Table 2. Secular trends in body mass index, blood pressure, and serum lipids.
| Regression coefficient (95% CI) | ||
| Boys (n = 7663) | Girls (n = 7209) | |
| BMI (kg/m2) | ||
| 95th percentile | 0.087 (0.039 to 0.135)a | 0.010 (−0.045 to 0.066) |
| 50th percentile | 0.006 (−0.010 to 0.023) | −0.012 (−0.023 to −0.001)a |
| 5th percentile | −0.017 (−0.030 to −0.004)a | −0.025 (−0.039 to −0.011)a |
| SBP (mm Hg) | ||
| 95th percentile | −0.524 (−0.815 to −0.234)a | −0.401 (−0.610 to −0.192)a |
| 50th percentile | −0.484 (−0.713 to −0.256)a | −0.506 (−0.710 to −0.301)a |
| 5th percentile | −0.565 (−0.780 to −0.350)a | −0.507 (−0.790 to −0.223)a |
| DBP (mm Hg) | ||
| 95th percentile | −0.141 (−0.328 to 0.047) | −0.049 (−0.196 to 0.097) |
| 50th percentile | −0.326 (−0.489 to −0.163)a | −0.211 (−0.406 to −0.016)a |
| 5th percentile | −0.375 (−0.624 to −0.126)a | −0.365 (−0.606 to −0.125)a |
| TC (mg/dL) | ||
| 95th percentile | 0.305 (−0.248 to 0.859) | 0.030 (−0.601 to 0.662) |
| 50th percentile | 0.003 (−0.334 to 0.341) | 0.031 (−0.417 to 0.479) |
| 5th percentile | 0.090 (−0.247 to 0.427) | −0.070 (−0.441 to 0.302) |
| Non-HDL-C (mg/dL) | ||
| 95th percentile | 0.348 (−0.182 to 0.878) | −0.030 (−0.625 to 0.566) |
| 50th percentile | 0.004 (−0.356 to 0.365) | −0.159 (−0.524 to 0.206) |
| 5th percentile | 0.118 (−0.278 to 0.515) | 0.027 (−0.402 to 0.456) |
| HDL-C (mg/dL) | ||
| 95th percentile | −0.118 (−0.595 to 0.359) | 0.004 (−0.483 to 0.490) |
| 50th percentile | 0.121 (−0.208 to 0.451) | 0.196 (−0.089 to 0.480) |
| 5th percentile | 0.060 (−0.156 to 0.277) | 0.289 (0.047 to 0.532)a |
Regression analysis was performed to evaluate secular trends.
The independent variable was the year of the study; the dependent variables were the 5th, 50th, and 95th percentiles of each variable.
The weighted least-squares method was used to adjust the sample size for the year.
CI, confidence interval; BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; TC, total cholesterol; Non-HDL-C, non-high-density lipoprotein cholesterol; HDL-C, high-density lipoprotein cholesterol.
aP < 0.05.