Quantity of sleep is known to affect cardiovascular events. This study aimed to evaluate the chronic effect of quantity and quality of sleep on electrocardiographic indices like QT interval, heart rate-corrected QT interval (QTc), QT dispersion (QTd) and QTc dispersion (cQTd) among healthy young adults.
Method: 101medical students (39 women) in the age group of 18 to 22 years were included. Self reported duration of sleep and sleep latency was noted for past month. The quality of sleep assessed using the Pittsburgh Sleep Quality Index (PSQI).QT, QTc, QTd, cQTd were measured from ECG recordings of the subjects.
The analysis of the data was done by grouping and comparing the subjects according to sleep duration (<7 and >7 hours) PSQI scores (in <5 & >5) and sleep latency (<30min and > 30min).
Results: The mean and SD of electrocardiographic indices studies for the whole sample were within the normal limits. There was no significant statistical difference observed in QT, QTc, QTd, cQTd values among the respective groups though the values tend to be shorter in the groups with PSQI >5,sleep duration<7 hours & with sleep latency >15 minutes. QT, QTc, QTd, cQTd were inversely correlated with PSQI and sleep latency directly sleep duration respectively.
Conclusion: The quantity and quality of sleep during past one month does not influence electrocardiographic indices in healthy young adults
Ikehara S, Iso H, Date C, Kikuchi S, Watanabe Y, Wada Y, Inaba Y, Tamakoshi A; JACC Study Group. Association of sleep duration with mortality from cardiovascular disease and other causes for Japanese men and women: the JACC study. Sleep. 2009 Mar 1; 32(3):295-301.
Ayas NT, White DP, Manson JE, Stampfer MJ, Speizer FE, Malhotra A, Hu FB. A prospective study of sleep duration and coronary heart disease in women. Arch Intern Med. 2003 Jan 27; 163(2):205-9.
Ozer O, Ozbala B, Sari I, Davutoglu V, Maden E, Baltaci Y, Yavuz S, Aksoy M.Acute sleep deprivation is associated with increased QT dispersion in healthy young adults. Pacing Clin Electrophysiol. 2008 Aug; 31(8):979-84.
Sari I, Davutoglu V, Ozbala B, Ozer O, Baltaci Y, Yavuz S, Aksoy M.Acute sleep deprivation is associated with increased electrocardiographic P-wave dispersion in healthy young men and women. Pacing Clin Electrophysiol. 2008 Apr; 31(4):438-42.
Pilcher JJ, Ginter DR, Sadowsky B. Sleep quality versus sleep quantity: relationships between sleep and measures of health, well-being and sleepiness in college students. J Psychosom Res. 1997 Jun; 42(6):583-96.
Suzuki E, Yorifuji T, Ueshima K, Takao S, Sugiyama M, Ohta T, Ishikawa-Takata K, Doi H. Sleep duration, sleep quality and cardiovascular disease mortality among the elderly: A population-based cohort study. Prev Med. 2009 Aug-Sep:49(2-3):135-41.
Bysse DJ, Reynolds CFI, Monk TH, Berman SR, Kupfer DJ. The Pittsburg Sleep Quality index: A new instrument for psychiatric practice and research, Psychiatry Res. 1989; 28:93-213.
de Bruyne MC, Hoes AW, Kors JA, Hofman A, van Bemmel JH, Grobbee DE. QTc dispersion predicts cardiac mortality in the elderly: the Rotterdam Study. Circulation 1998 Feb 10; 97(5):467-72.
Perkiömäki JS, Koistinen MJ, Yli-Mäyry S, Huikuri HV.Dispersion of QT interval in patients with and without susceptibility to ventricular tachyarrhythmias after previous myocardial infarction. J Am Coll Cardiol. 1995 Jul; 26(1):174-9.
Elming H, Holm E, Jun L, Torp-Pedersen C, Kober L, Kircshoff M, Malik M, Camm J: The prognostic value of the QT interval and QT interval dispersion in all-cause and cardiac mortality and morbidity in a population of Danish citizens. Eur Heart J 1998; 19:1391-1400.
Voderholzer U, Hohagen F., Klein T., Jungnickel J, Kirschbaum C, Berger M, Riemann D, Impact of Sleep Deprivation and Subsequent Recovery Sleep on Cortisol in Unmediated Depressed Patients. Am J Psychiatry 161:1404- 1410.
