropathy is caused or aggravated by service-connected diabetes mellitus, type II. 7. The preponderance of the evidence of record is against finding that the Veteran's right lower extremity peripheral neuropathy is caused or aggravated by service-connected diabetes mellitus, type II. 8. The preponderance of the evidence of record is against finding that the Veteran's left lower extremity peripheral neuropathy is caused or aggravated by service-connected diabetes mellitus, type II. CONCLUSIONS OF LAW 1. The criteria for service connection for ED are not met. 38 U.S.C. §§ 1110, 1111, 5107(b); 38 C.F.R. §§ 3.102, 3.303(a). 2. The criteria for service connection for hypertension, to include as secondary to CAD, are not met. 38 U.S.C. §§ 1110, 1111, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.303(a), 3.310(a). 3. The criteria for service connection for macular degeneration, as secondary to service-connected diabetes mellitus, type II, are not met. 38 U.S.C. §§ 1110, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.310(a). 4. The criteria for service connection for kidney disease, to include as secondary to service-connected diabetes mellitus, type II, are not met. 38 U.S.C. §§ 1110, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.303(a), 3.310(a). 5. The criteria for service connection for right upper extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, are not met. 38 U.S.C. §§ 1110, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.310(a). 6. The criteria for service connection for left upper extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, are not met. 38 U.S.C. §§ 1110, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.310(a). 7. The criteria for service connection for right lower extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, are not met. 38 U.S.C. §§ 1110, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.310(a). 8. The criteria for service connection for left lower extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, are not met. 38 U.S.C. §§ 1110, 1131, 5107(b); 38 C.F.R. §§ 3.102, 3.310(a). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty in the United States Navy form January 1965 to January 1967, to include service in the territorial sea of the Republic of Vietnam. The Veteran testified at an April 2019 Board hearing before the undersigned Veterans Law Judge. A transcript of the hearing has been associated with the claims file. In the January 2020 Board decision, the Board denied entitlement to service connection for ED as secondary to service-connected diabetes mellitus, type II. The Veteran appealed this portion of the decision to the United States Court of Appeals for Veterans Claims (Court). The Court entered a joint motion for partial remand (JMPR) and vacated the January 2020 Board decision as to this issue. The issue is returned to the Board for appellate review. The remaining issues were remanded by the Board in the January 2020 decision for further development. The issues are returned to the Board for appellate review. Service Connection Service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by active service. 38 U.S.C.§ 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 - the so-called "nexus" requirement. Holton v. Shinseki, 557 F.3d 1362, 1366 (Fed. Cir. 2009) (quoting Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004)). Service connection may be granted for any disease initially diagnosed after discharge when all of the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d). In addition, service connection for certain chronic diseases may be established on a presumptive basis by showing that the condition manifested to a degree of 10 percent or more within one year from the date of separation from service. 38 U.S.C. §§ 1101, 1112, 1113, 1131, 1137; 38 C.F.R. §§ 3.307, 3.309(a); Fountain v. McDonald, 27 Vet. App. 258, 271-72 (2015). Although the disease need not be diagnosed within the presumption period, it must be shown, by acceptable lay or medical evidence, that there were characteristic manifestations of the disease to the required degree during that time. 38 U.S.C. §§ 1101, 1112, 1113; 38 C.F.R. §§ 3.307, 3.309(a). For the showing of chronic disease in service, there is required a combination of manifestations sufficient to identify the disease entity, and sufficient observation to establish chronicity at the time. If chronicity in service is not established, a showing of continuity of symptoms after discharge may support the claim. 38 C.F.R. §§ 3.303(b), 3.309; Walker v. Shinseki, 708 F.3d 1331 (Fed. Cir. 2013). Secondary service connection is warranted where a disability is proximately due to or the result of a service-connected disease or injury. 