Pioglitazone and lung cancer risk in Taiwanese patients with type 2 diabetes

Metformin in Chemoprevention of Lung Cancer: A Retrospective Population-Based Cohort Study in Lithuania

Background and Objectives: This study aimed to evaluate the potential chemopreventive effect of antidiabetic medications, specifically metformin and pioglitazone, on lung cancer in patients with type 2 diabetes mellitus (T2DM). Additionally, the potential dose-response relationship for metformin use was analyzed. Methods: We conducted a retrospective cohort study utilizing comprehensive national health insurance and cancer registry databases to gather a large cohort of T2DM patients. Cox proportional hazards regression models were used to assess the risk of lung cancer across different antidiabetic medication groups, adjusting for potential confounders such as age and gender. A dose-response analysis was conducted for metformin users. Results: Our results indicated that metformin users had a significantly lower lung cancer risk than the reference group (HR = 0.69, 95% CI [0.55-0.86], p = 0.001). The risk reduction increased with higher cumulative metformin doses: a metformin cumulative dose between 1,370,000 and 2,976,000 had an HR of 0.61 (95% CI [0.49-0.75], p < 0.001) vs. cumulative metformin dose >2,976,000 which had an HR of 0.35 (95% CI [0.21-0.59], p < 0.001). No significant association between pioglitazone use and the risk of lung cancer was found (HR = 1.00, 95% CI [0.25-4.02]). Conclusions: This study shows that metformin may have a dose-dependent chemopreventive effect against lung cancer in T2DM, while the impact of pioglitazone remains unclear and requires further investigation.

Causal relationship between type 2 diabetes and common respiratory system diseases: a two-sample Mendelian randomization analysis

Background

Type 2 diabetes (T2D) frequently co-occurs with respiratory system diseases such as chronic obstructive pulmonary disease (COPD), bronchial asthma, lung cancer, interstitial lung disease, and pulmonary tuberculosis. Although a potential association is noted between these conditions, the available research is limited.

Objective

To investigate the causal relationship between patients with T2D and respiratory system diseases using two-sample Mendelian randomization analysis.

Methods

Causal relationships were inferred using a two-sample Mendelian randomization (MR) analysis based on publicly available genome-wide association studies. We employed the variance inverse-weighted method as the primary analytical approach based on three key assumptions underlying MR analysis. To bolster the robustness and reliability of our results, we utilized MR Egger's intercept test to detect potential pleiotropy, Cochran's Q test to assess heterogeneity, funnel plots to visualize potential bias, and "leave-one-out" sensitivity analysis to ensure that our findings were not unduly influenced by any single genetic variant.

Result

The inverse variance weighted (IVW) analysis indicated a causal relationship between T2D and COPD [Odds Ratio (OR) = 0.87; 95% Confidence Interval (CI) = 0.82-0.96; p < 0.05]. No significant heterogeneity or pleiotropy were observed through their respective tests (p > 0.05), and the statistical power calculations indicated that the results were reliable. The IVW analysis showed a negative causal relationship between T2D and bronchial asthma [OR = 0.85; 95% CI = 0.81-0.89; p < 0.05]. However, the IVW under the random-effects model indicated heterogeneity (p < 0.05), suggesting instability in the results and requiring cautious interpretation. The study found a positive causal relationship between T2D and pulmonary tuberculosis (OR = 1.24, 95% CI = 1.05-1.45, p < 0.05). However, they exhibited pleiotropy (p < 0.05), indicating their instability. No correlation between T2D and interstitial lung disease or lung cancer was observed.

Conclusion

T2D is negatively associated with COPD, suggesting that T2D may reduce the risk of developing COPD. A negative causal relationship between T2D and bronchial asthma has been observed, but the results exhibit heterogeneity. There is a positive causal relationship between T2D and pulmonary tuberculosis, yet the findings suggest the presence of pleiotropy. No significant causal relationship between T2D and lung cancer or interstitial lung disease was observed.

