Citation Nr: 1311456 Decision Date: 04/05/13 Archive Date: 04/19/13 DOCKET NO. 09-26 926 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Waco, Texas THE ISSUES 1. Entitlement to service connection for hypertension, to include as secondary to service-connected disabilities. 2. Entitlement to service connection for deep vein thrombosis to the right lower extremity (DVT), to include as secondary to service-connected disabilities. REPRESENTATION Appellant represented by: Texas Veterans Commission WITNESS AT HEARING ON APPEAL Veteran ATTORNEY FOR THE BOARD William Alan Nelson II, Associate Counsel INTRODUCTION The Veteran had active service from September 1963 to September 1975, with service in the Republic of Vietnam from August 1967 to August 1968. This case comes before the Board of Veterans' Appeals (Board) on appeal from an August 2008 rating decision of the Department of Veterans Affairs (VA) Regional Office (RO) in Waco, Texas. The Veteran appeared and provided testimony before the undersigned Acting Veterans Law Judge (VLJ) in June 2011. A transcript of the hearing has been associated with the claims file. The issues of service connection for hypertension and DVT, including as secondary to service-connected disabilities, were previously remanded by the Board in February 2013 to obtain an addendum VA medical opinion for hypertension and DVT. This was accomplished, and the claim was readjudicated in a February 2013 supplemental statement of the case (SSOC). For these reasons, the Board concludes that it may proceed with a decision at this time. See Dyment v. West, 13 Vet. App. 141, 146-47 (1999) (remand not required under Stegall v. West, 11 Vet. App. 268 (1998), where the Board's remand instructions were substantially complied with), aff'd, Dyment v. Principi, 287 F.3d 1377 (Fed. Cir. 2002). The Board must note that in reviewing this case the Board has not only reviewed the Veteran's physical claims file, but also his file on the "Virtual VA" system to insure a total review of the evidence. FINDINGS OF FACT 1. Hypertension is not an ischemic heart disease. 2. The Veteran did not sustain a cardiovascular injury or disease in service. 3. The Veteran did not experience chronic symptoms of hypertension in service. 4. Hypertension did not manifest to a compensable degree within one year of service separation. 5. Symptoms of hypertension have not been continuous since service separation. 6. The Veteran's hypertension is not related to active service. 7. The Veteran's hypertension is not causally related to or permanently worsened by any service-connected disability. 8. The Veteran did not experience chronic symptoms of DVT in service. 9. Symptoms of DVT have not been continuous since service separation. 10. The Veteran's DVT is not related to active service. 11. The Veteran's DVT is not causally related to or permanently worsened by any service-connected disability. CONCLUSIONS OF LAW 1. Hypertension was not incurred in active service and was not proximately due to or aggravated by a service-connected disability, and service connection for hypertension may not be presumed based on the one-year presumption for a chronic disease. 38 U.S.C.A. §§ 1110, 1112, 1131, 5103, 5103A, 5107 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.159, 3.303, 3.307, 3.309, 3.310, 4.104, Diagnostic Code (DC) 7101 (2012). 2. DVT was not incurred in active service and was not proximately due to or aggravated by a service-connected disability. 38 U.S.C.A. §§ 1110, 1112, 1131, 5103, 5103A, 5107 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.159, 3.303, 3.307, 3.309, 3.310 (2012). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS Duties to Notify and Assist The Veterans Claims Assistance Act of 2000 (VCAA) and implementing regulations imposes obligations on VA to provide claimants with notice and assistance. 38 U.S.C.A. §§ 5102, 5103, 5103A, 5107, 5126 (West 2002 & Supp. 2012); 38 C.F.R. §§ 3.102, 3.156(a), 3.326(a) (2012). The notice requirements of VCAA require VA to notify the claimant of what information or evidence is necessary to substantiate the claim; what subset of the necessary information or evidence, if any, the claimant is to provide; and what subset of the necessary information or evidence, if any, the VA will attempt to obtain. The Board notes that a "fourth element" of the notice requirement requesting the claimant to provide any evidence in the claimant's possession that pertains to the claim was removed from the language of 38 C.F.R. § 3.159(b)(1). See 73 Fed. Reg. 23,353-356 (April 30, 2008). The United States Court of Appeals for Veterans Claims (Court) issued a decision in the appeal of Dingess v. Nicholson, 19 Vet. App. 473 (2006), which held that the notice requirements of 38 U.S.C.A. § 5103(a) and 38 C.F.R. § 3.159(b) apply to all five elements of a service connection claim, including the degree of disability and the effective date of an award. Those five elements include: (1) veteran status; (2) existence of a disability; (3) a connection between a veteran's service and the disability; (4) degree of disability; and (5) effective date of the disability. In a timely January 2008 letter, the RO provided notice to the Veteran regarding what