Prevalence and predictors of depression in Iranian patients with multiple sclerosis: a population-based study.

Depression is a frequent symptom in multiple sclerosis (MS) which has a negative impact on quality of life and cognitive status. The purpose of this study was to determine the prevalence and associated factors of depression, and status of antidepressant use in Iranian MS patients. One-hundred and sixty patients with definite MS were included. Demographic and clinical characteristics were recorded. Fatigue and depression were evaluated using the fatigue severity scale and Beck depression inventory-II. Cognitive performance and disability were examined by mini-mental status examination and expanded disability status scale. Multiple logistic regressions were used to determine the associated factors of depression and antidepressant use. The prevalence of depression and severe depression was 59.4 and 18.1 %, respectively. However, only 21.1 % of patients were on antidepressant treatment, while the prevalence of unrecognized/untreated depression was found to be as high as 44.1 %. Multivariable analysis showed that fatigue (P < 0.0001, OR = 5.98, 95 % CI = 2.9-12.3) and older age (P = 0.027, OR = 2.24, 95 % CI = 1.09-4.6) were associated with depression in MS patient. A significant association was found between fatigue and antidepressant use (P = 0.001, OR = 6.81, 95 % CI = 2.26-20.48). Our findings demonstrate that depression is significantly associated with fatigue and older age, regardless of other factors. Moreover, despite the high prevalence of depression in MS, most patients do not receive adequate treatment.