Apathy in multiple sclerosis: gender matters.

Apathy has been recognized as a frequent symptom in multiple sclerosis (MS) but uncertainty remains about its prevalence and clinical correlates. Therefore, the objective of this work was to assess the prevalence of apathy in patients with MS and to identify clinical and demographic correlates. A case-control study with 30 patients and 30 healthy controls matched for age, gender and education was performed. Apathy diagnosis was established using Robert et al.'s criteria. Additionally, apathy was assessed using the 10-item short version of the clinical-rated Apathy Evaluation Scale (AES-C-10). The Beck Depression Inventory (BDI), Modified Fatigue Impact Scale (MFIS), and Montreal Cognitive Assessment (MoCA) were used to evaluate depression, fatigue and cognitive impairment, respectively. Apathy prevalence in MS patients was 43.3%. Patients with MS had higher AES-C-10 scores than controls (13.9 vs. 12.0, p=0.015). Patients with apathy presented a higher proportion of males (53.8% vs. 11.8%, p=0.02), lower educational level (53.8% vs. 11.8% of patients with up to 9years of education), higher scores on cognitive dimension of MFIS (18.0 vs. 8.0, p=0.048) and BDI (13.0 vs. 7.0, p=0.035) and worse performance on MoCA (24.0 vs. 26.0, p=0.028). Gender was the only independent predictor of apathy, with men presenting a higher risk compared to women (OR: 9.62; 95%CI: 1.02-90.61; p=0.048). In conclusion, apathy is a common neuropsychiatric disorder in MS and it is probably underdiagnosed. Male patients seem to have an increased risk of apathy, and this finding may be related to the generally more unfavorable course of MS in men.