information and evidence is needed to substantiate a claim for service connection, as well as what information and evidence must be submitted by the Veteran and what evidence VA would obtain. The notice included provisions for disability ratings and for the effective date of the claim. The Board is also satisfied VA has made reasonable efforts to obtain relevant records and evidence, including affording VA examinations and obtaining opinions in August 2008, October 2011, September 2012, and February 2013. To that end, when VA undertakes to provide a VA examination or obtain a VA opinion, it must ensure that the examination or opinion is adequate. Barr v. Nicholson, 21 Vet. App. 303, 312 (2007). The Board finds that the VA opinions and findings obtained in this case are adequate. The VA nexus opinions provided consider all of the pertinent evidence of record, to include the statements of the Veteran, and provide a complete rationale for the opinions stated. Accordingly, the Board finds that VA's duty to assist with respect to obtaining a VA examination or opinion with respect to the issues of service connection for hypertension and DVT, including as secondary to service-connected disabilities, has been met. 38 C.F.R. § 3.159(c)(4). The Board is also satisfied VA has made reasonable efforts to obtain relevant records and evidence, including affording VA examinations. Specifically, the information and evidence that has been associated with the claims file includes the Veteran's service treatment records, post-service VA and private treatment records, VA examination reports that include nexus opinions, and the Veteran's statements. For these reasons, the Board finds that VA has fulfilled the duties to notify and assist the Veteran. Service Connection Laws and Regulations Service connection is warranted where the evidence of record establishes that a particular injury or disease resulting in disability was incurred in the line of duty in the active military service or, if pre-existing such service, was aggravated thereby. 38 U.S.C.A. § 1110; 38 C.F.R. § 3.303. The conditions at issue, hypertension and DVT, are "chronic diseases" listed under 38 C.F.R. § 3.309(a), therefore, 38 C.F.R. § 3.309(b) applies. See Walker v. Shinseki, No. 10-2634, 2011 WL 2020827 (Vet. App. May 25, 2011). In addition, service connection may also be granted on the basis of a post-service initial diagnosis of a disease, where the physician relates the current condition to the period of service. 38 C.F.R. § 3.303(d). Other specifically enumerated disorders, including hypertension, will be presumed to have been incurred in service if they manifested to a compensable degree within the first year following separation from active duty. 38 U.S.C.A. §§ 1101, 1112, 1113; 38 C.F.R. §§ 3.307, 3.309. Establishing service connection generally requires (1) medical evidence of a current disability; (2) medical or, in certain circumstances, lay evidence of in-service incurrence or aggravation of a disease or injury; and (3) medical evidence of a nexus between the claimed in-service disease or injury and the present disability. Shedden v. Principi, 381 F.3d 1163, 1167 (Fed. Cir. 2004). The Court has held that "Congress specifically limits entitlement for service-connected disease or injury to cases where such incidents have resulted in a disability. In the absence of proof of a present disability there can be no valid claim." Brammer v. Derwinski, 3 Vet. App. 223, 225 (1992); see also Rabideau v. Derwinski, 2 Vet. App. 141, 143-44 (1992). Where a veteran who served for ninety days or more during a period of war (or during peacetime service after December 31, 1946) develops certain chronic diseases, such as hypertension, to a degree of 10 percent or more within one year from separation from service, such diseases may be presumed to have been incurred in service even though there is no evidence of such disease during the period of service. This presumption is rebuttable by affirmative evidence to the contrary. See 38 U.S.C.A. §§ 1101, 1112, 1113, 1137 (West 2002 & Supp. 2011); 38 C.F.R. §§ 3.307, 3.309. Service connection may also be granted for a disability that is proximately due to or the result of a service-connected disability. See 38 C.F.R. § 3.310(a). When service connection is thus established for a secondary condition, the secondary condition shall be considered a part of the original condition. See 38 C.F.R. § 3.310(a); Harder v. Brown, 5 Vet. App. 183, 187 (1993). The controlling regulation has been interpreted to permit a grant of service connection not only for disability caused by a service-connected disability, but for the degree of disability resulting from aggravation of a non-service-connected disability by a service-connected disability. See Allen v. Brown, 7 Vet. App. 439, 448 (1995). Competency of evidence differs from weight and credibility. Competency is a legal concept determining whether testimony may be heard and considered by the trier of fact, while credibility is a factual determination going to the probative value of the evidence to be made after the evidence has been admitted. Rucker v. Brown, 10 Vet. App. 67 (1997); Layno v. Brown, 6 Vet. App. 465 (1994); Cartwright