Citation Nr: 21071672 Decision Date: 12/01/21 Archive Date: 12/01/21 DOCKET NO. 19-04 776 DATE: December 1, 2021 ORDER Entitlement to a 70 percent rating, but no higher, for service connection for post-traumatic stress disorder (PTSD) is granted. REMANDED Entitlement to service connection for a low back disability is remanded. Entitlement to service connection for coronary artery disease (CAD) is remanded. Entitlement to service connection for diabetes mellitus, to include as secondary to CAD, is remanded. Entitlement to service connection for a disability characterized by chronic fatigue and joint pain, to include as due to an undiagnosed illness, is remanded. Entitlement to service connection for sleep apnea, to include as secondary to PTSD, is remanded. Entitlement to total disability based on individual unemployability (TDIU) is remanded. FINDING OF FACT Throughout the period on appeal, the Veteran's PTSD has been manifested by occupational and social impairment, with deficiencies in most areas, such as work, school, family relations, judgment, thinking, or mood. CONCLUSION OF LAW Beginning January 29, 2016, the criteria for entitlement to a disability evaluation of 70 percent, but no higher, for PTSD have been met. 38 U.S.C. §§ 1155, 5107; 38 C.F.R. §§ 4.1, 4.2, 4.7, 4.130, Diagnostic Code 9411. REASONS AND BASES FOR FINDING AND CONCLUSION The Veteran served on active duty in the United States Army from June 1985 to October 1985 and from September 1990 to August 1991. This matter comes before the Board of Veterans' Appeals (Board) on appeal from September 2016, October 2017, and January 2019 rating decisions by a Department of Veterans Affairs (VA) Regional Office (RO). In March 2021, the Veteran testified before the undersigned at a hearing. A transcript of his testimony has been associated with the claims file. Increased Rating The RO granted service connection for PTSD in a January 2019 rating decision, which assigned an initial rating of 70 percent from January 29, 2016, and a 30 percent rating from January 4, 2019. The Veteran contends that he is entitled to a higher disability rating. As an initial matter, the Board notes that the RO has characterized the issues on appeal as whether the Veteran is entitled to higher disability ratings, as well as earlier effective dates for the grant of service connection and the 30 percent rating. However, it appears that the RO has misconstrued the Veteran's intent in filing this appeal. To that end, based on his notice of disagreement, substantive appeal, and hearing testimony, he instead appears to be arguing that he is entitled to a higher disability rating throughout the entire appeal period and that the RO should not have staged his rating for PTSD, as opposed to arguing that he is entitled to earlier effective dates for service connection or a 30 percent rating. As such, the Board has recharacterized the issues on appeal to reflect this intent. Disability ratings are determined by evaluating the extent to which a veteran's service-connected disability adversely affects his or her ability to function under the ordinary conditions of daily life, including employment, by comparing his or her symptomatology with the criteria set forth in the Schedule for Rating Disabilities. The percentage ratings represent as far as can practicably be determined the average impairment in earning capacity resulting from such diseases and injuries and the residual conditions in civilian occupations. Generally, the degree of disabilities specified are considered adequate to compensate for considerable loss of working time from exacerbation or illness proportionate to the severity of the several grades of disability. 38 U.S.C. § 1155; 38 C.F.R. § 4.1. Separate diagnostic codes identify the various disabilities and the criteria for specific ratings. If two disability evaluations are potentially applicable, the higher evaluation will be assigned to the disability picture that 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. However, the evaluation of the same disability under various diagnoses, known as pyramiding, is to be avoided. 