Citation Nr: 21024854 Decision Date: 04/26/21 Archive Date: 04/26/21 DOCKET NO. 16-58 674 DATE: April 26, 2021 ORDER 1. Entitlement to a rating in excess of 10 percent for lumbar spine degenerative disc disease and degenerative joint disease prior to August 16, 2019 is denied. 2. Entitlement to a rating in excess of 20 percent for lumbar spine degenerative disc disease and degenerative joint disease from August 16, 2019 is denied. 3. Entitlement to service connection for obstructive sleep apnea (OSA) is granted. REMANDED Entitlement to service connection for upper gastrointestinal disability, claimed as acid reflux, is remanded. FINDINGS OF FACT 1. Prior to August 16, 2019, the preponderance of the evidence shows that the Veteran’s lumbar spine degenerative disc disease and degenerative joint disease was manifested by no worse than forward flexion of the thoracolumbar spine to 80 degrees and a combined range of motion (ROM) of 200 degrees. The Veteran’s condition did not result in muscle spasms or guarding severe enough to result in abnormal gait or abnormal spinal contour. The Veteran did not experience any form of ankylosis in the spine during this period. 2. From August 16, 2019, the preponderance of the evidence shows that the Veteran’s lumbar spine degenerative disc disease and degenerative joint disease has manifested by no worse than forward flexion of the thoracolumbar spine to 60 degrees and a combined ROM of 190 degrees. The Veteran did not experience any form of ankylosis in the spine during this period. 3. The weight of the most probative and competent evidence establishes that the Veteran’s OSA was proximately caused or aggravated by his service-connected acquired psychiatric disorder. CONCLUSIONS OF LAW 1. The criteria for a rating in excess of 10 percent for lumbar spine degenerative disc disease and degenerative joint disease prior to August 16, 2019 have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.10, 4.40, 4.45, 4.59, 4.71a, Diagnostic Code 5237, 5242. 2. The criteria for entitlement to a rating in excess of 20 percent for lumbar spine degenerative disc disease and degenerative joint disease from August 16, 2019 have not been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.10, 4.40, 4.45, 4.59, 4.71a, Diagnostic Code 5237, 5242. 3. The criteria for entitlement to service connection for OSA have been met. 38 U.S.C. §§ 1110, 1131, 5107; 38 C.F.R. §§ 3.102, 3.303, 3.310. REASONS AND BASES FOR FINDINGS AND CONCLUSIONS The Veteran served on active duty from November 1987 to January 1995, and from January 2004 to February 2005. These matters come before the Board of Veterans’ Appeals (Board) on appeal from an April 2015 rating decision issued by a Department of Veterans Affairs (VA) Regional Office (RO). These matters were previously before the Board in December 2018, where they were remanded to the Agency of Original Jurisdiction (AOJ) for additional development. The have now returned for appellate review. Increased Rating for Lumbar Spine Degenerative Disc Disease and Degenerative Joint Disease The Veteran seeks an increased evaluation for his service-connected lumbar spine degenerative disc disease and degenerative joint disease. See 03/31/2005 VA 21-4138, Statement in Support of Claim. Specifically, the Veteran contends that the symptoms of his lumbar spine degenerative disc disease and degenerative joint disease warrant a rating higher than 10 percent prior to August 16, 2019, and in excess of 20 percent, thereafter. Disability ratings are determined by evaluating the extent to which a Veteran’s service-connected disability adversely affects her ability to function under the ordinary conditions of daily life, including employment, by comparing her symptomatology with the criteria set forth in the Schedule for Rating Disabilities (Rating Schedule). See 38 U.S.C. § 1155; 38 C.F.R. § 4.1. Different ratings may be assigned for different periods of time for the same disorder if the facts show distinct time periods with different levels of disability. Fenderson v. West, 12 Vet. App. 119, 126 (1999); Hart v. Mansfield, 21 Vet. App. 505, 509-10 (2007). If two ratings are potentially applicable, the higher rating will be assigned if the disability more nearly approximates the criteria required for that rating; otherwise, the lower rating will be assigned. 38 C.F.R. § 4.7. Any reasonable doubt regarding the degree of disability will be resolved in favor of the Veteran. 