SLEEP APNEA SYNDROMES (OBSTRUCTIVE CENTRAL MIXED)

Summary

The veteran, who served from June 1998 to June 2003, appeals the denial of service connection for obstructive sleep apnea (OSA) as secondary to his service-connected bilateral knee disability. The veteran contended that his weight gain, caused by knee pain that limited his ability to exercise, led to OSA. He cited his knee disability, subsequent sleep disturbances, and weight gain as evidence. The Board reviewed the veteran's service treatment records (STRs), enlistment and separation examinations, and post-service medical treatment notes. The STRs showed the veteran was underweight at enlistment and gained weight during service, with his weight fluctuating between 170-182 pounds by the end of service. Post-service, OSA was diagnosed in June 2015 when the veteran weighed 224 pounds. The Board found the veteran's service-connected knee disability did not cause his obesity. Evidence indicated the veteran remained active post-service, playing competitive softball and golf, and did not report knee pain interfering with exercise. Weight gain was primarily attributed to dietary choices and demanding work schedules. While private examiners opined that obesity was more likely than not due to knee disability, the Board found these opinions lacked probative value due to reliance on unsubstantiated facts and failure to address contradictory evidence. The Board noted the veteran's knee complaints to examiners were inconsistent with his reported activity levels and lack of treatment for knee pain post-service. A VA examiner opined that obesity was less likely than not the result of the knee disability, citing diet and lifestyle factors. The Board found this VA opinion probative and consistent with the clinical evidence. The Board denied service connection for OSA as secondary to the knee disability, finding the causal link unproven.

Rationale

Probative evidence shows weight gain not due to bilateral knee disability.; Veteran remained active post-service and did not report knee pain interfering with exercise.; Private opinions lacked probative value due to reliance on erroneous facts and failure to address contradictory evidence.

Full Decision Text

Citation Nr: A25008143
Decision Date: 01/29/25	Archive Date: 01/29/25

DOCKET NO. 230613-354374
DATE: January 29, 2025

ORDER

Service connection for obstructive sleep apnea (OSA) as secondary to a service-connected bilateral knee disability is denied.

VETERAN'S CONTENTIONS

The Veteran contends that he developed OSA as a result of weight gain secondary to an impaired ability to exercise due to his service-connected bilateral knee disability.  Through medical opinions and lay statements submitted in support of his claim, the Veteran asserts that his OSA was proximately due to obesity, and that his obesity was caused by chronic knee pain post service that caused sleep disturbances and impaired his ability to exercise.  In support of his assertion, he also points out that impaired sleep can result in an increased appetite and that his weight gain occurred chronologically after the onset of his knee disabilities near the end of active service.  Accordingly, he argues that service connection for OSA is warranted.

FINDING OF FACT

The most probative evidence supports that the Veteran's weight gain was not due to a bilateral knee disability, and therefore that OSA was not incurred as a result of a service-connected knee disability.

CONCLUSION OF LAW

The criteria for service connection for OSA as secondary to a service-connected knee disability are not met.? 38 U.S.C. §§ 1110, 5107;?38 C.F.R. §§ 3.102, 3.303, 3.310.

REASONS AND BASES FOR FINDING AND CONCLUSION

The Veteran served on active duty from June 1998 to June 2003.  This matter is before the Board following his appeal of a May 2023 rating decision issued following receipt of a supplemental claim in January 2023.  However, the date of claim here is January 27, 2022, as the Veteran has continuously pursued that claim.

On his June 2023 VA Form 10182, the Veteran selected the direct review docket.  As such, the Board may only consider evidence of record at the time of the May 10, 2023, rating decision on appeal.  If the Veteran wishes to have VA consider any evidence that was added to the record after May 10, 2023, a supplemental claim should be submitted identifying such evidence.  See 38 C.F.R. § 3.2501.

Service Connection for Obstructive Sleep Apnea

Service connection may be granted where a disability is proximately due to or aggravated by an already service-connected disability.  38 C.F.R. § 3.310.  To establish secondary service connection for a disability there must be (1) a current disability (for which secondary service connection is sought); (2) an existing service-connected disability, and (3) evidence that the current disability for which service connection is sought was either (a) caused or (b) aggravated by the service-connected disability.  38 C.F.R. § 3.310.  See Allen v. Brown, 7 Vet. App. 439 (1995) (en banc). 

