Does aging alter skin vascular function in humans when spatial variation is considered?

Area of Science:

• Physiology
• Vascular Biology
• Aging Research

Background:

• Age-related changes in cutaneous vascular function are debated, with mixed findings on venoarteriolar reflex (VAR) and post-occlusive reactive hyperemia (PORH).
• Regional variability in skin blood flow measurements may contribute to inconsistent results.

Purpose of the Study:

• To investigate the hypothesis that aging attenuates VAR and PORH responses in forearm skin.
• To account for potential inter-site variability by assessing responses across four adjacent skin sites.

Main Methods:

• Twenty young (24±4 years) and twenty older (60±7 years) adults participated.
• VAR and PORH were induced via venous and arterial occlusion, respectively.
• Cutaneous blood flow was measured using laser-Doppler flowmetry, with averaged responses from multiple sites.

Main Results:

• VAR and PORH responses were largely similar between young and older adults.
• A slight delay in achieving peak PORH was observed in older adults (5.5±4.4 s, p=0.003).

Conclusions:

• Aging has a negligible influence on venoarteriolar reflex and post-occlusive reactive hyperemia in forearm skin.
• These findings hold true even when controlling for region-specific variability in vascular responses.