38 C.F.R. § 4.3. In this case, staged ratings for the disability on appeal have already been assigned. From January 7, 1995 to August 15, 2019, (exclusive of the Veteran’s period of active duty service from January 4, 2004 to February 18, 2005), the Veteran was in receipt of a 10 percent evaluation for service-connected lumbar spine degenerative disc disease and degenerative joint disease. See 02/18/2005 DD 214. In an August 2020 rating decision, the Veteran was awarded an increased rating of 20 percent, effective August 16, 2019. Since this increase did not constitute a full grant of the benefit sought, the increased rating issue remains in appellate status. AB v. Brown, 6 Vet. App. 35, 39 (1993). When evaluating joint disabilities rated on the basis of limitation of motion, VA must consider granting a higher rating in cases in which functional loss due to pain, weakness, excess fatigability, or incoordination is demonstrated, and those factors are not contemplated in the relevant rating criteria. See 38 C.F.R. §§ 4.40, 4.45, 4.59; DeLuca v. Brown, 8 Vet. App. 202 (1995). The United States Court of Appeals for Veterans Claims (Court) later clarified that although pain may be a cause or manifestation of functional loss, limitation of motion due to pain is not necessarily rated at the same level as functional loss where motion is impeded. See Mitchell v. Shinseki, 25 Vet. App. 32 (2011). The Mitchell Court explained that pursuant to 38 C.F.R. §§ 4.40 and 4.45, the possible manifestations of functional loss include decreased or abnormal excursion, strength, speed, coordination, or endurance, as well as less or more movement than is normal, weakened movement, excess fatigability, and pain on movement (as well as swelling, deformity, and atrophy) that affects stability, standing, and weight-bearing. See 38 C.F.R. §§ 4.40, 4.45. Thus, functional loss caused by pain must be rated at the same level as if the functional loss were caused by any of the other factors cited above. In evaluating the severity of a joint disability, VA must determine the overall functional impairment due to these factors. The Veteran’s lumbar spine degenerative disc disease and degenerative joint disease has been rated under Diagnostic Code (DC) 5237 and 5242. Under 38 C.F.R. § 4.71a, DC 5237 and 5242 are both rated under the “General Rating Formula for Diseases and Injuries of the Spine.” The General Rating Formula for Diseases and Injuries of the Spine provides for a 10 percent rating where forward flexion of the thoracolumbar spine is greater than 60 degrees but not greater than 85 degrees; or, the combined range of motion of the thoracolumbar spine is greater than 120 degrees but not greater than 235 degrees; or, muscle spasm, guarding, or localized tenderness that does not result in abnormal gait or abnormal spinal contour; or, vertebral body fracture is present with loss of 50 percent or more of the height. A 20 percent rating is warranted where forward flexion of the thoracolumbar spine is greater than 30 degrees but not greater than 60 degrees; or, the combined range of motion of the thoracolumbar spine is not greater than 120 degrees; or, muscle spasm or guarding is severe enough to result in an abnormal gait or abnormal spinal contour such as scoliosis, reversed lordosis, or abnormal kyphosis. A 40 percent rating is warranted where forward flexion of the thoracolumbar spine is 30 degrees or less or there is favorable ankylosis of the entire thoracolumbar spine. A 50 percent rating is warranted where there is unfavorable ankylosis of the entire thoracolumbar spine. Finally, a 100 percent rating is warranted where there is unfavorable ankylosis of the entire spine. 38 C.F.R. § 4.71a. Any associated objective neurologic abnormalities, including but not limited to bowel or bladder impairment, are to be evaluated separately under the appropriate diagnostic codes. 