Is mini-mental score examination (MMSE scoring) a new predictor of uncontrolled hypertension?

Abstract

Essential hypertension is still an important cardio-vascular morbidity and risk factor for many target organ damage. There still remain a large number of patients, especially in the under-developed countries who have an apparently controlled blood pressure (based on a single clinic visit) when it is actually poorly controlled. The brain is among the target organs infrequently visited by researchers. This is probably due to the common occurrence of systemic hypertension and non-hypertensive atherosclerosis in the elderly. Similarly, vascular and non-vascular dementia may also be seen. The separation of these different pathological entities for studying the sole effect of hypertension on the CNS is difficult. We aimed to evaluate whether the abnormal MMSE score predicts an un-controlled hypertension, confirmed by the 24-h Ambulatory Blood Pressure Monitoring (24-h ABPM), even if the office blood pressure measurement is normal. Seventy seven patients were included. All patients were aged 65 years old or above, with history of hypertension and are on treatment (even if their office blood pressure was within the normal range). All patients had clinic and 24-hour ABPM. The cognitive function of each patient was assessed by using mini-mental state examination (MMSE) and a customized simple brain MRI study. Patients with other causes of dementia and diabetes were excluded from the study. Patients were classified into a normal cognitive function group ( n = 19), a mild ( n = 9), moderate ( n = 38) and severe cognitive impairment ( n = 11) groups. The deep white matter hyperintensities were scored according to the modified Scheltens score. Significance level for the used tests is p = 0.05. The mean age was 68.8 ± 3.4 years old. The distribution of gender, smoking and dyslipidemia among the 4 groups was not significant. The hypertension duration, office and 24-h ABPM BP measurements and MRI score varied significantly between the 4 groups ( p < 0.0005). The hypertension duration and the average awake systolic blood pressure had the stronger impact on the MMSE class of the patient ( R 2 = 0.87, p < 0.0005). Classifying the patients into controlled and uncontrolled hypertensives, we had a higher percentage of uncontrolled BP in every cognitive impairment class. Only 1 patient with normal cognitive function had an uncontrolled hypertension. MMSE score has a sensitivity and specificity of 94% and 83% respectively in the prediction of uncontrolled hypertension. We conclude that MMSE is a simple test to run in clinic and can give an idea about the degree of structural damage caused to the brain; and hence predict whether or not the patient’s BP is well controlled. This would not replace the 24-hour ABPM but may help guide the clinicians to request this 24-hour monitoring.