Table 1.
Clinical studies examining the association between sleep duration with obesity and diabetes
| Author (year) | Type of study/country or region | Study population (sample size) | Definition of sleep disturbances | Method of sleep assessment | Age (yr) and male (%) | Outcome |
|---|---|---|---|---|---|---|
| Sleep duration and overweight/obesity | ||||||
| Ayas et al. (2003)11 | Prospective (mean follow-up: 10 yr)/the United States | Female married registered nurses from the Nurses’ Health Study (n=70,026) | Short sleep: ≤5 hr/day Long sleep: ≥9 hr/day Reference: 8 hr/day |
Self-reported sleep duration | 40–65, 0% | New-onset obesity Short sleep: RR, 1.18; 95% CI, 0.96–1.44 Long sleep: RR, 1.29; 95% CI, 1.05–1.59 |
| Patel et al. (2006)56 | Prospective study (follow-up: 16 yr)/the United States | Female nurses from the Nurses’ Health Study (n=68,183) | Sleep duration was categorized as: ≤5, 6, 7, 8, and ≥9 hr/day Reference: 7 hr/day |
Self-reported | 39–65, 0% | New-onset obesity Sleep duration ≤5 hr/day: HR, 1.15; 95% CI, 1.04–1.27 Sleep duration 6 hr/day: HR, 1.06; 95% CI, 1.01–1.12 Sleep duration ≥9 hr/day: HR, 1.03; 95% CI, 0.93–1.14 ≥15 kg weight gain Sleep duration ≤5 hr/day: HR, 1.28; 95% CI, 1.15–1.42 Sleep duration 6 hr/day: HR, 1.10; 95% CI, 1.04–1.17 Sleep duration ≥9 hr/day: HR, 1.04; 95% CI, 0.92–1.16 |
| Chaput et al. (2008)57 | Prospective study (follow-up: 6±0.9 yr)/Canada | General population form the Quebec Family Study (n=276; nonobese: n=224) | Short sleep: 5–6 hr/day Long sleep: 9–10 hr/day Reference: 7–8 hr/day |
Self-reported | 21–64, 42.4% | Weight gain Short-duration sleepers gained 1.84 kg; 95% CI, 1.08–2.61 Long-duration sleepers gained 1.49 kg; 95% CI, 0.92–2.48 New-onset obesity Short-duration sleepers: OR, 1.27; 95% CI, NS Long-duration sleepers: OR, 1.21; 95% CI, NS |
| López-García et al. (2008)58 | Prospective study (follow-up: 2 yr)/Spain | Elderly population (n=3,235) | Sleep duration was categorized as: ≤5, 6, 7, 8, 9, and ≥10 hr/day Reference: 7 hr/day |
Interview | Male, 71.6±8.0; female, 72.1±7.6, 43.6% | ORs of obesity Sleep ≤5 hr: OR, 1.33; 95% CI, 1.00–1.77 Sleep 8 hr: OR, 1.39; 95% CI, 1.11–1.75 ORs of severe obesity Sleep ≤5 hr: OR, 2.08; 95% CI, 1.31–3.32 Sleep 8 hr: OR, 1.82; 95% CI, 1.21–2.73 Sleep 9 hr: OR, 1.57; 95% CI, 1.00–2.47 Weight gain ≥5 kg In women sleeping ≤5 hr: OR, 3.41; 95% CI, 1.34–8.69 In women sleeping 8 hr: OR, 3.03; 95% CI, 1.29–7.12 In women sleeping 9 hr: OR, 3.77; 95% CI, 1.55–9.17 In total or men: no significant findings |
| Stranges et al. (2008)59 | Prospective study (follow-up: 1997–1999 to 2003–2004)/the United Kingdom | White-collar British civil servants from the Whitehall II Study (n=10,308) | Short sleep: ≤5 hr/day Normal sleep: 7 hr/day |
Self-reported | 35–55, 72.1% | Changes in BMI Short sleep: β, –0.06; 95% CI, −0.26–0.14 Changes in WC Short sleep: β, 0.44; 95% CI, −0.23–1.12 New-onset obesity Short sleep: OR, 1.05; 95% CI, 0.60–1.82 |
