Depression and Risk of Stroke—Reply

In Reply: Mr Dong raised the possibility of reverse causality. We conducted a stratified analysis by presence or absence of baseline stroke, and the results were similar. A further analysis by follow-up time showed similar results in studies with 10 years or less of follow-up (HR 1.43; 95% CI, 1.23-1.66) and in those with greater than 10 years of follow-up (HR, 1.49; 95% CI, 1.26-1.76) (eTable 3; see correction).

Dong noted that depression significantly increased stroke risk in patients with prior cardiac disease but not in persons free of it in 2 cohort studies. However, this was not observed in another study.¹ Further studies are needed to determine whether cardiovascular disease or other comorbidities modify the association between depression and stroke. The population attributable risk may be overestimated if the publication bias was corrected, but it could not be calculated based on hypothetical studies that were imputed using the trim-and-fill method for publication bias correction.