Citation Nr: 20003602 Decision Date: 01/16/20 Archive Date: 01/15/20 DOCKET NO. 11-03 497 DATE: January 16, 2020 ORDER Entitlement to a 50 percent evaluation from February 22, 2009, for obstructive sleep apnea (OSA) with residuals of right pleuritis and right basal pneumonia with chronic obstructive pulmonary disease (COPD) is granted, subject to the laws and regulations governing the award of monetary benefits. Entitlement to an evaluation in excess of 50 percent for obstructive sleep apnea (OSA) with residuals of right pleuritis and right basal pneumonia with chronic obstructive pulmonary disease (COPD) from February 22, 2010 is denied. Entitlement to a total disability rating based on individual unemployability due to service-connected disabilities (TDIU) is granted. FINDINGS OF FACT 1. Treatment of the Veteran's OSA with residuals of right pleuritis and right basal pneumonia with COPD prior to February 22, 2010, and since April 25, 2006, required the use of a CPAP machine. 2. At no point has the Veteran's OSA been productive of chronic respiratory failure with carbon dioxide retention or cor pulmonale, nor has his obstructive sleep apnea necessitated a tracheostomy. 3. For the entire appellate time period, the Veteran meets the percentage requirements for TDIU. 4. Affording the benefit of the doubt ot the Veteran, the evidence of record demonstrates that his service-connected disabilities prevent him from securing or following a substantially gainful occupation. CONCLUSIONS OF LAW 1. The criteria for a 50 percent disability rating for OSA with residuals of right pleuritis and right basal pneumonia with COPD prior to February 22, 2010, but not before February 22, 2009, have been met. 38 U.S.C. §§ 1155, 5103, 5103A, 5107; 38 C.F.R. §§ 3.159, 3.321(a), 4.100, DC 6847. 2. The criteria for a disability rating in excess of a 50 percent rating for OSA with residuals of right pleuritis and right basal pneumonia with COPD from February 22, 2010, have not been met. 38 U.S.C. §§ 1155, 5103, 5103A, 5107; 38 C.F.R. §§ 3.159, 3.321(a), 4.100, DC 6847. 3. The criteria for TDIU on a schedular basis have been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 3.340, 3.341, 4.16(a). REASONS AND BASES FOR FINDINGS AND CONCLUSIONS Insert dates of service and jurisdictional information only where relevant to the adjudication of the issues on appeal. The Veteran served on active duty from February 1977 to June 1977. These matters come before the Board of Veterans' Appeals (Board) on appeal from August 2009 and September 2010 rating decisions of a Department of Veterans Affairs (VA) Regional Office (RO). In May 2018, the Board remanded the Veteran’s case for additional development. As to the Board’s May 2018 remand directives which ordered that pre-bronchodilator and post-bronchodilator be conducted, now associated with the Veteran’s claims file are VA examinations addressing the Veteran’s service-connected disabilities of sleep apnea as well as his respiratory conditions. See January 2019 VA examination(s). Significantly, the Board finds that the VA substantially complied with its remand directives as the pertinent testing was conducted as requested. Id. At the outset, the Board notes that disabilities due to sleep apnea are rated in accordance with the criteria under 38 C.F.R. § 4.97, Diagnostic Code (DC) 6847, and the Veteran’s disabilities due to right pleuritis and right basal pneumonia with chronic obstructive pulmonary disease (COPD) are rated in accordance with DC(s) 6600 through 6604. The controlling laws and regulations do not permit the assignment of separate disability ratings for disabilities that are rated under DC(s) 6600 through 6817 and 6822 through 6847. See 38 C.F.R. § 4.96(a). Thus, the Veteran's condition of obstructive sleep apnea with residuals of right pleuritis and right basal pneumonia with chronic obstructive pulmonary disease (COPD) has been evaluated under DC(s) 6003-6847, with a single disability rating assigned pursuant to the criteria under DC 6847, as it is to the Veteran’s greatest benefit rating him under that condition’s diagnostic code. See Butts v. Brown, 5 Vet. App. 532, 538 (1993). The Board acknowledges the Veteran’s letter dated June 2019 in which he states that the Board’s May 2018 decision did not address the issue of entitlement to an earlier effective date for his increased rating claim for his service-connected bipolar disorder. In its prior July 2017 decision, the Board adjudicated the issues of entitlement to an initial 50 percent rating for bipolar disorder, prior to December 24, 2014 (granted), as well as entitlement to a rating in excess of 30 percent for bipolar disorder, from December 24, 2014 (denied). Subsequently, the RO issued a July 2017 rating decision effectuating the Board’s July 2017 decision, and thereafter the Veteran filed a statement in support of his claim alleging that his effective date of service connection for his condition should be March 2009, as he had