Background: Aging is associated with progressive loss of muscle strength. Muscle tissue is vascularized by an elaborate vascular network. There is evidence that blood pressure (BP) is associated with muscle function in middle age. It is unknown how BP associates with muscle function in oldest old people. We studied the association between BP and handgrip strength in middle and old age.
Method: BP was measured automatically in middle-aged subjects and with a mercury sphygmomanometer in the oldest old. Handgrip strength was measured with a handgrip strength dynamometer. Cross-sectional measurements of handgrip strength and BP were available for 670 middle-aged subjects (mean 63.2 ± 6.6 years) and 550 oldest old subjects (all 85 years). Prospective data were available for oldest old subjects only with a 4-year follow-up at 89 years. The association between BP and handgrip strength was analyzed by linear regression analysis.
Results: In middle-aged subjects, BP and handgrip strength were not statistically significantly associated. In oldest old subjects, higher systolic BP (SBP), mean arterial pressure (MAP), and pulse pressure (PP) were associated with higher handgrip strength after adjusting for comorbidity and medication use (all P < 0.02). Furthermore, in oldest old subjects, changes in SBP, MAP, and PP after 4 years was associated with declining handgrip strength (all, P < 0.05).
Conclusion: In oldest old, higher BP is associated with better muscle strength. Further study is necessary to investigate whether BP is a potential modifiable risk factor for prevention of age-associated decline in muscle strength.