| Nishiura et al. (2010)60 | Prospective study (follow-up: 4 yr)/Japan | Nonobese Japanese male workers (n=2,632) | Short sleep: <6 hr/day Normal sleep: 7–7.9 hr/day |
Self-reported | 40–59, 100% | New-onset obesity Short sleep: OR, 2.46; 95% CI, 1.41–4.31 |
| Watanabe et al. (2010)61 | Prospective study (follow-up: 1 yr)/Japan | Employees for an electric power company (n=23,212) | Sleep duration was categorized as: <5, 5–<6, 6–<7, 7–<8, 8–<9, and ≥9 hr/day Reference: 7–<8 hr/day |
Self-reported | 39.8±9.6, 86.3% | Weight gain Male with sleep <5 hr/day: β, 0.016; 95% CI, 0.024–0.146; P<0.01 Male with sleep <5 hr/day: β, 0.013; 95% CI, 0.001–0.061; P=0.04 Male with sleep ≥9 hr/day: β, 0.018; 95% CI, 0.079–0.340; P<0.01 New-onset obesity Male with sleep <5 hr/day: OR, 1.91; 95% CI, 1.36–2.67 Male with sleep 5–6 hr/day: OR, 1.50; 95% CI, 1.24–1.80 No significant association between sleep duration and weight gain or obesity was found for women. |
| Itani et al. (2011)62 | Prospective study (follow-up: 7 yr)/Japan | Workers in a local government organization (n=22,743) | Short sleep: <5 hr/day Normal sleep: 5–7 hr/day |
Self-reported | NS, 95.4% | New-onset obesity Male subjects with short sleep: RR, 1.20; 95% CI, 1.09–1.32 Female subjects with short sleep: RR, 1.71; 95% CI, 1.11–2.87 |
| Lyytikäinen et al. (2011)63 | Prospective study (follow-up: 5–7 yr)/Finland | Middle-aged municipal employees from the Helsinki Health Study (n=7,027) | Short sleep: ≤5 hr/day Long sleep: ≥9 hr/day Reference: 7 hr/day |
Self-reported | 40–60, 18.5% | Weight gain ≥5 kg Female with short sleep: OR, 1.42; 95% CI, 1.01–2.01 Female with long sleep: OR, 1.30; 95% CI, 0.97–1.76 Male with short sleep: OR, 0.88; 95% CI, 0.44–1.74 Male with long sleep: OR, 1.06; 95% CI, 0.48–2.32 |
| Kobayashi et al. (2012)64 | Prospective study (follow-up: 3 yr)/Japan | Healthy population (n=11,136) | Sleep duration was categorized as: ≤5, 6, 7, and ≥8 hr/day Reference: 7 hr/day |
Self-reported | ≥20, 44.0% | Weight gain Sleep ≤5: β coefficient, 0.03; 95% CI, 0.03–1.1; P=0.02 Sleep ≥8: β coefficient, 0.01; 95% CI, −0.03–0.1; P=0.34 New-onset obesity Sleep ≤5: OR, 1.5; 95% CI, 1.1–2.0 Sleep ≥8: OR, 1.3; 95% CI, 0.9–1.8 |
| Yiengprugsawan et al. (2012)65 | Prospective study (follow-up: 4 yr)/Thailand | Distance learners at Sukhothai Thammathirat Open University (n=60,569) | Sleep duration was categorized as <6, 6, 7, 8 and ≥9 hr/day; Short sleep: <6 hr/day Long sleep: ≥9 hr/day Reference: 7 hr/day |
Self-reported | 35.6 (20–49), 45.2% | Overweight Female with short sleep: OR, 1.33; 95% CI, 1.18–1.51 Female with long sleep: OR, 1.22; 95% CI, 1.07–1.39 Male with short sleep: OR, 1.13; 95% CI, 1.00–1.28 Male with long sleep: OR, 1.03; 95% CI, 0.91–1.16 New-onset obesity Female with short sleep: OR, 1.49; 95% CI, 1.32–1.68 Female with long sleep: OR, 1.36; 95% CI, 1.20–1.53 Male with short sleep: OR, 1.36; 95% CI, 1.21–1.52 Male with long sleep: OR, 1.16; 95% CI, 1.03–1.30 |
