Waterpipe tobacco smoking and risk of all-cause mortality: a prospective cohort study.

BACKGROUND: Despite an increasing proportion of smokers who use non-cigarette products, the harmfulness of these is inconsistent. This study aimed to evaluate the impact of waterpipe tobacco (WTP) smoking on all-cause mortality. METHODS: A prospective cohort study followed up on 35 646 participants from 2007 to 2019 in Northern Viet Nam. Data for each type of cigarette and WTP smoking were collected based on demographic lifestyle and semi-quantitative food frequency questionnaires. Smokers were categorized as current smokers and former smokers who were lifetime ever smokers but stopped smoking >6 months before the interview. Data on all-cause mortality (2449 deaths) were obtained from medical records at the state health facilities. The hazard ratios (HRs) and 95% CIs for mortality were estimated using a Cox proportional-hazards model. RESULTS: Compared with non-smokers, ever smokers had a higher all-cause mortality risk (HR = 1.29, 95% CI = 1.16-1.43). Current WTP (HR = 1.37, 95% CI = 1.19-1.57), current cigarette (HR = 1.40, 95% CI = 1.22-1.60) and former WTP smokers (HR = 1.39, 95% CI = 1.10-1.76) showed an elevated risk of dying. The mortality risk was significantly elevated in dual smokers using WTP and cigarettes (HR = 1.55, 95% CI = 1.35-1.79) and exclusive WTP smokers (HR = 1.38, 95% CI = 1.21-1.57). Elevated risk was observed for the main targeted attractions of cancer, diabetes and heart diseases. Smoking cessation of >10 years decreased the risk of all-cause mortality (HR = 0.61, 95% CI = 0.44-0.85) and cancer (HR = 0.24, 95% CI = 0.11-0.52). CONCLUSIONS: WTP smoking increases the risk of all-cause mortality. A unique programme to control exposure to WTP should be a high priority in Viet Nam and other countries.

Exclusive waterpipe smoking and the risk of nasopharynx cancer in Vietnamese men, a prospective cohort study.

Tobacco smoking is carcinogenic to humans. Besides cigarettes, the most common form of tobacco smoking, there was sparse evidence of waterpipe's carcinogenicity-induced nasopharyngeal cancer (NPC). This study investigated the association between waterpipe smoking and NPC mortality. Our study followed up with 20,144 eligible man participants from nine northern Vietnam communes between 2007 and 2019. Face-to-face interviews were conducted to gather data on exclusive waterpipe and cigarette smoking and dietary intake using structured semi-quantitative food frequency and lifestyle questionnaires. Nasopharyngeal cancer was determined by accessing the medical records at the state health facilities. We estimated the Cox proportional hazard ratio and 95% confidence intervals, HR (95% CI). The proportion of never smokers, exclusive waterpipe, exclusive cigarette, and dual waterpipe and cigarette smokers was 55.8%, 14.5%, 16.6%, and 13.1%, respectively. Exclusively waterpipe smokers increased the risk of NPC death compared to exclusively cigarette smokers, HR (95% CI): 4.51 (1.25, 16.31), p = 0.022. A dose-dependent positive relationship between NPC and exclusive waterpipe smoking was significantly seen for higher intensity HR (95% CI): 1.35 (1.07, 1.71), earlier age of smoking initiation HR (95% CI): 1.26 (1.06, 1.50), longer duration HR (95% CI): 1.31 (1.04, 1.66), and the cumulative number of a smoke lifetime HR (95% CI): 1.37 (1.08, 1.74). We observed a significant positive association between exclusive waterpipe smoking and NPC in men. The findings suggested that waterpipe smoking is likely more harmful than cigarettes in developing this cancer. A firm tobacco control against waterpipe smoking is highly recommended.

Calcium Intake Contributed by Whole Foods and Gastric Cancer in Viet Nam: A Case­Control Study.

BACKGROUND: Recent studies revealed the potential tumor-suppressive effects of calcium. We aimed to investigate the association between dietary calcium intake contributed by whole foods and gastric cancer. METHODS: 466 gastric cancer cases and 1531 controls were extracted from the completed case-control studies in hospitals in Hanoi from 2017 to 2019. A validated semi-quantitative food frequency questionnaire was used to obtain data via face-to-face interviews with the trained interviewer. Calcium intake was calculated based on the food frequency intake per year. Adjusted odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. RESULTS: The study participants consumed less than 50% of 700 mg/day compared to the recommended calcium intake. With increasing calcium intake, we found a reduction in gastric cancer in both genders, men and women (adjusted OR and 95%CI, 5th vs. 1st quintile: 0.50 (0.36, 0.70), p_trend 0.000; 0.62 (0.42, 0.92), p_trend 0.019; and 0.30 (0.16, 0.57), p_trend 0.000, respectively). The inverse association remained in the subgroups of never-smokers and those with positive H. pylori infection. CONCLUSION: We observed substantial benefits of calcium intake from whole foods against gastric cancer in the Vietnamese population with a low nutritious status.