Diminished Melatonin Secretion in the Elderly Caused by Insufficient Environmental Illumination1

• DOI: 10.1210/jcem.86.1.7097
• Publication Date: 2014-01-08T17:06:14Z
• Authors: K. Mishima; M. Okawa; T. Shimizu; Y. Hishikawa
• Keywords: Sleep; Senescence

The pineal hormone melatonin has some circadian regulatory effects and is assumed to have a close relation with sleep initiation maintenance. Many previous reports described age-related decreases in levels, especially elderly insomniacs (EIs), which may act as causal or exacerbating factors disturbances the elderly. Ten residents psychophysiological insomnia (mean age, 74.2 yr), 10 healthy of same home [elderly control (EC) group; mean 72.7 yr], young subjects 20.9 yr) living at participated this study. persons, EIs, were exposed significantly less environmental light simultaneously suffered from diminished nocturnal secretion. Supplementary exposure 4 h (1000 1200 h, 1400 1600 h) midday bright EI group increased secretion levels similar those without phase-shifting. There was tendency for magnitude increase stimulated by parallel amelioration these subjects. present findings suggest that we need pay attention individuals who suffer under conditions poor resulting disorganized rhythms, including sleep-wake cycle.