PULMONARY-FUNCTION IN SPINAL MUSCULAR-ATROPHY

We present the first prospective study on pulmonary function in spinal muscular atrophy patients. Seventy-seven spinal muscular atrophy pati ents, ages 5 to 18 years, from three centers, were studied with regard to forced vital capacity, using height as a predictor. Patients were categorized into four motor function categories. The highest-functioni ng group had normal or near-normal values, and those who sat with supp ort had the lowest values. Those with intermediate function had interm ediate values. Forced vital capacity was studied longitudinally in 40 spinal muscular atrophy patients for 1.1 to 4.4 years. Eighty-eight pe rcent of patients grew in height, but only 35% showed an increase in h eight-adjusted forced vital capacity percent. In those patients with t he least function, 100% lost height-adjusted forced vital capacity ove r time. In those patients with the highest function, 57% lost height-a djusted forced vital capacity. In addition, the basic forced vital cap acity, not correlated to height, decreased in 43% of cases. These pulm onary function alterations appear to be important determinants for fun ction and survival in spinal muscular atrophy patients.