v. Derwinski, 2 Vet. App. 24 (1991) (although interest may affect the credibility of testimony, it does not affect competency to testify). A veteran is competent to report symptoms because this requires only personal knowledge, not medical expertise, as it comes to him through his senses. See Layno, 6 Vet. App. 465. The Board is charged with the duty to assess the credibility and weight given to evidence. Wensch v. Principi, 15 Vet. App. 362, 367 (2001); Wood v. Derwinski, 1 Vet. App. 190, 193 (1991). In weighing credibility, VA may consider interest, bias, inconsistent statements, bad character, internal inconsistency, facial plausibility, self interest, consistency with other evidence of record, malingering, desire for monetary gain, and demeanor of the witness. Caluza v. Brown, 7 Vet. App. 498 (1995). The Board may weigh the absence of contemporaneous medical evidence against the lay evidence in determining credibility, but the Board cannot determine that lay evidence lacks credibility merely because it is unaccompanied by contemporaneous medical evidence. Buchanan v. Nicholson, 451 F.3d 1331 (Fed. Cir. 2006). Generally, the degree of probative value which may be attributed to a medical opinion issued by a VA or private treatment provider takes into account such factors as its thoroughness and degree of detail, and whether there was review of the veteran's claims file. See Prejean v. West, 13 Vet. App. 444, 448-9 (2000). Also significant is whether the examining medical provider had a sufficiently clear and well-reasoned rationale, as well as a basis in objective supporting clinical data. See Bloom v. West, 12 Vet. App. 185, 187 (1999); Hernandez-Toyens v. West, 11 Vet. App. 379, 382 (1998); see also Claiborne v. Nicholson, 19 Vet. App. 181, 186 (2005) (rejecting medical opinions that did not indicate whether the physicians actually examined the veteran, did not provide the extent of any examination, and did not provide any supporting clinical data). The Court has held that a bare conclusion, even one reached by a health care professional, is not probative without a factual predicate in the record. Miller v. West, 11 Vet. App. 345, 348 (1998). Medical evidence that is speculative, general or inconclusive in nature cannot support a claim. See Obert v. Brown, 5 Vet. App. 30, 33 (1993); see also Beausoleil v. Brown, 8 Vet. App. 459, 463 (1996); Libertine v. Brown, 9 Vet. App. 521, 523 (1996). A physician's statement framed in terms such as "may" or "could" is not probative. See Warren v. Brown, 6 Vet. App. 4, 6 (1993). A significant factor to be considered for any opinion is the accuracy of the factual predicate, regardless of whether the information supporting the opinion is obtained by review of medical records or lay reports of injury, symptoms and/or treatment. See Harris v. West, 203 F.3d 1347, 1350-51 (Fed. Cir. 2000) (examiner opinion based on accurate lay history deemed competent medical evidence in support of the claim); Kowalski v. Nicholson, 19 Vet. App. 171, 177 (2005) (holding that a medical opinion cannot be disregarded solely on the rationale that the medical opinion was based on history given by the veteran); Reonal v. Brown, 5 Vet. App. 458, 461 (1993) (holding that the Board may reject a medical opinion based on an inaccurate factual basis). When all the evidence is assembled, VA is responsible for determining whether the evidence supports the claim or is in relative equipoise, with a veteran prevailing in either event, or whether a preponderance of the evidence is against a claim, in which case, the claim is denied. 38 U.S.C.A. § 5107(b); 38 C.F.R. § 3.102. The Board has reviewed all the evidence in the Veteran's claims file. Although the Board has an obligation to provide adequate reasons and bases supporting this decision, there is no requirement that the evidence submitted by a veteran or obtained on a veteran's behalf be discussed in detail. Rather, the Board's analysis below will focus specifically on what evidence is needed to substantiate the claims and what the evidence in the claims file shows, or fails to show, with respect to the claims. See Gonzales v. West, 218 F.3d 1378, 1380-81 (Fed. Cir. 2000); Timberlake v. Gober, 14 Vet. App. 122, 128-30 (2000). Service Connection for Hypertension The Veteran has claimed service connection for hypertension, which he essentially contends developed secondary to his service-connected diabetes. While this claim appears to be for secondary service connection, the Board will also consider whether hypertension is directly related to service. The Board finds that the Veteran served in the Republic of Vietnam. Based upon information obtained from the Veteran's service personnel and treatment records, exposure to herbicides during active service is presumed. See 38 C.F.R. § 3.307(a)(6)(iii) (2011) (a veteran who served in the Republic of Vietnam during the Vietnam era shall be presumed to have been exposed during such service to an herbicide agent). However, because the Veteran's hypertension is not listed among the Agent Orange-related diseases enumerated in 38 C.F.R. § 3.309(e), medical nexus may not be presumed as a matter of law. Specifically, the Agent Orange Act of 1991 requires that when the Secretary determines that a presumption of service connection based on herbicide exposure is not warranted for health outcomes, he must publish a notice of that determination, including an explanation of the scientific basis for the decision. The Secretary's determination must be based on consideration of reports of the National Academy of Sciences (NAS) and all other sound medical and scientific information and analysis available to the Secretary. 