Measures Associated With Early, Late, and Persistent Clinically Significant Symptoms of Depression 1 Year After Stroke in the AFFINITY Trial

Abstract

Objective:To determine the sociodemographic and clinical factors associated with early, late and persistent clinically significant symptoms of depression during the first year after a stroke.Methods:Cohort study of 1221 men and women recruited within two weeks of stroke onset in Australia, New Zealand and Vietnam. The NIH Stroke Scale (NIHSS) was used to assess the severity of the stroke. Other study measures included age, sex, marital status, living arrangements, function before the stroke, depression before the stroke, modified Rankin Scale (mRS), and treatment with fluoxetine or placebo for 26 weeks. Clinically significant symptoms of depression during the 52 weeks after baseline was the outcome of interest, and its presence was defined by a total PHQ-9 score of 9 or higher at weeks 4, 12, 26 or 52, a clinician diagnosis of depression between assessments, or by pharmacological or psychological treatment of depression during follow up. Participants were classified as not depressed, or as early (initial 12 weeks), late (12 to 52 weeks) or persistent depression (before and after 12 weeks). We used multinomial logistic regression to assess depression risk, with all listed measures entered simultaneously into the model.Results:The mean age of participants was 63.8 (SD=12.3) years and 775 (63.5%) were male. At baseline, 48 (3.9%) participants had previous treated depression, and 228 (18.7%) had clinically significant symptoms of depression (PHQ-9 ≥ 9). 734 (63.3%) participants showed no evidence of depression in the year following the stroke, 208 (17.9%) had early, 86 (7.4%) late, and 131 (11.3%) persistent depression. Increased stroke severity, as measured by doubling of NIHSS scores, was associated with an increased risk of early (Risk Ratio [RR]=2.08, 95%CI=1.65-2.62), late (RR=1.53, 95%CI=1.14-2.06) and persistent clinically significant symptoms of depression (RR=2.50, 95%CI=1.89-3.32). Similar findings were apparent for the mRS, a measure of functional disability. Past depression was associated with increased risk of persistent clinically significant symptoms of depression (RR=6.28, 95%CI=2.88-13.71), as was being married or partnered (RR=3.94, 95%CI=2.42-6.41). The risk of clinically significant symptoms of depression was higher in Australia and New Zealand than in Vietnam.Conclusion:The severity of neurological and functional deficits increases the risk of post-stroke clinically significant symptoms of depression early and persistently. Depression before stroke, personal relationships and cultural context contribute to mediate depression risk. Interventions that minimise the severity of neurological and functional deficits should decrease the risk of post-stroke clinically significant symptoms of depression.