Table 2. Characteristics of the study participants (n = 4683).
| Variables | Mean ± standard deviation or n (%) | P value | |||||
| Men (n = 2168) | Women (n = 2515) | ||||||
| Age, years | 74.0±5.3 | 73.9±5.5 | 0.800 | ||||
| Age group, n (%) | 0.398 | ||||||
| 65–69 | 481(22.2) | 588(23.4) | |||||
| 70–74 | 727(33.5) | 847(33.7) | |||||
| 75–79 | 615(28.4) | 658(26.2) | |||||
| 80–84 | 297(13.7) | 354(14.1) | |||||
| 85 or over | 48(2.2) | 68(2.7) | |||||
| Geographic area, n (%) | <0.001 | ||||||
| NANGAI | 434(20.0) | 592(23.5) | |||||
| ITABASHI02 | 448(20.7) | 385(15.3) | |||||
| YOITA | 250(11.5) | 352(14.0) | |||||
| KUSATSU | 255(11.8) | 339(13.5) | |||||
| HATOYAMA | 425(19.6) | 309(12.3) | |||||
| ITABASHI11 | 356(16.4) | 538(21.4) | |||||
| Height, cm | 160.7±6.3 | 147.6±6.2 | <0.001 | ||||
| Weight, kg | 59.9±9.4 | 50.5±8.4 | <0.001 | ||||
| Body mass index, kg/m2 | 23.2±3.0 | 23.2±3.5 | 0.917 | ||||
| Chronic disease, n (%) | |||||||
| Hypertension | 981(45.3) | 1216(48.4) | 0.033 | ||||
| Stroke | 179(8.3) | 104(4.1) | <0.001 | ||||
| Heart disease | 459(21.3) | 420(16.8) | <0.001 | ||||
| Diabetes mellitus | 300(13.9) | 232(9.2) | <0.001 | ||||
| Self-rated health, n (%) | <0.001 | ||||||
| Excellent to good | 1777(82.0) | 1997(79.4) | |||||
| Fair to poor | 389(18.0) | 518(20.6) | |||||
| Alcohol drinking status, n (%) | <0.001 | ||||||
| Current | 1426(65.9) | 581(23.1) | |||||
| Past | 245(11.3) | 137(5.4) | |||||
| Never | 494(22.8) | 1796(71.4) | |||||
| Smoking status, n (%) | <0.001 | ||||||
| Current | 526(24.3) | 107(4.3) | |||||
| Past | 1048(48.4) | 130(5.2) | |||||
| Never | 590(27.3) | 2276(90.6) | |||||
| TMIG-IC, score (0–13) | 12.0±1.6 | 12.0±1.7 | 0.527 | ||||
| Instrumental self-maintenance (0–5) | 4.8±0.6 | 4.9±0.6 | 0.002 | ||||
| Intellectual activity (0–4) | 3.7±0.7 | 3.5±0.9 | <0.001 | ||||
| Social role (0–4) | 3.5±0.8 | 3.7±0.7 | <0.001 | ||||
| Physical performance measures | |||||||
| Hand-grip strength, kg | 31.7±6.7 | 20.4±5.0 | <0.001 | ||||
| One-legged stance with eyes open, s | 39.3±23.0 | 36.8±23.4 | 0.003 | ||||
| Usual gait speed, m/s | 1.29±0.25 | 1.25±0.27 | <0.001 | ||||
| Usual gait step length, cm | 67.7±10.0 | 60.8±10.0 | <0.001 | ||||
| Maximum gait speed, m/s | 1.94±0.38 | 1.73±0.36 | <0.001 | ||||
| Maximum gait step length, cm | 82.3±11.6 | 69.7±10.8 | <0.001 | ||||
NANGAI = Nangai Cohort Study; ITABASHI02 = Itabashi Cohort Study 2002; YOITA = Yoita Longitudinal Study; KUSATSU = Kusatsu Longitudinal Study; HATOYAMA = Hatoyama Cohort Study; ITABASHI11 = Itabashi Cohort Study 2011; TMIG-IC = Tokyo Metropolitan Institute of Gerontology Index of Competence.