Cognitive impairment associated with increased mortality rate in patients with heart failure: A systematic review and meta-analysis

BACKGROUND: Recent systematic review and meta-analysis showed that the prevalence of cognitive impairment was significantly increased in patients with heart failure (HF) when compared to the general population. However, the effect of cognitive impairment on cardiovascular outcome in this population is still unclear. We performed a systematic review and meta-analysis to assess whether cognitive impairment associated with worse outcome in patients with HF. METHODS: We comprehensively searched the databases of MEDLINE and EMBASE from inception to October 2018. Included studies were published cohort (prospective or retrospective) or randomized control trials that evaluate the effect of cognitive impairment mortality in HF patients. Data from each study were combined using the random-effects, generic inverse variance method of DerSimonian and Laird to calculate pooled hazard ratios (HR) and 95% confidence intervals (CI). RESULTS: Eight studies were included in the analysis involving 3318 participants (951 participants had cognitive impairment). In a random-effects model, our analysis demonstrated that cognitive impairment significantly increased the risk of mortality in HF patients (pooled HR = 1.64, 95% CI = 1.42–1.88, I(2) = 0.0%, p < 0.001). CONCLUSION: Our systematic review and meta-analysis showed that the presence of cognitive impairment is strongly associated with an increased mortality risk in the HF population. Further research is needed to explore the pathophysiology of this association.