Introduction: Survivors of Intracerebral Hemorrhage (ICH) are at high risk for developing long-term incident cognitive decline and depression. However, owing largely to limited data on long-term post-ICH depression risk, the degree to which these two forms of post-hemorrhage clinical deterioration overlap is unknown.
Hypothesis: post-ICH depression is highly incident, and associated with long-term cognitive decline risk.
Methods: We followed longitudinally 695 ICH survivors with no prior history of depression. Exposures of interest included clinical information, known genetic risk factors for ICH / post-ICH dementia (APOE ε2/ε4), and imaging manifestations of cerebral small vessel disease on CT (CT-defined white matter disease [CT-WMD]). We captured outcomes (incident depression and dementia) during follow-up using validated scales administered via telephone every 6 months.
Results: A total of 271/695 ICH survivors (40%) developed new-onset mood disorder during a median follow-up time of 49.6 months (Figure). We estimated an incidence rate of 6.9% yearly (95% CI 5.5-8.8%) for post-ICH depression. Independent risk factors for post-ICH depression included lower educational achievements, APOE ε4, and moderate/severe CT-WMD (all p<0.05). Depression and dementia were co-diagnosed in 135/214 individuals (63%). Depression preceded post-ICH dementia in 108/135 cases (80%, 95% CI 71-88%, p = 0.002), with median anticipation of 17.5 months (IQR = 12.8-23.9).
Conclusions: we conducted the first-ever systematic evaluation of long-term post-ICH depression, which affects a large proportion of ICH survivors and shares risk factors (education, APOE genotype, CT-WMD severity) with risk for ICH recurrence and post-ICH dementia. Newly diagnosed depression often signals impending onset of dementia after ICH.