38 U.S.C.A. § 1116 (b) and (c). In July 2009, the NAS issued "Veterans and Agent Orange: Update 2008" (Update 2008). The attached notice explains a determination made by the Secretary, based upon Update 2008 and prior NAS reports, that a presumption of service connection based on exposure to herbicides in the Republic of Vietnam is not warranted for hypertension. Similarly, while several new diseases that are presumptive linked herbicide exposure were added recently, including ischemic heart disease, hypertension is specifically excluded from the meaning of "ischemic heart disease" as it is not a disease of the heart. VA Training Letter 10-04, Training Guide, p. 14. Hence the herbicide presumption is not applicable for hypertension. Notwithstanding the inapplicability of the Agent Orange presumptive service connection regulations, the Board is obligated to fully consider the Veteran's service connection claim on a direct basis. Combee v. Brown, 34 F.3d 1039, 1042 (Fed. Cir. 1994). The Board finds that the weight of the evidence demonstrates that the Veteran did not experience hypertension symptoms in service. Service treatment records identify no elevated diastolic blood pressure readings during service, and show only blood pressure (BP) readings that were within normal limits (i.e., the systolic reading was less than 140 millimeters of mercury and the diastolic reading was less than 90 millimeters of mercury); no diagnosis of hypertension is reflected in any examination or treatment record compiled in service. At the August 1975 service separation examination, the Veteran's BP was recorded as 110/68. Also, in the February 1969 service separation examination "Report of Medical History," the Veteran specifically denied a history or complaints of high blood pressure. Madden v. Gober, 125 F.3d 1477, 1481 (Fed. Cir. 1997) (upholding Board's finding that a veteran was not credible because lay evidence about a wound in service was internally inconsistent with other earlier lay statements that he had not received any wounds in service). The Veteran has not contended that he suffered from a cardiovascular injury or disease in service or that hypertension symptoms were chronic in service. Neither the separation examiner's summary of history nor clinical examination at service separation reflect any reported complaints, findings, or diagnosis of hypertension at service separation in September 1975. If there is no showing of a resulting chronic condition during service, then a showing of continuity of symptomatology after service is required to support a finding of chronicity. 38 C.F.R. § 3.303(b). The Board finds that the weight of the evidence demonstrates that the Veteran's hypertension did not manifest to a compensable degree within one year of service separation. A compensable rating is assigned for hypertension with diastolic pressure predominantly 100 or more, or; systolic pressure predominantly 160 or more, or; minimum evaluation for an individual with a history of diastolic pressure predominantly 100 or more who requires continuous medication for control. 38 C.F.R. § 4.104, DC 7101. There are no post-service treatment records documenting hypertension within one year of service separation. The first post-service evidence of hypertension is not dated until December 2005. The Board next finds that the weight of the evidence demonstrates that hypertension symptoms have not been continuous since service separation in September 1975. As indicated, the August 1975 service separation clinical examination did not reflect hypertension. Following service separation in September 1975, the evidence of record shows no complaints, diagnosis, or treatment for hypertension until 2005. The absence of post-service findings, diagnosis, or treatment for 30 years after service is one factor that tends to weigh against a finding of continuous hypertension symptoms after service separation. See Buchanan (holding that the Board may weigh the absence of contemporaneous medical evidence as one factor in determining credibility of lay evidence, but the Board cannot determine that lay evidence lacks credibility merely because it is unaccompanied by contemporaneous medical evidence); see also Maxson v. Gober, 230 F.3d 1330, 1333 (Fed. Cir. 2000) (the passage of many years between discharge from active service and the medical documentation of a claimed disability is one factor to consider as evidence against a claim of service connection). While the Veteran is competent to state that he had hypertension symptoms at any time, including in service, the Board finds that the Veteran has not contended or submitted any lay or medical evidence showing that hypertension symptoms have been continuous since service separation. See Charles