title: Chronotype is independently associated with glycemic control in type 2 diabetes.
abstract: OBJECTIVE
  To examine whether chronotype and daily caloric distribution are associated with glycemic control in patients with type 2 diabetes independently of sleep disturbances.
  
  
  METHODS
  Patients with type 2 diabetes had a structured interview and completed questionnaires to collect information on diabetes history and habitual sleep duration, quality, and timing. Shift workers were excluded. A recently validated construct derived from mid-sleep time on weekends was used as an indicator of chronotype. One-day food recall was used to compute the temporal distribution of caloric intake. Hierarchical linear regression analyses controlling for demographic and sleep variables were computed to determine whether chronotype was associated with HbA1c values and whether this association was mediated by a higher proportion of caloric intake at dinner.
  
  
  RESULTS
  We analyzed 194 completed questionnaires. Multiple regression analyses adjusting for age, sex, race, BMI, insulin use, depressed mood, diabetes complications, and perceived sleep debt found that chronotype was significantly associated with glycemic control (P = 0.001). This association was partially mediated by a greater percentage of total daily calories consumed at dinner.
  
  
  CONCLUSIONS
  Later chronotype and larger dinner were associated with poorer glycemic control in patients with type 2 diabetes independently of sleep disturbances. These results suggest that chronotype may be predictive of disease outcomes and lend further support to the role of the circadian system in metabolic regulation.
authors: Section of Endocrinology, Department of Medicine, Rush University Medical Center, Chicago, Illinois, USA. sreutrakul@yahoo.com
authors: Sirimon
authors: S
authors: Reutrakul
authors: Megan M
authors: MM
authors: Hood
authors: Stephanie J
authors: SJ
authors: Crowley
authors: Mary K
authors: MK
authors: Morgan
authors: Marsha
authors: M
authors: Teodori
authors: Kristen L
authors: KL
authors: Knutson
authors: Eve
authors: E
authors: Van Cauter
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism*; D002940:Circadian Rhythm / Q000502:physiology; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D002149:Energy Intake / Q000502:physiology; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D012890:Sleep / Q000502:physiology; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin
references: Chronobiologia. 1975 Jan-Mar;2(1):23-78
references: 1192905
references: Psychiatry Res. 1989 May;28(2):193-213
references: 2748771
references: Ergonomics. 1973 Mar;16(2):203-9
references: 4726654
references: J Physiol Anthropol. 2009 Mar;28(2):83-90
references: 19346668
references: Obesity (Silver Spring). 2009 Nov;17(11):2100-2
references: 19730426
references: Am J Respir Crit Care Med. 2010 Mar 1;181(5):507-13
references: 20019340
references: J Pers Soc Psychol. 1986 Dec;51(6):1173-82
references: 3806354
references: Science. 2005 May 13;308(5724):1043-5
references: 15845877
references: Sci Transl Med. 2012 Apr 11;4(129):129ra43
references: 22496545
references: Curr Biol. 2004 Dec 29;14(24):R1038-9
references: 15620633
references: Int J Obes (Lond). 2008 Apr;32(4):658-62
references: 18071340
references: Obesity (Silver Spring). 2011 Jul;19(7):1374-81
references: 21527892
references: Sleep Med Rev. 2007 Dec;11(6):429-38
references: 17936039
references: Cell Metab. 2007 Nov;6(5):414-21
references: 17983587
references: Proc Natl Acad Sci U S A. 2007 Sep 4;104(36):14412-7
references: 17728404
references: Ann Intern Med. 1999 Oct 5;131(7):485-91
references: 10507956
references: Int J Obes (Lond). 2012 Nov;36(11):1436-41
references: 22310473
references: J Clin Invest. 2011 Jun;121(6):2133-41
references: 21633182
references: Diabetol Metab Syndr. 2012 May 02;4(1):18
references: 22551206
references: Curr Biol. 2012 May 22;22(10):939-43
references: 22578422
references: Chronobiol Int. 2006;23(1-2):497-509
references: 16687322
references: Nat Genet. 2012 Jan 29;44(3):297-301
references: 22286214
references: Sleep Med. 2007 Sep;8(6):578-89
references: 17481949
references: Endocr Rev. 1997 Oct;18(5):716-38
references: 9331550
references: Best Pract Res Clin Endocrinol Metab. 2010 Oct;24(5):785-800
references: 21112026
references: J Biol Rhythms. 2003 Feb;18(1):80-90
references: 12568247
references: Diabetes. 1999 Nov;48(11):2182-8
references: 10535452
references: Proc Natl Acad Sci U S A. 2009 Mar 17;106(11):4453-8
references: 19255424
references: Eff Clin Pract. 2000 Jan-Feb;3(1):7-15
references: 10788040
references: Nat Rev Endocrinol. 2009 May;5(5):253-61
references: 19444258
references: Chronobiol Int. 2011 Nov;28(9):771-8
references: 21895489
references: Arch Intern Med. 2006 Sep 18;166(16):1768-74
references: 16983057
references: Arch Intern Med. 2005 Feb 28;165(4):447-52
references: 15738376