38 C.F.R. § 4.71a, Note(1). Unfavorable ankylosis is defined by VA regulation as a condition in which the spine is fixed in flexion or extension, and the ankylosis results in one or more of the following: difficulty walking because of a limited line of vision; restricted opening of the mouth and chewing; breathing limited to diaphragmatic respiration; gastrointestinal symptoms due to pressure on the costal margin on the abdomen; dyspnea or dysphagia; atlantoaxial or cervical subluxation or dislocation; or neurological symptoms due to nerve root stretching. Id. at Note (5). Fixation in the neutral position of zero degrees always represents favorable ankylosis. Id. 1. Entitlement to a rating in excess of 10 percent for lumbar spine degenerative disc disease and degenerative joint disease prior to August 16, 2019 is denied. The Veteran seeks a rating in excess of 10 percent for lumbar spine degenerative disc disease and degenerative joint disease (hereinafter, lumbar spine disability), for the period prior to August 16, 2019. As background of the disability at issue, in an August 1995 rating decision, the Veteran was awarded service connection for low back pain rated as 10 percent disabling under DC 5237-5242, effective January 7, 1995. A May 2006 rating decision continued the 10 percent disability rating under DC 5237-5242, but recharacterized the Veteran’s low back pain as chronic lumbar syndrome with degenerative joint disease. Then, a May 2009 rating decision recharacterized the disability as lumbar spine degenerative disc disease and degenerative joint disease, and assigned a 10 percent rating under DC 5242-5243. The initial 10 percent evaluation for service-connected lumbar spine disability was in effect until August 16, 2019. Turning to the evidence, the Veteran was afforded a VA examination in March 2009 to evaluate the severity of his lumbar spine disability. See 03/04/2009 VA Examination. The Veteran reported recurrent his symptoms as daily back pain, stiffness, decreased ROM, weakness, and pain with prolonged standing and walking. The Veteran demonstrated forward flexion of the thoracolumbar spine to 80 degrees and a combined ROM of 232 degrees. The examiner acknowledged the Veteran’s reports of flare-ups once a month, but found that additional limitation due to flare-ups could not be determined without resorting to mere speculation. This examination is provided little evidentiary weight as it significantly predates the current period on appeal. The Veteran was next afforded a VA examination in August 2013, where the examiner noted a diagnosis of lumbar spine degenerative disc disease. See 08/02/2013 C&P Exam at 9. The Veteran reported progressively worsening symptoms, to include chronic back pain. The Veteran reported no flare ups. The Veteran demonstrated forward flexion of the thoracolumbar spine to 80 degrees, and a combined ROM for the thoracolumbar spine of 210 degrees. The examiner further reported: “ROM considered to be consistent with baseline for individual body habitus in this 50-year-old male with BMI 42.59 and increased abdominal girth.” Id. There was no muscle spasm or guarding in the lumbar spine. In April 2015, the Veteran was afforded another VA examination, where he reported progressively worsening daily pain in the lower back, requiring him to wear a soft brace when driving long distances. See 04/15/2015 C&P Exam at 3. The Veteran did not report flare ups. Upon examination, the Veteran demonstrated forward flexion to 80 degrees and a combined ROM for the thoracolumbar spine of 200 degrees. Like the August 2013 examiner, the April 2015 examiner indicated that the Veteran’s ROM was consistent with his baseline, considering his BMI 44.3 and increased abdominal girth. See id. at 4. There was no guarding or muscle spasm in the lumbar spine. The December 2018 Board decision stated that it was unclear whether the April 2015 VA examination was consistent with Correia v. McDonald, 28 Vet. App. 158 (2016). However, getting a new Correia-compliant examination, as was done in August 2019, does not resolve the issue for past examinations, and the Board finds that a retrospective opinion on the matter would be based on pure speculation. The April 2015 VA examiner clearly stated that the Veteran’s ROM was consistent with the baseline based on his body habitus, and thus, no further restriction was noted. Accordingly, the Board finds the April 2015 VA examination findings to be an accurate depiction of the Veteran’s typical range of motion of the back, regardless of the factors discussed in Correia, and it is the most compelling evidence available for consideration. The Board is further persuaded by the fact that the Veteran’s VA treatment records during the period prior to August 16, 2019 do not contain physical findings worse than those observed at the April 2015 VA examination. After