| Nagai et al. (2013)66 | Prospective study (follow-up: 11 yr)/Japan | General population (n=9,658) | Short sleep: ≤5 hr/day Long sleep: ≥9 hr/day Reference: 7 hr/day |
Self-reported | 40–79, NS | Weight gain ≥5 kg Total subjects with short sleep: OR, 0.93; 95% CI, 0.73–1.20 Total subjects with long sleep: OR, 1.05; 95% CI, 0.91–1.20 BMI ≥25 kg/m2 with short sleep: OR, 0.86; 95% CI, 0.58–1.29 BMI ≥25 kg/m2 with long sleep: OR, 1.36; 95% CI, 1.09–1.70 New-onset obesity Short sleep: OR, 1.08; 95% CI, 0.77–1.51 Long sleep: OR, 1.06; 95% CI, 0.86–1.29 |
| Ohkuma et al. (2013)67 | Cross-sectional study/Japan | Japanese patients with T2DM (n=4,870) | Sleep duration was categorized as: <4.5, 4.5–5.4, 5.5–6.4, 6.5–7.4, 7.5–8.4, and ≥8.5 hr/day; Reference: 6.5–7.4 hr/day |
Self-reported | ≥20, 57% | ORs (95% CIs) for obesity Sleep <4.5 hr/day: OR, 1.78; 95% CI, 1.26–2.52 Sleep ≥8.5 hr/day: OR, 1.24; 95% CI, 0.97–1.58 P for quadratic trend: <0.001 |
| Sayón-Orea et al. (2013)68 | Prospective study (median follow-up: 6.5 yr)/Spain | General population from the SUN Mediterranean Cohort (n=10,532) | Sleep duration was categorized as <5, 5–<7, 7–<8, ≥8 hr/night; Reference: 7–<8 hr/day | Self-reported | 39±12, NS | New-onset obesity Total with sleep <5 hr/night: HR, 1.94; 95% CI, 1.19–3.18 Male with sleep <5 hr/night: HR, 2.09; 95% CI, 1.18–3.69 Female with sleep <5 hr/night: HR, 1.26; 95% CI, 0.44–3.57 Total with sleep ≥8 hr/night: HR, 1.13; 95% CI, 0.89–1.43 Male with sleep ≥8 hr/night: HR, 0.88; 95% CI, 0.64–1.21 Female with sleep ≥8 hr/night: HR, 1.43; 95% CI, 0.97–2.10 |
| Xiao et al. (2013)69 | Prospective study (follow-up: 7.5 yr)/the United States | General population from the National Institutes of Health-AARP Diet and Health Study (n=83,377) | Sleep duration was categorized as <5, 5–6, 7–8, ≥9 hr/day; Reference: 7–8 hr/day |
Self-reported | 51–72, 51.8% | Weight gain ≥5 kg Male with sleep <5 hr/day: OR, 1.27; 95% CI, 1.07–1.52 Female with sleep <5 hr/day: OR, 1.30; 95% CI, 1.12–1.51 Male with sleep ≥9 hr/day: OR, 1.16; 95% CI, 0.99–1.36 Female with sleep ≥9 hr/day: OR, 1.02; 95% CI, 0.88–1.17 New-onset obesity Male with sleep <5 hr/day: OR, 1.45; 95% CI, 1.06–1.99 Female with sleep <5 hr/day: OR, 1.37; 95% CI, 1.04–1.79 Sleep duration ≥9 hr/day Male with sleep ≥9 hr/day: OR, 1.12; 95% CI, 0.84–1.49 Female with sleep ≥9 hr/day: OR, 0.91; 95% CI, NS |
| Vgontzas et al. (2014)70 | Prospective study (total follow-up: 7.5 yr; women: 4.5 yr; men: 10.5 yr)/the United States | General population from the Penn State Cohort (n=815) | Sleep duration was categorized as ≤5, 5–6, 6–7, ≥7 hr/night; Reference: ≥7 hr/night |
Self-reported (subjective) and PSG (objective) | 48.9±13.4, 50.5% | New-onset obesity Subjective sleep duration ≤5 hr/night: OR, 1.08; 95% CI, 0.48–2.41 Objective sleep duration ≤5 hr/night: OR, 0.51; 95% CI, 0.22–1.18 |