As is relevant here, the United States Court of Appeals for Veterans Claims (CAVC) has held that obesity can serve as an "intermediate step" in a causal chain for service connection.  See Walsh v. Wilkie, 32 Vet. App. 300 (2020).  According to CAVC, service connection may be granted on a secondary basis where the claimed disability would not have occurred but for obesity caused or aggravated by a service-connected disability.  Id.; see also?VAOPGCPREC 1-2017?(January 6, 2017).  In order to meet this criterion, the Veteran must demonstrate that a previously service-connected disability caused the Veteran to become obese; that obesity was a substantial factor in causing secondary disability; and the secondary disability would not have occurred but for the obesity. 

Here, the Board finds that service connection is not warranted because the probative evidence does not show that the Veteran's service-connected bilateral knee disability caused the Veteran to become obese.  On the contrary, the probative evidence shows that the Veteran gained weight during service prior to any knee disability and his weight gain was, at least in part, subsequently attributed to a growth spurt in service.  The evidence further shows that the Veteran continued to be active after service without complaints of interference by his service-connected bilateral knee disability, that periods of inactivity were attributed to other causes including demanding or difficult school and/or work schedules, and that his post-service weight gain was attributed to other causes such as quality of his diet. 

Turning to the medical evidence, the Veteran's service treatment records (STRs) are silent for diagnosis
ative evidence does not show that the Veteran's service-connected bilateral knee disability caused the Veteran to become obese.  On the contrary, the probative evidence shows that the Veteran gained weight during service prior to any knee disability and his weight gain was, at least in part, subsequently attributed to a growth spurt in service.  The evidence further shows that the Veteran continued to be active after service without complaints of interference by his service-connected bilateral knee disability, that periods of inactivity were attributed to other causes including demanding or difficult school and/or work schedules, and that his post-service weight gain was attributed to other causes such as quality of his diet. 

Turning to the medical evidence, the Veteran's service treatment records (STRs) are silent for diagnosis or treatment for OSA.  During his enlistment examination in September 1997, the Veteran was noted to weigh 137 pounds and have a slender build.  Throughout his service, he grew some in height and steadily gained weight; towards the end of service his weight fluctuated between 170 and 182 pounds.  See January 2001 to June 2003 STRs.  During a March 2003 (presumed) separation examination, the Veteran was noted to weigh 180 pounds and offered no knee complaints in reporting his medical history.  However, he was found on examination to have a left tibial tuberosity that was tender to pressure and hurt with deep knee bend.  Nevertheless, his gait was "good," he was able to fully flex and extend the knee, and x-ray of the left knee was normal.  There were no right knee findings. 

In April 2003, the Veteran was again noted to weigh 180 pounds.  At that time, the service provider noted that on separation physical examination of the Veteran, a bilateral patellar bump was found, left greater than right.  However, the Veteran reported that he played softball and ran without any pain.  Objectively, there was tenderness to the "tibial tube bump," left greater than right, but the Veteran was observed to ambulate without difficulty and there was no pain on range of motion testing.  Of note, the Veteran was ordered not to run for two weeks.  Then, during treatment in June 2003, approximately two weeks prior to separation on June 28, 2003, the Veteran was noted to weigh 174 pounds.  Thus, from the time of onset of the bilateral patellar knee bumps (ultimately assessed as exostosis of the bilateral tibial tuberosity) and separation, the Veteran lost six pounds. 

Post-service evidence shows that OSA was diagnosed in June 2015 following a sleep study that was performed based on the Veteran's April 2015 report that he snored and that apneic events were witnessed during a recent ski trip with friends.  See June 2015 VA Treatment Notes; February 2022 VA Examination Report.  At that time, the Veteran weighed 224 pounds.  Of note, when the Veteran reported the witnessed apneic episodes in April 2015, he also reported that his weight was up 40 pounds in the last 10 years.  Importantly, at that time, he made no mention of his knee disability or any inability to exercise because of knee or joint pain.