38 C.F.R. § 4.14. Where it is not possible to distinguish between the effects of a non-service-connected condition and a service-connected disability, the benefit of the doubt goes to the veteran so that all symptoms from each condition are considered with respect to disability evaluations. Mittleider v. West, 11 Vet. App. 181 (1998). Where, as here, entitlement to service connection 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. Francisco v. Brown, 7 Vet. App. 55, 58 (1994). However, staged ratings are appropriate for an increased rating claim if the factual findings show distinct time periods where the service-connected disability exhibited symptoms that would warrant different ratings. See Hart v. Mansfield, 21 Vet. App. 505 (2007). In deciding claims, it is the Board's responsibility to evaluate the entire record on appeal. See 38 U.S.C. § 7104(a). Although the Board has an obligation to provide reasons and bases supporting this decision, there is no need to discuss each piece of evidence submitted by the appellant or on his behalf. See Gonzales v. West, 218 F.3d 1378 (Fed. Cir. 2000). Rather, the Board's analysis below will focus specifically on what evidence is needed to substantiate the claim and what the evidence in the claims file shows, or fails to show, with respect to the claim. See Timberlake v. Gober, 14 Vet. App. 122, 128-30 (2000). The Veteran's PTSD is rated under the General Rating Formula for Mental Disorders. 38 C.F.R. § 4.130. Under the General Rating Formula, a noncompensable disability rating is warranted where a mental condition has been formally diagnosed, but symptoms are not severe enough either to interfere with occupational and social functioning or to require continuous medication. Id. A 10 percent disability rating is available for occupational and social impairment due to mild or transient symptoms which decrease work efficiency and ability to perform occupational tasks only during periods of significant stress, or where symptoms are controlled by continuous medication. Id. A 30 percent disability rating requires occupational and social impairment with occasional decrease in work efficiency and intermittent periods of inability to perform occupational tasks (although generally functioning satisfactorily, with routine behavior, self-care, and conversation normal), due to such symptoms as: depressed mood, anxiety, suspiciousness, panic attacks (weekly or less often), chronic sleep impairment, and mild memory loss (such as forgetting names, directions, or recent events). Id. A 50 percent disability rating is warranted where the disorder is manifested by occupational and social impairment with reduced reliability and productivity due to such symptoms as flattened affect; circumstantial, circumlocutory, or stereotyped speech; panic attacks more than once a week; difficulty in understanding complex commands; impairment of short- and long-term memory (e.g., retention of only highly learned material, forgetting to complete tasks); impaired judgment; impaired abstract thinking; disturbances of motivation and mood; difficulty in establishing and maintaining effective work and social relationships. Id. A 70 percent disability rating is warranted where the disorder is manifested by occupational and social impairment with deficiencies in most areas, such as work, school, family relations, judgment, thinking or mood, due to such symptoms as suicidal ideation; obsessional rituals which interfere with routine activities; speech that is intermittently illogical, obscure, or irrelevant; near-continuous panic or depression affecting the ability to function independently, appropriately, and effectively; impaired impulse control, such as unprovoked irritability with periods of violence; spatial disorientation; neglect of personal appearance and hygiene; difficulty in adapting to stressful circumstances, including work or a work-like setting; and an inability to establish and maintain effective relationships. Id. A 100 percent disability rating is warranted when there is a total occupational and social impairment, due to such symptoms as persistent delusions or hallucinations; grossly inappropriate behavior; persistent danger of hurting self or others; intermittent inability to perform activities of daily living (including maintenance of minimal personal hygiene); disorientation to time and place; memory loss for names of close relatives, own occupation, or own name. Id. A veteran "may only qualify for a given disability rating under § 4.130 by demonstrating the particular symptoms associated with that percentage, or others of similar severity, frequency, and duration." Vazquez-Claudio v. Shinseki, 713 F.3d 112, 117 (Fed. Cir. 2013). Symptoms listed in the General Rating Formula serve as examples of the type and degree of symptoms, or their effects, that would justify a particular rating. They are not intended to constitute an exhaustive list. Mauerhan v. Principi, 16 Vet. App. 436, 442-44 (2002). Before determining the appropriate rating for the Veteran's PTSD, the Board will first review the relevant evidence in the record throughout the period on appeal. The Veteran's VA treatment records reflect that he has undergone extensive mental health treatment due various PTSD symptoms. For instance, he reported to a VA primary care provider that he was feeling extremely distant or cut off from others, quite a bit emotionally numb, and quite a bit irritable or angry in April 2016. Likewise, in a May 2017 mental health nursing note, he reported that