38 C.F.R. § 3.310(a). Briefly, the threshold legal requirements for a successful secondary service connection claim are: (1) Evidence of a current disability for which secondary service connection is sought; (2) a disability for which service connection has been established; and (3) competent evidence of a nexus between the two. The Veteran has provided an alternative theory of entitlement to service connection for hypertension, which is that his hypertension is due to herbicide exposure in service. The Board concedes that the Veteran was exposed to herbicides during his service in the waters of the Republic of Vietnam. The law provides that, if a veteran was exposed to an herbicide agent during service, certain listed diseases shall be service-connected if the requirements of 38 U.S.C.§ 1116 and 38 C.F.R. § 3.307(a)(6)(iii) are met, even though there is no record of such disease during service, provided further that the rebuttable presumption provisions of 38 U.S.C. § 1113 and 38 C.F.R. § 3.307(d) are also satisfied. The list of diseases afforded this presumption was expanded by August 2010 amendment to 38 C.F.R. § 3.309(e) to include chronic B-cell leukemias, Parkinson's disease, and ischemic heart disease. Ischemic heart disease includes, but is 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." This amendment is applicable to claims received by VA on or after August 31, 2010, and to claims pending before VA on that date, as well as certain previously denied claims. See 75 Fed. Reg. 52,202 (Aug. 31, 2010). When there is an approximate balance of positive and negative evidence regarding the merits of an issue material to the determination of the matter, the benefit of the doubt in resolving each such issue shall be given to the claimant. 38 U.S.C. § 5107(b); 38 C.F.R. § 3.102. When all of the evidence is assembled, VA is responsible for determining whether the evidence supports the claim or is in relative equipoise, with the appellant prevailing in either event, or whether a fair preponderance of the evidence is against the claim, in which case the claim is denied. Gilbert v. Derwinski, 1 Vet. App. 49, 55 (1990). 1. Entitlement to service connection for ED, to include as secondary to service-connected diabetes mellitus, type II, is denied. The Veteran asserts that he has symptoms of ED. See June 2016 VA 21-526EZ Fully Developed Claim. The question for the Board is whether the Veteran has a current disability that began during service or is at least as likely as not related to an in-service injury, event, or disease, or is secondary to a service-connected disability. The Board concludes that the Veteran does not have a current diagnosis of ED and has not had one at any time during the pendency of the claim or recent to the filing of the claim. 38 U.S.C. §§ 1110, 1131, 5107(b); Holton v. Shinseki, 557 F.3d 1363, 1366 (Fed. Cir. 2009); Romanowsky v. Shinseki, 26 Vet. App. 289, 294 (2013); McClain v. Nicholson, 21 Vet. App. 319, 321 (2007); 38 C.F.R. § 3.303(a), (d). The VA treatment records are silent for any complaints of, treatment for, or diagnosis of ED. The private treatment records are similarly silent for any complaints of, treatment for, or diagnosis of ED. An October 2018 private treatment record assessed the Veteran to have diabetes without complications. The August 2020 VA diabetes examiner indicated that the Veteran does not have conditions that are at least as likely as not due to diabetes mellitus. One of the conditions considered for this finding is ED. The Board acknowledges that the Veteran is competent to observe the symptoms of ED, however, he is not competent to provide a diagnosis or etiology of the symptoms. See Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (Whether lay evidence is competent and sufficient in a particular case is a fact issue to be addressed by the Board rather than a legal issue to be addressed by the Veterans Court.). As the medical evidence does not support the diagnosis of ED, the Board finds the medical records and the August 2020 VA diabetes examination to be persuasive. Consequently, the Board give more probative weight to the competent medical evidence. The existence of a current disability is the cornerstone of a claim for VA disability compensation. 38 U.S.C. § 1110; see Degmetich v. Brown, 104 F. 3d 1328, 1332 (1997) (holding that interpretation of sections 1110 and 1131 of the statute as requiring the existence of a present disability for VA compensation purposes cannot be considered arbitrary). Evidence must show that the Veteran currently has ED, or a similar disorder, for which benefits are being claimed. Because the evidence does not establish that the Veteran has ED or any other male reproductive system disability in any post-service treatment records, the Board finds that the Veteran is not entitled to service connection for ED. The claim must be denied. 