Does hypercholesterolemia worsen cognitive decline in arterial hypertension? Insights from clinical and experimental studies.

BACKGROUND: Arterial hypertension has been linked to cognitive decline, potentially through cerebrovascular alterations and associations with Alzheimer's disease. A positive correlation between elevated serum cholesterol levels and cognitive impairment has been observed. However, the impact of hypercholesterolemia on cognitive decline in both hypertensive rats and patients remains unclear. This study aimed to test the hypothesis that hypercholesterolemia exacerbates cognitive decline in hypertensive rats and human patients. METHODS: Spontaneously hypertensive rats (SHR) with diet-induced hypercholesterolemia underwent behavioral testing to assess recognition, spatial, and working memory. In patients with stage 2 hypertension, cognitive function was assessed using the Mini Mental State Examination (MMSE) and the Montreal Cognitive Assessment (MoCA) instruments. RESULTS: In SHRs, hypercholesterolemia did not alter cognitive performance. Treatment of SHR with amlodipine or captopril decreased arterial pressure; however, this reduction did not improve cognition performance. The MMSE and MoCA, respectively, revealed cognitive impairment in 87.1 and 97.6% of the hypertensive patients. Nevertheless, no significant differences were found in the mean scores between hypertensive patients with and without hypercholesterolemia. No significant correlation was observed between cognitive scores and the use of antihypertensive or lipid-lowering agents. CONCLUSION: These observations provide evidence that hypercholesterolemia does not exacerbate cognitive impairment in hypertension. Furthermore, our current findings support the hypothesis that antihypertensive treatment, in the absence of strict blood pressure control, may be insufficient to prevent hypertension-related cognitive decline.