Circadian misalignment increases cardiovascular disease risk factors in humans

TLDR

Shift work is linked to hypertension, inflammation, and cardiovascular disease, partly due to circadian misalignment, but the direct effect of misalignment on 24‑h blood pressure and inflammatory markers remains unclear. In controlled experiments, short‑term circadian misalignment raised 24‑h blood pressure and inflammatory markers in healthy adults, offering a mechanistic explanation for shift‑work–associated cardiovascular risk.

Abstract

Significance Shift work is a risk factor for hypertension, inflammation, and cardiovascular disease, even after controlling for traditional risk factors. Shift workers frequently undergo circadian misalignment (i.e., misalignment between the endogenous circadian system and 24-h environmental/behavioral cycles). This misalignment has been proposed to explain, in part, why shift work is a risk factor for hypertension, inflammation, and cardiovascular disease. However, the impact of circadian misalignment per se on 24-h blood pressure and inflammatory markers is poorly understood. We show—under highly controlled laboratory conditions—that short-term circadian misalignment increases 24-h blood pressure and inflammatory markers in healthy adults. Our findings may help explain why shift work increases hypertension, inflammation, and cardiovascular disease risk.