v. Principi, 16 Vet. App. 370 (2002). During the June 2011 Board personal hearing, the Veteran testified that hypertension was not diagnosed until 2007. In a March 1999 VA dental examination, the Veteran reported no history of hypertension. See Harvey v. Brown, 6 Vet. App. 390, 394 (1994) (Board decision properly assigned more probative value to a private hospital record that included lay history that was made for treatment purposes than to subsequent statements made for compensation purposes). In VA treatment records dated from March 1999 to December 2005, the Veteran does not mention a cardiovascular injury or disease in service, chronic hypertension symptoms in service, or continuous hypertension symptoms since service separation. In a December 2005 VA treatment record, the Veteran denied any signs or symptoms of high blood pressure. See Harvey, 6 Vet. App. at 394. In a December 2005 private "Medical Examination Report," the Veteran reported no history of hypertension. Id. For treatment, the Veteran would be expected to give a full and accurate history to get good treatment. In none of these examinations for treatment does the Veteran mention a heart injury or disease in service, chronic hypertension symptoms in service, or continuous hypertension symptoms since service separation. See Cartright, 2 Vet. App. at 25; Pond v. West, 12 Vet. App. 341 (1991). While the Board has weighed and considered the absence of post-service complaints, findings, diagnosis, or treatment for hypertension after service prior to December 2005 as one factor that tends to weigh against a finding of either hypertension in service or continuous symptoms of hypertension after service separation, the Board has done so in the context of all the evidence of record, including multiple other factors, namely, contemporaneous in-service reports (history and complaints) by the Veteran, contemporaneous in-service clinical findings, and the Veteran's post-service statements indicating a lack of continuity of hypertension symptomatology made to health care professionals for treatment purposes. See Buchanan, 451 F.3d at 1337. The Board further finds that the weight of the competent evidence demonstrates that the Veteran's currently diagnosed hypertension is not related to active service. In the September 2012 VA hypertension opinion, which weighs against the Veteran's claim, the VA examiner opined that the Veteran's hypertension was less likely than not (less than a 50/50 probability) caused by or the result of active military service. The VA examiner reasoned that the Veteran's blood pressure was normal at service separation and normal during his job physical conducted every two years after separation from service. The VA examiner opined that hypertension did not begin until July 1999. The September 2012 VA hypertension opinion is of high probative value because it is based on a factually accurate history, as it appears the VA examiner was informed of the relevant evidence in this case that included the absence of complaints of hypertension in service as indicated by the service treatment records, and the absence of complaints of hypertension for many years after service as indicated by the post-service treatment records. The VA examiner relied on accurate facts, and gave a fully articulated opinion that is consistent with the accurate facts found in this case and is supported by a sound reasoning. There has similarly been no medical opinion of record advanced to even suggest that the Veteran's hypertension either began during or was otherwise caused by his military service. The Board finds that there is no competent or credible evidence of a relationship between the Veteran's current hypertension and his military service. The Veteran is also claiming that his hypertension is the direct result of his service-connected disabilities. To prevail on the issue of secondary service causation, generally, the record must show (1) evidence of a current disability, (2) evidence of a service-connected disability, and (3) medical nexus evidence establishing a connection between the current disability and the service-connected disability. Wallin v. West, 11 Vet. App. 509, 512 (1998); Reiber v. Brown, 7 Vet. App. 513, 516-17 (1995). The Veteran is service connected for diabetes. The Board finds that the weight of the evidence demonstrates that the claimed hypertension is not caused or aggravated by any service-connected disability. In the August 2008 VA hypertension opinion, the VA examiner opined that, based upon review of the current medical literature, there was no causal relationship between hypertension and diabetes. The VA examiner opined that the Veteran's hypertension was diagnosed years prior to the diagnosis of diabetes. In the October 2011 VA hypertension opinion, the VA examiner opined that, based upon review of the current medical literature, there was no causal relationship between hypertension and diabetes. The VA examiner opined that the medical records showed elevation of the Veteran's blood pressure since 1999 and was diagnosed with hypertension in 2005. The Veteran was not diagnosed with diabetes until July 2006. In the September 2012 VA hypertension opinion, the VA examiner opined that