he was depressed nearly every day, had little interest in doing things, and that he felt anxiety, anger, and irritability every day. He reported at a June 2017 mental health telehealth appointment that he avoided large crowds, had unprovoked tantrums, had trouble focusing, and did not find pleasure in hunting or fishing anymore. The Veteran began attending therapy more regularly in February 2018. In a February 2018 VA telehealth mental health intake note, he reported that he was not close to his siblings and that he had panic attacks, although his impulse control had improved. A depression screening indicated symptoms of moderately severe depression. At a June 2018 VA mental health appointment, he reported that he was always depressed and sought advice from his therapist on how to work on issues related to work and anger because he got "angry easily," including at his wife and employees of his business. At a July 2018 appointment, he asked for help to work on issues related to feeling depressed, anxious, and unenergetic and indicated that his depressive symptoms had increased since his last appointment. At a November 2018 appointment, he reported that he had recently had an angry outburst at an employee. Additionally, the Veteran was evaluated by Dr. L., a private doctor, in a January 2018 private evaluation. Dr. L.'s report indicated that the Veteran's mood was depressed and that he endorsed feelings of disappointment, confusion, anger, fear, and depression in the past week. His present complaints included frequently reexperiencing trauma, nightmares, avoidance behaviors, a depressed mood, a loss of interest in usually enjoyable activities, diminished energy, problems concentrating, and difficulty remembering simple things. Dr. L. indicated that his symptoms of depression were secondary to his PTSD and that his PTSD symptoms had worsened as he aged. Dr. L. also stated that the Veteran's PTSD symptoms affected his ability to run his pest control business efficiently and cope with the demands of his customers. Based on his examination, Dr. L. reported that he displayed symptoms including forgetting names, suspiciousness, depressed mood, near-continuous depression affecting his ability to function independently, appropriately and effectively, disturbances of motivation and mood, impaired judgment, mild memory loss, forgetting recent events, chronic sleep impairment, panic attacks more than once a week, difficulty adapting to stressful circumstances, difficulty in adapting to work, difficulty adapting in a worklike setting, and difficulty in establishing and maintaining effective work and social relationships. The Veteran also underwent a VA examination in January 2019 with respect to the nature, severity, and etiology of his PTSD. At that examination, the VA examiner noted that the Veteran had diagnoses of PTSD, major depressive disorder, and generalized anxiety disorder. The VA examiner stated that the symptoms of each diagnosis were distinguishable, but as rationale merely stated that his anxiety and depression were related to heart problems, while his PTSD resulted from his deployment. Confusingly, however, the VA examiner stated that his symptoms of PTSD included symptoms of anxiety and a depressed mood. She also stated that he exhibited suspiciousness, chronic sleep impairment, disturbances and mood or motivation. Ultimately, she opined that his symptoms were consistent with occupational and social impairment due to mild or transient symptoms. It does not appear that she reviewed or addressed Dr. L.'s private evaluation from January 2018. Having carefully reviewed the most relevant evidence in the record, the Board finds that the evidence supports a 70 percent rating, but no higher, for PTSD throughout the period on appeal. To that end, the most competent, credible evidence indicates that he has continuously displayed symptoms consistent with a 70 percent rating, such as near-continuous depression, impaired impulse control, difficulty in adapting to stressful circumstances, and the inability to establish and maintain effective relationships. Although the January 2019 VA examination report indicated that he had only mild, transient symptoms of PTSD and that his symptoms of anxiety and depression were distinguishable from his PTSD symptoms, the VA examiner's opinions are entitled to little, if any, probative value. In this regard, the VA examiner did not provide an explanation as to why his symptoms of depression and anxiety were distinguishable from his PTSD, or address Dr. L.'s report, which indicated that his depression symptoms overlapped with his PTSD symptoms. Moreover, the January 2019 VA examiner's report is internally inconsistent, as it states that symptoms of anxiety and depression are distinguishable from PTSD symptoms but also indicates that his