Table 2.
Association between baseline sex-specific SMI tertiles and incidence of metabolic syndrome (Cox model) (N = 14,830)
| Lowest tertile (n = 4943) |
Middle tertile (n = 4944) |
Highest tertile (n = 4943) |
P for trend | |||||
|---|---|---|---|---|---|---|---|---|
| Referent | HR | 95% CI | P value | HR | 95% CI | P value | ||
| Model 1 | 1 | 0.56 | 0.52, 0.61 | < 0.001 | 0.26 | 0.24, 0.29 | < 0.001 | < 0.001 |
| Model 2 | 1 | 0.58 | 0.54, 0.63 | < 0.001 | 0.28 | 0.25, 0.31 | < 0.001 | < 0.001 |
| Model 3 | 1 | 0.91 | 0.83, 0.99 | 0.026 | 0.63 | 0.56, 0.70 | < 0.001 | < 0.001 |
| Model 4 | 1 | 0.88 | 0.81, 0.97 | 0.006 | 0.60 | 0.54, 0.68 | < 0.001 | < 0.001 |
| Subgroup analysesa | ||||||||
| Sex | P for interaction = 0.923 | |||||||
| Men (n = 8476) | 1 | 0.91 | 0.82, 1.01 | 0.088 | 0.65 | 0.57, 0.75 | < 0.001 | < 0.001 |
| Women (n = 6354) | 1 | 0.87 | 0.73, 1.03 | 0.099 | 0.56 | 0.44, 0.70 | < 0.001 | < 0.001 |
| Family history of diabetes | P for interaction = 0.954 | |||||||
| Absence (n = 13,279) | 1 | 0.91 | 0.83, 0.99 | 0.037 | 0.62 | 0.55, 0.70 | < 0.001 | < 0.001 |
| Presence (n = 1551) | 1 | 0.81 | 0.61, 1.08 | 0.144 | 0.47 | 0.31, 0.70 | < 0.001 | 0.001 |
| Smoking status | P for interaction = 0.314 | |||||||
| Never (n = 8278) | 1 | 0.86 | 0.75, 0.98 | 0.022 | 0.54 | 0.44, 0.65 | < 0.001 | < 0.001 |
| Past (n = 4078) | 1 | 0.85 | 0.73, 0.99 | 0.039 | 0.63 | 0.52, 0.78 | < 0.001 | < 0.001 |
| Present (n = 2474) | 1 | 0.95 | 0.80, 1.14 | 0.603 | 0.73 | 0.57, 0.92 | 0.009 | 0.023 |
| Exercise | P for interaction = 0.325 | |||||||
| Never (n = 12,593) | 1 | 0.87 | 0.79, 0.96 | 0.005 | 0.62 | 0.54, 0.70 | < 0.001 | < 0.001 |
| Regular (n = 2237) | 1 | 0.99 | 0.79, 1.24 | 0.940 | 0.50 | 0.35, 0.70 | < 0.001 | < 0.001 |
| Obesity | P for interaction < 0.001 | |||||||
| Absence (n = 10,925) | 1 | 0.77 | 0.68, 0.87 | < 0.001 | 0.56 | 0.47, 0.66 | < 0.001 | < 0.001 |
| Presence (n = 3905) | 1 | 1.04 | 0.91, 1.18 | 0.568 | 0.97 | 0.85, 1.12 | 0.698 | 0.603 |
| P for interaction = 0.062 | ||||||||
| Age ≤ 50 (n = 8017) | 1 | 0.92 | 0.81, 1.05 | 0.232 | 0.60 | 0.50, 0.72 | < 0.001 | < 0.001 |
| Age > 50 (n = 6813) | 1 | 0.83 | 0.74, 0.94 | 0.002 | 0.63 | 0.54, 0.73 | < 0.001 | < 0.001 |
| IFG | P for interaction = 0.007 | |||||||
| Absence (n = 13,129) | 1 | 0.87 | 0.79, 0.96 | 0.006 | 0.59 | 0.51, 0.67 | < 0.001 | < 0.001 |
| Presence (n = 1701) | 1 | 0.91 | 0.74, 1.13 | 0.399 | 0.58 | 0.44, 0.77 | < 0.001 | < 0.001 |
| P for interaction = 0.019 | ||||||||
| HOMA-IRb ≤ 2.5 (n = 7957) | 1 | 0.94 | 0.82, 1.07 | 0.344 | 0.71 | 0.59, 0.84 | < 0.001 | < 0.001 |
| HOMA-IR > 2.5 (n = 2006) | 1 | 1.14 | 0.95, 1.37 | 0.158 | 0.80 | 0.64, 1.00 | 0.053 | 0.002 |
Model 1: crude
Model 2: Model 1 + further adjusted for age
Model 3: Model 2 + further adjusted for BMI
Model 4: Model 3 + further adjusted for family history of diabetes, smoking status, regular exercise, eGFR, and CRP
BMI body mass index, CI confidence interval, CRP C-reactive protein, eGFR estimated glomerular filtration rate, HOMA-IR homeostasis model assessment of insulin resistance, HR hazard ratio, IFG impaired fasting glucose, SMI skeletal muscle mass index
aSubgroup analyses were adjusted for Model 4
bA total of 9963 subjects were analyzed due to missing HOMA-IR values