Table 3.
Characteristics of cohort studies included in the systematic review.
| Author/ Year/ Country | Design/ Study period | Sample/ Sex/ Age | Exposure | Diagnostic Method for Exposure | Outcome | Diagnostic Method for Outcome | Association measure and 95 % CI | Adjustment variables |
|---|---|---|---|---|---|---|---|---|
| Michaud et al./ 2008/ USA[31] | Prospective 1986 to 2004 | 48,375 men health professionals 40 - 75 years | Periodontal disease; Tooth loss. | Self-report and imaging | Gastric Cancer N = 106 | Self-report and Medical records | Periodontal disease In HR*=1.0 (reference) Yes HR*= 1.1 (0.7–1.7) tooth loss (reference=25–32 teeth) HR*= 1.0 17–24 teeth HR*=1.1 (0.6–1.8) 0–16 teeth HR*= 1.1 (0.5–2.1) Periodontal disease In HR**= 1.0 (reference) Yes HR**= 1.3 (0.8–2.0) tooth loss (reference=25–32 teeth) HR**= 1.0 17–24 teeth HR**=1.2 (0.7–2.0) 0–16 teeth HR**= 1.3 (0.6–2.5) | *Smoking history (never; former smoker < 10 years; former smoker >10 years; current smoker 1–14 cigarettes/day; 15–24 cigarettes/day; 25+ cigarettes/day) and packets-year (continuous). **Age (continuous), race (white, Asian and black), physical activity, history of diabetes (yes/no), alcohol (quartile), BMI (<22.22–24.9.25–29.9.30+), geographic location (south, east, northeast, midwest) height (quintiles), calcium intake (quintiles), total caloric intake (quintiles), red meat intake (quintiles), fruit and vegetable intake (quintiles), vitamin D (deciles). |
| Arora et al./ 2010/ Sweden[43] | Prospective Cohort 1963 to 2004 | 15. 333 F = 8. 433 (55 %) M = 6. 900 (45 %) 38 - 77 years | Periodontal disease | Self-report | Gastric Cancer N = 193 | National Registry | Periodontal disease HR= 0.8 (0.4–1.5) Less mobility HR= 0.8 (0.5–1.3) in disease HR= 1.00 (reference) | Sex (male/female), age (years), education (no schooling/secondary/vocation/other), employment (yes/no/housewife/pensioner/other), number of siblings (ordinal), smoking status (smoker current > 1 pack/day; smoker 〈1 pack/day; former smoker 〉 1 pack/day; former smoker < 1 pack/day; never smoked), partner's smoking status (smoker/ex-smoker/never smoked), smoking status of alcohol (alcohol drinker/ex drinker/never), diabetes (yes/no) and BMI (<20, 20–24.9, 25–29.9.>30 kg/m2). |
| Wen et al./ 2013/ Taiwan[44] | Retrospective Cohort 1997 to 2010 | 144.896 F = 71,086 (49. 1 %) M = 73,810 (50. 9 %) >20 years | Periodontitis (ICD-9: 523.3 and 523.4) and Gingivitis (ICD-9: 523.0 and 523.1) | Positive diagnosis and treated at least 3 times | Gastric Cancer N = 151 | Histology through national registry | RR= 1.0 (1.0–1.1) Adjusted HR*= 0.9 (0.7–1.1) | *Fri; It acts; Presence of comorbidity. |
| Chung et al./ 2015/ Taiwan[45] | Retrospective Cohort 2002 to 2009 | 40.140 F = 20,190 (50. 3 %) M = 19,950 (49. 7 %) >40 years | chronic periodontitis | Positive diagnosis based on symptoms, medical history and diagnostic test result. | Gastrointestinal cancer (ICD-9: 150–159) N = 1084 | Medical records | Adjusted HR= 1.2 (1.1–1.2) | Monthly income; Geographic region; Diabetes. |
| Nwizu et al./ 2017/ USA[30] | Prospective Cohort 1999 to 2013 | 65,869 post-menopausal women 50 - 79 years | Periodontal disease | Self-report | Stomach | Self-report in biennial questionnaires and medical records | Stomach HR=1.5 (0.9–2.6) | – |
| Chou et al./ 2018/ Taiwan[46] | Retrospective Cohort 2001 to 2010 | 50,970 F = 24,850 (48.7 %) M = 26,120 (51.3 %) 35 - 80 years | Moderate and severe periodontal disease | Database: diagnosed patients who received an additional procedure code for periodontitis. | Stomach (N = 101) | Patients diagnosed with gastrointestinal cancer according to the ICD-O-3 (C-16) | HR=1.0 (0.6–1.4) | It acts; Fri; Comorbidities (diabetes mellitus/colectomy); index of Charlson; Medication (aspirin/NSAIDs); Socioeconomic level (estimated monthly income and educational level). |
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; DHF, international classification of diseases; DMFT, decayes, missing and filled teeth.