Citation Nr: 1308724 Decision Date: 03/14/13 Archive Date: 03/25/13 DOCKET NO. 09-03 648 ) DATE ) ) On appeal from the Department of Veterans Affairs Regional Office in Chicago, Illinois THE ISSUES Entitlement to service connection for hypertension, to include as secondary to in-service exposure to herbicides or as secondary to service-connected diabetes mellitus, type II. REPRESENTATION Appellant represented by: Illinois Department of Veterans Affairs ATTORNEY FOR THE BOARD A. M. Clark, Counsel INTRODUCTION The Veteran served on active duty from September 1967 to April 1969. This current matter comes before the Board of Veterans' Appeals (BVA or Board) on appeal from rating decisions of the Department of Veterans Affairs (VA) Regional Office (RO) in Chicago, Illinois. Specifically, by an October 2007 rating action, the RO denied service connection for hypertension, on a direct basis and as secondary to the service-connected diabetes mellitus, type II. By an August 2008 rating decision, the RO denied service connection for hypertension, as secondary to in-service exposure to herbicides. The Veteran perfected a timely appeal. In his substantive appeal (VA Form 9), received in February 2009, the Veteran requested a hearing at the RO before a Veterans Law Judge (VLJ). In April 2012, the Veteran withdrew this hearing request. 38 C.F.R. § 20.704(e) (2012). In August 2012, the Board remanded this case for further development. Pursuant to that Remand, the RO was asked to request from the Veteran any identifying information and necessary authorization to obtain private treatment records and to provide him with an additional VA examination. The Board is satisfied there was substantial compliance with this Remand. Stegall v. West, 11 Vet. App. 268 (1998); Dyment v. West, 13 Vet. App. 141, 146-47 (1999). A January 2013 supplemental statement of the case was issued, and the case is once again before the Board. The Board notes that an April 2005 rating decision denied service connection claims for bilateral hearing loss and tinnitus, which was perfected for appeal by the Veteran. However, by a January 2009 rating decision, service connection for bilateral hearing loss and service connection for tinnitus was granted, which represents a full grant of those benefits sought. See Grantham v. Brown, 114 F.3d. 1156 (Fed. Cir. 1997). As the Veteran did not initiate an appeal of the ratings or effective dates assigned to those now service-connected disabilities, no issue regarding his hearing loss and tinnitus are in appellate status. In any event, however the issue of entitlement to an increased rating for bilateral hearing loss has been subsequently raised by the record. The agency of original jurisdiction (AOJ) has not adjudicated this issue. Therefore, the Board does not have jurisdiction over this claim, and it is referred to the AOJ for appropriate action. FINDINGS OF FACT 1. Hypertension is not recognized by VA as causally related to exposure to herbicide agents used in Vietnam. 2. The preponderance of the competent and credible evidence of record fails to establish that hypertension manifested in service or within one year of service discharge or that it is otherwise etiologically related to the Veteran's active service (including his in-service exposure to herbicides), and is not caused or aggravated by his service-connected diabetes mellitus, type II. CONCLUSION OF LAW Hypertension was not incurred or aggravated in service and is not related to the service-connected diabetes mellitus, type II. 38 U.S.C.A. §§ 1110, 5107 (West 2002); 38 C.F.R. §§ 3.102, 3.303, 3.307, 3.309, 3.310 (2012). REASONS AND BASES FOR FINDINGS AND CONCLUSION I. Duties to Assist and Notify As provided for by the Veterans Claims Assistance Act of 2000 (VCAA), VA has a duty to notify and assist claimants in substantiating a claim for VA benefits. 38 U.S.C.A. §§ 5100, 5102, 5103, 5103A, 5107, 5126 (West 2002); 38 C.F.R. §§ 3.102, 3.156(a), 3.159, 3.326(a) (2012). Proper notice from VA must inform the claimant and his representative, if any, prior to the initial unfavorable decision on a claim by the agency of original jurisdiction (AOJ) of any information and any medical or lay evidence not of record (1) that is necessary to substantiate the claim; (2) that VA will seek to provide; and (3) that the claimant is expected to provide. 