Table 1. Baseline characteristics of participants by quartile of BMI at age 20.
| Time, Measurement | Quartile of BMI at age 20a |
Regression per 5 kg m−2 |
|||||
|---|---|---|---|---|---|---|---|
| 1st | 2nd | 3rd | 4th | MD or OR | 95% CI | N | |
| aMeasured at age 20: | |||||||
| bBMI (kg m−2) | 18.9 | 20.7 | 22.0 | 24.4 | 5.00 | (5.00, 5.00) | 11,233 |
| bAge (years) | 19.6 | 19.7 | 19.8 | 20.0 | 0.34 | (0.26, 0.41) | 11,233 |
| bHeight (cm) | 172.1 | 172.6 | 172.6 | 171.3 | −0.87 | (−1.19, −0.55) | 11,233 |
| bWeight (kg) | 56.0 | 61.7 | 65.6 | 71.8 | 14.0 | (13.8, 14.3) | 11,233 |
| bPulse rate (bpm) | 77.2 | 76.0 | 75.5 | 75.7 | −0.9 | (−1.3, −0.4) | 10,876 |
| bNumber of siblings | 1.51 | 1.66 | 1.70 | 1.67 | 0.08 | (0.02, 0.15) | 11,230 |
| cFemale (%) | 26.6 | 22.3 | 20.0 | 23.1 | 0.84 | (0.76, 0.93) | 11,233 |
| cFirst-born (%) | 59.6 | 55.6 | 54.8 | 55.1 | 0.89 | (0.82, 0.97) | 11,233 |
| cHigh paternal SEP (%) | 56.5 | 58.0 | 56.7 | 57.6 | 1.03 | (0.94, 1.12) | 10,829 |
| cSmokers (%) | 28.8 | 29.9 | 27.4 | 29.2 | 1.00 | (0.91, 1.10) | 10,768 |
| dMeasured in 2001: | |||||||
| bBMI (kg m−2) | 23.9 | 24.9 | 25.5 | 27.2 | 2.81 | (2.62, 3.00) | 4,841 |
| bAge (years) | 63.1 | 62.8 | 62.9 | 62.6 | −0.46 | (−0.89, −0.02) | 4,841 |
| bHeight (cm) | 172.5 | 173.5 | 174.0 | 172.6 | 0.12 | (−0.41, 0.66) | 4,841 |
| bWeight (kg) | 71.3 | 75.2 | 77.4 | 81.2 | 8.5 | (7.7, 9.2) | 4,841 |
| cSmokers (%) | 7.5 | 9.1 | 10.5 | 10.6 | 1.29 | (1.05, 1.58) | 4,789 |
| c,eStarted smoking (%) | 33.3 | 32.0 | 36.4 | 38.4 | 1.31 | (1.12, 1.52) | 3,424 |
| c,eStopped smoking (%) | 86.8 | 79.2 | 80.7 | 78.5 | 0.74 | (0.53, 1.01) | 1,186 |
BMI: body mass index, CI: confidence interval, SEP: socioeconomic position, MD: mean difference, OR, odds ratio.
aMeasured age 16–25.
bInterval-scale variables are summarised as means within each quartile of BMI and mean differences per 5 kg m−2 of BMI from unadjusted linear regression are presented.
cBinary variables are summarised as percentages within each quartile of BMI and odds ratios per 5 kg m−2 of BMI from unadjusted logistic regression are presented.
dMeasured 2000–2002 and BMI standardised to age 63.
eThe analysis of smoking uptake was restricted to non-smokers at age 20 and the analysis of smoking cessation was restricted to smokers at age 20.