Table 1.
Characteristics of studies on the association between waterpipe smoking and cancer
| References | Study, year Region, country |
Cases/controls | OR (95 % CI) | Adjustments | Controls characteristics | Study quality (NOS) | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Selection | Comparability | Exposure | NOS | |||||||
| Head and neck | ||||||||||
| Jaferey (1976) | CC, 1967–1972 Karachi, Pakistan |
1192/3562 | 3.10 (2.23–4.29) | Derived from frequencies, adjusted for sex, cigarettes and bidi smoking | Healthy controls matched for age, sex and place of birth | ●●●● | ●● | ○○●○ | 7 | |
| Feng (2009) | CC, 2002–2005 Algeria, Morocco, Tunisia |
636/615 | 0.49 (0.20–1.23) | Matched analysis adjusted for age and socio-economical status | Hospital controls or friends and family members matched for centre age, sex and childhood household type (urban/rural) | ●●○● | ○● | ○○●● | 6 | |
| Khlifi (2013) | CC, 2007–2009 Sfax, Tunisia |
169/351 | 2.73 (1.65–4.41) | Adjusted for potential risk factors including smoking | Population based controls | ●●●● | ●● | ○○●○ | 7 | |
| Quadri (2015) | CC, 2014 Jazan, Saudi Arabia |
48/96 | 4.20 (1.32–13.3) | Adjusted for other forms of smoking | Hospital controls matched on sex, age (±5 years) and location | ●●○● | ●● | ○○●○ | 6 | |
| Esophagus | ||||||||||
| Cook-Mozaffari (1979) | CC, 1975–1976 Caspian littoral, Iran |
217/343 M 127/254 F |
1.25 (0.74–2.08) 1.15 (0.43–2.94) |
Matched analysis | Matched on sex, age (±5 years) and residence | ○●●● | ○● | ○○○○ | 4 | |
| Nasrollahzadeh (2008) | CC, 2003–2007 Golestan, Iran |
300/571 | 1.69 (0.76–3.77)a | Matched analysis adjusted for education and ethnicity | Matched on sex, age (±2 years) and residence | ●●●● | ●● | ○○●○ | 7 | |
| Malik (2010) | CC, 2006–2008 Kashmir Valley, India |
135/195 | 21.4 (11.6–39.5) | Adjusted for age and sex | Routine check-up controls matched for age and sex | ●●○● | ○● | ○○●○ | 5 | |
| Khan (2011) | CC, 2008 Kashmir Valley, India |
100/100 | 9.11 (4.44–18.7) | Derived from frequencies (66/28/6 vs. 15/58/27) |
●●●○● | ○○ | ○○●○ | 4 | ||
| Dar (2012) | CC, 2008–2012 Kashmir Valley, India |
702/1663 | 1.85 (1.41–2.44) | Adjusted for age, ethnicity, religion, residence, education, cigarette, nass, bidi, cannabis, gutka, alcohol, fruit and vegetables intake | Hospital-based controls matched on sex, age (±5 years) and residence | ●●○● | ●● | ○○●● | 7 | |
| Stomach | ||||||||||
| Pourfarzi (2009) | CC, 2003–2005 Ardabil, Iran |
217/394 | 1.14 (0.29–4.42) | Adjusted for gender, age group, education, family history of GC, various food habits and H. Pylori infection | Community controls matched on sex, age (±5 years) and residence | ●●●● | ●● | ○○●○ | 7 | |
| Shakeri (2013) | CC, 2004–2011 Golestan, Iran |
309/613 | 1.10 (0.30–3.30) | Adjusted for age, ethnicity, education, fruit and vegetable consumption, socioeconomic status, opium, cigarette and nass use. | Healthy controls matched on sex, age (±5 years) and residence | ●●●● | ●● | ○○●○ | 7 | |
| Karajibani (2014) | CC, 2011–2012 Zahedan, Iran |
46/46 | 4.50 (1.17–17.4) | Derived from frequencies (11/46 vs. 3/46) |
Matched on sex, age, job, economic status | ●●○● | ○○ | ○○●○ | 4 | |
| Sadjadi (2014) | Cohort of Helicobacter pylori infected subjects; Ardabil, Iran | 36/928 | 3.44 (1.66–7.11) | Adjusted for age, sex, family history of cancer, cigarettes smoking, opium, alcohol, fruit and vegetables and salt. | Average follow-up of 10 years | ●●●● | ●● | ●●● | 9 | |