| Gutiérrez-Repiso et al. (2014)71 | Prospective study (follow-up: 11 yr)/Spain | General population from the Pizarra cohort study (n=1,145) | Short sleep: ≤7 hr/night Normal sleep: ≥8 hr/night | Self-reported | 18–65, 38.8% | ORs of becoming obese in subjects with short sleep At the 6-yr follow-up: OR, 1.99; 95% CI, 1.12–3.55 At the 11-yr follow-up: OR, 2.73; 95% CI, 1.47–5.04 |
| Kim et al. (2015)72 | Prospective study (follow-up: 2.6 yr)/Korea | General population from the ARIRANG Study (n=3,862) | Short sleep: <6 hr/day Long sleep: ≥10 hr/day Reference: 6–7.9 hr/day |
Self-reported | 40–70, 41.1% | New-onset metabolic syndrome Short sleep: OR, 1.41; 95% CI, 1.06–1.88 Long sleep: OR, 0.68; 95% CI, 0.39–1.17 High WC Short sleep: OR, 1.30; 95% CI, 0.98–1.69 Long sleep: OR, 0.97; 95% CI, 0.62–1.50 |
| Zhang et al. (2015)73 | Cross-sectional study/China | School-aged children (n=3,086) | Sleep duration was categorized as: ≤8.00, 8.01–9.00, 9.01–10.00, and >10 hr/night; Reference: >10 hr/night Sleep compensated group: (weekend [or holiday] sleep duration–weekday sleep duration)/weekday sleep duration×100% ≥10% Reference: noncompensated group |
Self-reported | 7–14, 52.1% | Risk of being overweight/obese Weekdays sleep ≤8.00 hr/night: OR, 1.995; 95% CI, 0.917–4.219 Weekends sleep ≤8.00 hr/night: OR, 2.691; 95% CI, 1.513–4.785 Long holidays sleep ≤8.00 hr/night: OR, 2.921; 95% CI, 1.630–5.323 Sleep compensation during weekends: OR, 1.197; 95% CI, 1.004–1.493 Sleep compensation during holidays: OR, 1.309; 95% CI, 1.052–1.630 |
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| ||||||
| Sleep duration and risk of diabetes | ||||||
| Ayas et al. (2003)11 | Prospective (mean follow-up: 10 yr)/the United States | Female married registered nurses from the Nurses’ Health Study (n=70,026) | Short sleep: ≤5 hr/day Long sleep: ≥9 hr/day Reference: 8 hr/day |
Self-reported | 40–65, 0% | New-onset symptomatic diabetes Short sleep: RR, 1.34; 95% CI, 1.04–1.72 Long sleep: RR, 1.35; 95% CI, 1.04–1.75 |
| Mallon et al. (2005)74 | Prospective (mean follow-up: 12 yr)/Sweden | General population (n=1,170) | Short sleep: ≤5 hr/night Long sleep: ≥9 hr/night Reference: 5–8 hr/night |
Self-reported | 45–65, 47.0% | New-onset diabetes Male with short sleep: RR, 2.8; 95% CI, 1.1–7.3 Female with short sleep: RR, 1.8; 95% CI, 0.5–6.8 Male with long sleep: NS Female with long sleep: RR, 2.9; 95% CI, 0.6–15.0 |
| Yaggi et al. (2006)75 | Prospective study (follow-up: 15–17 yr)/the United States | Men from the Massachusetts Male Aging Study without diabetes (n=1,139) | Average sleep duration was divided into: ≤5, 6, 7, 8, and >8 hr/night; Reference: 7 hr/night |
Self-reported | 40–70, 100% | New-onset diabetes Sleep ≤5 hr/night: RR, 1.95; 95% CI, 0.95–4.01 Sleep >8 hr/night: RR, 3.12; 95% CI, 1.53–6.37 Further adjusted for testosterone Sleep ≤5 hr/night: RR, 1.51; 95% CI, 0.71–3.19 Sleep >8 hr/night: RR, 2.81; 95% CI, 1.34–5.90 |
