Restrictive Lung Disease VA Rating: FVC Tiers & 38 CFR 4.97

Restrictive respiratory disorders occur when physical chest wall restrictions, diaphragmatic impairment, or pleural scarring prevent the lungs from fully expanding. Diagnostic Codes 6840 through 6845 evaluate conditions such as diaphragmatic paralysis (DC 6840), spinal chest deformities like kyphoscoliosis or pectus excavatum (DC 6844), and chronic pleural effusion or pleural fibrosis (DC 6845). Unlike obstructive conditions that trap air, restrictive disorders are defined physiologically by reduced total lung capacity and decreased Forced Vital Capacity.

The rating schedule for restrictive lung disease in 38 CFR 4.97 establishes four objective evaluation tiers based on post-bronchodilator spirometry measurements: 100% applies when FVC is less than 50% of predicted, or when the veteran requires continuous outpatient oxygen therapy; 60% applies when FVC is 50% to 64% of predicted; 30% applies when FVC is 65% to 74% of predicted; and 10% applies when FVC is 75% to 80% of predicted. FVC measurements of 80% or greater are non-compensable.

During a VA C&P examination, the examiner interprets spirometry results to differentiate restrictive from obstructive impairment. Obstructive conditions like asthma or COPD produce a reduced FEV-1/FVC ratio (typically below 70%). In contrast, pure restrictive lung disease produces a normal or elevated FEV-1/FVC ratio alongside a proportionally reduced FVC and total lung capacity (TLC). When spirometry indicates restriction, full plethysmography is often required to confirm reduced lung volumes.

Restrictive lung disease frequently develops secondary to severe service-connected musculoskeletal trauma or degenerative spinal pathology under 38 CFR 3.310. Severe thoracic kyphoscoliosis, ankylosing spondylitis (DC 5240), multiple rib fractures with flail chest (DC 6843), or surgical chest wall resections compress the thoracic cavity, mechanically restricting lung expansion. Veterans with service-connected spine or thoracic trauma should seek pulmonary evaluation if shortness of breath develops.

Under 38 CFR 4.96(b), pulmonary function testing submitted for VA rating purposes must include both pre-bronchodilator and post-bronchodilator measurements, with the post-bronchodilator results governing evaluation unless medically contraindicated. For veterans claiming a 100% evaluation based on oxygen therapy, medical records must establish that outpatient oxygen has been continuously prescribed by a licensed physician and is medically necessary for chronic hypoxemia.