Pearson-Stuttard J, et al. - Researchers aimed at ascertaining the cancer incidence attributable to diabetes and high body-mass index (BMI) as individual risk factors and in combination, by country and sex. In this study, diabetes and high BMI were noted attributing a substantial number of cancer cases. In view of the increasing prevalence of these cancer risk factors, they recommend clinical and public health efforts to focus on identifying optimal preventive and screening measures for whole populations and individual patients.

Methods

• For 175 countries, population attributable fractions for 12 cancers by age and sex were estimated in 2012.
• High BMI was defined as a BMI greater than or equal to 25 kg/m².
• In order to quantify contribution of diabetes and high BMI to site-specific cancers, individually and combined as independent risk factors and in a conservative scenario in which full overlap of risk of diabetes and high BMI was assumed, comprehensive prevalence estimates of diabetes and BMI categories in 2002, assuming a 10-year lag between exposure to diabetes or high BMI and incidence of cancer, combined with relative risks from published estimates, were used.
• To estimate the number of cancer cases attributable to the two risk factors, GLOBOCAN cancer incidence data was utilized.
• The number of cancer cases in 2012 that were attributable to increases in the prevalence of diabetes and high BMI were estimated from 1980 to 2002.
• Researchers performed all analyses at individual country level and grouped them by region for reporting.

Results

• In 2012, 5·7% of all incident cancers were estimated to be attributable to the combined effects of diabetes and high BMI as independent risk factors, corresponding to 804,100 new cases.
• These risk factors seemed attributing 187,600 (24·5%) of 766,000 cases of liver cancer and 121,700 (38·4%) of 317,000 cases of endometrial cancer.
• In the conservative scenario, diabetes and high BMI in combination attributed to about 4.5% (629,000 new cases) of all incident cancers assessed.
• Researchers noted that individually, high BMI (544,300 cases) was noted to be responsible for almost twice as many cancer cases as diabetes (293,300 cases).
• Increases in the prevalence of these risk factors from 1980 to 2002 have attributable role in 25.8% of diabetes-related cancers (equating to 75,600 new cases) and 31.9% of high BMI-related cancers (174,040 new cases).