2. Entitlement to service connection for hypertension, to include as secondary to herbicide exposure or service-connected CAD, is denied. The Veteran asserts that he is entitled to service connection for hypertension on a direct and secondary basis. However, as outlined below, the preponderance of the evidence of record demonstrates that the Veteran's hypertension did not manifest during, within the year following, as a result of active service, was not caused by herbicide exposure, and was not caused or aggravated by a service-connected disability. As such, service connection cannot be established on a direct or secondary basis. The December 1966 service treatment record (STR) separation examination shows the Veteran to have normal blood pressure at 132/88. In a January 2012 private treatment record, the medical provider indicated the Veteran has a diagnosis of hypertension. The August 2020 VA examiner opined that the Veteran's hypertension is less likely than not caused by service. The examiner reasoned that his hypertension is a normally occurring benign and essential type of hypertension that first occurred "long after service with no evidence during service" that hypertension was either occurring during service or would later develop due to any in-service occurrence. The examiner also opined that the Veteran's hypertension is less likely than not secondary to his service-connected coronary artery disease (CAD). The examiner reasoned that CAD occurred after the Veteran's development of hypertension. The examiner stated there is no evidence to show aggravation by either the heart disorder or the surgical history that would aggravate the hypertension. The examiner stated that a September 2019 echocardiogram definitively shows that the Veteran's CAD does not affect or aggravate hypertension. Based on the foregoing, there is no evidence that the Veteran's hypertension was manifested in service or to a compensable degree in the first year following his separation from service. Consequently, service connection for hypertension on the basis that such became manifest in service and persisted, or on a presumptive basis (as a chronic disease under 38 U.S.C. § 1112), is not warranted. Notably, the Veteran has not submitted competent evidence to show that he has suffered from hypertension continuously since service. See 38 C.F.R. § 3.303(b); Savage v. Gober, 10 Vet. App. 488, 495-96 (1997). There is also no evidence that the Veteran's hypertension is otherwise related to service. The Veteran's post-service private treatment records are silent for an opinion relating his hypertension to service. The only competent evidence in the record that addresses this question is the August 2020 VA medical opinion, which stated that the Veteran's hypertension was not related to his service. As there is no other evidence to the contrary, and the August 2020 VA medical opinion was based on a full review of the record as well as an interview and examination of the Veteran, the Board finds it persuasive. As to the assertion of herbicide exposure, hypertension is not listed among the diseases enumerated under 38 C.F.R. § 3.309(e); consequently, the herbicide agent presumptive provisions of 38 U.S.C. § 1116 do not apply. See also 75 Fed. Reg. 52,202 (Aug. 31, 2010) (explaining that since the term, "ischemic heart disease" refers only to heart disease; it does not include hypertension or peripheral manifestations of arteriosclerosis such as peripheral vascular disease or stroke). The United States Court of Appeals for the Federal Circuit has nevertheless determined that a claimant who suffers from a disability that is not listed among those for which presumptive service is afforded based on exposure to Agent Orange is not precluded from establishing service connection for such disability as due to Agent Orange exposure with proof of direct causation. Combee v. Brown, 34 F.3d 1039, 1042 (Fed. Cir. 1994). There is, as previously discussed, no competent evidence in the record of a possible nexus between the Veteran's hypertension and his service, to include Agent Orange exposure. Also, there is no evidence that the Veteran's hypertension was caused or aggravated by service-connected CAD. The post-service treatment records are silent for an opinion stating that his hypertension is caused or aggravated by CAD. The only competent evidence in the record that addresses secondary service connection is the August 2020 VA medical opinion, which stated that the Veteran's hypertension is not affected or aggravated by service-connected CAD. As there is no other evidence to the contrary, and the August 2020 VA medical examination and opinion is adequate, the Board finds it persuasive. Further, the Veteran's own statements relating his hypertension to service or a service-connected disability are not competent evidence, as he is a layperson and lacks the training to provide adequate opinion regarding medical etiology. Specifically, the Veteran lacks the training to opine whether hypertension, in the absence of credible evidence of continuity, as here, is related to an incident in service, to include exposure to herbicide agents, or is secondary to CAD. See Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (Whether