In fact, the clinical evidence shows that, after approximately the first year and a half following separation from service, there were no complaints of, or treatment related to, any service-connected knee disability prior to June 2015, to specifically include any reports of weight gain or an inability to exercise or workout due to any knee problems.  Although a history of knee problems or Osgood-Schlatter's disease was noted from time to time, including in August 2007, the Veteran generally did not seek treatment for or complain of active knee pain after 2004.  While the Board acknowledges that the Veteran sought treatment for right knee pain following a softball game in October 2008, both he and the treating provider distinguished the knee pain from the Veteran's service-connected knee disability.  In that regard, upon seeking treatment, the Veteran stated that "[t]his is new pain" and "a different pain."  The VA provider also noted that "this is clearly a separate pain," as the Veteran reported the current pain behind the knee as opposed to the front of the knee, as with Osgood-Schlatter's disease or the service-connected exostosis if the tibial tuberosity.  See October 2008 VA Treatment Notes.  

Regardless, despite his reported knee pain, including soon after separation and in October 2008, the Veteran was still clearly able to engage in exercise and physical activity, and he did not report at any time that knee pain prevented him from or seriously inhibited exercise.  Indeed, following service, the record showed that the
 stated that "[t]his is new pain" and "a different pain."  The VA provider also noted that "this is clearly a separate pain," as the Veteran reported the current pain behind the knee as opposed to the front of the knee, as with Osgood-Schlatter's disease or the service-connected exostosis if the tibial tuberosity.  See October 2008 VA Treatment Notes.  

Regardless, despite his reported knee pain, including soon after separation and in October 2008, the Veteran was still clearly able to engage in exercise and physical activity, and he did not report at any time that knee pain prevented him from or seriously inhibited exercise.  Indeed, following service, the record showed that the Veteran was observed on at least one occasion to appear healthy-looking and muscular, and was noted to be actively involved in softball leagues at a "very competitive level," to play golf or ski, to walk, go the gym, and/or to use a treadmill regularly.  See June 2004, August 2007, September 2007, October 2008, July 2013, December 2013, March 2014, July 2014, November 2014, January 2015, August 2015, September 2015, February 2016, July 2018, December 2018, February 2019, June 2019, and February 2023 VA Treatment Notes.  At none of those times did the Veteran report difficulty with or an inability to perform those activities due to a knee or joint disability.  He was also able to complete a treadmill exercise stress test in July 2018 without any knee complaints or interference.  Although in June 2019, the Veteran reported feeling like he had to catch his breath while golfing, he offered no knee impairment.  Furthermore, the clinical evidence shows that when limited physical activity was discussed, it was in the context of the Veteran's demanding or difficult school or work schedule, difficulty structuring his time, or difficulty maintaining motivation to exercise.  See May 2013, September 2013 and December 2018 VA Treatment Notes.

Similarly, the clinical evidence shows that the Veteran's weight gain was primarily discussed in the context of his work schedule and dietary choices with some periodic discussion of the need to increase exercise.  Again, at no time during those weight discussions was an inability to or difficulty with exercise due to knee pain or joint problems mentioned.  For example, in May 2013, the Veteran discussed his challenging shift work that affected his energy, and the Veteran was encouraged to reestablish an exercise program during his days off; the Veteran did not express concern about his ability to perform exercise due to his knee disability.  In April 2014, it was noted that the Veteran had gradually gained weight (35 pounds or so) within the last 5 years.  At that time, the Veteran reported that having a difficult work schedule made it difficult to eat healthier, as he would often order in for lunch.  He also stated that he did not like to cook and would, therefore, often eat processed or easy-to-prepare foods at home.  During a July 2018 wellness visit, it was noted that the Veteran was obese and the provider "discussed diet which is his main issue."  The Veteran again reported that he did not like to cook and frequently ate out.  In December of 2018, the Veteran reported limited physical activity after noting he switched to a new job that required him to work 6-7 days per week during the busy season.  More recently, in September 2019, the Veteran reported walking, playing golf, and "trying to be active" without mention of joint or knee pain or interference, but it was noted that he had "not given up pop altogether and is still not eating quite as healthy as he might."  In February 2022, he stated that 95 percent of his diet came from fast food and soda, though he was walking 1.5 miles per day and planned to start strength training.

