Long-Term Changes in Poststroke Depressive Symptoms: Effects of Functional Disability and Social Support.

Abstract

Long-term changes in specific depressive symptoms have rarely been studied in stroke patients. Such changes and the effects of social support and functional disability on specific symptoms after a long-term follow-up period (LTP) were investigated. The Montgomery-Åsberg Depression Rating Scale (MADRS), ENRICHD Social Support Instrument, and modified Rankin Scale (mRS) for functional disability were administered at baseline, a 6-month follow-up, and an LTP (35-83 months). Effects of social support and poor functional outcome (mRS score of 3 to 6) on the 10 single items included on the MADRS were identified. Among 222 patients, mRS score, total MADRS score, and all single-item scores except "concentration difficulties," "inability to feel," and "suicidal thoughts" improved at the 6-month follow-up. From the 6-month follow-up to the LTP, the total MADRS score and half of the single-item scores worsened, although the functional outcome measure continued to improve. In multivariable linear regression tests, low social support was associated with "reduced sleep" (standardized β=0.20; 95% CI=0.06 to 0.34, p=0.005) and "pessimistic thoughts" (standardized β=0.16, 95% CI=0.03 to 0.30, p=0.019), and poor functional outcome was associated with all specific symptoms (standardized β values=0.18-0.43, all p<0.02) except "reduced sleep." Although total MADRS and single-item scores improved in parallel with improvements in functional outcome at the 6-month follow-up, these scores worsened afterward. The lack of social support and presence of functional disability were both associated with total MADRS scores. However, specific symptoms were differentially affected, suggesting that tailored strategies should be applied to manage depression in stroke patients.