Abstract 363: Better Control of Blood Pressure in Midlife was Associated with Cognitive Function in Old Age: The Minabe Study in Japan

Abstract

Several studies show that hypertension in midlife is also related to cognitive impairment in old age. However, the associations between blood pressure and cognitive functions have been inconclusive. In this study, we examined this association in the sexagenarian and the septuagenarian separately to test our hypothesis that different risk factors were related to cognitive decline in each generation respectively. Participants were 1476 community-dwelling persons without dementia (708 men and 768 women). Resting systolic and diastolic blood pressures were measured in the seated position using an automated sphygmomanometer (HEM-907; Omron). The cognitive functions were measured by means of logical memory test, D-CAT (digit cancellation test; neuropsychological test for attention) and verbal fluency test. We asked participants about their use of antihypertensive drug and collected their data about blood pressure measured at a health examination conducted ten years ago. We constructed a series of multiple linear regression models to examine the association of blood pressure with each cognitive function. Separate analyses were conducted for each combination of predictor (SBP, DBP, past SBP, past DBP, and use of antihypertensive drug) and dependent value (logical memory test, D-CAT, and verbal fluency test). Regression models included the following covariates: age, education, gender, and body mass index. Results indicated the following two points: (1) Higher levels of past DBP (β = -.121, p < .05) was associated with decline in logical memory test and higher level of past SBP (β = -.127, p < .05) was associated with decline in verbal fluency test in the sexagenarian, (2) The use of antihypertensive drug was associated with decline in D-CAT (β = -.194, p < .001) and verbal fluency test (β = -.196, p < .05) in the septuagenarian. Our findings suggest that high blood pressure in the past decade is risk factor for cognitive decline in the sexagenarian but is not risk factor in the septuagenarian. The treatment of high blood pressure in midlife is important for the maintenance of cognitive functions. Early control of high blood pressure might reduce the risk of cognitive impairment in old age.