Table 3. Hazard ratios(HR) with 95% confidence intervals(CI) for breast cancer incidence according to psychological item responses.
Response to questions | No. of women | Observed person-years | No. of cases | Age-adjusted | Multivariate-adjusteda | ||
---|---|---|---|---|---|---|---|
HR | 95%CI | HR | 95%CI | ||||
Having “ikigai” | |||||||
Disagree | 2,068 | 25,355 | 15 | 1.00 | 1.00 | ||
Neither | 14,505 | 185,952 | 114 | 1.03 | 0.61–1.77 | 1.02 | 0.59–1.75 |
Agree | 9,770 | 125,897 | 61 | 0.80 | 0.46–1.41 | 0.77 | 0.43–1.37 |
Agree strongly | 2,755 | 34,952 | 19 | 0.90 | 0.46–1.78 | 0.81 | 0.41–1.62 |
Decisiveness | |||||||
Disagree | 3155 | 38,349 | 18 | 1.00 | 1.00 | ||
Neither | 19,206 | 247,330 | 140 | 1.19 | 0.73–1.94 | 1.18 | 0.72–1.94 |
Agree | 6,737 | 86,477 | 51 | 1.21 | 0.71–2.08 | 1.07 | 0.62–1.85 |
Ease of anger | |||||||
Disagree | 4,171 | 51,898 | 22 | 1.00 | 1.00 | ||
Neither | 21,013 | 270,672 | 163 | 1.38 | 0.88–2.16 | 1.41 | 0.91–2.21 |
Agree | 3,914 | 49,585 | 24 | 1.08 | 0.61–1.94 | 0.98 | 0.55–1.76 |
Perceived stress | |||||||
Disagree | 4,730 | 57,634 | 28 | 1.00 | 1.00 | ||
Neither | 18,208 | 235,880 | 128 | 1.11 | 0.74–1.67 | 1.21 | 0.80–1.82 |
Agree | 3,214 | 38,859 | 33 | 1.66 | 1.00–2.76 | 1.71 | 1.02–2.85 |
Agree strongly | 2,946 | 39,782 | 20 | 1.00 | 0.56–1.78 | 1.00 | 0.56–1.78 |
aAdjusted for age, study area, educational level, family history of breast cancer, age at menarche, age at menopause, age at first birth, parity, use of exogenous female hormone, alcohol drinking, consumption of green leafy vegetables, daily walking, exercise, sedentary work, height, and body mass index