Impact of long-term systolic blood pressure on cognitive disorder risk: Across different age groups and antihypertensive medication timing

Abstract

Background

Elevated blood pressure (BP) is considered a risk factor for cognitive disorders. This study examined the continuous relationship between 2-year mean systolic BP (SBP) and incident cognitive disorders in a large, real-world primary care cohort.

Objective

To evaluate the associations of 2-year mean SBP with incident cognitive impairment in a ‘real-world’ clinical observational dataset.

Methods

We conducted a longitudinal analysis of electronic health records (EHR) from primary care patients aged 50 or older. Patients were included if they had ≥2 SBP measurements and no cognitive disorder diagnosis prior to or within 3 years of their first included SBP measurement. Exposure was the average SBP in the two years following the first measurement. We estimated associations between (continuous) average SBP and incident cognitive impairment using a Cox model. Records from 160,052 patients were included in the analysis.

Results

In our study, SBP ≥ 140 mmHg is not associated with a statistically significant difference in cognitive disorder risk compared to lower SBP (<120 and 120–140 mmHg). In the ages 60–69 group, SBP 135 mmHg is the lowest SBP at which a significantly decreased risk for cognitive disorders was observed (HR, 0.84; 95% CI, 0.82–0.89; p < 0.05). Among unmedicated individuals, 136 mmHg SBP was the lowest SBP at which a statistically significant association with decreased cognitive disorder risk was observed (HR, 0.92; 95% CI, 0.87–1.00; p < 0.05).

Conclusions

The association between SBP and cognitive disorder risk varies by age and BP medication use. This highlights the need for individualized BP targets to mitigate cognitive impairment.