Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Sleep, Chronobiology and Addiction Research Group, University of Surrey, Guildford, Surrey, England.
J Hypertens. 2021 Aug 1;39(8):1678-1688. doi: 10.1097/HJH.0000000000002848.
Night shift work is associated with high rates of hypertension and cardiometabolic disease, which are linked to disrupted circadian rhythms. We hypothesized that timed light therapy might improve disrupted circadian rhythms and stabilize diurnal control of blood pressure and glucose in night shift workers.
We randomized 24 rotating night shift workers (mean age, 36 ± 13 years, 7 men) who had spent a median of 6 years on rotating night shifts (median, six night shifts per month) to 12 weeks of light therapy or no intervention and compared them with 12 daytime workers (37 ± 11 years, 6 men). We measured oral glucose tolerance (OGTT), 24-h blood pressure and arterial stiffness, and the circadian profiles of melatonin, cortisol, metanephrine and nor-metanephrine at baseline, after 12 weeks of intervention, and 12 weeks after the end of intervention.
At baseline, fewer night shift workers showed dipper status as compared with daytime workers (29 vs. 58%; P < 0.001). After 12 weeks of light therapy, there was a highly significant increase in the proportion of dippers (to 58%; P < 0.0001). We also observed a significant decrease in serum glucose during OGTT in the light therapy group (-22%; P < 0.05) with no change in serum insulin. Whilst circadian profiles of melatonin and cortisol were unchanged, plasma metanephrine and nor-metanephrine levels were significantly reduced in the light therapy group (P < 0.01).
Timed light therapy improves diurnal blood pressure control and glucose tolerance in rotating night shift workers. This effect is unrelated to melatonin and cortisol but is paralleled by reduced catecholamine levels.
夜班工作与高血压和心血管代谢疾病的高发病率有关，这些疾病与昼夜节律紊乱有关。我们假设定时光疗可能改善昼夜节律紊乱，并稳定夜班工作者的日间血压和血糖控制。
我们将 24 名轮班夜班工作者（平均年龄 36±13 岁，7 名男性）随机分为 12 周光疗组或无干预组，并与 12 名日间工作者（37±11 岁，6 名男性）进行比较。我们在基线、干预 12 周后和干预结束后 12 周时测量口服葡萄糖耐量（OGTT）、24 小时血压和动脉僵硬，以及褪黑素、皮质醇、甲肾上腺素和去甲肾上腺素的昼夜节律。
基线时，与日间工作者相比，较少的夜班工作者表现出夜间血压下降（29%对 58%；P<0.001）。经过 12 周的光疗后，夜间血压下降的比例显著增加（至 58%；P<0.0001）。我们还观察到光疗组 OGTT 期间血清葡萄糖显著降低（-22%；P<0.05），而血清胰岛素无变化。虽然褪黑素和皮质醇的昼夜节律没有改变，但光疗组的血浆甲肾上腺素和去甲肾上腺素水平显著降低（P<0.01）。
定时光疗可改善轮班夜班工作者的日间血压控制和葡萄糖耐量。这种效果与褪黑素和皮质醇无关，但与儿茶酚胺水平降低有关。
