Table 4. Baseline characteristics by BMIa category in 8477 women aged 65–79 years.
| BMI (kg/m2) | P valueb | |||||||
| <18.5 | 18.5–20.9 | 21.0–22.9 | 23.0–24.9 | 25.0–27.4 | 27.5–29.9 | ≥30.0 | ||
| No. of subjects | 503 | 1383 | 1977 | 1906 | 1666 | 702 | 340 | |
| Mean age (years) (SDa) | 72.0 (4.3) | 70.9 (4.3) | 70.4 (4.2) | 70.0 (4.0) | 70.0 (4.0) | 70.0 (4.1) | 70.0 (4.0) | <0.0001 |
| Mean weight (kg) (SD) | 39.6 (4.5) | 44.6 (3.7) | 48.8 (3.7) | 53.6 (4.0) | 58.1 (4.7) | 62.5 (5.2) | 68.7 (12.0) | <0.0001 |
| Mean height (cm) (SD) | 151.9 (8.8) | 149.5 (5.8) | 148.8 (5.3) | 149.3 (5.3) | 149.0 (5.6) | 147.8 (5.9) | 144.6 (10.3) | <0.0001 |
| Mean BMI (kg/m2) (SD) | 17.2 (1.2) | 19.9 (0.7) | 22.0 (0.6) | 24.0 (0.6) | 26.1 (0.7) | 28.6 (0.7) | 33.0 (5.6) | <0.0001 |
| Weight change since age 20 years (%) | ||||||||
| ≤−10.0 kg | 41.9 | 22.7 | 12.0 | 4.5 | 3.3 | 1.5 | 1.3 | <0.0001 |
| −9.9 to −5.0 kg | 33.3 | 35.1 | 25.4 | 16.1 | 8.7 | 4.5 | 2.6 | |
| −4.9 to +4.9 kg | 22.7 | 36.9 | 46.3 | 39.0 | 21.6 | 15.3 | 6.2 | |
| +5.0 to +9.9 kg | 1.8 | 4.9 | 12.7 | 26.6 | 29.9 | 22.7 | 13.1 | |
| ≥+10.0 kg | 0.2 | 0.3 | 3.6 | 13.8 | 36.5 | 56.0 | 76.8 | |
| Education (%) | ||||||||
| Junior high school or less | 65.7 | 68.8 | 68.4 | 67.1 | 72.6 | 75.2 | 82.1 | <0.0001 |
| High school | 28.6 | 26.4 | 25.0 | 26.2 | 22.1 | 19.2 | 14.7 | |
| College/university or higher | 5.7 | 4.8 | 6.6 | 6.7 | 5.2 | 5.6 | 3.3 | |
| Marital status (%) | ||||||||
| Married | 59.8 | 61.7 | 62.9 | 62.8 | 63.9 | 65.5 | 62.0 | NSa |
| Unmarried | 40.2 | 38.4 | 37.1 | 37.2 | 36.1 | 34.5 | 38.0 | |
| Smoking status (%) | ||||||||
| Never smoker | 84.1 | 90.0 | 90.0 | 91.1 | 92.3 | 91.4 | 89.8 | 0.0016 |
| Past smoker | 4.1 | 2.6 | 3.0 | 3.6 | 2.9 | 3.0 | 5.1 | |
| Current smoker, 1–19 cigarettes/day | 10.5 | 6.3 | 6.1 | 4.8 | 3.9 | 4.7 | 3.9 | |
| Current smoker, ≥20 cigarettes/day | 1.3 | 1.1 | 1.0 | 0.5 | 0.8 | 1.0 | 1.2 | |
| Alcohol drinking (%) | ||||||||
| Never drinker | 82.0 | 81.1 | 81.8 | 81.4 | 82.0 | 78.3 | 80.4 | NS |
| Past drinker | 4.6 | 4.5 | 4.9 | 4.4 | 3.4 | 4.8 | 5.8 | |
| Current drinker | 13.5 | 14.4 | 13.3 | 14.2 | 14.6 | 16.9 | 13.8 | |
| Time spent walking (%) | ||||||||
| ≥1 hour/day | 34.3 | 40.4 | 39.8 | 38.7 | 35.5 | 34.7 | 28.5 | 0.0002 |
| <1 hour/day | 65.7 | 59.6 | 60.2 | 61.3 | 64.5 | 65.3 | 71.5 | |
| Sports and physical exercise (%) | ||||||||
| ≥5 hours/week | 4.6 | 8.4 | 6.9 | 9.2 | 8.5 | 7.2 | 9.7 | 0.0003 |
| 3–4 hours/week | 6.7 | 7.6 | 8.5 | 8.1 | 8.1 | 7.8 | 6.6 | |
| 1–2 hours/week | 12.7 | 14.9 | 19.3 | 19.4 | 18.2 | 18.1 | 13.1 | |
| <1 hour/week | 76.0 | 69.0 | 65.3 | 63.3 | 65.2 | 66.9 | 70.7 | |
| History of hypertension (%) | ||||||||
| Yes | 24.7 | 29.9 | 35.0 | 39.8 | 45.8 | 50.7 | 54.7 | <0.0001 |
| No | 75.4 | 70.1 | 65.0 | 60.2 | 54.2 | 49.3 | 45.3 | |
| History of diabetes (%) | ||||||||
| Yes | 5.8 | 6.1 | 8.7 | 7.5 | 8.2 | 9.0 | 12.9 | 0.0004 |
| No | 94.2 | 93.9 | 91.4 | 92.6 | 91.8 | 91.0 | 87.1 | |
| History of kidney disease (%) | ||||||||
| Yes | 4.4 | 4.3 | 4.5 | 4.0 | 5.0 | 4.4 | 2.1 | NS |
| No | 95.6 | 95.7 | 95.5 | 96.0 | 95.0 | 95.6 | 97.9 | |
| History of liver disease (%) | ||||||||
| Yes | 4.0 | 4.8 | 5.5 | 5.0 | 3.8 | 4.6 | 6.2 | NS |
| No | 96.0 | 95.2 | 94.5 | 95.0 | 96.2 | 95.4 | 93.8 | |
aBMI, body mass index; SD, standard deviation; NS, not significant.
bP values were calculated by using the chi-square test (for categorical variables) or ANOVA (for continuous variables).