Which Ambulatory Blood Pressure Parameters Are Related to Cognitive Impairment and Dementia in Hypertensive Patients?

Abstract

Objective: Ambulatory blood pressure monitoring (ABPM) parameters are more accurately linked to target organ damage than office or home blood pressure values. Few studies focus on the relationship between ABPM parameters and cognitive aging. We aimed to investigate the relationship between ABPM parameters and prevalence of cognitive impairment and dementia among hypertensive patients. Design and method: In the present paper, we included 294 consecutive hypertensive patients admitted to a Cardiovascular Rehabilitation Clinic aged between 50–91years (mean age: 68.6 ± 8.8 years; 50.3% female; 49.7% male). After routine clinical assessment all participants had an ABPM recording (on antihypertensive medical treatment), completed the Montreal Cognitive Assessment (MoCA) test used for the detection of cognitive impairment, and the Mini Mental State Examination (MMSE) test for detection of dementia. We divided patients in two groups acording to cognitive status based on these cutoff values: 26 points for MOCA score, respectively 24 points for MMSE score – and compared ABPM parameters of the two groups. Statistical analysis was performed with the IBM SPSS v.20 program. Results: In patients with cognitive impairment (MOCA <26) we found significantly lower mean diastolic (69.9 vs. 72.4 mmHg, p = 0.023), daytime diastolic (72.0 vs. 75.1 mmHg, p = 0.012), nighttime diastolic (64.5 vs. 66.9 mmHg, p = 0.039), and higher pulse pressure values (average pulse pressure 61.5 vs. 55.5 mmHg, p = 0.002, daytime pulse pressure 61.7 vs. 56.6 mmHg, p = 0.003, nighttime pulse pressure (59.8 vs. 55.1 mmHg, p = 0.004). In patients with dementia (MMSE<24) we found significant differences between nighttime systolic values (129.7 vs. 124.5 mmHg, p = 0.04), average pulse pressure (63.5 vs. 58.9 mmHg, p = 0.038), and nighttime pulse pressure (63.5 vs. 57.4 mmHg, p = 0.003), values compared to patients with normal cognitive function. Conclusions: The presence of cognitive impairment was related to lower diastolic values, and higher pulse pressure values, while dementia was associated with higher nighttime systolic values in the studied patient population. Lowering too much diastolic blood pressure leading to higher pulse pressure and insufficient control of systolic blood pressure over night could have deleterious effect on neurocognitive abilities of treated hypertensive patients.