Table 2.
Characteristics of the case-control studies included in the systematic review.
| Author/ Year/ Country | Design/ Study period | Sample/ Sex/ Age | Exposure | Diagnostic Method for Exposure | Outcome | Diagnostic Method for Theutcome | Association measure and 95 % CI | Adjustment variables |
|---|---|---|---|---|---|---|---|---|
| Watabe et al./ 1998/ Japan[37] | case-control 1996 to 1997 | Cases: 242 F = 62 (25. 6 %) M = 180 (74. 4 %) Controls: 484 40 - 79 years | Gingivitis Tooth loss | Self-report | Gastric Cancer | Pathology | Gingivitis OR= 1.2 (0.8–1.8) Tooth loss OR=1.7 (1.2–2.4) | – |
| Hiraki et al./ 2008/ Japan[38] | case-control 2001 to 2005 | Cases: 5240 F = 2541 (48.5 %) M = 2699 (51.5 %) Controls: 10,480 F = 5082 (48.5 %) M = 5398 (51. 5 %) 20 - 79 years | Tooth loss | Self-report | Gastric Cancer N = 702 | Hospital record | 21 teeth left OR=1.0 (reference) 9–20 teeth remaining OR= 1.0 (0.8–1.3) 1–8 teeth remaining OR= 1.1 (0.8–1.5) 0 teeth remaining OR= 0.9 (0.5–1.4) | It acts; Fri; Smoking; Alcohol; Intake of vegetables and fruits; BMI; Regular physical activity. |
| Shakeri et al./ 2013/ Iran[39] | case-control 2004 to 2011 | Cases: 309 F = 83 (26.9 %) M = 226 (73.1 %) Controls: 613 F = 167 (27.2 %) M = 446 (72. 8 %) 40 - 75 years | Tooth loss: Category 1 (≤ 12); Category 2 (13–18); Category 3 (19–24); Category 4 (25–31); Category 5 (32) | Clinical examination | Cardia GC N = 1 61 Non-cardia GC N = 118 | Histology | Tooth loss All gastric adenocarcinomas OR= (reference= Category 1(≤12)) Category 2(13–18) OR=0.5(0.2–1.1) Category 3(19–24) OR =0.9(0.4–1.7) Category 4(25–31) OR =1.6(0.8–3.2) Category 5(32) OR =1.4(0.6–3.0) Cardia GC OR = (reference = Category 1(≤12)) Category 2(13–18) OR = 0.6 (0.2–1.9) Category 3(19–24) OR = 1.6 (0.6–4.35) Category 4(25–31) OR = 3.5 (1.2–9.7) Category 5(32) OR = 1.4 (0.4–4.5) Non-cardia GC OR = (reference= Category 1(≤12)) Category 2(13–18) OR = 0.3 (0.1–1.2) Category 3(19–24) OR = 0.4 (0.1–1.3) Category 4(25–31) OR = 1.7 (0.5–5.6) Category 5(32) OR = 2.1 (0.6–6.9) | It acts; Andthnicity; Education; Consumption of fruits and vegetables, Opium or Tobacco; Denture use. Socioeconomic status |
CI, confidence interval; F, female; M, male; CG, gastric cancer; OR, odds ratio; RR, relative risk; HR, hazard ratio; BMI, body mass index; COPD, chronic obstructive pulmonary disease; ICD, international classification of diseases.