Table 2:
Selected studies investigating associations between sleep or food behaviors and metabolic syndrome or NAFLD
| Article | Study Type | Population | Control | Comparator | Key findings |
|---|---|---|---|---|---|
| Selected studies investigating associations between sleep disturbance or time-restricted feeding and metabolic syndrome | |||||
| Spiegel 1999 185 | Observation study | Healthy volunteers (n=11) | n/a | Sleep deprivation | • Sleep-deprivation reduced glucose tolerance and evening cortisol concentrations |
| Wang 2014 186 | Meta-analysis of 13 observational studies | Workers exposed to night shift (n=2,286) | Day shift work | Night shift workers | • Higher risk of metabolic syndrome in workers exposed to night shift (OR 1.5-1.6) |
| Vyas 2012 187 | Meta-analysis of 9 case control studies, 11 prospective cohort studies, and 6 retrospective cohort studies | Workers exposed to shift work (n=2,000,000) | Shit workers | Day workers | • Shift work is associated with an increased risk of myocardial infarction and coronary events (OR 1.23) |
| Karlsson 2001 188 | Observational study | Working adults (n=27,485) | Day workers | Shift workers | • OR of obesity ~1.3 higher in shift workers compared to day workers • Dyslipidemia clustered with shit workers compared to day workers (p<0.05) |
| Wilkinson 2019 189 | Paired-sample trial | Patients with metabolic syndrome (n=19) | 2-week baseline of eating interval of ≥14 h per day | 12-weeks of time-restricted eating (TRE) to a 10-hour interval | • After 12-weeks of TRF, there was a 3% reduction in weight (p=0.0003), 11% reduction in LDL-C (=0.016), and 8% reduction in estimated calorie intake (p=0.007) , but no difference in insulin resistance (p=0.107) |
| Selected studies investigating associations between sleep disturbances and/or shiftwork and NAFLD | |||||
| Hsieh 2011 190 | Observational | All-male Tokyo office workers (n=8157) | Sleep >7hours | Sleep <7 hours | • Rates of NAFLD were higher in patients who slept <7 hours (OR 1.23) |
| Kim 2013 191 | Observational | Workers and spouses at a Korean conglomerate (n= 69,463) | Sleep >5 hours | Sleep <5 hours | • Rates of NAFLD were higher among women (but not men) who slept 5 hours (OR 1.59 in women; 1.03 in men) |
| Imaizumi 2015 192 | Observational studies | General patients (n=3986) | Sleep duration 6 to ≤7 h | Sleep duration ≤ 6 hours | • Rates of NAFLD were higher among women (but not men) who slept ≤ 6hours (OR 1.44 in women, 0.98 in men) |
| Bernsmeier 2015 193 | Case-control study | Cohort in Basel (n= 68) | Healthy volunteers (n=22) | Biopsy-proven NAFLD group (n=46) | • NAFLD group had shorter sleep duration and poorer sleep quality compared to controls (p<0.01). In NAFLD patients, but not in controls, daytime sleepiness was correlated with higher liver enzymes, and insulin resistance. • NAFLD patients with fibrosis had stronger correlation to daytime sleepiness (p=0.02) |
| Marin-Alejandre 2019 194 | Cross-sectional study | Fatty Liver in Obesity (FLiO) participants in Spain (n=134) | Normal weight non-NAFLD patients (n=40) | Overweight patients with NAFLD (n=94) | • Adjusted odds of sleep disturbance was higher in NAFLD group (OR 1.59) • Regression models predicted ~20% of variability in liver stiffness could be attributed to sleep disturbance or sleep quality |
| Liu 2016 195 | Cohort study | Patients who developed NAFLD after 5 years of follow-up (n=2197) | Sleep duration 7-8 hours | Sleep duration 8-9 hours; sleep duration >9 hours | • Adjusted odds of NAFLD was higher with longer sleep durations (OR 1.21 for 8-9 hours group 1.31 in >9 hours group) |
| Balakrishnan 2017 196 | Observational study | General workers (n=8159) | Non-shift workers | Shift workers | • Adjusted odds of NAFLD did not differ between shift-workers and non-shift workers (OR 1.11) |
| Katsagoni 2018 197 | Randomized controlled trial | Patients with NAFLD (n=63) | Controls with NAFLD without intervention | Mediterranean lifestyle (adequate sleep and activity) | • Mediterranean lifestyle was associated with a decrease in liver stiffness (adjusted OR 0.78) |
| Katsagoni 2017198 | Case Control Study | Patients with NAFLD and controls (n=155) | Controls without NAFLD (n=55) | Patients with NAFLD (n=100) | • Optimal sleep duration was inversely associated with NAFLD presence (OR = 0.38, p=.0.05) |
| Selected studies investigating link between OSA and NAFLD | |||||
| Musso 2013 199 | Meta-analysis of 18 cross-sectional studies | 18 cross-sectional studies (n=2, 183) of patients with OSA who were assessed for NAFLD | OSA patients without NAFLD | OSA patients with NAFLD | • OSA was associated with NASH (OR 2.37), and advanced fibrosis (OR 2.3) in biopsy proven NAFLD patients |
| Pamidi 2012200 | Observational | Healthy and young OSA patients | Control subjects without OSA (n=20) | Patients with OSA (n=12) | • OSA was associated with a 27% lower insulin sensitivity compared to controls |