symptoms of PTSD include anxiety and a depressed mood. Resolving all reasonable doubt in favor of the Veteran, the Board finds that his symptoms of non-service-connected generalized anxiety disorder and major depressive disorder cannot be distinguished from his symptoms of PTSD. See Mittleider, 11 Vet. App. at 181. Furthermore, the VA examiner did not sufficiently address the Veteran's contemporaneous VA treatment records, which reflect additional symptoms, such as difficulty adapting to stressful circumstances, impaired impulse control, and the inability to establish and maintain effective relationships. On the other hand, the more probative evidence of record indicates that the Veteran struggles with angry outbursts, frequent feelings of depression that limits his ability to function effectively, and difficulty dealing with stress. In recognition of this fact, the Board finds that his symptoms are more consistent with a 70 percent rating. The Board has also considered whether a rating in excess of 70 percent is available at any point during the period on appeal. However, the record does not suggest that the Veteran's ability to interact with others or engage socially has been totally impaired. Specifically, although the evidence suggests that he has difficulty controlling his impulses, handling stressful situations, and maintaining relationships with others, there are no clinical records indicating that he exhibits the symptoms indicative of a 100 percent rating for PTSD. For instance, there are no clinical records indicating that he is unable to perform activities of daily living, presents a persistent danger of hurting himself or others, or exhibits memory loss for names of close relatives or his own names. The record is devoid of any reports of auditory or visual hallucinations or delusions, grossly inappropriate behavior, disorientation to time or place, or gross impairment in thought process or communication. As such, the Board finds that the preponderance of the evidence shows a disability profile that more closely approximates the criteria for a 70 percent rating, effective January 29, 2016. REASONS FOR REMAND 1. Low back The Veteran argues that he has a current back disability that was caused by his service. More specifically, he testified at his March 2021 hearing that he was a member of an ordnance company that would carry heavy gear, which bothered his back. He stated that he did not report to sick call during service because it was 40 miles away from where he was stationed and treated his back pain with Tylenol instead. After service, he reported that he sought treatment from a doctor for the back pain in 1991 and was told that he had a slipped disc. Several years later, he sought medical attention when the back pain worsened. Turning to this matter, the Board notes that the Veteran has a current diagnosis of degenerative disc disease of the lumbar spine. The next question is thus whether there was an in-service disease or injury that occurred. In this regard, the Board acknowledges that the Veteran's service treatment records do not contain any specific notes regarding diagnosis of or treatment for a low back disability. However, for combat veterans, as defined under 38 U.S.C. § 1154(b), lay evidence alone can establish the in-service element of service connection, if consistent with the circumstances, conditions, or hardships of such service, even if there is no official record. 38 C.F.R. § 3.304(d). This is commonly referred to as the "combat presumption." 38 U.S.C. § 1154(b) does not establish service connection for a combat veteran, but rather aids him in relaxing the adjudicative evidentiary requirements for determining what happened in service. Clyburn v. West, 12 Vet. App. 296, 303 (1999). When a veteran has not received a medal indicative of combat, the Board must determine on a case-by-case basis whether he participated in combat with the enemy. VAOPGCPREC 12-99 (Oct. 18, 1999) (combat determination should be made on a case-by case basis where there is no medal specifically indicating combat service). Evidence submitted to support a claim that a veteran engaged in combat may include the veteran's own statements and an "almost unlimited" variety of other types of evidence. Gaines v. West, 11 Vet. App. 353, 359 (1998). Receiving enemy fire or firing on an enemy can constitute participation in combat. Sizemore v. Principi, 18 Vet. App. 264 (2004). Here, the Veteran has not received any awards indicative of combat service. As set forth above, however, he is service connected for PTSD. Service connection was awarded due to his service in Southwest Asia during Operation Desert Storm, where he was under attack from missiles and witnessed medivacs of injured soldiers leaving the battlefield. The above reflects that the Veteran engaged in combat during