previously submitted a claim for Major Depressive Disorder on February 19, 2009. As to the Veteran’s claim for an earlier effective date, according to VA law, a claimant may not file, and the VA has no authority to adjudicate, a freestanding earlier effective date claim, as such a claim would violate the rule of finality. See Rudd v. Nicholson, 20 Vet. App. 296 (2006). Earlier effective date claims must arise on appeal from the rating decision granting the disputed effective date. Once an adjudication assigning an effective date becomes final, the finality of the effective date may only be overcome by a request for revision based on clear and unmistakable error (CUE). Accordingly, the Board finds that the Veteran’s earlier effective date claim for his service-connected bipolar disorder is not properly before it on appeal, and therefore the Board has no authority to adjudicate said claim. Increased Rating Disability evaluations are determined by the application of VA's Schedule for Rating Disabilities (Rating Schedule), 38 C.F.R. Part 4. The percentage ratings contained in the Rating Schedule represent, as far as can be practicably determined, the average impairment in earning capacity resulting from diseases and injuries incurred or aggravated during military service and the residual conditions in civil occupations. 38 U.S.C. § 1155; 38 C.F.R. §§ 3.321 (a), 4.1. Where there is a question as to which of two evaluations shall be applied, the higher evaluation will be assigned if the disability picture more nearly approximates the criteria required for that rating. Otherwise, the lower rating will be assigned. 38 C.F.R. § 4.7. Where entitlement to compensation has already been established and an increase in the disability rating is at issue, it is the present level of disability that is of primary concern. See Francisco v. Brown, 7 Vet. App. 55, 58 (1994). The Board will consider entitlement to staged ratings to compensate for times since filing the claim when the disability may have been more severe than at other times during the course of the claim on appeal. The relevant temporal focus for adjudicating an increased rating claim is on the evidence concerning the state of the disability from the time period one year before the claim was filed until VA makes a final decision on the claim. Fenderson v. West, 12 Vet. App. 119 (1999); Hart v. Mansfield, 21 Vet. App. 505 (2007). 1. Entitlement to an evaluation in excess of 30 percent prior to February 22, 2010 for obstructive sleep apnea with residuals of right pleuritis and right basal pneumonia with chronic obstructive pulmonary disease (COPD) The Veteran was first granted service connection for OSA as secondary to right pleuritis and right basal pneumonia with COPD in a July 2017 Board decision, subsequently effectuated by the RO’s July 2017 rating decision, increasing the Veteran’s disability rating for that condition to 50 percent effective February 22, 2010. As indicated, the controlling laws and regulations do not permit the combining of coexisting respiratory conditions, and therefore the RO evaluated the Veteran under DC 6603-6847 and assigned the Veteran a 50 percent disability rating as the medical records associated with the Veteran’s claims file dated May 13, 2010, indicated use of CPAP machine. The Veteran's obstructive sleep apnea is rated under DC 6603-6847. Under DC 6847, the minimum noncompensable rating is warranted for asymptomatic sleep apnea but with documented sleep disorder breathing. A 30 percent rating is warranted for persistent day-time hypersomnolence. A 50 percent rating is warranted for sleep apnea that requires the use of a breathing assistance device such as continuous airway pressure (CPAP) machine. The maximum 100 percent rating is warranted for chronic respiratory failure with carbon dioxide retention or cor pulmonale, or; requires tracheostomy. Id. Under DC 6603, a 10 percent rating is warranted when the FEV-1 is 71 to 80 percent predicted, or; FEV-1/FVC is 71 to 80 percent, or; DLCO (SB) is 66 to 80 percent predicted. A 30 percent rating is warranted when the FEV-1 is 56 to 70 percent predicted, or; the FEV-1/FVC is 56 to 70 percent, or; the DLCO (SB) is 56 to 65 percent predicted. A 60 percent rating is warranted when the FEV-1 is 40 to 55 percent predicted, or; FEV-1/FVC is 40 to 55 percent, or; DLCO (SB) is 40 to 55 percent predicted, or; maximum oxygen consumption of 15 to 20 ml/kg (with cardiorespiratory limit). A 100 percent rating is warranted for FEV-1 less than 40 percent of predicted value, or; FEV-1/FVC less than 40 percent, or; DLCO (SB) less than 40 percent predicted, or; maximum exercise capacity less than 15 ml/kg in oxygen consumption (with cardiac or respiratory limitation), or; cor pulmonale (right heart failure), or; right ventricular hypertrophy, or; pulmonary hypertension (shown by Echo or cardiac catheterization), or; episode(s) of acute respiratory failure, or; requires outpatient oxygen therapy. 