| Gangwisch et al. (2007)76 | Prospective study (follow-up: 8–10 yr)/the United States | General population from the First National Health and Nutrition Examination Survey I (n=8,992) | Short sleep: ≤5 hr/night Long sleep: ≥9 hr/night Reference: 7 hr/night |
Self-reported | 32–86, 37% | New-onset diabetes Short sleep: OR, 1.47; 95% CI, 1.03–2.09 Long sleep: OR, 1.52; 95% CI, 1.06–2.18 |
| Hayashino et al. (2007)77 | Prospective study (median follow-up: 4.2 yr)/Japan | Asian workers from High-risk and Population Strategy for Occupational Health Promotion Study (n=6,509) | Short sleep: sleep duration <6 hr/day Long sleep: ≥9 hr/day Reference: 6–7 hr/day |
Self-reported | 38.2 (19–69), 73.9% | New-onset diabetes Short sleep: HR, 1.15; 95% CI, 0.76–1.74 Long sleep: HR, 1.03; 95% CI, 0.62–1.70 |
| Beihl et al. (2009)78 | Prospective study (follow-up: 5 yr)/the United States | General population from the Insulin Resistance Atherosclerosis Study (n=900) |
Short sleep: ≤7 hr/night Long sleep: ≥9 hr/night Reference: 8 hr/night |
Self-reported | 40–69, 43.3% | New-onset diabetes Non-Hispanic whites and Hispanics with short sleep: OR, 2.36; 95% CI, 1.11–5.00 Non-Hispanic whites and Hispanics with long sleep: OR, 2.15; 95% CI, 0.50–9.30 African American with short sleep: OR, 0.63; 95% CI, 0.14–2.90 African American with long sleep: OR, 0.39; 95% CI, 0.02–7.19 |
| Chaput et al. (2009)79 | Longitudinal study (mean follow-up: 6.0±0.9 yr)/Canada | General population from the Quebec Family Study (n=276) | Short sleep: ≤6 hr/night Long sleep: ≥9 hr/night Reference: 7–8 hr/night |
Self-reported | 21–64, 42.4% | New-onset T2DM or IGT Short sleep: OR, 2.42; 95% CI, 1.49–3.33 Long sleep: OR, 2.31; 95% CI, 1.41–3.15 |
| Xu et al. (2010)80 | Prospective study (follow-up: 6 yr)/the United States | General population from the National Institutes of Health-American Association of Retired Persons Diet and Health cohort (n=164,399) | Average sleep duration was divided into: <5, 5–6, 7–8, and ≥9 hr/night; Reference: 7–8 hr/night Day napping was categorized as: none, <1 hr, and ≥1 hr/day; Reference: none |
Self-reported | 50–71, 56.8% | New-onset diabetes Sleep <5 hr/night: OR, 1.34; 95% CI, 1.20–1.50 Sleep 5–6 hr/night: OR, 1.06; 95% CI, 1.01–1.11 Sleep ≥9 hr/night: OR, 1.09; 95% CI, 0.97–1.22 Day napping <1 hr/day: OR, 1.23; 95% CI, 1.18–1.29 Day napping ≥1 hr/day: OR, 1.55; 95% CI, 1.45–1.66 Hours of day napping×night sleep on diabetes: P<0.0001; among participants with no napping, only short night sleeping was associated with higher occurrence of diabetes (OR, 1.32), whereas among those with ≥1 hr of napping, both long (OR, 1.55) and short (OR, 1.78) sleeping was associated with higher risk. |
| Kita et al. (2012)81 | Prospective, occupational-based study (follow-up: 4 yr)/Japan | Local government employees (n=3,570) | Short sleep: ≤5 hr/day Reference: >7 hr/day |