service. This finding that the Veteran engaged in combat is significant because it allows him to use "satisfactory lay or other evidence" to establish that he was injured or incurred or aggravated a disability while on active duty, even in cases where there is no official record that such injury or disability occurred. Reeves v. Shinseki, 682 F.3d 988, 998 (Fed. Cir. 2012) (citing 38 U.S.C. § 1154(b)). At this juncture, however, the Board cannot adjudicate the claim on its merits, because there is insufficient medical evidence in the record with respect to the etiology of his current low back disability. To that end, when VA undertakes to provide an examination or obtain a medical opinion, it must ensure that the examination or opinion is adequate. Barr v. Nicholson, 21 Vet. App. 303, 312 (2007). If an examination report is inadequate or does not contain sufficient detail, the Board is required to return the report in a remand. See Bowling v. Principi, 15 Vet. App. 1, 12 (2001). The RO afforded the Veteran a VA examination with respect to the etiology of his low back disability in August 2016. In the accompanying examination report, the VA examiner stated that service treatment records were silent for a back condition before opining that there was insufficient evidence to warrant or confirm a diagnosis of a back condition in service. The examiner ultimately opined that his current low back disability was more likely than not caused by or related to degenerative processes. In offering this rationale, however, the examiner did not discuss the Veteran's lay contentions or his combat service in Southwest Asia. An opinion is inadequate if it does not consider all relevant evidence of record, including lay evidence. Nieves-Rodriguez v. Peake, 22 Vet. App. 295 (2008). As such, remand is necessary to obtain an addendum medical opinion regarding the etiology of his low back disability. 2. CAD and Diabetes The Veteran has argued that his currently diagnosed CAD is related to his service in Desert Storm, including as due to exposure to burn pits, immunizations, or Bromide tablets. In September 2017, the RO afforded the Veteran with a VA examination regarding the etiology of his CAD. In the examination report, the examiner rendered a negative nexus opinion. The only rationale for this opinion, however, was, "I, personally, have no knowledge at this time [of] any [heart] conditions that could be caused by service in SWA." This opinion is conclusory and contains no supporting rationale, such as citations to the record or relevant medical research. An opinion that is conclusory or that does not provide a sufficiently detailed rationale is inadequate. Stefl v. Nicholson, 23 Vet. App. 320 (2007). Accordingly, remand is necessary to obtain an addendum medical opinion. The Board also notes that the Veteran's VA treatment records indicate that his diabetes mellitus and his heart condition are related to each other. As such, the record has raised the issue of whether service connection is warranted for diabetes secondary to CAD. As the issue of CAD has been remanded for further development, readjudication of the diabetes mellitus issue must be deferred as well. Harris v. Derwinski, 980 F.2d 37 (Fed. Cir. 1990). 3. Fatigue and joint pain The Veteran contends that he is entitled to service connection for chronic fatigue syndrome due to his service in Southwest Asia. He argues that, although he has not been diagnosed with chronic fatigue syndrome by a doctor, he has severe joint pain in his hands, knuckles, knees, ankles, shoulders, elbows, and back, and is tired at all times. Service connection may be warranted for Persian Gulf veterans who exhibit objective indications of a qualifying chronic disability that became manifest during the Persian Gulf War or to a degree of 10 percent or more. See 38 U.S.C. § 1117(a)(1)(A); 38 C.F.R. § 3.317(a). For purposes of 38 C.F.R. § 3.317, there are three types of "qualifying chronic disabilities": (1) an undiagnosed illness; (2) a medically unexplained chronic multi-symptom illness; and (3) a diagnosed illness that the Secretary determines warrants a presumption of service connection. An "undiagnosed illness" is defined as a condition that by history, physical examination, and laboratory tests cannot be attributed to a known clinical diagnosis. In the case of claims based on an undiagnosed illness under 38 U.S.C. § 1117 and 38 C.F.R. § 3.317, unlike those for direct service connection, there is no requirement that there be competent evidence of a nexus between the claimed illness and service. See Gutierrez v. Principi, 19 Vet. App. 1, 8-9 (2004). Further, lay persons are competent to report objective signs of illness. Id. To determine whether the undiagnosed illness is manifested to a degree of 10 percent or more, the condition must be rated by analogy to a disease or injury in which the functions affected, anatomical location, or symptomatology are similar. See 38 C.F.R. § 3.317(a)(5). In addition, service connection may be granted for objective indications of a chronic disability resulting from an illness or combination of illnesses manifested by one or more signs or symptoms, to include, but not limited to, fatigue, signs of symptoms involving skin, headaches, muscle pain, joint pain, neurologic signs or symptoms, neuropsychologic signs or symptoms, signs or symptoms involving the respiratory system (upper or lower), sleep disturbances, gastrointestinal signs or symptoms, cardiovascular signs or symptoms, abnormal weight loss, or menstrual disorders. 