38 C.F.R. § 4.97; Id. For evaluation purposes, the post-bronchodilator results are used unless they are poorer than the pre-bronchodilator results. 38 C.F.R. § 4.96, Note 5. Special provisions apply to diagnostic codes 6003 and 6004. PFTs are required to evaluate these conditions except: (i) When the results of a maximum exercise capacity test are of record and are 20 ml/kg/min or less. If a maximum exercise capacity test is not of record, evaluate based on alternative criteria; (ii) When pulmonary hypertension (documented by an echocardiogram or cardiac catheterization), cor pulmonale, or right ventricular hypertrophy has been diagnosed; (iii) When there have been one or more episodes of acute respiratory failure; or (iv) When outpatient oxygen therapy is required. 38 C.F.R. § 4.96 (d)(1). If the DLCO (SB) test is not of record, evaluate based on alternative criteria as long as the examiner states why the test would not be useful or valid in a particular case. 38 C.F.R. § 4.96 (d)(2). When the PFT's are not consistent with clinical findings, evaluate based on the PFT's unless the examiner states why they are not a valid indication of respiratory functional impairment in a particular case. 38 C.F.R. § 4.96 (d)(3). Post-bronchodilator studies are required when PFT's are done for disability evaluation purposes except when the results of pre-bronchodilator pulmonary function tests are normal or when the examiner determines that post-bronchodilator studies should not be done and states why. 38 C.F.R. § 4.96 (d)(4). When evaluating based on PFT's, use post-bronchodilator results in applying the evaluation criteria in the rating schedule unless the post-bronchodilator results were poorer than the pre-bronchodilator results. In those cases, use the pre-bronchodilator values for rating purposes. 38 C.F.R. § 4.96 (d)(5). When there is a disparity between the results of different PFT's (FEV-1, FVC, etc.), so that the level of evaluation would differ depending on which test result is used, use the test result that the examiner states most accurately reflects the level of disability. 38 C.F.R. § 4.96 (d)(6). If the FEV-1 and the FVC are both greater than 100 percent, do not assign a compensable evaluation based on a decreased FEV-1/FVC ratio. 38 C.F.R. § 4.96 (d)(7). The effective date of an award of increased compensation shall be the earliest date which it is ascertainable that an increase in disability has occurred, if the application is received within one year from such date; otherwise, it is the date of receipt of the claim. 38 U.S.C. § 5110 (a), (b)(2); 38 C.F.R. § 3.400 (o). Thus, the effective date of an award of increased compensation may be assigned up to one year prior to the date of claim, if an ascertainable increase in disability is established during that period. See Hazan v. Gober, 10 Vet. App. 511, 519 (1992); see also Hart v. Mansfield, 21 Vet. App. 505, 509-10 (2007) (noting that "the relevant temporal focus" in an increased rating claim is on "the state of the disability from the time period one year before the claim was filed until VA makes a final decision on the claim"). In evaluating the Veteran’s condition under DC 6847, in support of the Veteran’s claim for an increased rating in excess of a 30 percent rating for the period prior to February 22, 2010, are VA medical records which evidence that the Veteran was prescribed a CPAP machine for sleep apnea on April 25, 2006, which satisfies the 50 percent rating criteria under DC 6847. The Veteran also reports having to use the CPAP machine to sleep. See June 2006 SSA Questionnaire. Therefore, the Board finds it ascertainable that the Veteran’s service-connected disability did in fact increase in severity during the applicable one-year time period prior to the date of his increased rating claim in February 2010. During that same period, the Board finds no other evidence, medical or lay, to support a rating increase in excess of 50 percent for the Veteran’s OSA residuals of right pleuritis and right basal pneumonia with COPD. More specifically, the evidence of record does not support a finding that the Veteran’s claimed for condition ever met the next highest rating criteria under DC 6847 by resulting in chronic respiratory failure with carbon dioxide retention or cor pulmonale, or; requires tracheostomy. Nor does the evidence of record support a finding, for that period prior to February 22, 2010, that the Veteran’s condition ever met the next highest rating criteria under DC 6603 by resulting in FEV-1 is 40 to 55 percent predicted, or; FEV-1/FVC is 40 to 55 percent, or; DLCO (SB) is 40 to 55 percent predicted, or; maximum oxygen consumption of 15 to 20 ml/kg (with cardiorespiratory limit). See April 2009 VA examination (“Compared to 7/20/2007 there has been a 910cc increase in pre-bronchodilator FEV1, consistent with improvement in obstructive lung disease."). The Board acknowledges that the Veteran submitted a December 2009 private treatment record from Dr. MEF where he stated