Determinants of disability using count-based approaches to ICF-based definition of neurological disability.

INTRODUCTION: The aim of this study was to explore the most relevant determinants of severe disability in a heterogeneous sample of patients with neurological conditions. OBJECTIVES: We used data from previous studies on patients with myasthenia gravis (MG), migraine, Parkinson's disease (PD), multiple sclerosis, traumatic brain injury (TBI), stroke and epilepsy (349 patients, aged 18-74 years; mean 48.0, SD 11.7). We calculated count-based extension indexes to address severe disability, and hierarchical logistic regression to assess the association between severe disability, sociodemographic and health status information. CONCLUSIONS: Results show that sociodemographic variables played a minor role, while health state information was a stronger determinant of severe disability. Compared to the reference value of TBI patients, those with MG, PD and epilepsy had higher odds to have severe difficulties undertaking daily activities despite the presence of environmental factors. Our results contrast with those of previous studies, mostly derived from general populations, showing the different impact of clinical and sociodemographic variables.