['To assess the effect of neurobehavioral dysfunction on amyotrophic lateral sclerosis (ALS) survival and on the use of life-prolonging therapies in a population-based setting.', 'Of the 132 patients diagnosed with ALS in the province of Torino, Italy, between January 1, 2007, and June 30, 2008, 128 participated in the study. Neurobehavioral dysfunction was assessed with the Frontal Systems Behavior Scale (FrSBe), using the Family Rating forms, administered within 4 months from diagnosis.', 'The 128 patients included 71 men and 57 women, with a mean age at onset of 64.7 (SD 11) years. Forty-one patients (32.0%) had a neurobehavioral dysfunction and 9 (7.0%) an isolated dysexecutive behavior. Enteral nutrition (EN) and noninvasive ventilation (NIV) were performed with similar frequencies in patients with and without neurobehavioral dysfunction. Patients with neurobehavioral dysfunction had a significantly shorter survival than those with a normal FrSBe score (median survival, 3.3 vs 4.3 years; p = 0.02). Patients with isolated dysexecutive behavior had a shorter survival than those without neurobehavioral dysfunction (median survival, 2.5 vs 4.5 years; p = 0.03). Patients with neurobehavioral dysfunction had a shorter survival after EN and NIV, while patients with isolated dysexecutive behavior had a shorter survival after NIV but not after EN. The negative effect of comorbid neurobehavioral dysfunction and of isolated dysexecutive behavior on survival persisted under the Cox multivariate model.'] Does neurobehavioral dysfunction in ALS have a negative effect on outcome and use of PEG and NIV?