careful review of the evidence of record, the Board finds that prior to August 16, 2019, the Veteran’s lumbar spine disability most approximated the level of disability contemplated by a 10 percent rating. Under DC 5242, a 10 percent rating is warranted where forward flexion of the thoracolumbar spine is greater than 60 degrees but not greater than 85 degrees; or, the combined range of motion of the thoracolumbar spine is greater than 120 degrees but not greater than 235 degrees; or, muscle spasm, guarding, or localized tenderness that does not result in abnormal gait or abnormal spinal contour; or, vertebral body fracture is present with loss of 50 percent or more of the height. 38 C.F.R. § 4.71a. Here, the evidence shows that prior to August 16, 2019, the Veteran’s lumbar spine disability was manifested by no worse than forward flexion to 80 degrees and a combined range of motion for the thoracolumbar spine of 200 degrees. See 08/02/2013 C&P Exam and 04/15/2015 C&P Exam. This level of disability is most closely approximated by a 10 percent rating, and a rating in excess of 10 percent is not warranted because there is no evidence to support a 20 percent rating, to include forward flexion of the thoracolumbar spine greater than 30 degrees but not greater than 60 degrees; a combined range of motion of the thoracolumbar spine not greater than 120 degrees; or, muscle spasm or guarding severe enough to result in an abnormal gait or abnormal spinal contour such as scoliosis, reversed lordosis, or abnormal kyphosis. Likewise, there is no evidence to support a 40 percent rating, which contemplates forward flexion of the thoracolumbar spine to 30 degrees or less. Finally, a 50 percent rating contemplates unfavorable ankylosis of the entire thoracolumbar spine, and a 100 percent rating is warranted where there is unfavorable ankylosis of the entire spine. 38 C.F.R. § 4.71a. For the period on appeal, there is no evidence of ankylosis at all, and a higher rating of 50 percent or 100 percent is therefore not warranted. Furthermore, there is no evidence of a diagnosis of intervertebral disc syndrome (IVDS), and a rating based on 38 C.F.R. § 4.71a (Formula for Rating IVDS) therefore is not applicable. For the above reasons, the Board finds that the Veteran’s lumbar spine disability is more nearly approximated by the 10 percent level for the period prior to August 16, 2019. The weight of the competent and probative evidence preponderates against the claim for an increased rating, and there is no doubt to resolve. 38 C.F.R. § 4.3. Accordingly, the appeal for a rating in excess of 10 percent prior to August 16, 2019 is denied. In reaching this conclusion, the Board considered functional loss due to pain and weakness that causes additional disability beyond that which is reflected on range of motion measurements. 38 C.F.R. § 4.40; DeLuca, supra. The Board has considered the effects of weakened movement, excess fatigability, and incoordination. 38 C.F.R. § 4.45. Although the Board accepts the Veteran’s assertions that his lumbar spine disability causes him to experience pain, the Board has taken this into account in its above discussion of range of motion. The rating schedule does not require a separate rating for pain itself. Spurgeon v. Brown, 10 Vet. App. 194 (1997). Furthermore, even when the Veteran’s complaints of pain are considered, the Board concludes that the overall manifestations of his lumbar spine disability generally do not demonstrate a degree of functional loss so as to warrant higher ratings for the period on appeal. Moreover, even if flexion was limited by pain, pain alone is not sufficient to warrant a higher rating, as pain may cause a functional loss, but pain itself does not constitute functional loss. Mitchell, 25 Vet. App. at 36-38. Rather, pain must affect some aspect of “the normal working movements of the body” such as “excursion, strength, speed, coordination, and endurance,” in order to constitute functional loss. Id. at 43; see 38 C.F.R. § 4.40. In this case, it does not. Additionally, for the period prior to August 16, 2019, the Board finds no convincing evidence that the Veteran’s service-connected lumbar disability manifested in any neurological abnormalities. Muscle strength, reflex, and sensation testing were normal at the August 2013 and April 2015 VA examinations and radiculopathy or other abnormal neurological findings were not identified. The Veteran’s lay report of an episodic “numbness-like” symptom at the April 2015 VA examination was not corroborated on physical examination, and the Board affords the objective evaluation more weight than uncorroborated lay reports. Moreover, VA treatment records during this time period did not document abnormal neurological findings. 