Antihypertensive medication classes and the risk of dementia over a decade of follow-up

Comparative effects of angiotensin II stimulating and inhibiting antihypertensives on dementia risk: a systematic review and meta-analysis

Studies comparing the effects of Angiotensin II (Ang-II) stimulating and inhibiting antihypertensive medications (AHMs) on dementia risk have reported inconsistent findings. Based on the PRISMA guidelines, this study was performed to pool these findings. We searched PubMed, Scopus, Embase Ovid, PsycINFO, and CINAHL from inception to 22 May 2024 for randomised controlled trials (RCTs) and observational studies that compared the use of Ang-II stimulating (thiazides, Ang-II receptor blockers, and dihydropyridine calcium channel blockers) and inhibiting AHMs (β-blockers, angiotensin-converting enzyme inhibitors, and non-dihydropyridine calcium channel blockers) and the subsequent risk of developing dementia. Two reviewers independently performed study selection, data extraction, and quality assessment. Random effects meta-analysis models were used to calculate hazard ratios (HRs) or risk ratios (RRs) with their confidence intervals (CIs). All-cause dementia was the primary outcome. Alzheimer's disease (AD), vascular dementia (VD), and mild cognitive impairment (MCI) were secondary outcomes. We included 18 studies with 1,883,283 participants. Observational studies showed that the use of Ang-II stimulating AHMs reduced the risk of all-cause dementia by 13% (HR = 0.87; 95% CI = 0.82-0.93) compared with Ang-II inhibiting AHMs. The risk of AD was reduced by 12% (HR = 0.88; 95% CI = 0.86-0.90), VD by 19% (HR = 0.81; 95% CI = 0.72-0.91), and MCI by 24% (HR = 0.76; 95% CI = 0.68-0.85) in these studies. A meta-analysis of four RCTs revealed a non-significant 8% reduction in dementia risk with Ang-II stimulating AHMs versus control (RR = 0.92; 95% CI = 0.79-1.08). Observational evidence suggests that Ang-II stimulating AHMs may offer neuroprotective benefits relative to Ang-II inhibiting AHMs.

Antihypertensive medication classes and risk of incident dementia in primary care patients: a longitudinal cohort study in the Netherlands

Background

Hypertension is a modifiable risk factor for dementia affecting over 70% of individuals older than 60. Lowering dementia risk through preferential treatment with antihypertensive medication (AHM) classes that are otherwise equivalent in indication could offer a cost-effective, safe, and accessible approach to reducing dementia incidence globally. Certain AHM-classes have been associated with lower dementia risk, potentially attributable to angiotensin-II-receptor (Ang-II) stimulating properties. Previous study results have been inconclusive, possibly due to heterogeneous methodology and limited power. We aimed to comprehensively investigate associations between AHM (sub-)classes and dementia risk using large-scale continuous, real-world prescription and outcome data from primary care.

Methods

We used data from three Dutch General Practice Registration Networks. Primary endpoints were clinical diagnosis of incident all-cause dementia and mortality. Using Cox regression analysis with time-dependent covariates, we compared the use of angiotensin-converting enzyme inhibitors (ACEi) to angiotensin receptor blockers (ARBs), beta blockers, calcium channel blockers (CCBs), and diuretics; and Ang-II-stimulating- to Ang-II-inhibiting AHM.

Findings

Of 133,355 AHM-using participants, 5877 (4.4%) developed dementia, and 14,079 (10.6%) died during a median follow-up of 7.6 [interquartile range = 4.1-11.0] years. Compared to ACEi, ARBs [HR = 0.86 (95% CI = 0.80-0.92)], beta blockers [HR = 0.81 (95% CI = 0.75-0.87)], CCBs [HR = 0.77 (95% CI = 0.71-0.84)], and diuretics [HR = 0.65 (95% CI = 0.61-0.70)] were associated with significantly lower dementia risks. Regarding competing risk of death, beta blockers [HR = 1.21 (95% CI = 1.15-1.27)] and diuretics [HR = 1.69 (95% CI = 1.60-1.78)] were associated with higher, CCBs with similar, and ARBs with lower [HR = 0.83 (95% CI = 0.80-0.87)] mortality risk. Dementia [HR = 0.88 (95% CI = 0.82-0.95)] and mortality risk [HR = 0.86 (95% CI = 0.82-0.91)] were lower for Ang-II-stimulating versus Ang-II-inhibiting AHM. There were no interactions with sex, diabetes, cardiovascular disease, and number of AHM used.

Interpretation

Among patients receiving AHM, ARBs, CCBs, and Ang-II-stimulating AHM were associated with lower dementia risk, without excess mortality explaining these results. Extensive subgroup and sensitivity analyses suggested that confounding by indication did not importantly influence our findings. Dementia risk may be influenced by AHM-classes' angiotensin-II-receptor stimulating properties. An RCT comparing BP treatment with different AHM classes with dementia as outcome is warranted.

Funding

Netherlands Organisation for Health, Research and Development (ZonMw); Stoffels-Hornstra Foundation.

Vascular dementia: From pathobiology to emerging perspectives

Vascular dementia (VaD) is the second most common type of dementia. VaD is synonymous with ageing, and its symptoms place a significant burden on the health and wellbeing of older people. Despite the identification of a substantial number of risk factors for VaD, the pathological mechanisms underpinning this disease remain to be fully elucidated. Consequently, a biogerontological imperative exists to highlight the modifiable lifestyle factors which can mitigate against the risk of developing VaD. This review will critically examine some of the factors which have been revealed to modulate VaD risk. The survey commences by providing an overview of the putative mechanisms which are associated with the pathobiology of VaD. Next, the factors which influence the risk of developing VaD are examined. Finally, emerging treatment avenues including epigenetics, the gut microbiome, and pro-longevity pharmaceuticals are discussed. By drawing this key evidence together, it is our hope that it can be used to inform future experimental investigations in this field.

Angiotensin Receptor Blockers and Cognition: a Scoping Review

PURPOSE OF REVIEW

To provide an overview of the association between angiotensin II receptor blocker (ARB) use and cognitive outcomes.

RECENT FINDINGS

ARBs have previously shown greater neuroprotection compared to other anti-hypertensive classes. The benefits are primarily attributed to the ARB's effect on modulating the renin-angiotensin system via inhibiting the Ang II/AT1R pathway and activating the Ang II/AT2R, Ang IV/AT4R, and Ang-(1-7)/MasR pathways. These interactions are associated with pleiotropic neurocognitive benefits, including reduced β-amyloid accumulation and abnormal hyperphosphorylation of tau, ameliorated brain hypo-fusion, reduced neuroinflammation and synaptic dysfunction, better neurotoxin clearing, and blood-brain barrier function restoration. While ACEis also inhibit AT1R, they simultaneously lower Ang II and block the Ang II/AT2R and Ang IV/AT4R pathways that counterbalance the potential benefits. ARBs may be considered an adjunctive approach for neuroprotection. This preliminary evidence, coupled with their underlying mechanistic pathways, emphasizes the need for future long-term randomized trials to yield more definitive results.