Association between metformin, aspirin and cancer incidence and mortality risk in adults with diabetes
Menée à partir de données portant sur 2 045 patients atteints d'un diabète, cette étude évalue l'association entre l'utilisation de metformine et le risque de cancer ou de décès puis examine l'effet de la metformine sur l'association entre l'utilisation d'aspirine et la mortalité par cancer
BACKGROUND : Metformin and aspirin are commonly co-prescribed to people with diabetes. Metformin may prevent cancer but, in older people, aspirin has been found to increase cancer mortality. This study examined if metformin reduces cancer mortality and incidence in older people with diabetes, and utilized randomization to 100 mg aspirin or placebo in the ASPREE trial to quantify aspirin’s impact within metformin users. METHODS : Analysis included community-dwelling ASPREE participants (70+ years, or
≥
65 years for U.S. minorities) with diabetes. Diabetes was defined as fasting blood glucose level (FBGL) >125mg/DL, self-report of diabetes or antidiabetic medication use. Cox proportional hazards regression models were used to analyze the association of metformin, and a metformin and aspirin interaction, with cancer incidence and mortality with adjustment for confounders. RESULTS : Of 2045 participants with diabetes at enrollment, 965 were concurrently using metformin. Metformin was associated with a reduced cancer incidence risk (Adjusted HR = 0.68, 95% CI 0.51, 0.90), but no conclusive benefit for cancer mortality (Adjusted HR = 0.72, 95%CI 0.43, 1.19). Metformin users randomized to aspirin had greater risk of cancer mortality compared to placebo (HR = 2.53, 95% CI 1.18, 5.43), but no effect was seen for cancer incidence (HR = 1.11, 95% CI 0.75, 1.64). However, the possible effect modification of aspirin on cancer mortality was not statistically significant (interaction P = .11). CONCLUSIONS : In community-dwelling older adults with diabetes, metformin use was associated with reduced cancer incidence. Increased cancer mortality risk in metformin users randomized to aspirin warrants further investigation.
JNCI Cancer Spectrum 2023