that with respect to the Veteran’s claimed for condition, “he suffers from chronic pulmonary disease which has worsened. He has frequent[] episodes of asthma attacks. He suffer[s] airways tighten, inflame and fill with mucus including coughing, especially at night, wheezing, shortness of breath, chest tightness, pain and pressure. He also suffer[s] from sleep apnea with the following symptoms, he wake[s] up at night due to shortness of breath, have loud snoring, have difficulty falling asleep, difficulty remembering and feeling sleeping in the morning. His right side of his heart has enlarged.” The Board affords Dr. MEF’s private medical opinion less probative weight for the purposes of rating the Veteran’s claimed for disability as it is unclear whether any sort of objective medical testing of the Veteran’s respiratory conditions, such as PFTs or chest x-rays, were conducted. The Board affords the April 2009 VA examination the most probative weight for the period prior to February 22, 2010, as the VA examiner conducted PFTs as well as chest x-rays in finding that the Veteran’s heart was of normal size, and that per the associated PFTs, his service-connected respiratory condition had actually improved since his last 2007 VA examination assessing the condition. The Board has considered the Veteran's lay statements of record that a higher disability rating is warranted for his respiratory disability. Specifically, the Veteran alleges that his claimed for condition results in chronic respiratory failure. See July 2019 correspondence. The Veteran is competent to report symptomatology relating to his respiratory disability to the extent it requires only personal knowledge as it comes to him through his senses. Layno v. Brown, 6 Vet. App. 465, 470 (1994). He is not, however, competent to identify a specific level of disability relating such to the appropriate Diagnostic Codes. The Board finds that the question of the severity of the Veteran’s respiratory disability is medically complex in nature. Woehlaert v. Nicholson, 21 Vet. App. 456 (2007). To the extent that the Veteran alleges greater severity, the Board finds that the probative value of his allegations is outweighed by the medical findings of record. Competent medical evidence concerning the nature and extent of the Veteran's disability has been provided by VA examiners during the current appeal period, and it is found that they provided relevant medical findings in conjunction with the examinations. In this regard, the medical findings (as provided in the examination reports) directly address the evaluation criteria for this disability. Ultimately the probative and objective medical evidence of record does not support a finding that the Veteran’s OSA manifested with chronic respiratory failure with carbon dioxide retention or cor pulmonale, or required tracheostomy, during the period prior to February 22, 2010, and therefore he is not entitled to a higher rating of 100 percent under DC 6847. Additionally, the Board notes that it also considered as to whether the Veteran’s service-connected condition warranted a higher rating by evaluating him under DC 6603; however, the record does not ever support a finding that the Veteran meets the next highest rating criteria of 60 percent during the period prior to February 22, 2010, as his condition did not ever manifest with FEV-1 is 40 to 55 percent predicted, or; FEV-1/FVC is 40 to 55 percent, or; DLCO (SB) is 40 to 55 percent predicted, or; maximum oxygen consumption of 15 to 20 ml/kg (with cardiorespiratory limit). Thus, after a review of the record for the period prior to February 22, 2010, the Board finds that the Veteran's OSA with residuals of right pleuritis and right basal pneumonia with COPD meets the rating criteria under DC 6847 for a 50 percent rating prior to February 22, 2010, but not before February 22, 2009, as it is ascertainable that the Veteran’s respiratory condition required the use of a CPAP machine prior to the date of his increased rating claim. Thus, an increased rating for OSA with residuals of right pleuritis and right basal pneumonia with COPD as of February 22, 2009 is granted at 50 percent. 2. Entitlement to an evaluation in excess of 50 percent for obstructive sleep apnea with residuals of right pleuritis and right basal pneumonia with chronic obstructive pulmonary disease (COPD) from February 22, 2010 For the period from February 22, 2010, the Board finds that the pertinent evidence of record does not support a finding that would warrant an increase in the Veteran’s disability rating for his condition of OSA with residuals of right pleuritis and right basal pneumonia with COPD. As previously mentioned, the Veteran’s case was remanded in May 2018 by the Board for additional development in order to obtain pre-bronchodilator and post-bronchodilator PFTs which are now associated with the Veteran’s claims file. See January 2019 VA examination(s). In conducting the examinations, it is important