The Board is cognizant that the Veteran did offer knee complaints during VA examinations.  For example, during a July 2004 VA examination, the Veteran reported constant pain in the area of the bumps and difficulty kneeling, running, and jumping because of knee pain.  He similarly reported constant pain in his knees that worsened with running during a September 2005 VA examination.  At that time, he stated that he had "not been able to run."  However, his reports during VA examinations are somewhat inconsistent with the in- and post-service clinical evidence.  In that regard, in April 2003, he stated that he ran without any difficulty, and during March 2004 VA treatment he described the pain as intermittent and as occurring after an activity, in contrast to his reports
 knee complaints during VA examinations.  For example, during a July 2004 VA examination, the Veteran reported constant pain in the area of the bumps and difficulty kneeling, running, and jumping because of knee pain.  He similarly reported constant pain in his knees that worsened with running during a September 2005 VA examination.  At that time, he stated that he had "not been able to run."  However, his reports during VA examinations are somewhat inconsistent with the in- and post-service clinical evidence.  In that regard, in April 2003, he stated that he ran without any difficulty, and during March 2004 VA treatment he described the pain as intermittent and as occurring after an activity, in contrast to his reports of constant pain to the VA examiners.  He also reported an ankle injury that occurred playing softball in June 2004, and, in August 2007, he stated that he felt well physically, suggesting that he was still physically capable despite his reports of knee pain.

Even further, except for on the day of his VA knee examination, the Veteran consistently reported his pain level as a "0" on a 0 to 10 scale or attributed the pain to a specific problem unrelated to the knee, such as his ankle, chest, eye, abdomen, head, or back.  See, e.g., August 2007, September 2007, June 2008, August 2008, October 2008, January 2009, October 2009, May 2013, April 2014, October 2014, April 2015, June 2018, and June 2019 VA Treatments Notes.  In fact, in May 2013, the Veteran specifically reported that his service-connected knee disability was not an active issue.  The Board is cognizant of the Veteran's reports to examiners that he took over-the-counter medications for his knee pain and that early post service VA treatment notes reference ibuprofen for knee pain.  However, in August 2007 he denied taking aspirin, ibuprofen, or other medication regularly, and in September 2007 he stated that he rarely used medication.  Interestingly, however, though he rarely used medication, he did affirmatively report in September 2007 that he took Tylenol or Advil at times for headaches; he did not mention use of those medications for knee pain.  Those reports weigh against a finding of that the Veteran had chronic knee pain that was so severe that it would interfere with exercise or sleep.

The Board is cognizant that the Veteran has submitted private opinions in support of his assertion that his OSA is the result of obesity that was caused by an inability to exercise due to his service-connected knee disability.  As is particularly relevant here, private examiners opined in January 2022 and January 2023 that the Veteran's obesity was more likely than not due to or caused by his service-connected knee disabilities.  However, the Board finds that those opinions are devoid of any probative value as they were predicated on erroneous or unsubstantiated facts.

In that regard, in providing positive nexus opinions, the private examiners relied on findings that the Veteran experienced chronic knee pain post service with resulting sleep disturbances caused by that pain.  Of note, the January 2022 examiner stated that the Veteran "was awarded service connection with consideration of the following symptomatology: pain, painful motion, and associated sleep disturbances with insomnia and frequent awakenings."  In the January 2023 opinion, that examiner based her opinion on the Veteran's knee disability "with subsequent sleep disturbance and weight gain/obesity" and also noted the Veteran to be service connected for knee disabilities "with associated symptoms to include pain, painful range of motion, and associated sleep disturbance related to the pain."  The examiners cumulatively went on to discuss how pain causes decreased physical activity, a more sedentary lifestyle, impaired sleep that results in increased hunger and appetite, and eventual weight gain and/or obesity.

