Prevalence of mild cognitive impairment in patients with hypertension: a systematic review and meta-analysis

Mild cognitive impairment (MCI) is common in patients with hypertension. Prevalence estimates of MCI in hypertensive patients are needed to guide both public health and clinical decision making. A literature search was conducted in four databases, including PubMed, Embase, Cochrane Library, and Web of Science, from their inception to February 2021. The methodological quality assessment used the risk of bias tool. The pooled prevalence of MCI in hypertensive patients was determined by a random-effects model. Heterogeneity was explored using sensitivity analysis, subgroup analysis, and random effects meta-regression. Of 2314 references, 11 studies (47,179 participants) were included in the meta-analysis. The overall pooled prevalence of MCI in patients with hypertension was 30% (95% CI, 25–35), with significant heterogeneity present (I2 = 99.3%, p < 0.001). In subgroup analyses, Asian and European samples had a prevalence of 26% (95% CI, 20–31) and 40% (95% CI, 14–66), respectively; cross-sectional and cohort studies had a prevalence of 28% (95% CI, 24–32) and 38% (95% CI, −5–81); age older than 60 years had a prevalence of 28% (95% CI, 23–33); community-based and clinic-based samples had a prevalence of 17% (95% CI, 15–19) and 42% (95% CI, 23–62); and MCI diagnosis using the MoCA, NIA-AA, MMSE, and Peterson criteria had a prevalence of 64% (95% CI, 59–68), 18% (95% CI, 16–19), 19% (95% CI, 15–23), and 13% (95% CI, 9–17). Meta-regression analysis showed that different MCI diagnostic criteria could be the source of heterogeneity in the pooled results. MCI is common in patients with hypertension, with an overall prevalence of 30%. Earlier cognitive screening and management in hypertensive patients should be advocated.