38 U.S.C.A. § 5103(a); 38 C.F.R. § 3.159(b); Mayfield v. Nicholson, 444 F.3d 1328 (Fed. Cir. 2006); Pelegrini v. Principi, 18 Vet. App. 112 (2004); Quartuccio v. Principi, 16 Vet. App. 183 (2002). These notice requirements apply to all five elements of a service-connection claim (Veteran status, existence of a disability, a connection between the Veteran's service and the disability, degree of disability, and effective date of the disability). Dingess v. Nicholson, 19 Vet. App. 473 (2006). Information that a disability rating and an effective date for the award of benefits will be assigned if service connection is awarded must be included. Id. Here, in September 2006 the Veteran was notified via letter of the criteria for establishing service connection, the evidence required in this regard, and his and VA's respective duties for obtaining evidence. He was additionally notified of how VA determines disability ratings and effective dates if service connection is awarded. Further, neither the Veteran nor his representative has alleged prejudice with respect to notice, as is required. Shinseki v. Sanders, 129 S. Ct. 1696 (2009); Goodwin v. Peake, 22 Vet. App. 128 (2008); Hartman v. Nicholson, 483 F.3d 1311 (Fed. Cir. 2007); Dunlap v. Nicholson, 21 Vet. App. 112 (2007). None is found by the Board. Therefore, adequate notice was provided to the Veteran prior to the transfer and recertification of his case to the Board and complied with the requirements of 38 U.S.C.A. § 5103(a) and 38 C.F.R. § 3.159(b). Next, VA has a duty to assist a veteran in the development of the claim. This duty includes assisting him or her in the procurement of service treatment records and other pertinent records, and providing an examination when necessary. See 38 U.S.C.A. § 5103A (West 2002); 38 C.F.R. § 3.159 (2012). After a careful review of the file, the Board finds that all necessary development has been accomplished, and therefore appellate review may proceed without prejudice to the Veteran. See Bernard v. Brown, 4 Vet. App. 384 (1993). The RO has obtained the Veteran's service treatment records and VA outpatient treatment records. Additionally, he has submitted private treatment records. Significantly, neither the Veteran nor his representative has identified, and the record does not otherwise indicate, any additional existing evidence that is necessary for a fair adjudication of the claim that has not been obtained. VA examinations and opinions with respect to the issue on appeal were obtained in October 2007, December 2011, and September 2012. 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 remanded the claim in August 2012 so that an additional VA examination could be obtained which addressed all contentions raised by the Veteran to include whether his hypertension is directly related to, or associated with his active duty, to include his conceded in-service exposure to herbicides. The Board finds that the VA opinions together adequately address all of the Veteran's contentions and are adequate, as they are predicated on a full reading of the Veteran's claims file. They consider all of the pertinent evidence of record, the statements of the Appellant, and provide a sufficient rationale for the opinions stated, relying on and citing to the records reviewed. Accordingly, the Board finds that VA's duty to assist with respect to obtaining a VA examination or opinion with respect to the issue on appeal has been met. 38 C.F.R. § 3.159(c) (4). Hence, no further notice or assistance is required to fulfill VA's duty to assist in the development of the claim. Smith v. Gober, 14 Vet. App. 227 (2000), aff'd, 281 F.3d 1384 (Fed. Cir. 2002); Dela Cruz v. Principi, 15 Vet. App. 143 (2001); see also Quartuccio v. Principi, 16 Vet. App. 183 (2002). II. Service Connection Under the relevant laws and regulations, service connection may be granted for a disability resulting from disease or injury incurred in or aggravated by active service. 38 U.S.C.A. § 1110 (West 2002). Generally, the evidence 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. Shedden v. Principi, 381 F.3d 1163, 1166 -67 (Fed. Cir. 2004) (citing Hansen v. Principi, 16 Vet. App. 110, 111 (2002); Caluza v. Brown, 7 Vet. App. 498, 505 (1995), aff'd, 78 F.3d 604 (Fed. Cir. 1996) (table)). Continuity of symptomatology is required only where the condition noted during service (or in the presumptive period) is not, in fact, shown to be chronic, or where the diagnosis of chronicity may be legitimately questioned. When the fact of chronicity in service is not adequately supported, then a showing of continuity after discharge is required to support the claim. 38 C.F.R. § 3.303(b) (2012). The provisions of § 3.303(b), however, only apply to the list of disabilities identified under § 3.309(a). Walker v. Shinseki, ___ F.3d ___, No. 2011-7184, 2013 WL 628429 (Fed. Cir. Feb. 21, 2013). Service connection may be granted for any disease diagnosed after discharge from active duty when all the evidence, including that pertinent to service, establishes that the disease was incurred in service. 38 C.F.R. § 3.303(d) (2012). Service connection may also be established for a current disability on the basis of a presumption under the law that certain chronic diseases, such as hypertension, manifesting themselves to a certain degree within a certain time after service must have had their onset in service. 38 U.S.C.A. §§ 1112, 1113 and 1137; 38 C.F.R. §§ 3.303, 3.304, 3.307 and 3.309(a). Service connection for hypertension may be established based on a legal "presumption" by showing that it manifested itself to a degree of 10 percent or more within one year from the date of separation from service. 