2. Entitlement to a rating in excess of 20 percent for lumbar spine degenerative disc disease and degenerative joint disease from August 16, 2019 is denied. As noted above, an August 2020 rating decision awarded the Veteran an increased 20 percent rating for lumbar spine disability, effective August 16, 2019. Nonetheless, the grant of an increased rating during the course of an appeal does not affect the pendency of that appeal. AB, supra. As the Veteran is presumed to be seeking the maximum allowable benefit and the maximum benefit has not yet been awarded, the claim is still in controversy and remains on appeal. Id. at 39. The RO correctly chose the August 16, 2019 date of the examination for the increased rating, as this was the first date in the record that it was factually ascertainable that the Veteran satisfied the criteria for a higher 20 percent rating. See Swain v. McDonald, 27Vet. App.219 (2015). Turning to the evidence, the Veteran was afforded a VA examination in August 2019. See 08/21/2019 C&P Exam. The Veteran did not report flare ups. Upon examination, the Veteran demonstrated forward flexion of the thoracolumbar spine to 60 degrees and a combined ROM of 190 degrees. See id. at 3. The Veteran reported constant aching low back pain with increased pain with prolonged sitting or standing, and using a back brace and cane occasionally. Id. at 2. He also reported experiencing limitations in his ability to bend, lift, and stand or sit for prolonged periods of time, but no flare ups. The examiner reported that pain resulting in functional loss was noted during the examination, as well as evidence of pain with weight-bearing. See id. at 4. However, the examiner also reported that there was no evidence that pain, weakness, fatigability, or incoordination significantly limits functional ability after repeated use over time. See id. at 5. Passive range of motion testing was not performed as it was determined to be not feasible to do in a safe and reasonable manner. Testing during nonweight-bearing was deemed to be inapplicable, as there was no pain during nonweight-bearing and at rest. The Veteran’s VA treatment records since August 16, 2019 do not contain physical findings worse than those observed at the August 2019 VA examination. After a careful review of the evidence of record, the Board finds that from August 16, 2019, the Veteran’s lumbar spine disability most closely approximates the level of disability contemplated by a 20 percent rating. Under DC 5242, a 20 percent rating is warranted where forward flexion of the thoracolumbar spine is greater than 30 degrees but not greater than 60 degrees and muscle spasm or guarding is severe enough to result in an abnormal spinal contour. 38 C.F.R. § 4.71a. Here, the evidence shows that from August 16, 2019, the Veteran’s lumbar spine disability manifests by no worse than forward flexion to 60 degrees and a combined ROM of 190 degrees. See 08/21/2019 C&P Exam. The Board observes that there is no other evidence of record regarding the severity of the Veteran’s lumbar spine disability for the period beginning August 16, 2019. A rating in excess of 20 percent is not warranted because there is no evidence of forward flexion of the thoracolumbar spine to 30 degrees or less for the period beginning August 16, 2019, as required for a 40 percent rating. As noted above, a 50 percent rating contemplates unfavorable ankylosis of the entire thoracolumbar spine, and a 100 percent rating is warranted where there is unfavorable ankylosis of the entire spine. 38 C.F.R. § 4.71a. For the period on appeal, there is no evidence of ankylosis, so a higher rating of 50 percent or 100 percent is therefore not appropriate. Further, there is no evidence of a diagnosis of IVDS, therefore 38 C.F.R. § 4.71a does not apply. For the above reasons, the Board finds that from August 16, 2019, the Veteran’s lumbar spine degenerative disc disease and degenerative joint disease is more nearly approximated by the 20 percent level. The weight of the competent and probative evidence preponderates against the claim for an increased rating, and there is no doubt to resolve. 