lay evidence is competent and sufficient in a particular case is a fact issue to be addressed by the Board rather than a legal issue to be addressed by the Veterans Court). Also, hypertension is a disease of the vascular system, and the record does not show that the Veteran has training or education in this medical field; therefore, lay evidence of the etiology is not competent nexus evidence as it is not capable of lay observation. See Barr v. Nicholson, 21 Vet. App. 303, 307-08 (2007); Layno v. Brown, 6 Vet. App. 465, 469-70. Thus, the Veteran is not competent or qualified, as a layperson, to render an opinion on medical causation. In light of the foregoing, the Board concludes that the preponderance of the evidence is against the Veteran's claim of entitlement to service connection for hypertension. Accordingly, it must be denied. 3. Entitlement to service connection for macular degeneration, to include as secondary to service-connected diabetes mellitus, type II, is denied. The Veteran asserts that he is entitled to service connection for macular degeneration on a secondary basis. However, as outlined below, the preponderance of the evidence of record demonstrates that the Veteran's macular degeneration is not caused or aggravated by service-connected diabetes. As such, service connection cannot be established on a secondary basis. On the August 2020 VA examination, the examiner opined that the Veteran's macular degeneration is less likely than not secondary to his service-connected diabetes. The examiner reasoned that medical literature shows that exudative macular degeneration and diabetes are two separate and distinct disease processes which develop and exist independently of one another. The examiner explained that diabetes is a disease of the endocrine system and macular degeneration is one of senility. Based on the foregoing, the Board concludes that there is no evidence that the Veteran's macular degeneration was caused or aggravated by service-connected diabetes. The August 2020 VA examiner reasoned that medical literature shows that the Veteran's macular degeneration and diabetes are two separate and distinct disease processes that are independent of one another. As there is no other evidence to the contrary, and the August 2020 VA medical opinion was based on a review of the record as well as an interview and examination of the Veteran, the Board finds it persuasive. Consequently, service connection for macular degeneration on the basis that such is caused or aggravated by a service-connected disability, is not warranted. Further, the Veteran's own statements relating his macular degeneration to a service-connected disability are not competent evidence, as he is a layperson and lacks the training to provide adequate opinion regarding medical etiology. Specifically, the Veteran lacks the training to opine whether macular degeneration is caused or aggravated by a service-connected disability. See Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (Whether lay evidence is competent and sufficient in a particular case is a fact issue to be addressed by the Board rather than a legal issue to be addressed by the Veterans Court). Also, macular degeneration is a disease of the visual system, and the record does not show that the Veteran has training or education in this medical field; therefore, lay evidence of the etiology is not competent nexus evidence as it is not capable of lay observation. See Barr v. Nicholson, 21 Vet. App. 303, 307-08 (2007); Layno v. Brown, 6 Vet. App. 465, 469-70. Thus, the Veteran is not competent or qualified, as a layperson, to render an opinion on medical causation. In light of the foregoing, the Board concludes that the preponderance of the evidence is against the Veteran's claim of entitlement to service connection for macular degeneration on a secondary basis. Accordingly, it must be denied. 4. Entitlement to service connection for kidney disease, to include as secondary to service-connected diabetes mellitus, type II, is denied. The Veteran asserts that he is entitled to service connection for kidney disease on a direct and secondary basis. However, as outlined below, the preponderance of the evidence of record does not demonstrate that the Veteran's kidney disease manifested during, within the year following, or as a result of active service, or that it is caused or aggravated by a service-connected disability. As such, service connection cannot be established on a direct or secondary basis. The STRs show no complaints or treatment for a kidney disorder. In a January 2012 private treatment record, the medical provider indicated the Veteran has a diagnosis of renal insufficiency. In a March 2012 private treatment record, the medical provider indicated the Veteran had a diagnosis of chronic kidney disease. In an October 2012 private treatment discharge diagnoses list, the medical provider indicates the