Journal
JOURNAL OF HYPERTENSION
Volume 39, Issue 8, Pages 1678-1688Publisher
LIPPINCOTT WILLIAMS & WILKINS
DOI: 10.1097/HJH.0000000000002848
Keywords
actigraphy; ambulatory blood pressure monitoring; cardiometabolic risk; circadian rhythm; dipper status; glucose tolerance; lifestyle; night-time blood pressure; sympathetic nervous system
Categories
Funding
- European Union's Seventh Framework Programme for research, technological development and demonstration [278397]
Ask authors/readers for more resources
The study found that timed light therapy for rotating night shift workers can improve their diurnal blood pressure control and glucose tolerance, increasing the proportion of dippers and reducing catecholamine levels.
Objectives: 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. Methods: 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. Results: 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). Conclusion: 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.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available