Table 2.
Associations between smoking status and osteoarthritis (OA) in Korean adults aged 50 years or over in Korean National Health and Nutrition Examination Survey (KNHANES) 2010–2012
| Adjusted for age and sex |
Fully adjusted* |
Selectively adjusted† |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Factors | n (case) | OR | 95% CI | p Value | OR | 95% CI | p Value | OR | 95% CI | p Value |
| Knee OA or hip OA‡ | ||||||||||
| All | ||||||||||
| Non-smoking | 4231 (815) | 1 | 1 | 1 | ||||||
| Current smoking | 1430 (108) | 1.058 | 0.763 to 1.467 | 0.7350 | 1.013 | 0.683 to 1.503 | 0.9481 | 1.047 | 0.741 to 1.480 | 0.7927 |
| Past smoking | 2153 (148) | 0.726 | 0.522 to 1.010 | 0.0576 | 0.749 | 0.527 to 1.065 | 0.1072 | 0.708 | 0.506 to 0.991 | 0.0439 |
| Indirect smoking | 1228 (185) | 1.132 | 0.914 to 1.401 | 0.2555 | 1.084 | 0.847 to 1.387 | 0.5204 | 1.076 | 0.866 to 1.337 | 0.5101 |
| Men§ | ||||||||||
| Non-smoking | 457 (34) | 1 | 1 | 1 | ||||||
| Current smoking | 1236 (69) | 0.903 | 0.548 to 1.486 | 0.6868 | 0.814 | 0.440 to 1.506 | 0.5114 | 0.880 | 0.525 to 1.474 | 0.6264 |
| Past smoking | 2004 (114) | 0.665 | 0.415 to 1.064 | 0.0892 | 0.694 | 0.410 to 1.175 | 0.1737 | 0.675 | 0.420 to 1.086 | 0.1053 |
| Indirect smoking | 209 (6) | 0.271 | 0.088 to 0.828 | 0.0220 | 0.391 | 0.122 to 1.260 | 0.1157 | 0.314 | 0.102 to 0.966 | 0.0434 |
| Women§ | ||||||||||
| Non-smoking | 3774 (781) | 1 | 1 | 1 | ||||||
| Current smoking | 194 (39) | 1.086 | 0.685 to 1.720 | 0.7263 | 1.187 | 0.688 to 2.048 | 0.5379 | 1.136 | 0.700 to 1.843 | 0.6055 |
| Past smoking | 149 (34) | 0.613 | 0.354 to 1.061 | 0.0804 | 0.610 | 0.344 to 1.084 | 0.0923 | 0.603 | 0.347 to 1.049 | 0.0732 |
| Indirect smoking | 1019 (179) | 1.209 | 0.966 to 1.513 | 0.0968 | 1.113 | 0.861 to 1.44 | 0.4136 | 1.138 | 0.905 to 1.430 | 0.2690 |
| Knee OA¶ | ||||||||||
| All | ||||||||||
| Non-smoking | 4235 (808) | 1 | 1 | 1 | ||||||
| Current smoking | 1430 (104) | 1.047 | 0.752 to 1.458 | 0.7866 | 1.008 | 0.676 to 1.503 | 0.9682 | 1.033 | 0.728 to 1.467 | 0.8540 |
| Past smoking | 2154 (148) | 0.737 | 0.528 to 1.028 | 0.0719 | 0.756 | 0.530 to 1.079 | 0.1239 | 0.716 | 0.510 to 1.005 | 0.0533 |
| Indirect smoking | 1228 (184) | 1.142 | 0.922 to 1.415 | 0.2231 | 1.090 | 0.850 to 1.396 | 0.4973 | 1.085 | 0.872 to 1.350 | 0.4660 |
| Men§ | ||||||||||
| Non-smoking | 457 (34) | 1 | 1 | |||||||
| Current smoking | 1236 (65) | 0.871 | 0.527 to 1.441 | 0.5918 | 0.787 | 0.423 to 1.464 | 0.4495 | 0.841 | 0.499 to 1.418 | 0.5165 |
| Past smoking | 2004 (114) | 0.665 | 0.415 to 1.065 | 0.0897 | 0.692 | 0.408 to 1.174 | 0.1724 | 0.671 | 0.416 to 1.082 | 0.1014 |
| Indirect smoking | 209 (6) | 0.273 | 0.089 to 0.837 | 0.0231 | 0.397 | 0.123 to 1.282 | 0.1226 | 0.321 | 0.104 to 0.989 | 0.0477 |
| Women§ | ||||||||||
| Non-smoking | 3778 (774) | 1 | 1 | |||||||
| Current smoking | 194 (39) | 1.101 | 0.695 to 1.743 | 0.6819 | 1.208 | 0.700 to 2.085 | 0.4971 | 1.155 | 0.711 to 1.874 | 0.5609 |
| Past smoking | 150 (34) | 0.619 | 0.357 to 1.071 | 0.0864 | 0.613 | 0.343 to 1.094 | 0.0976 | 0.605 | 0.347 to 1.053 | 0.0756 |
| Indirect smoking | 1019 (178) | 1.219 | 0.973 to 1.526 | 0.0848 | 1.120 | 0.865 to 1.452 | 0.3901 | 1.147 | 0.911 to 1.444 | 0.2418 |
Logistic regression analysis.
*Adjusted for age, sex, household income, education, occupation, residential area, alcohol drinking, dietary habits, exercise habits, experience of depressive symptoms, body mass index and fasting blood glucose.
†Backward elimination method was used with significance set at p<0.05.
‡Patients with knee joint pain and knee joint Kellgren-Lawrence grade ≥2 (mild) or with hip joint pain and hip joint Kellgren-Lawrence grade ≥2 (mild).
§Sex was excluded in adjustments.
¶Patients with knee joint pain and knee joint Kellgren-Lawrence grade ≥2 (mild).