Older people with type 2 diabetes faced a higher burden of cancer mortality in recent years, according to a U.K. study.
In a cohort of over 137,000 individuals with type 2 diabetes, all-cause mortality rates dropped among all age groups from 1998-2018, reported Suping Ling, PhD, of the University of Leicester in England, and colleagues.
However, this was juxtaposed by an increase in cancer-related morality rates for people ages 75 and 85 with type 2 diabetes, they wrote in Diabetologia.
During the median follow-up of 8.4 years, those ages 75 with diabetes saw a 1.2% average annual percentage change (AAPC) in cancer mortality rate, while those ages 85 saw a 1.6% bump each year. On the other hand, those ages 55 and 65 saw a respective 1.4% and 0.2% annual drop in cancer mortality.
Ling’s group examined who was most impacted by this rising cancer mortality rate, and reported that people with morbid obesity (BMI 35-plus) saw one of the highest annual increases of 5.8%. Comparatively, those with a normal body weight (BMI 18.5-24.9) with type 2 diabetes only saw an average 0.7% increase.
Additionally, there was a 1.5% AAPC in cancer mortality for women versus a 0.5% increase for men. The authors noted that “[a]ll-cancer mortality rates and proportions of cancer deaths were higher in men than women for most of the 1998-2018 period, with the gap in both rates and proportions being smaller around 2012-2014 and widening since 2014.”
There also appeared to be an increasing trend in cancer mortality rates for former or current smokers (0.6% and 3.4%, respectively), as well as white individuals (2.4%), whereas downward trends were seen for nonsmokers (-1.4%) and other ethnic groups (-3.4%).
And those living in the least deprived areas saw a 1.5% AAPC compared with a 1% increase for those living in the most deprived areas.
Certain cancer-specific mortality trends emerged among this population with diabetes. Compared with the general population, there were significantly higher standardized mortality ratios (SMRs) for several cancer types among people with type 2 diabetes from 1998-2018:
- Colorectal: SMR 2.40 (95% CI 2.26-2.54)
- Pancreatic: SMR 2.12 (95% CI 1.99-2.25)
- Liver: SMR 2.13 (95% CI 1.94-2.33)
- Endometrial: SMR 2.08 (95% CI 1.76-2.44)
- Lung: SMR 1.04 (95% CI 1.00-1.08)
- Breast in women: SMR 1.09 (95% CI 1.01-1.18)
“The prevention of cardiovascular disease has been, and is still considered, a priority in people with diabetes. Our results challenge this view by showing that cancer may have overtaken cardiovascular disease as a leading cause of death in people with type 2 diabetes,” stated Ling’s group.
“Cancer prevention strategies therefore deserve at least a similar level of attention as cardiovascular disease prevention, especially for colorectal, pancreatic, liver and endometrial cancer, whose mortality rates were substantially higher in individuals with type 2 diabetes than in the general population,” they added.
“Persistent inequalities in cancer mortality rates by sociodemographic factors and widening disparities by smoking status suggest that tailored cancer prevention and detection strategies are needed,” they said. “For example, some subgroups such as smokers experienced not only higher mortality rates but also increasing mortality trends during the study period.”
For the population-based study, the researchers drew upon data on 137,804 newly diagnosed adults, ages 35 and older, with type 2 diabetes in the Clinical Practice Research Datalink. Those with type 1 diabetes were excluded.
The average BMI was 30.6, 55% were men, and 83% were white. Nearly half were nonsmokers and about a third were ex-smokers.
The study was funded by Hope Against Cancer.
Ling disclosed no relationships with industry. Co-authors disclosed relationships with AstraZeneca, Novartis, Novo Nordisk, Sanofi-Aventis, Lilly, Merck Sharp & Dohme, Boehringer Ingelheim, Bayer, Pfizer, Medtronic, ShouTi Pharma, and Napp Pharmaceuticals.
Source Reference: Ling S, et al “Inequalities in cancer mortality trends in people with type 2 diabetes: 20 year population-based study in England” Diabetologia 2023; DOI: 10.1007/s00125-022-05854-8.