38 C.F.R. § 4.3. Accordingly, the appeal for a rating in excess of 20 percent from August 16, 2019 is denied. In the August 2020 rating decision, the Veteran was awarded a 10 percent rating for left lower extremity radiculopathy, effective August 16, 2019, based on the results of the August 2019 VA examination. There is no allegation from the Veteran or his attorney that he has experienced worse than mild incomplete paralysis in the left leg, or any other abnormal neurological findings, to include in the right lower extremity. The Veteran’s contemporaneous VA treatment records do not document worse than mild radiculopathy, and the Board applies the common meaning of the word mild, which is generally defined as “not severe.” Merriam-Webster’s Collegiate Dictionary, 787 (11th ed. 2003). Accordingly, further ratings for neurological abnormalities are not warranted for the period since August 16, 2019. SERVICE CONNECTION 1. Entitlement to service connection for OSA is granted. The Veteran seeks service connection for OSA, claimed as sleep condition, to include on the basis of aggravation by his service-connected adjustment disorder with mixed anxiety and depressed mood. Service connection may be granted for disability resulting from disease or injury incurred in or aggravated during service. 38 U.S.C. § 1110; 38 C.F.R. § 3.303. That determination requires a finding of current disability that is related to an injury or disease in service. Watson v. Brown, 4 Vet. App. 309 (1993); Rabideau v. Derwinski, 2 Vet. App. 141 (1992). Service connection may be granted for a disability diagnosed after discharge, when all the evidence, including that pertinent to service, establishes that the disability is due to disease or injury that was incurred or aggravated in service. 38 C.F.R. § 3.303(d). In order to establish entitlement to secondary service connection, there must be: (1) evidence of a current disability; (2) evidence of a service-connected disability; (3) medical evidence establishing a nexus between the service-connected disability and the current disability. See Wallin v. West, 11 Vet. App. 509, 512 (1998). Additionally, regulations provide that 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. Further, a disability which is aggravated by a service-connected disorder may be service connected to the degree that the aggravation is shown. Allen v. Brown, 7 Vet. App. 439, 449 (1995); 38 C.F.R. § 3.310. The standard of proof to be applied in decisions on claims for Veterans’ benefits is set forth at 38 U.S.C. § 5107. A claimant is entitled to the benefit of the doubt when there is an approximate balance of positive and negative evidence. See 38 C.F.R. § 3.102. When a claimant seeks benefits and the evidence is in relative equipoise, the claimant prevails. See Gilbert v. Derwinski, 1 Vet. App. 49 (1990). The preponderance of the evidence must be against the claim for benefits to be denied. See Alemany v. Brown, 9 Vet. App. 518 (1996). * * * Turning to the evidence, the Veteran was diagnosed with OSA and prescribed CPAP therapy following a sleep study in February 2015. See 11/29/2016 private disability benefits questionnaire (DBQ); see also February 2015 polysomnography report. The Board also notes that the Veteran has been service-connected for adjustment disorder with mixed anxiety and depressed mood since October 2014, currently rated as 30 percent disabling. In November 2016, the Veteran submitted a private medical opinion by Dr. M.B., M.D. See 11/29/2016 private DBQ. After reviewing the claims file and interviewing the Veteran, Dr. M.B. opined that it is at least as likely as not that the Veteran’s depressive disorder and anxiety aided in the development of and permanently aggravated his OSA. Dr. M.B.’s rationale was that research shows that psychiatric disorders are commonly associated with OSA, and that individuals with depression have a higher prevalence of sleep apnea. See 01/04/2021 Correspondence at 3. The Veteran was first afforded a VA examination in July 2020. 