The cost-effectiveness of early noninvasive ventilation for ALS patients

Using a Markov decision analytic model we calculated the benefit in health-state utility that NIPPV initiated at ALS diagnosis must achieve to be cost-effective. The primary outcome was the percent utility gained through NIPPV in relation to two common willingness-to-pay thresholds: $50,000 and $100,000 per quality-adjusted life year (QALY).Our results indicate that if NIPPV begun at the time of diagnosis improves ALS patient HRQL as little as 13.5%, it would be a cost-effective treatment. Tolerance of NIPPV (assuming a 20% improvement in HRQL) would only need to exceed 18% in our model for treatment to remain cost-effective using a conservative willingness-to-pay threshold of $50,000 per QALY.If early use of NIPPV in ALS patients is shown to improve HRQL in future studies, it is likely to be a cost-effective treatment. Clinical trials of NIPPV begun at the time of ALS diagnosis are therefore warranted from a cost-effectiveness standpoint.Respiratory failure is the most common cause of ALS patient death[1]. Prior to respiratory failure, respiratory muscle weakness can be measured by standard pulmonary function tests including forced vital capacity (FVC)[2]. Treatment of ALS patients with noninvasive positive pressure ventilation (NIPPV) when FVC is less than 50% appears to improve ALS patient survival[3,4] and quality of life [5-7]. Improved survival of ALS patients with NIPPV may be explained by a slower rate of pulmonary function decline[4,5].NIPPV initiated early in the ALS disease course may off-load respiratory muscle work and thereby attenuate the progressive decrease in pulmonary compliance seen in ALS[8]. This treatment may also improve quality of life as ALS patients early in their course may experience non-specific symptoms of fatigue and lethargy, related to subtle respiratory muscle weakness, which goes unrecognized or is attributed to impaired mobility[2]. Whether initiation of NIPPV at diagnosis, when FVC is typically reduced but greater than 50%, slow