the Veteran's hypertension pre-dated the onset of diabetes. In the February 2013 VA addendum opinion, the VA examiner opined that the Veteran's hypertension was not caused by or aggravated by his service-connected diabetes. The VA examiner reasoned that the Veteran's hypertension diagnosis pre-dated the diagnosis of diabetes. The VA examiner further opined that the Veteran's hypertension was more likely aggravated by his age and that there is a normal progression of hypertension that is related to advancing age. The Board finds that the October 2011, September 2012, and February 2013 hypertension opinions are competent and probative medical evidence because they are factually accurate, as it appears the VA examiners reviewed the claims file and were informed of the relevant evidence in this case, the opinions are fully articulated, and are supported by a sound reasoning. The only evidence of record supporting the Veteran's claim is his own lay opinion that his currently diagnosed hypertension is related to his service-connected diabetes. Regarding the Veteran's statements as to the cause of the current hypertension, the Board recognizes that 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) (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 he was a layperson, conflicts with Jandreau v. Nicholson, 492 F.3d 1372 (Fed. Cir. 2007)). However, in this case, the cause of the Veteran's hypertension involves a complex medical etiological question because it deals with the origin and progression of the Veteran's hypertension, and because an internal and complex disease process such as hypertension is diagnosed primarily on clinical findings or comprehensive testing, and not on symptoms alone. The Veteran is competent to relate symptoms of hypertension that he experienced at any time, but is not competent to opine on whether there is a link between the current hypertension and active service or between the current hypertension and service-connected disabilities. Such diagnosis and opinion as to physiological nexus require specific medical knowledge and training. See Rucker, 10 Vet. App. at 74 (stating that a lay person is not competent to diagnose or make a competent nexus opinion about a disorder as complex as cancer). For these reasons, the Board finds that a preponderance of the lay and medical evidence that is of record weighs against the claim for service connection for hypertension, including as secondary to service-connected diabetes. Because the preponderance of the evidence is against the claim, the benefit of the doubt doctrine is not for application, and the claim must be denied. See 38 U.S.C.A. § 5107; 38 C.F.R. § 3.102. Service Connection for DVT The Veteran has claimed service connection for DVT, which he essentially contends developed secondary to his service-connected diabetes. While this claim appears to be for secondary service connection, the Board will also consider whether DVT is directly related to service. The Board finds that the weight of the evidence demonstrates that the Veteran did not experience DVT symptoms in service. Service treatment records are negative for any treatment for DVT or DVT symptoms. At the August 1975 service separation examination, the Veteran's vascular system was reported as normal. Neither the separation examiner's summary of history nor clinical examination at service separation reflect any reported complaints, findings, or diagnosis of DVT at service separation in September 1975. The Veteran has not contended that he suffered from a vascular injury or disease in service or that DVT symptoms were chronic in service. If there is no showing of a resulting chronic condition during service, then a showing of continuity of symptomatology after service is required to support a finding of chronicity. 38 C.F.R. § 3.303(b). The Board next finds that the weight of the evidence demonstrates that DVT symptoms have not been continuous since service separation in September 1975. As indicated, the August 1975 service separation clinical examination did not reflect DVT. Following service separation in September 1975, the evidence of record shows no complaints, diagnosis, or treatment for DVT until 2007. The absence of post-service findings, diagnosis, or treatment for 32 years after service is one factor that tends to weigh against a finding of continuous DVT symptoms after service separation. See Buchanan; see also Maxson, 230 F.3d at 1333. While the Veteran is competent to state that he had DVT symptoms at any time, including in service, the Board finds that the Veteran has not contended or submitted any lay or medical evidence showing that DVT symptoms have been continuous since service separation. See Charles. During the June 2011 Board personal hearing, the Veteran testified that DVT was not diagnosed until 2007. While the Board has weighed and considered the absence of post-service complaints, findings, diagnosis, or treatment for DVT after service prior to December 2007 as one factor that tends to weigh against a finding of either DVT in service or continuous symptoms of DVT after service separation, the Board has done so in the context of all the evidence of record, including multiple other factors, namely, contemporaneous