Incidence rate ratios for personal risk factors
| Person-time (100 person-years) | Dominant hand CTS | Incidence rate (per 100 person-years) | Incidence rate ratio | Lower 95% CI | Upper 95% CI | |
|---|---|---|---|---|---|---|
| Gender | 83.30 | 204 | ||||
| Male | 39.41 | 81 | 1.85 | 1.00 | – | – |
| Female | 43.89 | 123 | 3.12 | 1.69 | 1.27 | 2.27 |
| Age (years) | 83.31 | 204 | ||||
| <30 years of age | 29.18 | 32 | 1.10 | 1.00 | – | – |
| ≥30 and <40 years of age | 19.45 | 47 | 2.42 | 2.20 | 1.38 | 3.57 |
| ≥40 and <50 years of age | 20.28 | 69 | 3.40 | 3.10 | 2.01 | 4.88 |
| ≥50 years of age | 14.40 | 56 | 3.89 | 3.55 | 2.26 | 5.66 |
| Ethnicity | 77.01 | 183 | ||||
| Caucasian | 47.42 | 126 | 2.66 | 1.00 | – | – |
| Hispanic | 9.43 | 16 | 1.70 | 0.64 | 0.35 | 1.08 |
| African–American | 14.28 | 25 | 1.75 | 0.66 | 0.41 | 1.02 |
| Asian | 3.42 | 9 | 2.63 | 0.99 | 0.44 | 1.94 |
| Other | 2.46 | 7 | 2.84 | 1.07 | 0.42 | 2.27 |
| Educational level | 82.82 | 200 | ||||
| Some high school or less | 9.92 | 34 | 3.43 | 1.00 | – | – |
| High school graduate or above | 72.90 | 166 | 2.28 | 0.66 | 0.46 | 0.99 |
| Body mass index | 83.02 | 203 | ||||
| Body mass index (<30 kg/m2: normal or overweight) | 55.25 | 104 | 1.88 | 1.00 | – | – |
| Body mass index (≥30 kg/m2: obese) | 27.77 | 99 | 3.56 | 1.89 | 1.42 | 2.52 |
| Overall health status | 43.73 | 161 | ||||
| Very good or excellent | 20.59 | 55 | 2.67 | 1.00 | – | – |
| Good | 18.24 | 83 | 4.55 | 1.70 | 1.20 | 2.44 |
| Poor or fair | 4.90 | 23 | 4.70 | 1.76 | 1.03 | 2.91 |
| Medical condition | 83.16 | 204 | ||||
| No medical condition | 75.21 | 176 | 2.34 | 1.00 | – | – |
| Medical condition | 7.95 | 28 | 3.52 | 1.50 | 0.97 | 2.25 |
| Diabetes mellitus | 2.75 | 7 | 2.56 | 1.08 | 0.43 | 2.26 |
| Rheumatoid arthritis | 1.49 | 6 | 4.02 | 1.66 | 0.60 | 3.69 |
| Thyroid disease | 3.77 | 16 | 4.24 | 1.81 | 1.01 | 3.01 |
| Gout | 1.16 | 6 | 5.17 | 2.23 | 0.81 | 4.94 |
| Previous DUE MSD | 74.85 | 158 | ||||
| No previous DUE MSD | 67.17 | 127 | 1.89 | 1.00 | – | – |
| Previous DUE MSD | 7.68 | 31 | 4.04 | 2.13 | 1.39 | 3.18 |
| Smoking status | 82.99 | 201 | ||||
| Never smoked | 44.80 | 105 | 2.34 | 1.00 | – | – |
| Currently smoked | 23.17 | 59 | 2.55 | 1.09 | 0.78 | 1.51 |
| Previously smoked | 15.02 | 37 | 2.46 | 1.05 | 0.70 | 1.54 |
| Weekly aerobic activity | 32.20 | 100 | ||||
| <3 h/week | 17.63 | 55 | 3.12 | 1.00 | – | – |
| ≥3 h/week | 14.57 | 45 | 3.09 | 0.99 | 0.65 | 1.50 |
| Weekly hand intensive activity (non-occupational) | 42.56 | 145 | ||||
| <3 h/week | 11.73 | 53 | 4.52 | 1.00 | – | – |
| ≥3 h/week | 30.83 | 92 | 2.98 | 0.66 | 0.47 | 0.94 |
*Medical condition includes diabetes mellitus, rheumatoid arthritis, thyroid disease and pregnancy. There were no pregnant women who became cases.
DUE, Distal upper extremity; MSD, Musculoskeletal disorder