Chewing of betel nut with or without tobacco and risk of stomach cancer
| Habits . | Cases . | Controls . | Univariate*, OR (95% CI) . | Multivariate†, adjusted OR (95% CI) . | ||||
|---|---|---|---|---|---|---|---|---|
| Chewing status | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| Ex-chewers | 83 | 120 | 2.0 (1.4-2.9) | 1.6 (0.7-2.6) | ||||
| Current chewers | 115 | 150 | 2.2 (1.6-3.1) | 1.5 (0.5-2.2) | ||||
| Chewing ingredients | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| Betel nut + betel leaf | 110 | 189 | 1.7 (1.2-2.3) | 1.2 (0.7-2.1) | ||||
| Tobacco alone | 25 | 20 | 3.7 (1.9-7.2) | 2.6 (1.1-4.2) | ||||
| Betel nut + Betel leaf + tobacco | 54 | 56 | 2.8 (1.8-4.4) | 2.0 (1.3-5.3) | ||||
| Chewing frequency/d | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| ≤3 | 82 | 110 | 1.03 (0.7-1.5) | 0.6 (0.1-4.4) | ||||
| >3 | 116 | 160 | 2.2 (1.5-2.9) | 1.4 (1.0-4.3) | ||||
| Ptrend < 0.001 | ||||||||
| Age began (y) | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| ≤10 | 27 | 39 | 2.0 (1.2-3.5) | 1.3 (0. 3-1.4) | ||||
| 11-15 | 53 | 102 | 1.5 (0.8-1.9) | 0.9 (0.4-1.9) | ||||
| 16-20 | 68 | 79 | 1.5 (1.0-2.3) | 0.7 (0.06-3.3) | ||||
| 21-30 | 30 | 34 | 2.6 (1.4-4.5) | 1.9 (1.1-3.1) | ||||
| ≥31 | 20 | 16 | 3.7 (1.7-7.7) | 2.6 (1.6-5.5) | ||||
| Trend test not significant | ||||||||
| Years of chewing | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| ≤15 | 66 | 96 | 2.0 (1.3-3.0) | 1.2 (0.06-4.4) | ||||
| 16-30 | 48 | 64 | 2.2 (1.4-3.4) | 1.3 (0.65-5.4) | ||||
| >30 | 72 | 103 | 2.0 (1.4-3.0) | 1.1 (0.03-6.4) | ||||
| Trend test not significant | ||||||||
| Years since stopped chewing | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| <10 | 44 | 52 | 2.5 (1.5-4.0) | 1.1 (0.01-6.4) | ||||
| 10-20 | 25 | 40 | 1.8 (1.04-3.2) | 0.74 (0.02-4.2) | ||||
| 20< | 14 | 24 | 1.7 (0.8-3.6) | 0.61 (0.03-5.6) | ||||
| Trend test not significant | ||||||||
| Cumulative dose to chewing of betel nut + betel leaf | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| <50,000 | 42 | 76 | 1.6 (1.0-2.5) | 0.63 (0.05-3.2) | ||||
| 50,000-100,000 | 60 | 88 | 2.0 (1.3-3.0) | 1.3 (0.08-5.3) | ||||
| >100,000 | 84 | 68 | 3.6 (2.4-5.4) | 2.3 (1.2-4.5) | ||||
| Ptrend < 0.01 | ||||||||
| Cumulative dose to amount of tobacco chewing (mg) | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| <20,000 | 13 | 18 | 2.1 (0.9-4.7) | 1.5 (0.04-4.8) | ||||
| >20,000 | 24 | 22 | 3.2 (1.6-6.2) | 2.6 (1.2-5.6) | ||||
| Habits . | Cases . | Controls . | Univariate*, OR (95% CI) . | Multivariate†, adjusted OR (95% CI) . | ||||
|---|---|---|---|---|---|---|---|---|
| Chewing status | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| Ex-chewers | 83 | 120 | 2.0 (1.4-2.9) | 1.6 (0.7-2.6) | ||||
| Current chewers | 115 | 150 | 2.2 (1.6-3.1) | 1.5 (0.5-2.2) | ||||
| Chewing ingredients | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| Betel nut + betel leaf | 110 | 189 | 1.7 (1.2-2.3) | 1.2 (0.7-2.1) | ||||
| Tobacco alone | 25 | 20 | 3.7 (1.9-7.2) | 2.6 (1.1-4.2) | ||||
| Betel nut + Betel leaf + tobacco | 54 | 56 | 2.8 (1.8-4.4) | 2.0 (1.3-5.3) | ||||
| Chewing frequency/d | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| ≤3 | 82 | 110 | 1.03 (0.7-1.5) | 0.6 (0.1-4.4) | ||||
| >3 | 116 | 160 | 2.2 (1.5-2.9) | 1.4 (1.0-4.3) | ||||
| Ptrend < 0.001 | ||||||||
| Age began (y) | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| ≤10 | 27 | 39 | 2.0 (1.2-3.5) | 1.3 (0. 3-1.4) | ||||
| 11-15 | 53 | 102 | 1.5 (0.8-1.9) | 0.9 (0.4-1.9) | ||||
| 16-20 | 68 | 79 | 1.5 (1.0-2.3) | 0.7 (0.06-3.3) | ||||
| 21-30 | 30 | 34 | 2.6 (1.4-4.5) | 1.9 (1.1-3.1) | ||||
| ≥31 | 20 | 16 | 3.7 (1.7-7.7) | 2.6 (1.6-5.5) | ||||
| Trend test not significant | ||||||||
| Years of chewing | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| ≤15 | 66 | 96 | 2.0 (1.3-3.0) | 1.2 (0.06-4.4) | ||||
| 16-30 | 48 | 64 | 2.2 (1.4-3.4) | 1.3 (0.65-5.4) | ||||
| >30 | 72 | 103 | 2.0 (1.4-3.0) | 1.1 (0.03-6.4) | ||||
| Trend test not significant | ||||||||
| Years since stopped chewing | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| <10 | 44 | 52 | 2.5 (1.5-4.0) | 1.1 (0.01-6.4) | ||||
| 10-20 | 25 | 40 | 1.8 (1.04-3.2) | 0.74 (0.02-4.2) | ||||
| 20< | 14 | 24 | 1.7 (0.8-3.6) | 0.61 (0.03-5.6) | ||||
| Trend test not significant | ||||||||
| Cumulative dose to chewing of betel nut + betel leaf | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| <50,000 | 42 | 76 | 1.6 (1.0-2.5) | 0.63 (0.05-3.2) | ||||
| 50,000-100,000 | 60 | 88 | 2.0 (1.3-3.0) | 1.3 (0.08-5.3) | ||||
| >100,000 | 84 | 68 | 3.6 (2.4-5.4) | 2.3 (1.2-4.5) | ||||
| Ptrend < 0.01 | ||||||||
| Cumulative dose to amount of tobacco chewing (mg) | ||||||||
| Non-chewers | 131 | 388 | 1.0 (reference) | 1.0 (reference) | ||||
| <20,000 | 13 | 18 | 2.1 (0.9-4.7) | 1.5 (0.04-4.8) | ||||
| >20,000 | 24 | 22 | 3.2 (1.6-6.2) | 2.6 (1.2-5.6) | ||||
Matched (cases and controls were matched for age and sex) univariate OR estimated by conditional logistic regression analysis.
Adjusted ORs (adjusted for alcohol drinking, smoking, using of tuibur, level of education, occupation, and income group) obtained by matched conditional multiple logistic regression analysis using maximum likelihood approach.