Poorly controlled blood pressure is a risk factor for the development of mild cognitive impairment (MCI). It is still unclear whether the circadian rhythm plays any role for the incidence of MCI and precisely what.Design and method:
This is a cross-sectional study of 439 hypertensive patients. The mean age was 64.65 ± 10.15 years; males 160 (36.4%); females 279 (63.6%). The mean hypertension history was 11.10 ± 9.34 years. All were on combination medical therapy. The patients underwent full medical history, physical examination, laboratory screening, ECG, echocardiography, home and office blood pressure measurement, ambulatory blood pressure monitoring (ABPM), and cardio-vascular risk assessment. The neuropsychological screening for MCI was conducted via Montreal Cognitive Assessment (MoCA) and Mini Mental State Examination (MMSE). Geriatric depression scale (GDS) and the 4IADL were also applied. SPSS19 was used for the statistical analysis.Results:
The mean result for MoCA was 24.49 ± 3.5 and for MMSE – 27.94 ± 2.1 points. The mean values for the home measured blood pressure were 142.37 ± 17.72 mmHg for the systolic and 84.89 ± 10.43 mmHg for the diastolic. The mean values for the office blood pressure were 146.23 ± 22.35 mmHg for the systolic and 86.61 ± 11.71 mmHg for the diastolic. The mean results from the ABPM were above the recommended values both for the systolic, diastolic, day and night period. The dipping status was defined according the guidelines. The dippers were 151(34.40%); non-dippers – 174(40%); extreme dippers – 27(6.15%); reverse dippers – 90(20.50%). The dippers had higher (p = 0.005) MMSE score (28.38 ± 1.66) than non-dippers (27.74 ± 2.3), as well as than reverse dippers (27.52 ± 2.27 for MMSE, p = 0.001). The difference in the neuropsychological tests’ results between the groups of non-dippers, reverse dippers and extreme dippers was not significant.Conclusions:
Abnormal circadian rhythm is a risk factor for MCI in hypertensive patients with multiple risk factors. It may also be a clinical manifestation of hypertensive target-organ damage of the brain.