Self-reported | 35–55, 79.0% | New-onset diabetes Short sleep: OR, 5.37; 95% CI, 1.38–20.91 |
| von Ruesten et al. (2012)82 | Prospective study (mean follow-up: 7.8 yr)/Germany | General population from the European Prospective Investigation into Cancer and Nutrition-Potsdam Study (n=23,620) | Short sleep: <6 hr/day Long sleep: ≥9 hr/day Reference: 7–<8 hr/day |
Self-reported | 35–65, 38.6% | New-onset diabetes Short sleep: HR, 1.06; 95% CI, 0.80–1.40 Long sleep: HR, 1.05; 95% CI, 0.82–1.33 |
| Holliday et al. (2013)83 | Prospective study (mean follow-up: 2.3 yr)/Australia | General population from the 45 and Up Study (n=212,388) | Average sleep duration was categorized as: <6, 6–<7, 7–<8, 8–<9, 9–<10, and ≥10 hr/day; Reference: 7–<8 hr/day |
Self-reported | ≥45, 47.3% | New-onset diabetes Sleep <6 hr: HR, 1.29; 95% CI, 1.08–1.53 Sleep ≥10 hr: HR, 1.03; 95% CI, 0.88–1.19 |
| Gutiérrez-Repiso et al. (2014)71 | Prospective study (follow-up: 11 yr)/Spain | General population from the Pizarra cohort study (n=1,145) | Short sleep: ≤7 hr/night Reference: ≥8 hr/night |
Self-reported | 18–65, 38.8% | New-onset diabetes At the 6-yr follow-up, short sleep: OR, 1.96; 95% CI, 1.10–3.50 At the 11-yr follow-up, short sleep: OR, 1.28; 95% CI, 0.60–2.69 |
| Heianza et al. (2014)84 | Prospective study (follow-up: 8 yr)/Japan | Workers (n=38,987) | Average sleep duration was categorized as: <5.5, 5.5–<6.5, 6.5–<7.0, 7.0–7.5, >7.5–8.0, or >8.0 hr/day; Short sleep: <5.5 or 5.5–<6.5 hr/day; Reference: 7.0–7.5 hr/day |
Self-reported | 18–83, 64.2% | New-onset diabetes Sleep <5.5 hr: OR, 1.53; 95% CI, 1.19–1.97 Sleep 5.5–<6.5 hr: OR, 1.25; 95% CI, 1.10–1.42 Sleep >8 hr/day: OR, 1.03; 95% CI, 0.81–1.30 In age ≤45 yr, sleep <5.5 hr: OR, 1.61; 95% CI, 1.08–2.42 In age 46–59 yr, sleep <5.5 hr: OR, 1.56; 95% CI, 1.10–2.22 In age ≥60 yr, sleep <5.5 hr: OR, 1.72; 95% CI, 0.75–3.92 |
| Lou et al. (2015)85 | Prospective study (median follow-up: 5 yr)/China | General population (n=11,842) | Short sleep: ≤6 hr/night Long sleep: ≥8 hr/night Reference: 6–8 hr/night |
Self-reported | 44.8±14.7, 45.4% | New-onset T2DM Short sleep: RR, 1.67; 95% CI, 1.34–2.16 Long sleep: RR, 1.45; 95% CI, 1.02–1.77 |
| Kim et al. (2015)72 | Prospective study (follow-up: 2.6 yr)/Korea | General population (n= 3,862) | Short sleep: <6 hr/day Long sleep: ≥10 hr/day Reference: 6–7.9 hr/day |
Self-reported | 40–70, 41.1% | High blood glucose Short sleep: OR, 1.31; 95% CI, 0.96–1.79 Long sleep: OR, 0.56; 95 CI, 0.29–1.04 |
| Han et al. (2016)86 | Prospective Study (follow-up: 3–4.75 yr)/China | Retired employees from the Dongfeng-Tongji cohort (n=16,399) | Sleep duration was categorized as: <7, 7–<8 (reference), 8–<9, 9–<10, and ≥10 hr/night; afternoon napping was divided into: no napping (0 min, reference), 1–30, 31–60, 61–90, and >90 min |