38 C.F.R. §§ 3.307, 3.309(a). In addition to the regulations cited above, service connection is warranted for a disability which is aggravated by, proximately due to, or the result of a service-connected disease or injury. 38 C.F.R. § 3.310 (2012). Establishing service connection on a secondary basis requires evidence sufficient to show (1) that a current disability exists and (2) that the current disability was either (a) proximately caused by or (b) proximately aggravated by a service-connected disability. Allen v. Brown, 7 Vet. App. 439, 448 (1995) (en banc). Where a service-connected disability aggravates a nonservice-connected condition, a veteran may be compensated for the degree of disability (but only that degree) over and above the degree of disability existing prior to the aggravation. Allen, 7 Vet. App. at 448. Service connection cannot be awarded on an aggravation basis without establishing a pre-aggravation baseline level of disability and comparing it to current level of disability. 71 Fed. Reg. 52744-47 (Sept. 7, 2006). Temporary or intermittent flare-ups of symptoms of a condition, alone, do not constitute sufficient evidence of aggravation unless the underlying condition worsened. Cf. Davis v. Principi, 276 F. 3d 1341, 1346-47 (Fed. Cir. 2002); Hunt v. Derwinski, 1 Vet. App. 292, 297 (1991). Finally, applicable regulations provide that a Veteran who served on active duty in Vietnam during the Vietnam era is presumed to have been exposed to Agent Orange or similar herbicide. 38 C.F.R. § 3.307(a)(1)(6)(iii). The specific statute pertaining to claimed Agent Orange exposure is 38 U.S.C.A. § 1116. Regulations issued pursuant thereto stipulate the diseases for which service connection may be presumed due to an association with exposure to herbicide agents. The diseases that are entitled to presumptive service connection based on herbicide exposure are listed in 38 C.F.R. § 3.309(e). This regulation was amended effective August 31, 2010, to add, in relevant part, atherosclerotic cardiovascular disease including coronary artery disease (including coronary spasm) and coronary bypass surgery; and stable, unstable and Prinzmetal's angina. 75 Fed. Reg. 53202 (August 31, 2010). Effective August 31, 2010, 38 C.F.R. § 3.309(e) provides that presumptive service connection based on Agent Orange exposure is available for the following diseases: AL amyloidosis; chloracne or other acneform disease consistent with chloracne; type 2 diabetes (also known as Type II diabetes mellitus or adult-onset diabetes); Hodgkin's disease; ischemic heart disease (including, but not limited to, acute, subacute, and old myocardial infarction; atherosclerotic cardiovascular disease including coronary artery disease (including coronary spasm) and coronary bypass surgery; and stable, unstable and Prinzmetal's angina); all chronic B-cell leukemias (including, but not limited to, hairy-cell leukemia and chronic lymphocytic leukemia); multiple myeloma; non-Hodgkin's lymphoma- Parkinson's disease; acute and subacute peripheral neuropathy; porphyria cutanea tarda; prostate cancer; respiratory cancers (cancer of the lung, bronchus, larynx, or trachea); soft-tissue sarcoma (other than osteosarcoma, chondrosarcoma, Kaposi's sarcoma, or mesothelioma). However, for purposes of this section, the term ischemic heart disease does not include hypertension or peripheral manifestations of arteriosclerosis such as peripheral vascular disease or stroke, or any other condition that does not qualify within the generally accepted medical definition of ischemic heart disease. 38 C.F.R. § 3.309(e), Note 3 (effective August 31, 2010). The Secretary of the Department of Veterans Affairs has determined that there is no positive association between exposure to herbicides and any other condition for which the Secretary has not specifically determined that a presumption of service connection is warranted. See Notice, 67 Fed. Reg. 42600-42608 (2002). Notwithstanding the foregoing, regulations also provide that service connection may be granted for any disease diagnosed after discharge, when all evidence, including that pertinent to service, establishes that the disability was incurred in service. 38 C.F.R. § 3.303(d); see also Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994). In other words, a presumption of service connection provided by law is not the sole method for showing causation in establishing a claim for service connection for disability due to herbicide exposure. See Stefl v. Nicholson, 21 Vet. App. 120 (2007) (holding that the availability of presumptive service connection for some conditions based on exposure to Agent Orange does not preclude direct service connection for other conditions based on exposure to Agent Orange). The Department of Defense ('DoD') has confirmed that the herbicide, Agent Orange, was used from April 1968 through July 1969 along the Korean Demilitarized Zone ('DMZ') to defoliate fields between the front