Veteran has chronic renal insufficiency. In a September 2015 private treatment record, the current diagnosis list included chronic kidney disease. In a September 2015 VA treatment record, the medical provider discussed discontinuing the Veteran's medication in view of renal insufficiency. In a June 2017 private treatment record, the ongoing past medical history lists the Veteran having chronic kidney disease. In an October 2019 private treatment record, the records show a history of renal insufficiency. On the August 2020 VA examination, the examiner opined that the Veteran's kidney disorder is less likely than not caused by service. The examiner reasoned that the Veteran has normal renal functioning and the previous decrease in function is due to medication effects. The examiner stated that when medication adjustments were made, the renal functioning showed normal findings and there is thus no renal impairment. The examiner stated that previous laboratory findings were due to previous medication effects only (ACE inhibitor effects and diuretics). None of the medications were related to the Veteran's diabetes. Based on the foregoing, the Board concludes that there is no evidence that the Veteran's kidney disease was manifested in service or to a compensable degree in the first year following his separation from service. Consequently, service connection for kidney disease on the basis that such became manifest in service and persisted, or on a presumptive basis (as a chronic disease under 38 U.S.C. § 1112), is not warranted. Notably, the Veteran has not submitted competent evidence to show that he has suffered from a kidney disease continuously since service. See 38 C.F.R. § 3.303(b); Savage v. Gober, 10 Vet. App. 488, 495-96 (1997). There is also no evidence that the Veteran's kidney disease is otherwise related to service. The Veteran's post-service private and VA treatment records are silent for an opinion relating his kidney disability to service. The only competent evidence in the record that addresses this question is the August 2020 VA medical opinion, which stated that the Veteran's kidney disease was not related to his service. As there is no other evidence to the contrary, and the August 2020 VA medical opinion was based on a full review of the record as well as an interview and examination of the Veteran, the Board finds it persuasive. Also, there is no evidence that the Veteran's kidney disease was caused or aggravated by service-connected diabetes. The post-service treatment records are silent for an opinion stating that kidney disease is caused or aggravated by diabetes. The only competent evidence in the record that addresses secondary service connection is the August 2020 VA medical opinion, which stated that the Veteran's renal insufficiency was not caused by diabetes, but was caused by prescribed medication (not related to diabetes) and has resolved by adjustments to the medication. As there is no other evidence to the contrary, and the August 2020 VA medical opinion was based on a full review of the record as well as an interview and examination of the Veteran, the Board finds it persuasive. Further, the Veteran's own statements relating his kidney disease to service or a service-connected disability are not competent evidence, as he is a layperson and lacks the training to provide adequate opinion regarding medical etiology. Specifically, the Veteran lacks the training to opine whether kidney disease or renal insufficiency, in the absence of credible evidence of continuity, as here, is related to an incident in service or a service-connected disability. See Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (Whether lay evidence is competent and sufficient in a particular case is a fact issue to be addressed by the Board rather than a legal issue to be addressed by the Veterans Court). Also, kidney disease is a disease of the renal system, and the record does not show that the Veteran has training or education in this medical field; therefore, lay evidence of the etiology is not competent nexus evidence as it is not capable of lay observation. See Barr v. Nicholson, 21 Vet. App. 303, 307-08 (2007); Layno v. Brown, 6 Vet. App. 465, 469-70. Thus, the Veteran is not competent or qualified, as a layperson, to render an opinion on medical causation. In light of the foregoing, the Board concludes that the preponderance of the evidence is against the Veteran's claim of entitlement to service connection for a kidney disease. Accordingly, it must be denied. 5. Entitlement to service connection for right upper extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, is denied. 6. Entitlement to service connection for left upper extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, is denied. 7. Entitlement to service connection for right lower extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, is denied. 