38 U.S.C. § 1117; 38 C.F.R. § 3.317. The illness must not be attributed to any known clinical diagnosis by history, physical examination, or laboratory tests. See 38 C.F.R. § 3.317(a)(1)(i). A "chronic disability" for purposes of 38 U.S.C. § 1117 is one that has existed for six months or more, including disabilities that exhibit intermittent episodes of improvement and worsening over a six-month period. Additionally, the term "MUCMI" refers to a diagnosed illness without conclusive pathophysiology or etiology and that is characterized by overlapping symptoms and signs and has features such as fatigue, pain, disability out of proportion to physical findings, and inconsistent demonstration of laboratory abnormalities. 38 C.F.R. § 3.317(a)(2)(ii). Examples of MUCMIs include chronic fatigue syndrome, fibromyalgia, and functional gastrointestinal disorders (excluding structural gastrointestinal disabilities). 38 C.F.R. § 3.317(a)(2)(B). The Veteran had qualifying service in the Persian Gulf. It does not appear that the Veteran has been diagnosed with chronic fatigue syndrome. Nonetheless, it is still possible that his symptoms of fatigue and joint pain could be related to an undiagnosed illness or some other disability. As such, the Board has broadened the claim on appeal into a claim for a disability characterized by chronic fatigue and joint pain, however diagnosed, to recognize this fact. See Clemons v. Shinseki, 23 Vet. App. 1 (2009); Brokowski v. Shinseki, 23 Vet. App. 79 (2009). As set forth earlier, the Veteran was afforded various VA examinations in August 2016. At that time, he was evaluated for chronic fatigue syndrome. Significantly, the VA examiner opined that there was insufficient evidence to warrant or confirm a diagnosis of chronic fatigue syndrome, and that no condition was diagnosis. However, the VA examiner did not discuss whether the Veteran's symptoms of fatigue and joint pain were symptoms of an undiagnosed illness. As such, the VA examiner failed to discuss all raised theories of entitlement, and remand is necessary. On remand, the examiner is asked to clarify whether the Veteran has an undiagnosed disease, or whether his symptoms of fatigue and joint pain are attributable to other disabilities with a known diagnosis. If fatigue and joint pain are attributable to a non-service-connected disability with a known diagnosis, the examiner is asked to opine to its etiology. 4. Sleep apnea The Veteran contends that his sleep apnea is secondary to his service-connected PTSD. At his hearing, for instance, he testified that he often found it hard to function during the daytime because he was tired after awakening from nightmares, in addition to tiredness caused by sleep apnea. He appears to be arguing that because he has difficulty falling and staying asleep due to PTSD, the symptoms of his sleep apnea, such as daytime somnolence, are aggravated. The RO afforded the Veteran with two separate VA examinations with respect to the etiology of his sleep apnea. In the first VA examination in August 2016, the VA examiner opined that the diagnosis of sleep apnea was less likely than no caused by environmental exposures in Southwest Asia but failed to address whether it was secondary to his PTSD. In the second VA examination in March 2019, the examiner stated that the etiology of sleep apnea was multifactorial, and that while there was an association between sleep apnea and PTSD, there was not a preponderance of the evidence showing that PTSD caused sleep apnea. The first opinion failed to address all raised theories of entitlement and is thus of limited probative value. Although the second opinion addressed whether sleep apnea was caused by PTSD, the opinion failed to address whether PTSD aggravated the symptoms of sleep apnea. An adequate medical opinion regarding secondary service connection must address causation and aggravation separately. See El Amin v. Shinseki, 26 Vet. App. 136, 140 (2013) (indicating that findings of "not due to," "not caused by," and "not related to" a service-connected disability are insufficient to address the question of aggravation under 38 C.F.R. § 3.310(b)). Moreover, the VA examiner failed to provide a sufficient rationale that adequately addressed the Veteran's lay statements on the possible relationship between his PTSD and his sleep apnea. Remand is thus warranted to obtain an addendum medical opinion. 