Table 1.
General characteristics of ONTIME population.
| Morning Chronotype (Mean ± SEM) n = 1,110 | Evening Chronotype (Mean ± SEM) n = 1,016 | P-value | P-trend | |
|---|---|---|---|---|
| Age (y) | 42.97 ± 12.67a | 36.17 ± 12.68a | <0.001 | <0.001 |
| %Women, n (%) | 902 (81.3) | 820 (80.7) | 0.746 | — |
| BMI (kg/m2) | 30.99 ± 0.16 | 31.31 ± 0.16 | 0.157 | 0.032 |
| Body fat (%) | 37.03 ± 0.19 | 36.98 ± 0.19 | 0.849 | 0.543 |
| Metabolic syndrome and insulin resistance | ||||
| Waist (cm) | 102.21 ± 0.40 | 102.52 ± 0.42 | 0.592 | 0.236 |
| Fasting glucose (mg/dl) | 85.09 ± 0.45 | 85.34 ± 0.48 | 0.714 | 0.738 |
| Triglycerides (mg/dl)* | 100.63 ± 1.71 | 105.00 ± 1.79 | 0.009 | 0.006 |
| HDL-c (mg/dl) | 57.07 ± 0.46 | 55.57 ± 0.48 | 0.026 | 0.001 |
| Systolic Pressure (mmHg) | 11.63 ± 0.04 | 11.64 ± 0.05 | 0.901 | 0.268 |
| Diastolic pressure (mmHg) | 7.25 ± 0.03 | 7.22 ± 0.03 | 0.563 | 0.650 |
| MetS Score* | 2.06 ± 0.04 | 2.16 ± 0.04 | 0.011 | 0.050 |
| Insulin (µUI/ml)* | 7.40 ± 0.22 | 7.62 ± 0.23 | 0.112 | <0.001 |
| HOMA-IR* | 1.61 ± 0.05 | 1.68 ± 0.06 | 0.360 | 0.002 |
Chronotype was dichotomized into “more morning” (Morning type) and “more evening” (Evening type) based on the median ME score of the total population (<53, more evening; ≥53, more morning).
Abbreviations: BMI, Body mass index; MetS, Metabolic Syndrome; HDL-C, High Density Lipoprotein – Cholesterol; VLDL-C, Very Low Density Lipoprotein-Cholesterol; HOMA-IR, Homeostatic Model Assessment – Insulin Resistance.
Adjusted by sex, age, clinic site and number study.
aM ± SD.
*Values were logarithmically transformed.
P-value refers to association between morning and evening chronotype and exposures of interest. P-trend refers to the continuous association between the ME score and exposures of interest.