Table 4. Stepwise multiple regression models for CTLFA in males with and without VO100.
| Males with VO100 | Males without VO100 (n = 75) | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| (n = 113) | Model A | Model B | |||||||
| Variables | β | R2, % | P value | β | R2, % | P value | β | R2, % | P value |
| Age | 0.26 | 11.6 | 0.003 | − | − | − | − | − | − |
| BMI | -0.33 | 17.3 | <0.001 | -0.29 | 16.5 | 0.004 | -0.31 | 17.9 | 0.003 |
| %T<90 | − | − | − | -0.31 | 15.1 | <0.001 | … | … | … |
| 4%ODI | − | − | − | … | … | … | -0.22 | 8.8 | 0.013 |
| VFA | -0.21 | 6.4 | 0.009 | − | − | − | − | − | − |
| Triglycerides | -0.17 | 5.1 | 0.031 | -0.21 | 10.1 | 0.022 | -0.23 | 11.0 | 0.018 |
| HOMA-IR | − | − | − | -0.26 | 14.4 | 0.005 | -0.26 | 13.9 | 0.011 |
| Cumulative R 2 | … | 40.4 | … | … | 56.0 | … | … | 51.5 | … |
Variables entered into the stepwise regression analyses were selected from age, BMI, neck circumference, waist circumference, systolic and diastolic blood pressures, alcohol intake, use of lipid-lowering agents, current smoking, VFA, SFA, AHI, 4%ODI, %T<90, lowest SpO2, arousal index, REM sleep, AHI during REM, supine sleep time, AHI in supine position, Epworth sleepiness scale score, CRP, triglycerides, HDL-cholesterol, LDL-cholesterol, fasting plasma glucose, and HOMA-IR when yielding a P-value <0.10 by univariate analysis; %T<90 (Model A) and 4%ODI (Model B) were entered into the analyses separately for their strong collinearity; only variables left in one or more of the models are shown in this table. Minus sign means the variable was not selected through univariate or stepwise selection procedures. CTLFA is negatively correlated with liver fat accumulation.
Abbreviations: VO100, visceral obesity (VFA ≥100 cm2); β = standard regression coefficient; R2 = coefficient of determination; BMI, body mass index; %T<90, percentage of time spent with SpO2 below 90% to total sleep time; ODI, oxygen desaturation index; VFA, visceral fat accumulation; HOMA-IR, homeostasis model assessment index of insulin resistance.