to note that the VA examiner reviewed the Veteran’s previous VA examinations of record. As to the Veteran’s OSA, the VA examiner did not find that the condition manifests with symptoms in the next highest rating criteria under DC 6847, namely chronic respiratory failure with carbon dioxide retention or cor pulmonale, or requires tracheostomy. Id. Additionally, in evaluating the Veteran’s claimed for condition under DC 6603’s next highest rating criteria, the VA examiner did not find that the Veteran’s condition manifests with symptoms of FEV-1 40 to 55 percent predicted, or; FEV-1/FVC 40 to 55 percent, or; DLCO (SB) 40 to 55 percent predicted, or; maximum oxygen consumption of 15 to 20 ml/kg (with cardiorespiratory limit) to warrant a 60 percent rating increase. Rather, the January 2019 VA examination’s PFTs revealed FEV-1 of 83 percent predicted; FEV-1 noted by the VA examiner as being the test which most accurately reflects the Veteran’s disability. Id. Again, the Board acknowledges the Veteran's lay statements of record that a higher disability rating is warranted for his respiratory disability, as he contends that his condition results in chronic respiratory failure. See July 2019 correspondence. Here the Board cannot consider these statements probative on the issue, as the question of severity of the Veteran’s respiratory condition is of a complex medical nature. See Woehlaert v. Nicholson, 21 Vet. App. 456 (2007). The Board has considered whether any other Diagnostic Codes related to disabilities of the respiratory system would provide the Veteran with a higher disability rating. However, the evidence of record does not reflect that the symptoms would warrant a higher rating under a different Diagnostic Code. See 38 C.F.R. § 4.71a. As the Veteran already has the highest possible schedular disability rating, given his symptoms, for the period from February 22, 2010 for his condition of OSA with residuals of right pleuritis and right basal pneumonia with COPD, the appeal for a disability rating in excess of 50 percent is denied. 3. Entitlement to a total disability rating based on individual unemployability due to service-connected disabilities (TDIU) Total disability will be considered to exist where there is present any impairment of mind and body that is sufficient to render it impossible for the average person to follow a substantially gainful occupation. 38 C.F.R. § 3.340. Total disability ratings for compensation may be assigned, where the schedular rating is less than total, when the disabled person is unable to secure or follow a substantially gainful occupation as a result of service-connected disabilities, provided that the Veteran meets the schedular requirements. If there is only one service-connected disability, this disability should be rated at 60 percent or more; if there are two or more disabilities, at least one should be rated at 40 percent or more with sufficient additional service-connected disability to bring the combination to 70 percent or more. 38 C.F.R. § 4.16 (a). To meet the requirement of "one 60 percent disability" or "one 40 percent disability," the following will be considered as one disability: (1) disability of one or both lower extremities, including the bilateral factor, if applicable; (2) disabilities resulting from one common etiology; (3) disabilities affecting a single body system; (4) multiple injuries incurred in action; and (5) multiple disabilities incurred as a prisoner of war. Id. Substantially gainful employment is defined as work which is more than marginal and which permits the individual to earn a living wage. Moore v. Derwinski, 1 Vet. App. 356 (1991). Where these percentage requirements are not met, entitlement to benefits on an extraschedular basis may be considered when the Veteran is unable to secure and follow a substantially gainful occupation by reason of service-connected disabilities, and consideration is given to the Veteran's background including his or her employment and educational history. 38 C.F.R. § 4.16 (b). The Board does not have the authority to assign an extraschedular total disability rating for compensation purposes based on individual unemployability in the first instance. Bowling v. Principi, 15 Vet. App. 1 (2001). In determining whether unemployability exists, consideration may be given to the Veteran's level of education, special training, and previous work experience, but it may not be given to his or her age or to any impairment caused by nonservice-connected disabilities. 38 C.F.R. §§ 3.341, 4.16, 4.19. Marginal employment is not considered substantially gainful employment. 38 C.F.R. §§ 3.340, 4.16(a). Substantially gainful employment means, essentially, that the work provides income above the poverty level established by the United States Department of Commerce, without benefit of protected family employment or a sheltered workshop. 38 C.F.R. § 4.16 (a). Factors to be considered in determining entitlement to TDIU include, but are not limited to, employment history, educational achievement, and vocational attainment. 