in-service reports (history and complaints) by the Veteran, contemporaneous in-service clinical findings, and the Veteran's post-service statements indicating a lack of continuity of DVT symptomatology. See Buchanan, 451 F.3d at 1337. The Board further finds that the weight of the competent evidence demonstrates that the Veteran's currently diagnosed DVT is not related to active service. In the September 2012 VA DVT opinion, which weighs against the Veteran's claim, the VA examiner opined that the Veteran's DVT was less likely than not (less than a 50/50 probability) caused by or the result of active military service. The VA examiner reasoned that the Veteran's DVT was caused by a fracture of the acetabulum of the right hip in 2007; the VA examiner further reasoned that DVT is one of the complications of a fracture of the hip. The September 2012 VA DVT opinion is of high probative value because it is based on a factually accurate history, as it appears the VA examiner was informed of the relevant evidence in this case that included the absence of complaints of DVT in service as indicated by the service treatment records, and the absence of complaints of DVT for many years after service as indicated by the post-service treatment records. The VA examiner relied on accurate facts, and gave a fully articulated opinion that is consistent with the accurate facts found in this case and is supported by a sound reasoning. There has similarly been no medical opinion of record advanced to even suggest that the Veteran's DVT either began during or was otherwise caused by his military service. The Board finds that there is no competent or credible evidence of a relationship between the Veteran's current DVT and his military service. The Veteran is also claiming that his DVT is the direct result of his service-connected disabilities. To prevail on the issue of secondary service causation, generally, the record must show (1) evidence of a current disability, (2) evidence of a service-connected disability, and (3) medical nexus evidence establishing a connection between the current disability and the service-connected disability. Wallin, 11 Vet. App. at 512; Reiber, 7 Vet. App. at 16-17. The Veteran is service connected for diabetes. The Board finds that the weight of the evidence demonstrates that the claimed DVT is not caused or aggravated by any service-connected disability. In the September 2012 VA DVT opinion, which weighs against the Veteran's claim, the VA examiner opined that the Veteran's DVT was less likely than not (less than a 50/50 probability) caused by the Veteran's service-connected diabetes. The VA examiner reasoned that the Veteran's DVT was caused by a fracture of the acetabulum of the right hip in 2007. In the February 2013 VA addendum opinion, the VA examiner opined that the Veteran's DVT was not caused by or aggravated by his service-connected diabetes. The VA examiner reasoned that the Veteran's DVT was due to the femur fracture in 2007. The VA examiner further opined that the Veteran's DVT was not aggravated by the service-connected diabetes, because there was no history of recurrence of the DVT since it was treated initially. The Board finds that the September 2012 and February 2013 DVT opinions are competent and probative medical evidence because they are factually accurate, as it appears the VA examiners reviewed the claims file and were informed of the relevant evidence in this case, the opinions are fully articulated, and are supported by a sound reasoning. The only evidence of record supporting the Veteran's claim is his own lay opinion that his currently diagnosed DVT is related to his service-connected diabetes. Regarding the Veteran's statements as to the cause of the current DVT, the Board recognizes that lay witnesses may, in some circumstances, opine on questions of diagnosis and etiology. See Davidson, 581 F.3d at 1316. However, in this case, the cause of the Veteran's DVT involves a complex medical etiological question because it deals with the origin and progression of the Veteran's DVT, and because an internal and complex disease process such as DVT is diagnosed primarily on clinical findings or comprehensive testing, and not on symptoms alone. The Veteran is competent to relate symptoms of DVT that he experienced at any time, but is not competent to opine on whether there is a link between the current DVT and active service or between the current DVT and service-connected disabilities. Such diagnosis and opinion as to physiological nexus require specific medical knowledge and training. See Rucker at 74. For these reasons, the Board finds that a preponderance of the lay and medical evidence that is of record weighs against the claim for service connection for DVT, including as secondary to service-connected diabetes. Because the preponderance of the evidence is against the claim, the benefit of the doubt doctrine is not for application, and the claim must be denied. See 38 U.S.C.A. § 5107; 38 C.F.R. § 3.102. ORDER Service connection for hypertension is denied. Service connection for DVT is denied. ____________________________________________ T.D. JONES Acting Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs