TY - JOUR
T1 - Circadian rhythm disruption in severe sepsis
T2 - The effect of ambient light on urinary 6-sulfatoxymelatonin secretion
AU - Verceles, Avelino C.
AU - Silhan, Leann
AU - Terrin, Michael
AU - Netzer, Giora
AU - Shanholtz, Carl
AU - Scharf, Steven M.
PY - 2012/5
Y1 - 2012/5
N2 - Purpose: Properly regulated circadian rhythm supports physical and immunologic function. This rhythm is disrupted in patients with critical illness. We assessed the association between ambient light and circadian melatonin release, measured by urinary 6-sulfatoxymelatonin (6-SMT), in medical intensive care unit (MICU) patients with severe sepsis. Methods: After excluding patients for renal failure or hepatic failure, blindness, and intracranial disease, seven patients were studied. No environmental manipulation was performed. Urinary 6-SMT specimens were obtained every 4 h. Light was measured in 1-min epochs for two sequential 24-h periods and compared to 6-SMT levels. Results: No significant differences among urinary 6-SMT levels were found across 4-h time periods or between the 2 days (range 1,190.26 ± 1,040.81-4,738.57 ± 5,543.08 ng, 4-h period p = 0.09, 24-h day p = 0.50). Light levels were low and differed among 4-h periods, but not 24-h averages (minimum 2.32 ± 3.65 lux/min 00:01-04:00, maximum 70.11 ± 79.12 lux/min from 12:01-16:00, 4 h period p =\0.001, 24 h period p = 0.53). There was no relationship between light levels and 6-SMT excretion. Conclusions: Circadian rhythm was disrupted in patients with severe sepsis, as reflected by disordered diurnal variation of urinary 6-SMT excretion. Light levels were low, exhibited limited diurnal variation, and did not entrain circadian rhythms in these patients.
AB - Purpose: Properly regulated circadian rhythm supports physical and immunologic function. This rhythm is disrupted in patients with critical illness. We assessed the association between ambient light and circadian melatonin release, measured by urinary 6-sulfatoxymelatonin (6-SMT), in medical intensive care unit (MICU) patients with severe sepsis. Methods: After excluding patients for renal failure or hepatic failure, blindness, and intracranial disease, seven patients were studied. No environmental manipulation was performed. Urinary 6-SMT specimens were obtained every 4 h. Light was measured in 1-min epochs for two sequential 24-h periods and compared to 6-SMT levels. Results: No significant differences among urinary 6-SMT levels were found across 4-h time periods or between the 2 days (range 1,190.26 ± 1,040.81-4,738.57 ± 5,543.08 ng, 4-h period p = 0.09, 24-h day p = 0.50). Light levels were low and differed among 4-h periods, but not 24-h averages (minimum 2.32 ± 3.65 lux/min 00:01-04:00, maximum 70.11 ± 79.12 lux/min from 12:01-16:00, 4 h period p =\0.001, 24 h period p = 0.53). There was no relationship between light levels and 6-SMT excretion. Conclusions: Circadian rhythm was disrupted in patients with severe sepsis, as reflected by disordered diurnal variation of urinary 6-SMT excretion. Light levels were low, exhibited limited diurnal variation, and did not entrain circadian rhythms in these patients.
KW - Critical illness
KW - Keywords Sepsis Circadian rhythm
KW - Melatonin Light
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U2 - 10.1007/s00134-012-2494-3
DO - 10.1007/s00134-012-2494-3
M3 - Article
C2 - 22286671
AN - SCOPUS:84862518671
SN - 0342-4642
VL - 38
SP - 804
EP - 810
JO - Intensive Care Medicine
JF - Intensive Care Medicine
IS - 5
ER -