Self-reported | 62.5, 43.2% | New-onset diabetes Sleep <7 hr/night: HR, 0.93; 95% CI, 0.72–1.19 Sleep ≥10 hr/night: HR, 1.42; 95% CI, 1.08–1.87 Napping >90 min: HR, 1.28; 95% CI, 1.03–1.59 Sleep duration ≥10 hr/night and napping >60 min: HR, 1.72; 95% CI, 1.03–2.85 |
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| Sleep duration and glycemic control | ||||||
| Knutson et al. (2006)87 | Cross-sectional study/the United States | African-American women and men with diabetes (n=161) | Perceived sleep debt: the difference between weekday sleep duration and preferred sleep duration | Self-reported | 57±12, 26.1% | Glycemic control (lnHbA1c) Sleep debt in patients without diabetic complications: β, 0.51; P=0.04 Sleep debt in patients with 1 or more diabetic complications: β, −0.005; P=0.85 |
| Kim et al. (2013)88 | Cross-sectional study/Korea | Korean patients with diabetes (n=2,134) | Sleep duration was categorized as: <6, 6, 7, 8, and ≥9 hr/day; Reference: 7 hr/day |
Self-reported | 61.7±12.3, 49.9% | OR of high HbA1c (≥7.0%) Total with sleep <6 hr/day: OR, 1.15; 95% CI, 0.85–1.60 Total with sleep ≥9 hr/day: OR, 1.38; 95% CI, 0.93–2.03 Female with sleep <6 hr/day: OR, 1.46; 95% CI, 0.96–2.21 Female with sleep ≥9 hr/day: OR, 1.31; 95% CI, 0.75–2.27 Age <65 yr with sleep <6 hr/day: OR, 1.34; 95% CI, 0.86–2.09 Age <65 yr with sleep ≥9 hr/day: OR, 1.33; 95% CI, 0.84–2.41 |
| Ohkuma et al. (2013)67 | Cross-sectional study/Japan | Japanese patients with T2DM (n=4,870) | Sleep duration was categorized as: <4.5, 4.5–5.4, 5.5–6.4, 6.5–7.4, 7.5–8.4, and ≥8.5 hr/day | Self-reported | ≥20, 57% | Adjusted geometric means (95% CIs) of HbA1c Sleep <4.5 hr/day: 7.52 (7.38–7.67) Sleep 6.5–7.4 hr/day: 7.32 (7.28–7.37) Sleep ≥8.5 hr/day: 7.43 (7.34–7.52) P for quadratic trend: 0.004 |
| Wang et al. (2015)89 | Cross-sectional study/China | Patients with diabetes from the baseline survey of the REACTION Study (n=56,032) | Sleep duration was categorized as: <6, 6–7.9, 8–8.9, and ≥9 hr/night; Reference: 6–7.9 hr/night |
Self-reported | Sleep <6 hr/night: 61.2±8.8, 37%; Sleep ≥9 hr/night: 61.4±9.7, 38%; Reference: 60.5±8.8, 39% |
Poor glycemic control (HbA1c ≥7.0%) Sleep <6 hr/night: OR, 1.09; 95% CI, 0.99–1.21 Sleep ≥9 hr/night: OR, 1.11; 95% CI, 1.05–1.18 |
| Kong et al. (2017)90 | Cross-sectional study/Hong Kong | Hong Kong Chinese patients with T2DM (n=3,508) | Sleep duration: the period between bedtime and wake-up time on weekdays and weekends | Self-reported | 53.9±8.7, 59% | Sleep duration difference between weekdays and weekends is curvilinearly associated with both HbA1c and FPG. One hour more sleep during weekends than weekdays was associated with a decrease in HbA1c (−0.13%; 95 % CI, −0.24 to −0.02). |
Values are presented as range, mean±standard deviation, or mean (range).
RR, relative risk; CI, confidence interval; HR, hazard ratio; OR, odds ratio; NS, not specified; BMI, body mass index; WC, waist circumference; T2DM, type 2 diabetes mellitus; PSG, polysomnography; IGT, impaired glucose tolerance; FPG, fasting plasma glucose.