Cognitive functioning in outpatients diagnosed with schizophrenia, with and without comorbid alcohol abuse

Objectives As the available studies suggest, inconsistently, that alcoholabuse may be associated with greater cognitive impairment in schizophrenia patients, we compared cognitive functioning among matched schizophrenia patients with and without comorbid alcohol abuse, and matched healthy controls. Methods We applied the Milan Overall Dementia Assessment (MODA) cognitive test battery to compare cognitive functioning in patients with schizophrenia meeting DSM-IV criteria with (n = 17) or without (n = 40) lifetime alcohol abuse, verified with the Michigan Alcohol Screening Test (MAST), and patients versus healthy controls (n = 21) matched for age, sex, education and psychosis ratings. Results Cognitive performance was greatly impaired in both patient-groups compared to healthy controls, but only 6.2% more among patients with than without a history of alcohol-abuse. MODA and MAST scores were highly and inversely correlated. Conclusions Cognitive functioning in schizophrenia patients was substantially lower than in healthy subjects, as expected, but only slightly more impaired with a lifetime history of alcohol abuse