Associations of glycosylated hemoglobin, pre-diabetes, and type 2 diabetes with incident lung cancer: A large prospective cohort study

BACKGROUND

The association of pre-diabetes and type 2 diabetes (T2D) with incident lung cancer is uncertain, and the incident risk across the glycemic spectrum is unclear. We aimed to explore the associations of glycosylated hemoglobin (HbA1c), pre-diabetes, and T2D with incident lung cancer in a large prospective cohort.

METHODS

Leveraging a total of 210,779 cancer-free adults recruited in the UK Biobank between 2006 and 2010. We performed multivariable Cox proportional hazards models and restricted cubic spline methods to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for the associations of HbA1c, pre-diabetes, and T2D with incident lung cancer.

RESULTS

During a median follow-up of 11.06 years, 1738 incident lung cancer cases were ascertained. The incidence of lung cancer was 20% higher among people with diabetes (HR: 1.20, 95% CI: 1.02 to 1.42) and 38% higher among people with pre-diabetes (HR: 1.38, 95% CI: 1.15 to 1.65). After dividing people with diabetes by whether taking antidiabetic medications, the incidence was 28% higher among people with diabetes without medications (HR: 1.28, 95% CI: 1.02 to 1.61) and 15% higher among people with diabetes with medications (HR: 1.15, 95% CI: 0.93 to 1.41). The increased risk of incident lung cancer for each standard deviation (6.45 mmol/mol) increase in HbA1c was more pronounced across HbA1c values of 32-42 mmol/mol (HR: 1.37, 95% CI: 1.18 to 1.59). The risk was more pronounced among participants <60 years.

CONCLUSIONS

Pre-diabetes and T2D are associated with an increased incidence of lung cancer. The increased risk of incident lung cancer is more pronounced across HbA1c values of 32-42 mmol/mol, which are currently considered normal values.

Pioglitazone and breast cancer risk in female patients with type 2 diabetes mellitus: a retrospective cohort analysis

BACKGROUND

Whether pioglitazone may affect breast cancer risk in female diabetes patients is not conclusive and has not been investigated in the Asian populations.

METHODS

The reimbursement database of Taiwan's National Health Insurance was used to enroll an unmatched cohort and a propensity score-matched cohort of ever users and never users of pioglitazone in female patients with newly diagnosed type 2 diabetes during 1999-2008. The patients were alive on January 1, 2009 and were followed up for breast cancer incidence until December 31, 2011. Cox regression was used to estimate hazard ratios for ever users and tertiles of cumulative duration of pioglitazone therapy versus never users, and for cumulative duration of pioglitazone therapy treated as a continuous variable. Three models were created for the unmatched cohort and the matched cohort, respectively: 1) without adjustment for covariates; 2) after adjustment for covariates that differed with statistical significance (P-value < 0.05) between ever users and never users; and 3) after adjustment for all covariates.

RESULTS

There were 174,233 never users and 6926 ever users in the unmatched cohort; and 6926 never users and 6926 ever users in the matched cohort. After a median follow-up of 2.8 years, the numbers of incident breast cancer were 1044 in never users and 35 in ever users in the unmatched cohort and were 41 and 35, respectively, in the matched cohort. Hazard ratios suggested a null association between pioglitazone and breast cancer in all three models in either the unmatched cohort or the matched cohort. The overall hazard ratio after adjustment for all covariates was 0.758 (95% confidence interval: 0.539-1.065) in the unmatched cohort and was 0.824 (95% confidence interval: 0.524-1.296) in the matched cohort. None of the hazard ratios for the tertiles of cumulative duration of pioglitazone therapy and for the cumulative duration being treated as a continuous variable were statistically significant.

CONCLUSIONS

This study suggests a null association between pioglitazone and breast cancer risk in female patients with type 2 diabetes mellitus. However, because of the small breast cancer cases and the limited follow-up time, further studies are warranted to confirm our findings.