38 C.F.R. § 4.16 (b). The Board notes that the Veteran meets schedular for a TDIU for the entire period on appeal. To point, in lieu of being granted an increase for the period prior February 22, 2010, but not before February 22, 2009, for the Veteran’s service-connected OSA with residuals of right pleuritis and right basal pneumonia with COPD, the Veteran is rated at 50 percent for the aforesaid disability from February 22, 2009 to present; meeting the requirement that when combined, at least one service-connected disability must be rated at 40 percent. Additionally, the Veteran’s service-connected bipolar disorder is rated at 50 percent from February 22, 2010, and at 30 percent from December 24, 2014; meeting the requirement that when combined, the combination of the service-connected disabilities must equate to a 70 percent rating or higher. As such, the Veteran meets the percentage requirements for TDIU for the entire period on appeal. 38 C.F.R. § 4.16 (a). The Board must now consider whether the evidence reflects that the Veteran's service-connected disabilities render him unemployable. Per the evidence of record, in support of the Veteran’s claim for a TDIU, is a letter from the US Postal Service, indicated that that the Veteran “was deemed unfit to work since May 15, 2006.” Prior to that determination being made, the Veteran was evaluated by Dr. DD, at the request of the U.S. Postal Service, and it was found that the Veteran should remain on medical leave due to “severe depressive symptoms with psychotic features… has some aggressive ideas and active psychotic symptoms which may be exacerbated by working environment stress.” See April 2006 private medical examination and opinion. Ultimately, the Veteran retired from the U.S. Postal Service, and was awarded disability benefits by the Social Security Administration, primarily due to his currently diagnosed and service-connected acquired psychiatric disorder. Here, the Board finds that the evidence of record corroborates that the Veteran has not maintained substantially gainful employment since retiring from the US. Postal Service in 2006, and that said retirement was due in large part to the Veteran’s service-connected acquired psychiatric disorder. As to the Veteran’s lay testimony in support of his claim for a TDIU, he reports having lost his driver’s license to drive heavy vehicles due to neuropathy. See June 2006 SSA Questionnaire. The Veteran also claims that he has “virtually no social life; I am virtually isolated in the community, unable to form effective social relationships.” See November 2016 VA Form 9. The Veteran also states that he was a fire fighter and could no longer perform his duties due to his condition. He also asserted that the VA also failed to address his other service-connected conditions, as his Major Depressive Disorder by itself, totally incapacitates him. See July 2019 Correspondence. Also in support of the Veteran’s claim is a medical determination by a VA examiner that the Veteran’s service-connected sleep apnea condition impacts his ability to work in that the Veteran reports “despite using CPAP machine, he continues with daytime hypersomnolence. Veteran reports he remains asleep in the traffic lights while driving.” See January 2019 VA examination. Evidence weighing against the Veteran’s claim for a TDIU includes a recent VA examination of the Veteran’s respiratory condition, not including sleep apnea, in which the Examiner noted that the Veteran’s respiratory conditions, to include sleep apnea, does not have a functional impact on his ability to work. See January 2019 VA examination. Also associated with the Veteran’s claims file is a negative medical opinion provided by Dr. D F-D who states that the “Veteran is not unemployable on account of mental condition… Veteran’s mental disorder symptoms are controlled by continuous medication.” Here, the Board affords Dr. D F-D’s negative medical opinion less probative weight as it does not take into consideration the Veteran’s entire medical history, to include that period of time when his acquired psychiatric disorder rendered him unfit to work for the U.S. Postal Service. See 38 C.F.R. § 4.1, 4.2; Schafrath v. Derwinski, 1 Vet. App. 589 (1991). The Board has considered the Veteran's employment history, education and the evidence of record regarding the service-connected disabilities. Resolving any doubt in his favor, the Board finds that the Veteran's service-connected OSA with residuals of right pleuritis and right basal pneumonia with COPD and bipolar disorder result in an inability to obtain or retain substantially gainful employment based on the Veteran's past work experience. As such, the Board concludes that entitlement to TDIU is warranted. K. J. ALIBRANDO Veterans Law Judge Board of Veterans’ Appeals Attorney for the Board S.R. Fey, 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.