Table 2. Background characteristics according to BMI categories in women (NIPPON DATA2010).
| BMI, kg/m2 | P valuea | |||||||||
| ≤18.5 | 18.6–24.9 | 25–29.9 | ≥30 | |||||||
| Adult women (20–64 years) | ||||||||||
| n (%) | 92 | (11.1) | 571 | (68.8) | 141 | (17.0) | 26 | (3.1) | ||
| Age, years | 42.4 | (13.7)** | 48.0 | (11.2) | 52.1 | (10.8)** | 50.0 | (12.7) | <0.01 | |
| BMI, kg/m2 | 17.4 | (0.7) | 21.5 | (1.8) | 26.8 | (1.3) | 33.2 | (2.6) | <0.01 | |
| Number of household members, n (%) | 1 | 2 | (2.2) | 43 | (7.5) | 11 | (7.8) | 1 | (3.9) | |
| 2 | 23 | (25.0) | 172 | (30.1) | 43 | (30.5) | 9 | (34.6) | 0.39 | |
| ≥3 | 67 | (72.8) | 356 | (62.4) | 87 | (61.7) | 16 | (61.5) | ||
| Education level, n (%) | Higher education | 43 | (46.7) | 273 | (47.8) | 42 | (29.8) | 6 | (23.1) | <0.01 |
| Lower education | 49 | (53.3) | 298 | (52.2) | 99 | (70.2) | 20 | (76.9) | ||
| Marital and living statuses, n (%) | Married | 63 | (68.5) | 455 | (79.7) | 114 | (80.9) | 19 | (73.1) | 0.18 |
| Single, not living alone | 27 | (29.3) | 83 | (14.5) | 21 | (14.9) | 7 | (26.9) | ||
| Single, living alone | 2 | (2.2) | 33 | (5.8) | 6 | (4.3) | — | |||
| Occupational status, n (%) | Employed | 51 | (55.4) | 344 | (60.2) | 99 | (70.2) | 17 | (76.9) | 0.18 |
| Unemployed | 41 | (44.6) | 227 | (39.8) | 42 | (29.8) | 9 | (23.1) | ||
| Household income, JPY, n (%) | ≥6,000,000 | 35 | (38.0) | 172 | (30.1) | 25 | (17.7) | 4 | (15.4) | |
| 2,000,000–6,000,000 | 43 | (46.7) | 331 | (58.0) | 92 | (65.3) | 13 | (50.0) | <0.01 | |
| <2,000,000 | 14 | (15.2) | 68 | (11.9) | 24 | (17.0) | 9 | (34.6) | ||
| Elderly women (≥65 years) | ||||||||||
| n (%) | 35 | (6.0) | 387 | (66.7) | 133 | (22.9) | 25 | (4.3) | ||
| Age, years | 74.5 | (6.7) | 73 | (5.8) | 73.1 | (5.8) | 74.6 | (6.2) | 0.33 | |
| BMI, kg/m2 | 17.3 | (1.0) | 22.1 | (1.8) | 26.7 | (1.3) | 31.5 | (1.7) | <0.01 | |
| Number of household members, n (%) | 1 | 7 | (20.0) | 101 | (26.1) | 36 | (27.1) | 11 | (44.0) | |
| 2 | 14 | (40.0) | 186 | (48.1) | 62 | (46.6) | 6 | (24.0) | 0.02 | |
| ≥3 | 14 | (40.0) | 100 | (25.8) | 35 | (26.3) | 8 | (32.0) | ||
| Education level, n (%) | Higher education | 5 | (14.3) | 65 | (16.8) | 29 | (21.8) | 4 | (16.0) | 0.43 |
| Lower education | 30 | (85.7) | 322 | (83.2) | 104 | (78.2) | 21 | (84.0) | ||
| Marital and living statuses, n (%) | Married | 22 | (62.9) | 258 | (66.7) | 82 | (61.7) | 10 | (40.0) | 0.18 |
| Single, not living alone | 7 | (20.0) | 51 | (13.2) | 20 | (15.0) | 6 | (24.0) | ||
| Single, living alone | 6 | (17.1) | 78 | (20.2) | 31 | (23.3) | 9 | (36.0) | ||
| Occupational status, n (%) | Employed | 5 | (8.6) | 65 | (12.4) | 29 | (9.8) | 4 | (4.0) | 0.56 |
| Unemployed | 30 | (91.4) | 322 | (87.6) | 104 | (90.2) | 21 | (96.0) | ||
| Household income, JPY, n (%) | ≥6,000,000 | 6 | (17.1) | 40 | (10.3) | 9 | (6.8) | — | ||
| 2,000,000–6,000,000 | 20 | (57.1) | 217 | (56.1) | 71 | (53.4) | 14 | (56.0) | 0.20 | |
| <2,000,000 | 9 | (25.7) | 130 | (33.6) | 53 | (39.8) | 11 | (44.0) | ||
BMI, body mass index; JPY, Japanese yen; SD, standard deviation.
Data are presented as mean (SD) or as a number (%).
aP values were calculated using a one-way analysis of variance for continuous variables or the chi-squared test for categorical variables.
*P < 0.05; **P < 0.01, significantly different from the normal BMI group using Dunnett’s test.