Table 2. Hazard ratios of all-cause and cause-specific mortality according to number of teeth in the Takayama study.
| Variable | Number of teeth | ||||
| ≥20 | 10–19 | 0–9 | Per 1 tooth lost | P-valuea | |
| All causes | |||||
| Number of death | 367/6,174 | 274/2,478 | 457/2,621 | ||
| Age and sex adjustedb | 1 | 1.25 (1.07–1.47) | 1.31 (1.13–1.53) | 1.01 (1.01–1.02) | <0.001 |
| Multivariate adjustedc | 1 | 1.18 (1.01–1.39) | 1.19 (1.03–1.39) | 1.01 (1.00–1.01) | 0.01 |
| All cancer | |||||
| Number of death | 155/6,174 | 105/2,478 | 175/2,621 | ||
| Age and sex adjustedb | 1 | 1.27 (0.98–1.63) | 1.45 (1.15–1.84) | 1.02 (1.01–1.03) | 0.001 |
| Multivariate adjustedc | 1 | 1.18 (0.92–1.53) | 1.31 (1.03–1.67) | 1.01 (1.00–1.02) | 0.02 |
| Lung cancer | |||||
| Number of death | 32/6,174 | 27/2,478 | 54/2,621 | ||
| Age and sex adjustedb | 1 | 1.61 (0.95–2.71) | 2.19 (1.36–3.54) | 1.03 (1.02–1.05) | 0.001 |
| Multivariate adjustedc | 1 | 1.39 (0.82–2.34) | 1.75 (1.08–2.83) | 1.02 (1.00–1.04) | 0.03 |
| Upper gastrointestinal cancer | |||||
| Number of death | 31/6,174 | 25/2,478 | 22/2,621 | ||
| Age and sex adjustedb | 1 | 1.51 (0.90–2.66) | 0.95 (0.52–1.71) | 0.99 (0.97–1.02) | 0.70 |
| Multivariate adjustedc | 1 | 1.50 (0.87–2.60) | 0.88 (0.48–1.61) | 0.99 (0.97–1.02) | 0.50 |
| Orodigestive cancerd | |||||
| Number of death | 78/6,174 | 54/2,478 | 77/2,621 | ||
| Age and sex adjustedb | 1 | 1.27 (0.89–1.82) | 1.25 (0.88–1.76) | 1.01 (0.99–1.02) | 0.15 |
| Multivariate adjustedc | 1 | 1.22 (0.85–1.74) | 1.16 (0.82–1.65) | 1.01 (0.99–1.02) | 0.33 |
| All cancer other than lung cancer | |||||
| Number of death | 129/6,174 | 78/2,478 | 121/2,621 | ||
| Age and sex adjustedb | 1 | 1.18 (0.88–1.58) | 1.26 (0.96–1.66) | 1.01 (0.99–1.02) | 0.06 |
| Multivariate adjustedc | 1 | 1.13 (0.84–1.51) | 1.19 (0.90–1.58) | 1.01 (0.99–1.02) | 0.17 |
| CVD | |||||
| Number of death | 78/6,174 | 65/2,478 | 92/2,621 | ||
| Age and sex adjustedb | 1 | 1.22 (0.87–1.70) | 0.98 (0.71–1.36) | 1.00 (0.99–1.01) | 0.99 |
| Multivariate adjustedc | 1 | 1.18 (0.84–1.65) | 0.92 (0.67–1.28) | 1.00 (0.98–1.01) | 0.70 |
| Other causes | |||||
| Number of death | 129/6,174 | 97/2,478 | 185/2,621 | ||
| Age and sex adjustedb | 1 | 1.23 (0.94–1.61) | 1.42 (1.11–1.81) | 1.02 (1.01–1.03) | 0.002 |
| Multivariate adjustedc | 1 | 1.17 (0.89–1.53) | 1.27 (0.99–1.62) | 1.01 (1.00–1.02) | 0.04 |
| COPD-related | |||||
| Number of death | 3/6,174 | 5/2,478 | 15/2,621 | ||
| Age and sex adjustedb | 1 | 2.37 (0.56–10.03) | 3.74 (1.04–13.50) | 1.05 (1.00–1.11) | 0.04 |
| Multivariate adjustedc | 1 | 1.90 (0.44–8.20) | 2.68 (0.73–9.80) | 1.04 (0.99–1.10) | 0.10 |
COPD, chronic obstructive pulmonary disease; CVD, cardiovascular disease.
aP-value for the risk per 1 tooth lost.
bAdjusted for age and sex.
cAdjusted for age, sex, body mass index, pack-years of smoking, alcohol consumption, education level, marital status, physical exercise, and medical history of hypertension and diabetes mellitus.
dOrodigestive cancer included as cancers in lip, oral cavity and pharynx, esophagus, stomach, pancreas, liver and colon, rectum, and anus.