PS-C25-10: ASSOCIATION BETWEEN SKELETAL MUSCLE MASS AND BLOOD PRESSURE DECLINE OVER A FIVE-YEAR PERIOD FOR COMMUNITY-DWELLING OLDER ADULTS

Abstract

Objective: To determine the association between skeletal muscle mass and systolic blood pressure decline over a 5-year period in older adults over 75 years old. Methods: Of those who got health checkups at private A clinic from May 2020 to March 2021, 118 subjects for whom data on systolic blood pressure (SBP) levels consequently collected for five years were included. Skeletal muscle mass was measured at the health checkup in this clinic, and the Skeletal Muscle Index (SMI) was calculated by dividing the sum of limb muscle mass by the square of height using the multi-frequency bioimpedance method. Lower SMI was classified as a relative skeletal muscle mass index less than 7.0 kg/m2 and 5.7 kg/m2 in men and women, respectively. SBP levels used the mean of office SBP at A clinic visits in 2020 and 2015. 5-year SBP changes were calculated and categorized into two groups: SBP decline group (decline of -3 or more) and SBP maintenance group. The main outcome was SBP decline, and the association with SMI was examined by chi-square test and logistic regression analysis adjusted for age and gender. Results: The mean age of the subjects was 81.1 ± 4.5 years, 76 (64.4%) were female, 76(64.4%) were taking anti-hypertensive medication, 40(33.9%) were lower SMI, and 39 (33.1%) for SBP decline group. The SBP decline group had a lower BMI and a higher percentage of lower SMI than the maintenance group (p < 0.05). Furthermore, logistic regression analysis showed that lower SMI was independently associated with SBP decline (odds ratio: 2.44, 95% CI: 1.07–5.54). Conclusion: Our results suggest that there may be an association between lower SMI and SBP decline over a 5-year period in community-dwelling older adults over 75 years old. Long term changes of SBP might be the useful biomarker for muscle mass decline for older adults, although further mechanistic investigations are necessary.