Citation Nr: 21063354 Decision Date: 10/14/21 Archive Date: 10/14/21 DOCKET NO. 17-28 387 DATE: October 14, 2021 REMANDED Entitlement to service connection for sleep apnea, to include as secondary to depression and/or a back disability, is remanded. REASONS FOR REMAND The Veteran served on active duty in the United States Marine Corps from July 1991 to July 1995. This matter comes before the Board of Veterans' Appeals (Board) on appeal from a May 2016 rating decision by an Agency of Original Jurisdiction of the Department of Veterans Affairs. In May 2019, the Veteran testified at a video conference hearing before the undersigned. In October 2019 and March 2021, the Board remanded this matter for additional development. The Board regrets the delay, but remand is again necessary for additional development. In this regard, the April 2021 examiner opined that the Veteran's sleep apnea was less likely than not due to service and noted that obesity is the best documented risk factor for sleep apnea. While obesity is not a disability for VA compensation purposes, obesity may serve as an intermediate step between a service-connected disability and a nonservice-connected disability that is proximately due to or aggravated by that service-connected disability. See VAOGCPREC 01-2017 (Jan. 6, 2017). Moreover, secondary service connection may be granted where a service-connected disability aggravates obesity and obesity aggravates a non-service-connected disability. See Walsh v. Wilkie, 32 Vet. App. 300 (2020). The Veteran has a current diagnosis of sleep apnea, and he is presently in receipt of service connection for, among other things, a back disability and depressive disorder. Moreover, the Board observes that the April 2021 VA examiner found that the primary risk factor for sleep apnea is obesity and that the Veteran is obese (BMI 36.5 in 2016). The Board finds that an addendum opinion should be obtained as to whether the Veteran's obesity was proximately caused by his service-connected disabilities. In this regard, the April 2021 examiner's opinion establishes that the Veteran's obesity was at least a "substantial factor" in causing sleep apnea. Updated VA treatment records should also be secured. The matters are REMANDED for the following action: 1. Obtain updated VA treatment records. 2. After obtaining any outstanding records to the extent possible, secure an addendum opinion addressing the etiology of the Veteran's sleep apnea. No additional examination is needed unless the examiner determines otherwise. The claims file should be made available to and should be reviewed by the examiner. The examiner should address the following questions: (a.) Is it at least as likely as not (50 percent or greater probability) that the Veteran's service-connected disabilities caused him to become obese? (b.) Is it at least as likely as not (50 percent or greater probability) that the Veteran's obesity has been aggravated (worsened beyond natural progression) by his service-connected disabilities? (c.) Is it at least as likely as not that his sleep apnea would not have occurred but for obesity caused by the service-connected (or service-related) disability? Please answer each sub-part of this question separately. A complete rationale must be provided for all opinions rendered. If it is not possible to provide any of the requested opinion without resorting to speculation, please state whether the need to speculate is due to a deficiency in the state of general medical knowledge (no one could respond given medical science and the known facts); in the record (additional facts required); or in your own knowledge or training. S. BUSH Veterans Law Judge Board of Veterans' Appeals Attorney for the Board D. Saumur, 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.