Long-Term Survival in Werdnig–Hoffmann Disease

Abstract

To report long-term survival of spinal muscular atrophy type 1 (SMA 1) and consequences on speech and ventilator dependence as a function of mode of ventilator use. A retrospective chart review of 106 consecutively referred SMA 1 patients, the 92 most severe of which were considered in three groups: untreated (group 1), tracheostomy managed (group 2), and noninvasively managed (group 3). The untreated patients died at 9.6 +/- 4.0 mos of age. The mean age of the 22 patients referred with tracheostomy tubes (group 2) was 70.5 +/- 43.3 mos (range 2-159 mos); five died at 66.2 +/- 114.2 mos (range 8-270 mos) of age. Six had comprehendible speech at the time of tracheotomy and retained some ability to vocalize afterward. None of the 21 patients who had not developed the ability to speak did so after tracheotomy. Twenty-five of the 27 total lost all autonomous breathing ability immediately, and definitively, after tracheotomy. The 47 patients who used noninvasive mechanical ventilation (NIV) (group 3) were extubated to it during episodes of acute respiratory failure. Thirty-nine of these were 65.2 +/- 45.8 mos (range 11-153 mos) of age, and eight died at 60.9 +/- 26.1 mos (range 36-111 mos) of age. There was no significant difference in longevity with or without tracheostomy, but the NIV patients had significantly fewer (P = 0.04) hospitalizations per year after age 5; 39 of the 47 could communicate verbally, and only nine were continuously dependent on NIV. NIV and tracheostomy can both prolong survival for SMA 1 patients, but the latter results in continuous ventilator dependence and speech does not develop.