Abstract
INTRODUCTION: Diastolic blood pressure (DBP), which is influenced by cardiac output and total peripheral resistance, normally remains stable or decreases during the transition from rest to exercise. Dyslipidemia has been shown to attenuate vasodilation, and may therefore impede the normal reduction in peripheral vascular resistance during exercise. This investigation examines differences in lipid levels between apparently healthy individuals with a normal and hypertensive DBP response to exercise.
METHODS: From a pool of 275 apparently healthy subjects, 35 individuals (aged 57.8 +/- 15.0 years, 13 men and 22 women) with a normal DBP at rest (<80 mm Hg) that increased to a hypertensive level at maximal exercise (>=90 mm Hg) were randomly age and sex matched to 35 subjects (aged 56.5 +/- 13.4 years) with a normal DBP at rest (<80 mm Hg) that remained below a hypertensive level at maximal exercise (<90 mm Hg).
RESULTS: A paired t test revealed DBP to be significantly higher in the group with an abnormal response to exercise (97.0 +/- 7.6 mm Hg vs 76.8 +/- 7.4 mm Hg; P < .001). Total cholesterol (204.2 +/- 31.2 mg/dL vs 190.6 +/- 28.9 mg/dL; P < .05) and low-density lipoprotein (126.5 +/- 30.5 mg/dL vs 109.8 +/- 25.5 mg/dL; P < .05) levels were also significantly higher in the group with an abnormal DBP response to exercise. All other variables were similar between groups.
DISCUSSION: Results indicate that elevated lipid levels are associated with a hypertensive DBP response during maximal exercise in apparently healthy individuals. The abnormal DBP response to exercise observed in this study may be related to attenuated vasodilation in skeletal muscle induced by higher levels of low-density lipoprotein.