07/30/2020 C&P Exam. The July 2020 examiner opined that it was less likely than not that the Veteran’s service-connected adjustment disorder with mixed anxiety and depressed mood led to his OSA. See id. at 3. As rationale, the examiner stated that based on medical literature, OSA typically causes symptoms of depression, but not vice versa. See id. After the July 2020 VA examination, the AOJ requested an addendum medical opinion that considered the Veteran’s Reserve service treatment records (STRs) which show a January 2005 complaint of still feeling tired after sleeping. See 08/20/2020 Exam Request; see also 12/04/2019 STR – Reserve STR at 22. In an August 2020 addendum opinion, the examiner opined that the Veteran’s January 2005 report of feeling tired after sleeping was likely related to post-traumatic stress disorder (PTSD), not OSA. See 08/31/2020 C&P Exam. The examiner further opined that because PTSD does not cause OSA, the Veteran’s OSA was less likely than not related to military service. See id. The Board has reviewed the three medical opinions above and finds that the evidence weighs in favor of concluding that the Veteran’s OSA is proximately caused or aggravated by his service-connected adjustment disorder with mixed anxiety and depressed mood. On balance, the Board finds Dr. M.B.’s November 2016 opinion to be more probative and persuasive, as it shows greater consideration of relevant lay and medical evidence, includes references to relevant medical literature, and provides a thorough rationale. See Guerrieri v. Brown, 4 Vet. App. 467, 470-71(1993) (holding that the credibility and weight of opinions are within the province of the adjudicator). Notably, Dr. M.B.’s opinion contains a detailed discussion of the co-morbidity of psychiatric disorders and OSA. As Dr. M.B.’s opinion shows adequate consideration of the relevant evidence and is supported by a medical rationale, the Board finds it is worthy of probative weight. Conversely, the VA examiner’s rationale for the July 2020 medical opinion was medical literature supports a finding that OSA typically causes symptoms of depression, but depression does not cause symptoms of OSA. However, the Board finds that the July 2020 opinion is inadequate, as it lacks a comprehensive rationale and is therefore entitled to limited probative value. See also Bailey v. O’Rourke, 30 Vet. App. 54, 60 (2018) (holding that medical opinions that rely on the absence of general medical literature supporting a nexus without discussing the specific facts of a case are inadequate as a matter of law). Further, both the July and August 2020 medical opinions fail to show adequate consideration of the relevant evidence. Significantly, neither opinion shows consideration of Dr. M.B.’s November 2016 medical opinion. VA is required to give due consideration to all pertinent medical and lay evidence in evaluating a claim for disability benefits. Davidson v. Shinseki, 581 F.3d 1313, 1316 (Fed Cir. 2009). Moreover, the August 2020 addendum opinion is inadequate because it only pertains to a nexus between OSA and PTSD, and fails to address the question of nexus with regard to the Veteran’s OSA and service-connected adjustment disorder with mixed anxiety and depressed mood. Thus, as the July and August 2020 medical opinions lack an adequate rationale and fail to show consideration of all the relevant evidence, the Board finds them to be entitled to very little probative weight. Based on the above, and resolving doubt in the favor of the Veteran, the Board finds that the most probative evidence establishes that the Veteran’s OSA was proximately caused or aggravated by service-connected adjustment disorder with mixed anxiety and depressed mood. 38 U.S.C. § 5107(b); 38 C.F.R. § 3.310. As such, entitlement to service connection for OSA as secondary to service-connected adjustment disorder with mixed anxiety and depressed mood is warranted. REASONS FOR REMAND Entitlement to service connection for upper gastrointestinal disability, claimed as acid reflux, is remanded. The Veteran seeks service connection for an upper gastrointestinal disability, claimed as acid reflux. This claim was remanded by the Board in December 2018 as a petition to reopen a previously disallowed claim, as this matter was last adjudicated in an unappealed October 2013 rating decision. Since that time, additional relevant service treatment records have been obtained that were in existence but not available at the time of the prior disallowance. See DPRIS records received July 2019; see STRs received December 2019; see also 38 C.F.R. § 3.156(c). Accordingly, new and material evidence is not necessary to reopen the previously disallowed