Pioglitazone and Risk of Chronic Obstructive Pulmonary Disease in Patients with Type 2 Diabetes Mellitus: A Retrospective Cohort Study

BACKGROUND

Pioglitazone's effect on chronic obstructive pulmonary disease (COPD) has rarely been studied.

PURPOSE

This retrospective observational study investigated whether the use of pioglitazone would affect the risk of COPD in patients with type 2 diabetes mellitus.

PATIENTS AND METHODS

The Taiwan's National Health Insurance database was used to enroll 9487 matched pairs of ever users and never users of pioglitazone based on propensity score from a cohort of 350,536 patients. The enrolled patients had a new diagnosis of type 2 diabetes mellitus between 1999 and 2008 and were not having a diagnosis of COPD before January 1, 2009. They were then followed up for COPD, starting from January 1, 2009 until December 31, 2011. Diagnosis of COPD was based on the codes of 491 for chronic bronchitis and 492 for emphysema based on the International Classification of Diseases, Ninth Revision, Clinical Modification. Cox regression was used to estimate hazard ratios. The interactions between pioglitazone and COPD risk factors including pneumonia, pulmonary tuberculosis and tobacco abuse were also investigated.

RESULTS

In 9487 never users and 9487 ever users of pioglitazone, the case numbers of incident COPD were 359 and 295, respectively. The respective incidence rates of COPD were 1484.73 and 1167.61 per 100,000 person-years. The overall hazard ratio (95% confidence interval) for COPD that compared ever to never users was 0.778 (0.667-0.908). The hazard ratios for the tertiles of cumulative duration of pioglitazone therapy (cutoffs: <11.0, 11.0-19.6 and >19.6 months) to never users were 0.904 (0.729-1.121), 0.727 (0.578-0.914) and 0.715 (0.570-0.896), respectively. No interactions between pioglitazone and COPD risk factors including pneumonia, pulmonary tuberculosis and tobacco abuse were noted.

CONCLUSION

Pioglitazone use is associated with a significantly lower risk of COPD.

Association between diabetes mellitus and lung cancer: Meta-analysis

BACKGROUND

This study aimed to summarize the association between diabetes mellitus (DM) and the incidence of lung cancer using a meta-analysis of cohort studies.

MATERIALS AND METHODS

We systematically searched PubMed, Embase and the Cochrane Library to identify potential cohort studies. Relative risk (RR) was used to calculate the association between DM and the risk of lung cancer. Subgroup analysis, sensitivity analysis and test for publication bias were performed. Twenty cohort studies were selected.

RESULTS

The participants with DM showed little or no significant effect on the risk of lung cancer (RR: 1.10; 95% CI: 0.99-1.23; P = .087). DM was not associated with the risk of lung cancer in men (RR: 1.11; 95%CI: 0.92-1.35; P = .270), but a significant association was observed in women (RR: 1.18; 95%CI: 1.10-1.28; P < .001). Subgroup analysis suggested that smoker status was confounding variables that could bias the relationship between DM and the incidence of lung cancer.

CONCLUSIONS

This meta-analysis suggests that DM has no significant impact on the incidence of lung cancer in men but has a harmful effect on women.

Assessing the Current State of Lung Cancer Chemoprevention: A Comprehensive Overview

Chemoprevention of lung cancer is thought to significantly reduce the risk of acquiring these conditions in the subpopulation of patients with underlying health issues, such as chronic obstructive pulmonary disorder and smoking-associated lung problems. Many strategies have been tested in the previous decades, with very few translating to successful clinical trials in specific subpopulations of patients. In this review, we analyze these strategies, as well as new approaches that have emerged throughout the last few years, including synthetic lethality concept and microbiome-induced regulation of lung carcinogenesis. Overall, the continuous effort in the area of lung chemoprevention is required to develop practical therapeutical approaches. Given the inconsistency of results obtained in clinical trials targeting lung cancer chemoprevention in various subgroups of patients that differ in the underlying health condition, race, and gender, we believe that individualized approaches will have more promise than generalized treatments.