Metformin use in cancer survivors with diabetes reduces all-cause mortality, based on the Korean National Health Insurance Service between 2002 and 2015

Malignant neoplasms are the leading cause of death in Korea. We aimed to examine if metformin use in cancer survivors reduces all-cause mortality. This study was retrospectively designed based on data from the Korean National Health Insurance Service-National Health Screening Cohort (HEALS) between 2002 and 2015. The Kaplan-Meier estimator and log-rank test was performed to estimate the survival function according to metformin usage (3721 metformin non-users with diabetes, 5580 metformin users with diabetes, and 24,483 non-diabetic individuals). Adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were calculated using Cox proportional hazards regression models.The median follow-up duration was 4.2 years. The HRs (95% CIs) for all-cause mortality of metformin users and the non-diabetic group were 0.762 (0.683-0.850) and 1.055 (0.966-1.152) in men and 0.805 (0.649-0.999), and 1.049 (0.873-1.260) in women, respectively, compared with metformin non-users among diabetic cancer survivors, in a fully adjusted model. After stratifying metformin users into pre- and post-diagnosis of cancers, adjusted HRs (95% CIs) of pre- and post-diagnosis metformin users for all-cause mortality were 0.948 (0.839-1.071) and 0.530 (0.452-0.621) in men and 1.163 (0.921-1.469) and 0.439 (0.323-0.596) in women, respectively.Metformin use in cancer survivors with diabetes reduced overall mortality rates. In particular, metformin use after cancer diagnosis, not before cancer diagnosis, was inversely associated with overall mortality.Active treatment with metformin for diabetic cancer survivors after cancer diagnosis can improve their survival rates.

Risk factors for genital infections in people initiating SGLT2 inhibitors and their impact on discontinuation

INTRODUCTION

To identify risk factors, absolute risk, and impact on treatment discontinuation of genital infections with sodium-glucose co-transporter-2 inhibitors (SGLT2i).

RESEARCH DESIGN AND METHODS

We assessed the relationship between baseline characteristics and genital infection in 21 004 people with type 2 diabetes initiating SGLT2i and 55 471 controls initiating dipeptidyl peptidase-4 inhibitors (DPP4i) in a UK primary care database. We assessed absolute risk of infection in those with key risk factors and the association between early genital infection and treatment discontinuation.

RESULTS

Genital infection was substantially more common in those treated with SGLT2i (8.1% within 1 year) than DPP4i (1.8%). Key predictors of infection with SGLT2i were female sex (HR 3.64; 95% CI 3.23 to 4.11) and history of genital infection; <1 year before initiation (HR 4.38; 3.73 to 5.13), 1-5 years (HR 3.04; 2.64 to 3.51), and >5 years (HR 1.79; 1.55 to 2.07). Baseline HbA1c was not associated with infection risk for SGLT2i, in contrast to DPP4i where risk increased with higher HbA1c. One-year absolute risk of genital infection with SGLT2i was highest for those with a history of prior infection (females 23.7%, males 12.1%), compared with those without (females 10.8%, males 2.7%). Early genital infection was associated with a similar discontinuation risk for SGLT2i (HR 1.48; 1.21-1.80) and DPP4i (HR 1.58; 1.21-2.07).

CONCLUSIONS

Female sex and history of prior infection are simple features that can identify subgroups at greatly increased risk of genital infections with SGLT2i therapy. These data can be used to risk-stratify patients. High HbA1c is not a risk factor for genital infections with SGLT2i.