Individual and Combined Effects of Environmental Risk Factors for Esophageal Cancer Based on Results From the Golestan Cohort Study
- Study type
- Observational study
- Study name
- Golestan Cohort Study
- Design
- Prospective population-based cohort study (north-eastern Iran, Golestan Province)
- Sample size
- 50,045 people; 317 cases of oesophageal squamous cell carcinoma
- Source
- Gastroenterology · 2019
In plain words
Golestan Province is one of the places where squamous cell cancer of the oesophagus (gullet) is seen more often than almost anywhere else in the world. This large study of about 50 thousand people in the region showed that smoking opium, drinking very hot tea, eating little fruit and vegetables, losing teeth, drinking water that is not piped, and smoke inside the home each raise the risk, and the effects add up. About three-quarters of cases of this cancer in the region were attributed to these factors, which means many of them can be prevented.
Key results
Study population
50,045 people aged 40 to 75 years from urban and rural areas of north-eastern Iran who were enrolled between 2004 and 2008 and followed up until the end of December 2017. Data on demographics, diet, lifestyle, socioeconomic status, beverage temperature and various exposures were collected with validated methods and questionnaires and a clinical examination.
Endpoints
Outcome: incidence of oesophageal squamous cell carcinoma (ESCC); hazard ratios estimated with proportional hazards regression models.
Clinical significance and place in guidelines
This prospective study provides the most important population evidence on the causes of the high incidence of oesophageal squamous cell carcinoma in north-eastern Iran and underpins local prevention messages: avoiding opium and tobacco, waiting for tea to cool, eating more fruit and vegetables, oral and dental hygiene, access to safe water and reducing indoor air pollution.
Limitations
The study is observational and does not definitively prove a causal relationship; exposures were mostly measured once at baseline; the number of cancer cases (317) is limited for some subgroup analyses; the findings apply only to the squamous cell type.
This summary was prepared by the editorial team from the published paper; the original paper is the final reference. Read the original abstract on PubMed.