Elevated systolic blood pressure is associated with episodic memory decline in healthy aging

Abstract

AbstractBackgroundElevated blood pressure (BP) is associated with poorer cognitive performance in ageing but not in the very old (Obisesan et al., 2008). Likewise, hypertension causes vascular dysregulation and eventually decreased blood flow in several regions including the hippocampus (Glodzik et al., 2019) and is associated with faster cognitive decline in Mild Cognitive Impairment (MCI) patients (Goldstein et al., 2013). However, the association between BP and memory performance remains controversial with studies finding different results (reviewed in Forte et al., 2020). Longitudinal examinations are also non‐conclusive. One study showed association between poorer memory performance and higher systolic BP (SBP) at baseline, but not at follow‐up examination (Waldstein et al., 2005); and a previous one found that elevated SBP predicted greater number of errors in a memory task over time (Glynn eta l., 1999). We aim to explore the association between baseline SBP and memory change in healthy aging.Method77 healthy elders (age range 65‐78) were selected from the Institute of Aging (Barcelona). Rey Auditory verbal learning Task (RAVLT) was administered at baseline and follow‐up examination (mean interval period was 4.15 years, SD=0.44). Partial correlations were conducted between SBP and percent of change in RAVLT total learning and delayed scores. Control variables included age at baseline, interval period between assessments, medication for hypertension (medicated versus unmedicated) and years of education. All individuals presented normal global cognitive function (Mini Mental state Examination ≥ 25) and RAVLT delayed scores ≥ 5, to exclude possible MCI cases.ResultA significant negative correlation was found between SBP at baseline and percent of change in delayed episodic memory (r=‐0.338, p=0.003, Bonferroni corrected p=0.021). Interestingly, no significant associations were found between SBP and cross‐sectional measures of delayed RAVLT.ConclusionElevated SBP was associated with increased decline in delayed verbal memory in healthy aging. Delayed episodic memory is a key factor for characterizing subjects at risk of dementia and therefore, targeting measures to maintain optimal levels of BP should be a priority for primary care medicine.