Clinical outcomes of antihypertensive medication use in people with dementia: a systematic review and meta-analysis.

Nearly half of patients with dementia have comorbid hypertension. However, evidence on the clinical outcomes of antihypertensive medications (AHMs) in these patients remains inconsistent. This review synthesises evidence on cognitive, functional and behavioural outcomes, cardiovascular events, hospitalisation, mortality and adverse drug events related to the use of AHMs in patients with dementia. The review was registered with PROSPERO (CRD42024619054) and is reported following the PRISMA guidelines. We searched MEDLINE, Embase, CENTRAL, PsycINFO, CINAHL and Google Scholar. Random-effects meta-analyses were conducted. We included 36 studies (10 randomised controlled trials (RCTs) and 26 observational follow-up studies) involving 276,793 patients. Meta-analysis showed a small but statistically significant cognitive benefit with AHM use versus non-use in observational studies (standardised mean difference (SMD) 0.23; 95% CI 0.20 to 0.27; p < 0.001), but not in RCTs (SMD - 0.01; 95% CI - 0.16 to 0.14; p = 0.92). Associations with functional outcomes (SMD 0.45; 95% CI - 0.52 to 1.42; p = 0.36), behavioural outcomes (SMD - 0.11; 95% CI - 0.79 to 0.57; p = 0.75) and mortality (hazard ratio 1.32; 95% CI 0.41 to 4.27; p = 0.64) were not significant. Regimens containing renin-angiotensin system blockers (RASBs) showed less cognitive decline compared to other AHMs. Data on the cardiovascular outcomes of AHM use were limited. In summary, AHM use was associated with slower cognitive decline in observational studies (not in RCTs), but no significant relationships with functional, behavioural, or mortality outcomes. The slowed cognitive decline was most pronounced with RASBs. More research, especially RCTs, examining the clinical benefits of AHM use in people with dementia is required.