Waterpipe tobacco (WTP) smoking, also known as hookah or shisha, has been gaining popularity worldwide. In Vietnam, this trend has prompted a cohort study to investigate the association between WTP smoking and cancer mortality. This article summarises the key findings from the study published in JAMA Oncology, highlighting the increased risks associated with WTP smoking.

Study Overview

The study aimed to assess the link between WTP smoking and cancer mortality in Vietnam. Conducted as part of the Hanoi Prospective Cohort Study, it included 39,401 participants aged 15 years or older, monitored over a median follow-up period of 11.0 years from 2007 through 2019.

Key Findings

Cancer Mortality Rates

• Total Cancer Deaths: The study identified 554 cancer deaths among the participants.
• Participant Demographics: The average age of participants was 40.4 years, with 52.3% being female.

Risk Assessment

The study used Cox proportional regression models to calculate the hazard ratios (HR) for cancer mortality associated with different smoking statuses:

• Ever Smokers vs. Never Smokers: Ever smokers had a significantly higher risk of cancer mortality (HR, 1.87; 95% CI, 1.48-2.35).
• Exclusive WTP Smokers: Participants who exclusively smoked WTP had the highest risk compared to never smokers (HR, 2.66; 95% CI, 2.07-3.43).
• Dual Smokers (WTP and Cigarettes): Those who smoked both WTP and cigarettes also had an elevated risk (HR, 2.06; 95% CI, 1.53-2.76), higher than exclusive cigarette smokers (HR, 1.86; 95% CI, 1.41-2.45).

Specific Cancer Types

Among male participants (who constituted 95.6% of smokers), exclusive WTP smoking was particularly associated with higher risks of specific cancers:

• Liver Cancer: HR of 3.92 (95% CI, 2.25-6.85)
• Lung Cancer: HR of 3.49 (95% CI, 2.08-5.88)
• Nasopharyngeal Carcinoma: HR of 2.79 (95% CI, 1.27-6.12)
• Stomach Cancer: HR of 4.11 (95% CI, 2.04-8.27)

Implications for Public Health

The study underscores the substantial public health problem posed by WTP smoking in Vietnam. The findings suggest that tailored interventions are necessary within the tobacco control programs to address the unique challenges presented by WTP smoking.

The cohort study in Vietnam shows a clear association between WTP smoking and an increased risk of cancer mortality. This calls for focused efforts in tobacco control to mitigate the health risks associated with WTP smoking, particularly in low- and middle-income countries.

Source: JAMA Oncology