5. TDIU It is the established VA policy that all veterans who are unable to secure and follow a substantially gainful occupation by reason of service-connected disability or disabilities shall be rated totally disabled. 38 C.F.R. § 4.16. In deciding whether TDIU may be awarded, an adjudicator must first evaluate the severity of the Veteran's service-connected disabilities. TDIU may be assigned where the schedular rating is less than total, when it is found that the disabled person is unable to secure or follow a substantially gainful occupation as a result of a single service-connected disability ratable at 60 percent or more, or as a result of two or more disabilities, provided at least one disability is ratable at 40 percent or more, and there is sufficient additional service-connected disability to bring the combined rating to 70 percent or more. 38 U.S.C. § 1155; 38 C.F.R. §§ 3.340, 3.341, 4.16(a). When the issue of entitlement to TDIU has been raised during the pendency of an increased rating claim, the Board must consider entitlement to TDIU throughout the entire period on appeal. Rice v. Shinseki, 22 Vet. App. 447, 453-55 (2009). Here, the issue of TDIU has been reasonably raised by the record during the period on appeal. For example, Dr. L. stated in his January 2018 private evaluation that the Veteran's PTSD symptoms affected his ability to cope with customer demands and run his self-owned business efficiently. Likewise, his VA treatment records indicate that he has angry outbursts directed towards employees and customers. As such, the issue of entitlement to TDIU has been reasonably raised by the record. However, the Board cannot yet reach the merits of the claim. At this juncture, the RO has not yet contacted the Veteran to furnish him with a VA Form 21-8940, Application for Increased Compensation Based on Unemployability, or furnished him with appropriate notice of how to substantiate a claim for TDIU. For this reason, remand is warranted for additional development. Moreover, because the resolution of the claims for service connection claims could potentially impact the resolution of the claim for TDIU, adjudication of the TDIU issue must be deferred until the other claims are resolved. Accordingly, the matters are REMANDED for the following action: 1. After obtaining proper authorization, obtain and associate with the claims file any outstanding VA treatment records, as well as any outstanding, relevant private treatment records. 2. After completing the development in step 1, obtain an addendum VA medical opinion regarding the nature and etiology of the Veteran's low back disability. The examiner must be provided with a copy of the entire claims file, including this remand, which the examiner must review in its entirety. If the examiner is unable to provide an addendum opinion without performing a physical examination of the Veteran, a new examination should be scheduled to assess the etiology, onset, nature, and severity of the Veteran's disability. After reviewing the claims file, the VA examiner is asked to opine as to whether it is at least as likely as not (approximately 50 percent or greater probability) that his low back disability was caused by or otherwise etiologically related to service, to include carrying heavy equipment during as part of an ordnance unit. The examiner is reminded that the Veteran's in-service back injury is conceded based on his combat service. A complete rationale is required for any opinion rendered by the examiner. All opinions should be based on examination findings, historical records, and medical principles. The examiner should fully articulate a sound reasoning for all conclusions made. In doing so, the examiner is reminded to consider all relevant evidence of record, including the Veteran's hearing testimony, lay statements, service treatment records, and post-service treatment records. 