line defensive positions and the south barrier fence. If it is determined that a veteran who served in Korea during this time period belonged to one of the units identified by DoD, then it is presumed that he or she was exposed to herbicides containing Agent Orange, and the presumptions outlined in 38 C.F.R. § 3.309(e) will apply. See MR21-1MR, Part IV, Subpart ii, Chapter 2, Section C; see also Veterans Benefits Administration Fact Sheet, distributed in September 2003. Here, the Veteran claims that his hypertension is the result of his service, to include exposure to herbicides, or in the alternative, is caused or aggravated by his service-connected diabetes mellitus, type II. Essentially, the Veteran asserts that service connection for hypertension is warranted under the theories of direct service connection, secondary service connection, and presumptive service connection. The Board will first address the Veteran's contentions that his hypertension is due to his exposure to herbicides. Records in his claim file reflect that the Veteran was exposed to herbicides in service while serving in Korea. In fact, an October 2007 rating decision awarded service connection for diabetes mellitus, type II, based on presumed exposure to herbicides. As such, exposure to herbicides is presumed. Despite his presumed exposure to an herbicide agent, presumptive service connection under 38 C.F.R. § 3.307(a)(6) is still not for application. Service connection is only warranted on this basis for a specific list of diseases set forth under 38 C.F.R. § 3.309(e). As the Veteran's claimed hypertension is not among those listed under 38 C.F.R. § 3.309(e) an award of presumptive service connection based on herbicide exposure is not warranted. With respect to presumptive service connection under 3.309(a), in light of the lack of medical evidence reflecting a diagnosis of hypertension within one year of the Veteran's separation from service, service connection on a presumptive basis for a chronic disorder is also not available. 38 C.F.R. § 3.309 (2012). Next, where the evidence does not warrant presumptive service connection, the United States Court of Appeals for the Federal Circuit has determined that an appellant is not precluded from establishing service connection with proof of direct causation. Combee v. Brown, 34 F.3d 1039 (Fed. Cir. 1994). However, the evidence does not show a causal relationship between the Veteran's hypertension and in-service herbicide exposure or to any other incident of active service. The Veteran's service treatment records are devoid of any instance of treatment for hypertension or elevated blood pressure readings, and his March 1969 separation examination reflects that his blood pressure was 128/72. The Board observes that the Veteran reported having experienced or currently experiencing high or low blood pressure in January 1968 and March 1969 reports of medical history. However, the medical records do not corroborate these allegations. The Veteran filed his claim for VA compensation for hypertension in August 2006. The earliest documented notation of hypertension presented in the post-service medical records associated with the Veteran's claims file is a December 2005 private treatment record reflecting a diagnosis of hypertension. The Veteran reported at his October 2007 VA examination that he was diagnosed with hypertension around 2003 and denied difficulty with blood pressure before then. See October 2007 VA examination report. The Board has considered the totality of the evidence and finds that the weight of the objective clinical evidence is against the Veteran's claim for service connection for hypertension. As previously noted, his service treatment records show normal blood pressure on separation from active duty, and there is no treatment for hypertension at any time during his active duty service. Following his discharge from service in April 1969, the available post-service medical records do not show documented indications of treatment for hypertension until 2005. According to the Veteran's own account, he was not diagnosed with hypertension until 2003 and did not have problems with his blood pressure before then. The Board has considered the Veteran's implied statements regarding onset of hypertension in or shortly after service with continuity of symptoms thereafter. In the absence of objective medical records establishing onset in service or continuity of symptomatology, a lay statement attesting to such may be sufficient in itself to establish a nexus with service if the statement is both credible and within the competence of the person presenting the statement to make. Buchanan v. Nicholson, 451 F.3d 1331, 1337 (Fed. Cir. 2006); Jandreau v. Nicholson, 492 F.3d 1372, 1377 (Fed. Cir. 2007); Davidson v. Shinseki, 581 F.3d 1313 (Fed. Cir. 2009). Certainly, the Veteran is competent to describe his own subjectively perceived symptoms, such as blood pressure issues, and their time of onset. However, his statements