Advancing age was associated with a greater decline in contractile response to isoproterenol in men (FS-sigma es slope -0.87 in young vs -0.41 in older) than in women (-0.55 vs -0.38).
Cross-Sectional (n=36)
Do age and gender affect the inotropic and chronotropic responses to beta-adrenergic stimulation with isoproterenol in healthy individuals?
Men exhibit a significantly greater age-associated decline in inotropic and chronotropic responses to beta-adrenergic stimulation compared to women.
We studied the effects of age and gender on cardiovascular responses to beta-adrenergic stimulation with the use of two-dimensional echocardiography in 16 young (aged 20-31) and 20 older (aged 60-75) healthy individuals. Following administration of atropine, each subject was given an infusion of isoproterenol at incremental doses from 0.010 to 0.030 microgram kg-1 min-1. The slopes of the fractional shortening-end-systolic wall stress (FS-sigma es) relationships were steeper in the young men (-0.87 +/- 0.28, n = 8) compared to the older men (-0.41 +/- 0.13, n = 10), and in the young women (-0.55 +/- 0.14, n = 8) compared to the older women (-0.38 +/- 0.13, n = 10). Furthermore, the magnitude of the age-associated differences in these slopes was larger in the men (old vs young) than in the women (old vs young) which, in the absence of changes in preload, suggests a greater decline in the contractile response to isoproterenol with advancing age in men compared to women. Furthermore, the men exhibited a greater attenuation of chronotropic response to isoproterenol than did the women. These observations suggest that gender plays a significant role in the age-associated decline in inotropic and chronotropic responses to beta-adrenergic stimulation, with men exhibiting a greater decline with aging than women.
Turner et al. (1999) conducted a cross-sectional in Healthy (n=36). Advancing age and male gender vs. Young age and female gender was evaluated on Slopes of the fractional shortening-end-systolic wall stress (FS-sigma es) relationships. Advancing age was associated with a greater decline in contractile response to isoproterenol in men (FS-sigma es slope -0.87 in young vs -0.41 in older) than in women (-0.55 vs -0.38).