Citation Nr: 21064746 Decision Date: 10/21/21 Archive Date: 10/21/21 DOCKET NO. 05-06 797 DATE: October 21, 2021 REMANDED Entitlement to service connection for hypertension is remanded. REASONS FOR REMAND The Veteran served on active duty from December 1966 to August 1974. He died in May 2016. The Appellant is his surviving spouse. The Agency of Original Jurisdiction (AOJ) has granted her request for substitution. In February 2019, the Board most recently remanded this claim for additional development. Entitlement to service connection for hypertension is remanded. In the February 2019 remand, the Board requested that a VA examination be procured to determine whether the Veteran's hypertension was related to active duty service, to include herbicide agent exposure. Although the AOJ procured a VA examination to specifically address this question, the Board finds that the current evidence of record is insufficient to adequately adjudicate the question of whether the Veteran's hypertension was caused or aggravated by his service-connected diabetes mellitus, type II (DMII) and additional development is required. Notably, to address secondary service connection, the Veteran was afforded multiple VA examinations and medical opinions. In August 2006, a VA examiner diagnosed the Veteran with hypertension (with an onset of 2004) and opined that it was less likely than not caused by or a result of DMII. The examiner explained that, in the absence of renal dysfunction, DMII was not considered a cause of hypertension. The examiner, however, also opined that, while DMII did not cause hypertension, it was more likely than not that DMII would aggravate HTN because DMII accelerated arteriosclerosis increasing vascular resistance. Thereafter, in September 2009, the Veteran's VA physician provided an opinion indicating that hypertension was at least as likely as not aggravated by his service-connected DMII because DMII was associated with earlier and extensive development of atherosclerosis. The physician explained further that hyperinsulinemia damages the vascular endothelium. In May 2013, the Veteran underwent another VA examination to assess secondary service connection. The examiner rendered a negative nexus opinion and explained that the onset of the Veteran's hypertension was unclear (whether before or after DMII) and the Veteran did not have diabetic nephropathy or microalbuminuria at the time he was treated for hypertension. The examiner explained further that hypertension was a de novo condition and, in the absence of renal dysfunction caused by DMII, it could not be stated that hypertension was caused by DMII. The examiner noted the July 2006 VA examination that indicated that DMII could aggravate hypertension because it accelerated atherosclerosis. The examiner indicated, however, that there was not enough information about hypertension at the time it was diagnosed and, while aggravation was theoretically possible, the Veteran did not have renal dysfunction and the course of hypertension could be variable whether accompanied by DMII or not. The examiner, therefore, concluded that he could not speculate as to the degree of theoretical aggravation of hypertension due to DMII. In November 2018, the AOJ most recently procured a VA medical opinion to address secondary service connection. The examiner rendered a negative nexus opinion and explained that DMII was not causative for the development of hypertension except in the specific condition of kidney failure. The examiner indicated it would be speculative at best, given the Veteran's other risk factors, to apply a single causative factor (DMII) to the Veteran's development of hypertension. The examiner also indicated that a review of the medical record did not substantiate that the Veteran's hypertension was aggravated beyond its usual course secondary to DMII. The examiner noted that the natural course of hypertension was difficult to treat, without DMII complicating the clinical picture. The examiner indicated further that, in this case, it must again be referenced that there was no evidence of kidney failure that could be implicated as the cause of difficult to regulate hypertension. The examiner pointed out that the Veteran required very minimal titrations to his medication to obtain and maintain control of his hypertensive condition. The examiner concluded this was very consistent with the natural course of someone with a hypertensive condition and did not demonstrate a progression beyond the usual course. Likewise, the examiner opined that it could not be stated at a good medical probability of 50 percent or greater that the Veteran's hypertension was aggravated beyond its natural progression due to DMII. In spite of the medical opinions above, the Board finds that the current evidence is insufficient to adequately adjudicate the Veteran's claim. In that regard, while the May 2013 and November 2018 VA examiners indicate that the Veteran did not have diabetic nephropathy or kidney failure to establish causation between the Veteran's hypertension and DMII, this statement is conclusory. Further, it is not otherwise clear whether DMII could cause/contribute to hypertension without evidence of diabetic nephropathy/kidney failure, given the evidence of atherosclerotic calcification. As noted in the August 2006 VA examination report and the September 2009 VA treatment record, DMII aggravates hypertension due to earlier and extensive development of atherosclerosis due to hyperinsulinemia damaging the vascular endothelium and DMII accelerates arteriosclerosis increasing vascular resistance. Significantly, the Veteran's VA treatment records reflect a diagnosis for atherosclerotic calcification of the aorta in May 2012 and subsequently uncontrolled hypertension with increased oral medications in May 2013. See May 2012 and May 2013 VA Treatment records. As such, the Board finds that remand is warranted for a new VA medical opinion consistent with the directives herein. The matter is REMANDED for the following action: Forward the claims file to an appropriate examiner to obtain an addendum opinion as to the nature and etiology of the Veteran's hypertension. The claims file must be made available to, and be reviewed by, the examiner. The examiner should opine as to whether it is at least as likely as not (i.e., 50 percent probability or greater) that the Veteran's hypertension was caused, or aggravated, by his service-connected DMII. In answering this question, the examiner is directed to review the August 2006 VA examination and September 2009 VA treatment record indicating that the Veteran's hypertension was aggravated by his DMII based on the development of atherosclerosis and the May 2012 VA treatment record showing atherosclerotic calcification of the aorta. The examiner must also consider and discuss the May 2013 and November 2018 VA examination reports that indicate DMII was not a causative factor for the development of hypertension without evidence of diabetic nephropathy/kidney failure. The examiner must otherwise consider/discuss whether the Veteran's DMII caused/contributed to his hypertension without evidence of diabetic nephropathy/kidney failure. A rationale for all requested opinions shall be provided. The rationale must include a discussion of the underlying medical principles specific to the facts of this case and not simply reference generic medical literature. If the examiner cannot provide an opinion without resorting to mere speculation, he or she shall provide a complete explanation stating why this is so. In so doing, the examiner shall explain whether the inability to provide a more definitive opinion is the result of a need for additional information or that he or she has exhausted the limits of current medical knowledge in providing an answer to that particular question. A. ISHIZAWAR Veterans Law Judge Board of Veterans' Appeals Attorney for the Board Metzner, Paul 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.