that he experienced onset and continuity of hypertension since service are not credible. The Veteran's account is contradicted by the documented medical record, which shows no such history of treatment for hypertension in service or for many years thereafter. To the contrary, the service treatment records document that the Veteran was seen on multiple occasions and sought treatment for other issues. This shows that he was not averse to seeking out medical treatment. Had he had been experiencing blood pressure problems in-service as he alleges, one would think he would have sought out care. Moreover, although he filed claims for bilateral hearing loss and tinnitus in December 2004, it was not until August 2006 that he filed a claim for hypertension. The fact that the Veteran was aware of the VA benefits system, sought out claims for other disabilities, but made no reference to his purported history of hypertension since service, weighs heavily against his credibility. Kahana v. Shinseki, 24 Vet. App. 428, 438 (2011) (Lance, J., concurring) (discussing the distinction between cases in which there is a complete absence of any evidence to corroborate or contradict the testimony, and cases in which there is evidence that is relevant either because it speaks directly to the issue or allows the Board as fact finder to draw a reasonable inference). Had the Veteran been experiencing hypertension at that time, there seems to be no reason why the Veteran would not have identified that disability. The value of the Veteran's assertions are additionally diminished, given that there is clinical evidence indicating that his blood pressure was normal at the time he left service. Continuity has not here been established, either through the competent evidence or through the Veteran's statements. Having determined that the Veteran's alleged clinical history regarding onset and continuity of hypertension since service is not credible, to the extent that he asserts on his own authority, based on his own personal knowledge of the particulars of his individual case, that his hypertension is related to service, although lay persons are competent to provide opinions on some medical issues [see Kahana v. Shinseki, 24 Vet. App. 428, 435 (2011)], the specific issue in this case falls outside the realm of common knowledge of a lay person as it involves making definitive clinical diagnoses based on knowledge of internal medicine. See Jandreau v. Nicholson, 492 F.3d 1372, 1377 n.4 (Fed. Cir. 2007) (Lay persons are not competent to diagnose degenerative joint and disc disease and spinal stenosis as these are not manifested by external but rather internal signs visible only through medical imaging technology and requiring expertise in radiographic analysis to diagnose). The Veteran's statements in this regard are thus entitled to no probative weight. The objective medical evidence of record does not establish a link between the Veteran's hypertension and his period of military service, to include his presumed herbicide exposure. After reviewing the Veteran's claims file and CPRS records a September 2012 VA examiner determined that it was less likely than not that the Veteran's hypertension had its onset during service or is otherwise related to service including his exposure to herbicides. She noted that the Veteran did not have hypertension during service or within one year of separation. She rationalized that Agent Orange or other herbicides are not known to cause hypertension and that most hypertension does not have an exact etiology and is therefore called essential hypertension. She opined that the Veteran has essential hypertension and that there is no way to ascertain the exact etiology. She noted that she or any physician would have to resort to mere speculation to render a precise opinion as to the etiology of his hypertension. There are no contradictory opinions of record. The Board has also considered the Veteran's statements asserting a nexus between his currently-diagnosed hypertension and active duty service. The Board reiterates that he is competent to report symptoms as they come to them through his senses. However, hypertension is not the type of disorder that a lay person can provide competent evidence on questions of etiology or diagnosis. Such competent evidence has been provided by the medical personnel who have examined the Veteran during the current appeal. Here, the Board attaches greater probative weight to the clinical findings than to his statements. Cartright v. Derwinski, 2 Vet. App. 24, 25 (1991) ("although interest may affect the credibility of testimony, it does not affect competency to testify"). Thus, the Board finds that the weight of the competent and credible evidence of record is against the Veteran's claim under the theory of direct service connection. The Board will next consider the Veteran's allegations of service connection on a secondary basis. Generally, in order to prevail on the issue of entitlement to secondary service