Journal of Cancer Epidemiology / 2014 / Article / Tab 2 / Review Article
Smokeless Tobacco and Oral Cancer in South Asia: A Systematic Review with Meta-Analysis Table 2 Epidemiological studies of chewing tobacco and oral cancer.
Authors
OR (95% CI)
Men OR (95% CI)
Women OR (95% CI) Frequency/day** Duration of use in years*** Tobacco ≤ 5 OR (95% CI) Tobacco 6–10 OR (95% CI) Tobacco > 10/OR (95% CI) Tobacco ≤ 10 yrs/OR (95% CI) Tobacco 11–20
yrs/OR (95% CI) Tobacco > 20 yrs/OR (95% CI) Goud et al. [32 ] 8.5 (4.3–16.5) n/a n/a 8.2 (3.0–22.3) 4.7 (2.0–10.7) 18.4* n/a 4.2* 10.2* Nandakumar et al. [33 ] 12.9 (7.5–22.3) 3.6 (1.7–7.9) 25.3 (11.2–57.3) 9.3 (4.9–17.5) 12.8 (6.6–25.0) 16.6 (6.3–44.3) n/a n/a n/a Rao et al. [34 ] 3.6 (2.5–5.6) 3.6 (2.5–5.6) n/a n/a 2.8 (2.2–3.5)+ 3.8* 1.2 (0.9–1.8) 3.9 (2.7–5.7) 4.1* Khan et al. [35 ] 2.3 (0.7–7.4) n/a n/a n/a n/a n/a n/a n/a n/a Wasnik et al. [36 ] 7.9 (4.1–13.5) n/a n/a 2.1* 8.1 (3.7–17.9) 20.0 (8.1–48.9) n/a n/a 10.9 (5.9–20.0) Dikshit and kanhere [37 ] 5.8 (3.6–9.5) 5.8 (3.6–9.5) n/a 2.0 (1.0–3.8) 6.7 (3.7–12.1) 13.9 (7.1–27.2) n/a n/a n/a Znaor et al. [40 ] 5.0 (4.2–5.9) 5.0 (4.2–5.9) n/a 5.0* 11.9 (8.9–15.9)++ n/a n/a 3.1 (2.5–3.8)+++ 9.5* Gangane et al. [42 ] 10.0 (6.7–14.8) n/a n/a n/a n/a n/a n/a n/a n/a Subapriya et al. [41 ] 2.9* n/a n/a n/a n/a n/a 2.9* 2.5* 2.7* Basu et al. [43 ] 2.0 (0.9–4.4) n/a n/a n/a n/a n/a n/a n/a n/a Jayalekshmi et al. [45 ] 5.5 (3.3–9.0) n/a 5.5 (3.3–9.0) 3.3 (1.7–6.4) 7.8 (4.4–13.9) 9.2 (4.5–18.7) n/a n/a n/a Jayalekshmi et al. [46 ] 5.4 (3.0–9.0) 5.4 (3.0–9.0) n/a 1.9 (1.2–2.8) n/a n/a n/a n/a n/a Pednekar et al. [47 ] 1.4 (1.0–2.1)**** 1.4 (1.0–2.1) n/a 1.1 (0.9–1.4) 1.1 (0.9–1.4) n/a 0.8 (0.4–1.7) 1.0 (0.7–1.4) 1.1 (1–1.4) Madani et al. [48 ] 8.3 (5.4–13.0) n/a n/a n/a n/a n/a n/a n/a n/a Ray et al. [49 ] 3.9 (2.4–6.1) 2.8 (1.5–5.1) 6.4 (3.2–12.7) n/a n/a n/a n/a n/a n/a
OR: odds ratio, CI: confidence interval, *95% CI not reported and/or could not be calculated, **daily frequency in number of times tobacco is chewed in a day, ***total duration of habit in “years,” ****for cancer of lip, oral cavity, and pharynx only, n/a: not available, + 1–10/day, ++ >5/day, +++ 0–19 years, and nonchewers taken as reference category. Frequency/intensity OR are for both genders.