Association Between Metformin Use and Mortality Among Individuals With Non-Small Cell Lung Cancer Receiving Immune...

Area of Science:

• Oncology
• Pharmacology
• Epidemiology

Background:

• Immune checkpoint inhibitors (ICI) are a key treatment for non-small cell lung cancer (NSCLC).
• Metformin's potential synergistic effect with ICI in NSCLC warrants investigation.
• Understanding the impact of antidiabetic medication on NSCLC patient outcomes is crucial.

Purpose of the Study:

• To evaluate the association between metformin use and mortality in NSCLC patients initiating ICI therapy.
• To compare metformin monotherapy with sulfonylurea and/or DPP-4 inhibitors in this patient population.
• To assess the impact on cancer-specific and all-cause mortality.

Main Methods:

• Retrospective cohort study using SEER-Medicare data (2013-2019).
• Inclusion of NSCLC patients with type 2 diabetes initiating ICI and prior antidiabetic use.
• Stabilized inverse probability of treatment weighting (sIPTW) for confounder adjustment.
• Fine-Gray competing risk and Cox proportional hazards models for mortality analysis.

Main Results:

• 1123 metformin users and 362 sulfonylurea/DPP-4 users were analyzed after weighting.
• No significant difference in cancer-specific mortality: aIR difference=1 (95% CI: -13 to 16).
• No significant difference in all-cause mortality: aIR difference=4 (95% CI: -6 to 15).
• Metformin use showed no significant association with cancer-specific (aHR=1.08) or all-cause mortality (aHR=1.07).

Conclusions:

• Metformin use was not significantly associated with improved cancer-specific or all-cause mortality in NSCLC patients treated with ICI.
• Findings suggest no survival benefit or detriment from metformin in this specific context.
• Further research may explore other antidiabetic agents or patient subgroups.