However, the Board points out that the Veteran has not been service-connected for any sleep disturbances caused by knee pain, either as part of his overall knee disability or as a separate disorder secondary to his knee disabilities.  In fact, the post-service record leading up to the initial treatment for sleep apnea in April 2015, was silent for reports of any sleep impairment due to knee pain.  Instead, the record showed either reports of sleep difficulty due to specific causes other than knee pain, such as head pain or coughing, or reports that sleep was "normal," "adequate," "okay," or "good."  See January 2005, August 2007, September 2007, October 2009, May 2013, September 2013, December 2013, March 2014, July 2014,
 either as part of his overall knee disability or as a separate disorder secondary to his knee disabilities.  In fact, the post-service record leading up to the initial treatment for sleep apnea in April 2015, was silent for reports of any sleep impairment due to knee pain.  Instead, the record showed either reports of sleep difficulty due to specific causes other than knee pain, such as head pain or coughing, or reports that sleep was "normal," "adequate," "okay," or "good."  See January 2005, August 2007, September 2007, October 2009, May 2013, September 2013, December 2013, March 2014, July 2014, and January 2015.  In fact, in August 2007, when the Veteran reported that he was unable to fall asleep some nights, he did not report knee pain as a cause or contributor and, in fact, denied joint concerns on a review of systems and stated that he "feels well physically."  When the Veteran sought treatment in April 2015 for sleep problems eventually diagnosed as OSA, he also affirmatively denied having significant pain that he wished to discuss with his provider.

Subsequent treatment records are equally silent for reports of sleep impairment or sleep disturbance due to knee pain.  In August 2015 and in February 2016, after receiving his OSA diagnosis and CPAP, the Veteran reported that the CPAP was "significantly helpful" for his well-being, that his sleep patterns were much improved, and he had "remarkable improvement in energy."  Notably, he did not report any continued sleep difficulty due to knee pain.  Thereafter, the Veteran either reported sleep difficulty unrelated to knee pain or reported that his sleep was "fine," "pretty good," or "okay."  See December 2018, September 2019, December 2019, March 2020, and October 2020 VA Treatment Notes.  In fact, the Board finds it particularly probative that even after the Veteran received a CPAP, he reported that he was sleeping well or that he had "good sleep," because there is no indication that any claimed chronic knee pain had resolved.  See, e.g., December 2021, March 2022, October 2022, December 2022 VA Treatment Note.  In other words, if the Veteran had sleep disturbances due to knee pain, it would be expected that those sleep disturbances would have continued even after receiving treatment for OSA absent resolution of the knee pain, which has not been asserted here.  However, there is no competent and credible evidence of sleep impairment due to knee pain, either prior or subsequent to the Veteran's diagnosed OSA. 

The Board takes issue with other aspects of the January 2022 and January 2023 private opinions.  For instance, the Board finds that the assertion that the Veteran led a sedentary lifestyle due to his knee pain post service is somewhat contradicted by the evidence of record.  The record affirmatively demonstrated that post service the Veteran played in multiple softball leagues (at a "very competitive level"), golfed regularly, skied, walked for exercise, went to the gym, and used a treadmill.  Regarding the assertion that the Veteran's knee pain caused sleep disturbance that led to an increased appetite, the Board notes that where weight or weight gain was discussed, the record shows that it was primarily the quality of the Veteran's diet at issue, including eating fast food regularly, drinking pop, and using alcohol.  See, e.g., April 2014, July 2018, October 2020, and February 2022 VA Treatment Notes.  In fact, the Veteran even reported a decreased appetite in September 2007 and, in February 2022, he experienced an intentional weight loss of six pounds in a two week period based on just a change in diet.  