connection, there must be: (1) evidence of a current disability; (2) evidence of a service-connected disability; and (3) nexus evidence, generally medical, establishing a connection between the service-connected disability and the current disability. Wallin v. West, 11 Vet. App. 509, 512 (1998). As to Wallin element (1), the medical evidence of record demonstrates that the Veteran is currently diagnosed with hypertension. With respect to Wallin element (2), it is undisputed that the Veteran is currently service-connected for diabetes mellitus, type II. Turning to crucial Wallin element (3), concerning a possible nexus between the Veteran's hypertension and his service-connected diabetes mellitus, type II, there are several nexus opinions of record. An October 2007 VA examiner, after a thorough review of the Veteran's VA claims file as well as an interview with and physical examination of the Veteran, opined that, given the Veteran's lack of microalbuminuria, his hypertension is not due to his diabetes. The VA examiner additionally noted that the Veteran's good control on his present medications meant that his hypertension had not been aggravated by his diabetes. In a February 2009 statement, a private treating physician noted that the Veteran had been his patient since 2005 and that he believed that the Veteran's high blood pressure "may be" directly linked to his diabetes, as patients who have diabetes are at high risk for associated comorbidity to include hypertension. He further noted that patients who have a history of type 2 diabetes have been known to be at increased risk for vascular complications. This February 2009 opinion is speculative in nature. Stegman v. Derwinski, 3 Vet. App. 228 (1992) (held that did little more than suggest a possibility that his illnesses might have been caused by service radiation exposure was insufficient to establish service connection). The probative value of this February 2009 statement is therefore limited. In an October 2011 opinion, the Veteran's private treating physician indicated that he had reviewed an RO decision, stating that the Veteran's hypertension was not due to diabetes mellitus because of a lack of microalbuminuria. He noted that while raised albumin in the urine may be seen with hypertension and diabetes as a result of their complication, this test does not determine etiology of hypertension. An etiological opinion of the private examiner was not provided, rather his statement is an attempt to discount the October 2007 VA examiner's opinion. A December 2011 VA examiner noted that the Veteran had had repetitively normal urine microalbumin/creatinine ratio over the years. She also noted that he additionally had sustained normal renal functions. She stated that the Veteran's blood pressure had been well controlled on medications. She noted that the medical literature states that urine microalbumin/creatinine ratio is the standard to determine if hypertension is secondary to diabetes mellitus. She noted that the October 2011 private treating physician's opinion is not supported by the medical literature. She indicated that the medical literature does conclude one can exclude diabetes as a cause of hypertension in the face of sustained normal microalbumin/creatine ratio and in the face of sustained normal serum creatinine (no renal failure). She concluded that, since the Veteran's blood pressure on medications had been under good control, there is no aggravation of his hypertension due to diabetes. In this case, the Board finds that the statements provided by the private physician are outweighed by the conclusions of the VA examiners in October 2007 and December 2011. As an initial matter, the February 2009 private treating physician's statement did not provide an opinion that is sufficient to establish service connection. Specifically, conclusions that the Veteran's high blood pressure "may be" directly linked to his diabetes is speculative and insufficient to establish a medical nexus. See Obert, 5 Vet. App. at 30 (1993) (medical opinion expressed in terms of 'may' also implies 'may or may not' and is too speculative to establish medical nexus). Moreover, although the private October 2011 private physician attempts to discount the October 2007 opinion, the December 2011 VA examiner directly addressed the inaccuracies of the October 2011 statement. The October 2007 and December 2011 VA examiners were able to examine the Veteran personally and review the Veteran's medical records. Rationale for their determinations was provided. The Board determines that the private treating physician's conclusions are outweighed by the observations of the VA examiners. The Board has also considered the statements made by the Veteran relating his hypertension to his service-connected diabetes mellitus and to service. In doing so, it must analyze the credibility and probative value of the evidence, account for the evidence that it finds to be persuasive or unpersuasive, and provide the reasons