claim, and it will be reconsidered on a de novo basis pursuant to 38 C.F.R. § 3.156(c). A review of the record shows that the throughout the appeal period, the Veteran has been diagnosed with several upper gastrointestinal disabilities, to include gastroesophageal reflux disease (GERD), esophageal reflux, hiatal hernia, dysphagia, and achalasia. See 05/09/2006 VA Examination; see also 09/07/2013 CAPRI. Accordingly, the Board has recharacterized the disability on appeal as upper gastrointestinal disability in accordance with Clemons v. Shinseki, 23 Vet. App. 1 (2009). Although the Board regrets the additional delay, a remand is necessary to ensure that due process is followed and there is a complete record upon which to decide the Veteran’s claim, so he is afforded every possible consideration. See 38 U.S.C. § 5103A; 38 C.F.R. § 3.159. VA’s duty to assist includes a duty to provide a medical examination or obtain a medical opinion where it is deemed necessary to decide on the claim. 38 U.S.C. § 5103A(d); 38 C.F.R. § 3.159(c)(4); McLendon v. Nicholson, 20 Vet. App. 79, 81-83 (2006). The threshold for finding that a VA examination and medical opinion are required due to a link between current disability and service is low. McLendon, 20 Vet. App. at 83. For the reasons set out below, the Board finds that a VA examination is necessary to determine the nature and etiology of the Veteran’s upper gastrointestinal disability. Pursuant to the December 2018 Board remand, the AOJ obtained and associated with the claims file service treatment records (STRs) from the Veteran’s second period of active duty service, from January 2004 to February 2005. See 12/04/2019 STR – Reserve STR. A review of the STRs from the Veteran’s second period of service reveals that the Veteran listed acid reflux as a current medical problem on his May 2005 Initial Medical Review – Annual Medical Certificate, and reported undergoing surgery on his esophagus in October or November 2002. See id. at 15 and 18. Similarly, STRs show that in October 2005, he sought treatment for acid reflux and reported undergoing a Nissen fundoplication for GERD two years prior, and received in a diagnosis of esophageal reflux. See id. at 20. These records from 2005 are in close proximity to the Veteran’s second period of active duty service. Finally, the Board observes that STRs from the Veteran’s first period of active duty service reveal that in April 1989, the Veteran complained of an upset stomach. See 01/27/1995 STR at 120. The Veteran has not yet been afforded a VA examination to determine the nature and etiology of his upper gastrointestinal disability and whether it is related to his active military service. Accordingly, on remand, the Veteran should be afforded a VA examination and medical opinion. See 38 U.S.C. § 5103A(d); McLendon, 20 Vet. App. at 83. The matter is REMANDED for the following action: 1. Schedule a VA examination (or telehealth interview, review of the record etc. if an in-person examination is not feasible due to the current pandemic) with an appropriate VA clinician to determine the nature and etiology of any current upper gastrointestinal disability. Based on a review of the evidence, to include a copy of this Remand, the clinician is asked to provide a response to the following: (a.) Is it at least as likely as not (50 percent probability or greater) that any current upper gastrointestinal disability is etiologically related to the Veteran’s active military service? When formulating the requested opinion, please specifically note and consider the following evidence: service records showing reports of an upper gastrointestinal disability in May and October 2005 (slightly after the Veteran’s second period of active service), and reports of an upset stomach in April 1989. 12/04/2019 STR – Reserve STR at 15, 18, 20, 01/27/1995 STR at 120. A comprehensive rationale for all opinions is to be provided. All pertinent evidence, including both lay and medical, should be considered. If an opinion cannot be given without resorting to speculation, the examiner should explain why and 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), the record (additional facts are required), or the examiner (does not have the knowledge or training). M. GALANTE Acting Veterans Law Judge Board of Veterans’ Appeals Attorney for the Board T. Tremont 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.