| Lung | ||||||||||
| Qiao (1989) | CC, 1967–1984 Yunnan, China |
107/107 | 1.90 (0.40–9.40)* | Adjusted for age | ●●●● | ●● | ○○●○ | 7 | ||
| Lubin (1992) | CC, 1984–1988 Yunnan, China |
427/1011 | 1.78 (0.80–4.20)* | Adjusted for age, residence, type of respondent and years of work | Matched on age (±5 years) | ●●●● | ●● | ○○●○ | 7 | |
| Hsairi (1993) | CC, 1988–1989 Tunis, Tunisia |
110/110 | 5.70 (1.20–7.60) | Adjusted for age, sex, cigarette consumption and cannabis use | Matched on sex, age (±5 years) and cigarettes (±5 cig/day) | ●●●● | ●● | ○○●○ | 7 | |
| Gupta (2001) | CC, 1995–1997 Chandigarh, India |
265/525 | 1.94 (0.85–4.44) | Adjusted for age and education | Hospital controls matched on sex and age | ●●○● | ○● | ○○●○ | 5 | |
| Koul (2011) | CC, 2005–2006 Kashmir Valley, India |
251/500 | 5.83 (3.95–8.60)* | Crude Odds Ratio | Matched on age and residence | ●●○● | ●● | ○○●○ | 6 | |
| Aoun (2013) | CC, 2012 Beirut, Lebanon |
50/100 | 6.00 (1.78–20.3) | Crude Odds Ratio | Hospital controls and visitors matched on sex | ●●○● | ○○ | ○○●○ | 4 | |
| Bladder | ||||||||||
| Makhyoun (1974) | CC, 1966–1971 Alexandria and Tanta, Egypt |
Bilharzial 278/278 Ctr 87/87 |
1.08 (0.77–1.51) 0.89 (0.45–1.76) |
Derived from frequencies (113/278 vs. 108/278) (21/87 vs. 23/87) |
Hospital controls matched for antecedent bilharziasis infection, residence and occupation | ●●○● | ○○ | ○○●○ | 4 | |
| Bedwani (1997) | CC, 1994–1996 Alexandria, Egypt |
151/157 | 0.80 (0.20–4.00) | Adjusted for age, education, housing, history of schistosomiasis, high risk occupation and tobacco smoking | Hospital controls with acute non-neoplastic, non-urinary tract, non smoking-related condition | ●●○● | ●● | ○○●○ | 6 | |
| Wolpert (2010) | CC, N/a Cairo, Minia, Assiut, Egypt |
239/540 | 1.70 (0.38–7.67) | Derived from frequencies (3/239 vs. 4/540) |
Matched on sex, age (±5 years) and residence | ●●●● | ○● | ○○●○ | 6 | |
| Feki-Tounsi (2013) | CC, 2007–2010 Sfax, Tunisia |
125/204 | 1.32 (0.35–5.00) | Derived from frequencies (4/125 vs. 5/204) |
Hospital c ontrols consulting for benign disease | ●●○● | ○○ | ○○●○ | 4 | |
| Amr (2014) | CC, 2006–2011 Cairo, Egypt |
1840/2616 | 1.42 (1.11–1.83)* | Crude Odds Ratios | Residence matched, population-based controls | ●●●● | ●○ | ○○●○ | 6 | |
| Colon-rectum | ||||||||||
| Bener (2010) | CC, 2008–2009 Doha, Qatar |
146/282 | 1.02 (0.62–1.68) | Derived from frequencies (30/146 vs. 57/282) |
Matched on sex, race and age (±5 years) | ●●○● | ○● | ○○● | 6 | |
| Azizi (2015) | CC, 2013–2014 East Azerbaijan, Iran |
207/207 | 1.26 (0.49–3.27) | Derived from frequencies (10/207 vs. 8/207) |
Cancer free hospital controls | ●●○● | ○● | ○○●○ | 5 | |
| Liver | ||||||||||
| Soliman (2010) | CC, 2007–2009 Tanta, Gharbiah, Egypt |
150/150 | 1.13 (0.62–2.78) | Matched analysis adjusted for viral infection | Hospital healthy visitors matched on sex and age (±5 years) | ●●○● | ○● | ○○●○ | 5 | |
| All cancer deaths | ||||||||||
| Wu (2013) | Cohort, 2000–2011 Araihazar, Bangladesh |
47/20033 | 1.30 (0.78–2.18) 2.51 (1.08–5.82) |
Adjusted for age, BMI, education | Average follow-up of 7.6 years | ●●●● | ○● | ●●● | 8 | |
CC case–control study, NOS Newcastle Ottawa Scale score
aRisk estimate for exclusive waterpipe smokers vs. non-smokers of any type of tobacco