Table 3.
Association Between Plasma Leptin Level and Diabetes Mellitus, by Body Mass Index in NHANES III (1988–1994)
| Plasma leptin levela | Number at risk | Diabetes cases | Multivariable-adjusted odds ratio (95% confidence interval)b |
|---|---|---|---|
| Normal weight (BMI <25 kg/m2) | |||
| Quartile 1 | 994 | 21 | 1 (referent) |
| Quartile 2 | 776 | 25 | 0.97 (0.40–2.35) |
| Quartile 3 | 348 | 12 | 1.09 (0.48–2.49) |
| Quartile 4 | 69 | 3 | 1.06 (0.34–3.30) |
| P trend | 0.8071 | ||
| Overweight (BMI 25–29 kg/m2) | |||
| Quartile 1 | 168 | 11 | 1 (referent) |
| Quartile 2 | 499 | 45 | 0.95 (0.31–2.91) |
| Quartile 3 | 848 | 58 | 0.61 (0.19–1.98) |
| Quartile 4 | 463 | 40 | 0.59 (0.18–1.96) |
| P trend | 0.2143 | ||
| Overweight/obese (BMI ≥30 kg/m2) | |||
| Quartile 1 | 24 | 3 | 1 (referent) |
| Quartile 2 | 70 | 13 | 0.74 (0.10–5.45) |
| Quartile 3 | 337 | 45 | 0.790 (0.18–3.52) |
| Quartile 4 | 1,003 | 119 | 0.96 (0.39–0.36) |
| P trend | 0.7776 | ||
Plasma leptin quartiles in women: quartile 1 (<7.68 fg/L), quartile 2 (7.68–13.18 fg/L), quartile 3 (13.19–21.70 fg/L), quartile 4 (>21.70 fg/L). In men: quartile 1 (<2.64 fg/L), quartile 2 (2.64–4.36 fg/L), quartile 3 (4.37–7.12 fg/L), quartile 4 (>7.12 fg/L).
Adjusted for age (years), sex (men, women), race-ethnicity (non-Hispanic whites, non-Hispanic blacks, Mexican Americans, others), education categories (<high school, high school, >high school), smoking (never, former, current), alcohol intake (never, former, current), hypertension (absent, present), serum total cholesterol (mg/dL), and high sensitivity C-reactive protein (mg/L).
NHANES III, Third National Health and Nutrition Examination Survey; BMI, body mass index.