The Board also notes that in attributing the Veteran's weight gain directly to his knee pain and a lack of physical activity, neither examiner (1) offered any discussion of nonservice-connected pain experienced by the Veteran post service or its potential impact on any decreased physical activity or sleep impairment; (2) explained why the Veteran's bilateral knee disability would have impaired the Veteran's ability to perform all types of physical activity, including swimming, particularly in light of the evidence showing that the Veteran played competitive softball and golfed; or, (3) accounted for the Veteran's significant weight gain in service prior to the onset of his knee problems.  Indeed, the private examiners' reliance on the timing of the Veteran's weight gain is misplaced as by their own admission, the Veteran also experienced significant weight gain prior to the onset of his knee disabilities.  Even so, absent a showing of causation, the fact that the Veteran had weight gain temporally after in
 post service or its potential impact on any decreased physical activity or sleep impairment; (2) explained why the Veteran's bilateral knee disability would have impaired the Veteran's ability to perform all types of physical activity, including swimming, particularly in light of the evidence showing that the Veteran played competitive softball and golfed; or, (3) accounted for the Veteran's significant weight gain in service prior to the onset of his knee problems.  Indeed, the private examiners' reliance on the timing of the Veteran's weight gain is misplaced as by their own admission, the Veteran also experienced significant weight gain prior to the onset of his knee disabilities.  Even so, absent a showing of causation, the fact that the Veteran had weight gain temporally after incurring his knee disabilities has no probative value; if that was sufficient, one could argue that the Veteran's esophageal obstruction treated in December 2020 was related to his knee disabilities simply because it occurred after the onset of knee disabilities over 15 years earlier.

Importantly, none of the foregoing clinical evidence, which essentially contradicts the private examiners' findings that the Veteran experienced sleep disturbances and weight gain due to chronic knee pain post service, was discussed by either private examiner.  Even further, neither examiner identified any clinical evidence or other evidence, specific to this Veteran, that was supportive of the conclusions offered.  Instead, the examiners' relied on the Veteran's self-reports which, unfortunately, the Board finds to be unreliable given the lack of such reports in the relevant record, especially where such reports would be expected.  As noted, the clinical record is lacking in reports of chronic knee pain, sleep disturbance caused by knee pain, an impaired ability to perform physical activity due to knee pain, or of weight gain due to an inability to exercise due to knee pain.  Thus, the private opinions are afforded no probative weight.

In contrast, a March 2022 VA examiner found that the Veteran's obesity was less likely as not the result of the Veteran's service-connected bilateral knee disability.  The examiner explained that the Veteran's knee disabilities would not preclude all forms of exercise and found that the medical records did not support that the Veteran's knee disabilities caused the Veteran's obesity.  The examiner explained that obesity was most commonly the result of a combination of excessive food intake and lack of physical activity, but that many factors could contribute to the development of obesity, including genetics, lifestyle factors, medications, and hormonal issues.  The Board finds the March 2022 VA opinion to be probative as it was based on a review of the record, supported by rationale, and consistent with the clinical evidence demonstrating that the Veteran's weight gain was mainly the result of diet choices and work schedules and affirmatively showing that the Veteran engaged in physical activities such as softball, golf, and walking.  See Nieves-Rodriguez v. Peake,?22 Vet. App. 295, 304?(2008).

To the extent that the Veteran contends that he developed OSA as a result of weight gain due to his service-connected bilateral knee disability, he is not competent to offer such an opinion.  The relationships between a knee disability and weight gain and the development of OSA, are medically complex because they require knowledge of internal physiological processes and knowledge of the interaction between anatomical relationships.  As the Veteran is not shown to have any relevant training or education, he is not competent to determine that his OSA was the result of obesity or weight gain that was due to a joint disability. Jandreau v. Nicholson,?492 F.3d 1372, 1377, 1377 n.4?(Fed. Cir. 2007). 

In sum, having considered the totality of the evidence in the relevant record, the Board finds the most probative evidence to be the clinical evidence, which showed that the Veteran's weight gain was due to lifestyle factors and that he was not precluded from exercise, and which is otherwise silent for complaints of sleep impairment or an impaired ability to exercise due to knee pain.  That evidence is supported by the March 2022 VA opinion, which the Board also finds probative.  In contrast, for the reasons discussed above, the Board finds the January 2022 and January 2023 private opinions to lack any probative value and the Veteran's assertions to be neither competent nor credible.  Accordingly, the Board concludes that the Veteran's weight gain and obesity were not caused by his service-connected knee disabilities.  Given that finding, the Board need not address relationship between obesity and sleep apnea because the Veteran's obesity has not been established as an intermediary cause here.  

As the evidence weighs against the claim, the benefit-of-the-doubt rule is inapplicable, and the appeal must be denied.  See 38 U.S.C. § 5107; 38 C.F.R. §§