8. Entitlement to service connection for left lower extremity peripheral neuropathy, as secondary to service-connected diabetes mellitus, type II, is denied. The Veteran asserts that he is entitled to service connection for bilateral upper and bilateral lower extremity peripheral neuropathy on a secondary basis. However, as outlined below, the preponderance of the evidence of record demonstrates that the Veteran's bilateral upper and lower extremity peripheral neuropathy is not caused or aggravated by service-connected diabetes. As such, service connection cannot be established on a secondary basis. In a September 2015 VA treatment record, the medical provider assessed the Veteran to have diabetes complicated with neuropathy. On the August 2020 VA diabetic peripheral neuropathy examination, the examiner indicated the Veteran has a diagnosis of peripheral neuropathy versus radiculopathy from severe spinal stenosis. The examiner described the history of the Veteran's diabetic peripheral neuropathy as decreased sensation and shooting radiculopathy pain due to spinal condition. The examiner indicated the other symptom the Veteran experiences is shooting radicular pain down the right and left legs. The examiner indicated the Veteran does not have upper or lower extremity diabetic peripheral neuropathy. The examiner remarked that review of present evidence, history, and physical evaluation does not show diabetes related peripheral neuropathy. The examiner stated that that it is instead likely the symptoms and findings are congruent with severe spinal stenosis, which is untreated. The August 2020 VA examiner opined that the Veteran's bilateral upper and lower extremity peripheral neuropathy is less likely than not caused or aggravated by service-connected diabetes. The examiner reasoned that the examination does not show to a 50 percent probability that his minor decreased sensation is due to diabetes. The examiner stated that given normal vibration sense and presence of severe spinal stenosis and the noted gait abnormalities, there is no objective findings that would show the Veteran's diabetes has caused or aggravated functioning of the peripheral nerves of the upper and lower extremities, even though there is a long history and severity of the diabetes. Based on the foregoing, the Board finds that the Veteran's symptoms of peripheral neuropathy are not caused or aggravated by service-connected diabetes. The August 2020 VA examiner found that the Veteran does not have a diagnosis of bilateral upper or bilateral lower extremity peripheral neuropathy, but experiences radicular pain due to a non-service-connected low back disorder. As the August 2020 VA medical opinion was based on a review of the record as well as an interview and examination of the Veteran, the Board finds it persuasive. Consequently, service connection for bilateral upper and bilateral lower extremity radiculopathy on the basis that such is caused or aggravated by a service-connected disability is not warranted. The Board acknowledges September 2015 private treatment record indicating that the Veteran has a diagnosis of diabetic peripheral neuropathy, however this treatment note did not refer to the low back disorder, appear to be a full examination, include testing, or contain any rationale for this conclusion. Therefore, the Board finds the September 2015 finding to be less persuasive than the fully reasoned August 2020 VA examination. Further, the Veteran's own statements relating his peripheral neuropathy symptoms to a service-connected disability are not competent evidence, as he is a layperson and lacks the training to provide adequate opinion regarding medical etiology. Specifically, the Veteran lacks the training to opine whether his peripheral neuropathy symptoms are caused or aggravated by a service-connected disability. See Jandreau v. Nicholson, 492 F. 3d 1372 (Fed. Cir. 2007) (Whether lay evidence is competent and sufficient in a particular case is a fact issue to be addressed by the Board rather than a legal issue to be addressed by the Veterans Court). Also, peripheral neuropathy is a disease of the nervous system, and the record does not show that the Veteran has training or education in this medical field; therefore, lay evidence of the etiology is not competent nexus evidence as it is not capable of lay observation. See Barr v. Nicholson, 21 Vet. App. 303, 307-08 (2007); Layno v. Brown, 6 Vet. App. 465, 469-70. Thus, the Veteran is not competent or qualified, as a layperson, to render an opinion on medical causation. In light of the foregoing, the Board concludes that the preponderance of the evidence is against the Veteran's claims of entitlement to service connection for bilateral upper and bilateral lower extremity peripheral neuropathy. Accordingly, they must be denied. Caroline B. Fleming Veterans Law Judge Board of Veterans' Appeals Attorney for the Board M. Thompson, Associate 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.