A prospective study on the prevalence and risk factors of poststroke depression

Poststroke depression (PSD) is common. Early detection of depressive symptoms and identification of patients at risk for PSD are important as PSD negatively affects stroke outcome and costs of medical care. Therefore, the aim of this study was to determine incidence and risk factors for PSD at 3 months after stroke.

We conducted a prospective, longitudinal epidemiological study aiming to determine incidence and risk factors for PSD at 1, 3, 6, 12 and 18 months poststroke. The present data analysis covers the convalescent phase of 3 months poststroke. Participants in this study were inpatients, admitted to a stroke unit with first or recurrent stroke. Demographic data and vascular risk factors were collected and patients were evaluated at baseline and 3 months poststroke for functional and cognitive deficits, stroke characteristics, stroke severity and stroke outcome. Signs and symptoms of depression were quantified by means of the Cornell Scale for Depression (CSD) and Montgomery and Åsberg Depression Rating Scale (MADRS). Significantly associated variables from univariate analysis were analyzed by using multiple linear and logistic regression methods.

Data analysis was performed in 135 patients who completed follow-up assessments at 3 months poststroke. Depression (CSD score ≥8) was diagnosed in 28.1% of the patients. Patients with PSD were significantly more dependent with regard to activities of daily living (ADL) and displayed more severe physical and cognitive impairment than patients without PSD. A higher prevalence of speech and language dysfunction and apraxia were observed in patients with PSD (36.8 and 34.3%, respectively) compared to non-depressed stroke patients (19.6 and 12.4%; p = 0.036 and p = 0.004, respectively). Applying multiple linear regressions, cognitive impairment and reduced mobility as part of the Stroke Impact Scale were independently associated with PSD, as scored using CSD and MADRS (r(2) = 0.269 and r(2) = 0.474, respectively).

The risk of developing PSD is increased in patients with more functional and cognitive impairment, greater dependency with regard to ADL functions and with occurrence of speech and language dysfunctions and apraxia. Multiple regression models indicated that the most determining features for depression risk in the convalescent phase after stroke include reduced mobility and cognitive impairment. Further studies on risk factors for PSD are essential, given its negative impact on rehabilitation and quality of life. Identification of risk factors for PSD may allow more efficacious preventive measures and early implementation of adequate antidepressive treatment.