3. After completing the development in step 1, obtain an addendum VA medical opinion regarding the nature and etiology of the Veteran's heart condition. The examiner must be provided with a copy of the entire claims file, including this remand, which the examiner must review in its entirety. If the examiner is unable to provide an addendum opinion without performing a physical examination of the Veteran, a new examination should be scheduled to assess the etiology, onset, nature, and severity of the Veteran's disability. After reviewing the claims file, the VA examiner is asked to do the following: (a.) Opine as to whether it is at least as likely as not (approximately 50 percent or greater probability) that his heart condition was caused by or otherwise etiologically related to service, to include exposure to burn pits, immunizations, and Bromide pills during service in Southwest Asia. (b.) If the VA examiner ultimately opines that the Veteran's heart condition is at least as likely as not related to his service, the VA examiner must then opine as to whether his diabetes mellitus is (a) caused by, or (b) aggravated by his CAD. The examiner is reminded that causation and aggravation are distinct legal concepts that must be addressed separately. A complete rationale is required for any opinion rendered by the examiner. All opinions should be based on examination findings, historical records, and medical principles. The examiner should fully articulate a sound reasoning for all conclusions made. In doing so, the examiner is reminded to consider all relevant evidence of record, including the Veteran's hearing testimony, lay statements, service treatment records, and post-service treatment records. 4. After completing the development in step 1, arrange for the Veteran to undergo a VA examination on the nature and etiology of a disability characterized by chronic fatigue and joint pain. The examiner must be provided with a copy of the entire claims file, including this remand, which the examiner must review in its entirety. All necessary tests and studies should be performed. After reviewing the claims file in its entirety and examining the Veteran, the VA examiner is asked to do the following: (a.) Identify any diagnosable disabilities characterized by fatigue and muscle aches, to include chronic fatigue syndrome, that have been present during the period on appeal, even if such condition has since resolved. The examiner is also asked to clarify whether the Veteran's symptoms of fatigue and joint pain are manifestations of a service-connected disability or a separate, non-service-connected disability. (b.) For each condition identified, provide an opinion as to whether it is at least as likely as not (approximately 50 percent or greater probability) that it was caused by or otherwise etiologically related to service. (c.) If the Veteran has symptomatology that is not attributable to a known diagnosis, the examiner should opine as to whether it is at least as likely as not that there are symptoms due to any undiagnosed illness, or a medically unexplained chronic multi-symptom illness resulting from service in Southwest Asia during the Gulf War. If so, the examiner should comment on the severity of the symptomatology and report all signs and symptoms necessary for evaluating the illness under the rating criteria. A complete rationale is required for any opinion rendered by the examiner. All opinions should be based on examination findings, historical records, and medical principles. The examiner should fully articulate a sound reasoning for all conclusions made. In doing so, the examiner is reminded to consider all relevant evidence of record, including the Veteran's hearing testimony, lay statements, service treatment records, and post-service treatment records. 5. After completing the development in step 1, obtain an addendum VA medical opinion regarding the nature and etiology of the Veteran's sleep apnea. The examiner must be provided with a copy of the entire claims file, including this remand, which the examiner must review in its entirety. If the examiner is unable to provide an addendum opinion without performing a physical examination of the Veteran, a new examination should be scheduled to assess the etiology, onset, nature, and severity of the Veteran's disability. After reviewing the claims file, the VA examiner is asked to opine as to whether it is at least as likely as not (approximately 50 percent or greater probability) that sleep apnea is (a) caused by, or (b) aggravated by PTSD. The examiner is reminded that causation and aggravation are distinct legal concepts that must be addressed separately. A complete rationale is required for any opinion rendered by the examiner. All opinions should be based on examination findings, historical records, and medical principles. The examiner should fully articulate a sound reasoning for all conclusions made. In doing so, the examiner is reminded to consider all relevant evidence of record, including the Veteran's hearing testimony, lay statements, service treatment records, and post-service treatment records. 6. Request that the Veteran complete and return VA Form 21-8940, Application for Increased Compensation Based on Unemployability, and furnish him with appropriate notice of how to substantiate a claim for TDIU. M. Tenner Veterans Law Judge Board of Veterans' Appeals Attorney for the Board E. Rademacher, 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.