for its rejection of any material evidence favorable to the claimant. See Caluza v. Brown, 7 Vet. App. 498, 506 (1995), aff'd per curiam, 78 F.3d 604 (Fed. Cir.1996) (table); Gabrielson v. Brown, 7 Vet. App. 36, 39-40 (1994); Gilbert v. Derwinski, 1 Vet. App. 49, 57 (1990). Competency of evidence differs from weight and credibility. The former is a legal concept determining whether testimony may be heard and considered by the trier of fact, while the latter 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, 74 (1997); Layno v. Brown, 6 Vet. App. 465, 469 (1994); see also Cartright v. Derwinski, 2 Vet. App. 24, 25 (1991) ('although interest may affect the credibility of testimony, it does not affect competency to testify'). In this case, however, the Veteran is not competent to provide testimony regarding the etiology of his hypertension. Jandreau, 492 F.3d at 1377, n.4 ('Sometimes the layperson will be competent to identify the condition where the condition is simple, for example a broken leg, and sometimes not, for example, a form of cancer.'). It is true that he is competent to identify symptoms such as his blood pressure fluctuating. However, because hypertension is not the type of disorder that is diagnosed by unique and readily identifiable features, it does not involve a simple identification that a layperson is competent to make. The unsubstantiated statements regarding the claimed etiology of the Veteran's hypertension disorder are found to lack competency and therefore credibility and probative value. These VA opinions concerning etiology of the Veteran's hypertension are more persuasive than the Veteran's statements. The VA examiners conducted physical examinations of the Veteran, reviewed the entire claims file and medical history of the Veteran, and provided nexus opinions with supporting rationale. Thus, the Board finds that the VA examiners' opinions are more persuasive than the statements of the Veteran with respect to the etiology of his hypertension. Accordingly, the Board concludes that the preponderance of the evidence is against the entitlement to service connection for hypertension, to include as due to his in-service herbicide exposure or his service-connected diabetes mellitus. The Board acknowledges the Veteran, in February 2012, submitted copy of an internet article reflecting that diabetes and high blood pressure are closely related diseases. The Veteran additionally submitted a document in August 2007 which reflects that the Institute of Medicine of the National Academies found only limited or suggestive evidence of an association between exposure to Agent Orange and the subsequent development of hypertension. Medical treatise evidence can, in some circumstances, constitute competent medical evidence. Wallin v. West, 11 Vet. App. 509, 514 (1998); 38 C.F.R. § 3.159(a)(1) (competent medical evidence may include statements contained in authoritative writings such as medical and scientific articles and research reports and analyses). Similarly, medical treatise evidence could 'discuss [] generic relationships with a degree of certainty such that, under the facts of a specific case, there is at least a plausible causality based upon objective facts.' Mattern v. West, 12 Vet. App. 222, 229 (1999); Sacks v. West, 11 Vet. App. 314, 317 (1998), Libertine v. Brown, 9 Vet. App. 521 (1996). However, the articles submitted by the Veteran are of a general nature and does not contain any information or analysis specific to his case. Thus, this evidence is not persuasive as to the etiology of his hypertension. The Court has held on several occasions that medical evidence that is speculative, general or inconclusive in nature cannot support a claim. Obert v. Brown, 5 Vet. App. 30, 33 (1993); Tirpak v. Derwinski, 2 Vet. App. 609, 611 (1992). The Board has also considered a prior Board decision submitted by the Veteran to support his claim. That decision grants service connection for hypertension as due to in-service herbicide exposure. Nevertheless, the Board notes that prior Board decisions are nonprecedential. 38 C.F.R. § 20.1303 (2012). Further, of note, the submitted Board decision was authored in June 2007, over 5 years ago. When the Veteran's case was reviewed by the September 2012 VA examiner, she considered the most recent and up to date medical literature and determined that there was not a relationship between the Veteran's hypertension and diabetes mellitus, type II. In light of the above discussion, the Board concludes that the preponderance of the evidence is against the claim for service connection for hypertension and there is no doubt to be otherwise resolved. As such, the appeal is denied. ORDER Service connection for hypertension, to include as secondary to in-service exposure to herbicides or as secondary to service-connected diabetes mellitus, type II, is denied. ____________________________________________ THERESA M. CATINO Veterans Law Judge, Board of Veterans' Appeals Department of Veterans Affairs