PS02.01 Use of β-blockers and Risk of Developing Lung Cancer: Topic: Medical Oncology

Abstract

Lung cancer is the leading cause of cancer related mortality strongly linked with smoking. We have recently shown that major stressful life events (e.g. divorce) within past 5 years can increase the risk of developing lung cancer1. We wanted to explore if use of β-blockers which targets endogenous catecholamine is protective against developing lung cancer. In this matched case-control study cases (CA) were lung cancer patients diagnosed within last 12 months. Controls (CO) were patients without prior history of any malignancy. Cases and controls were matched for age, gender and smoking status. Smokers had at least 10 packs/years history of smoking. Data was collected using standardized research questionnaire and stored electronically. Primary endpoint was odds of having a major stressful life event between cases and controls. Secondary end point was odds of β -blockers use amongst cases and controls. Information was collected on 11 major stressful life events based on Holmes-Rahe stress scale. A sample of 360 patients (120 cases and 240 controls), were needed to achieve 80% power to detect an odds ratio of 2.00 versus the alternative of equal odds using Chi-Square test with a 0.05 significance level. The study was performed after obtaining institutional review boards approval at each institution. Between May 2015 and December 2016 a total of 324 patients were enrolled (23 were excluded due to prior history of cancer). Of those 301 (CA = 102; CO= 199) were included for final analysis. The two groups were well matched in median age (CA=64.4 years; C0 =63.9years), gender (CA-Male=48%; CO-Male=49.2%) and smoking status (Ever smoker, CA=86%; CO=85%). Lung cancer patients were significantly more likely to have a major stressful event within past 5 years as compared to controls (CA=77.4% vs CO=65.8%, p-value=0.03, (Odds ratio=1.78). Serious life-threatening illness of an immediate family member (p=0.04) and retirement (p=0.07) with in last 5 years were more common among cases. Use of β –blockers was significantly higher amongst controls (CA=29.4%;CO=49.7%), p-value=0.0007, OR=0.42.On Multi-variate analysis use of β –blockers remained significant (p=0.0014).Early stage lung cancer patients (Stage I and II) were also more likely to be on β –blockers (44%) than late stage patients (Stages III and IV) (26%), though difference was not statistically significant p=0.125 perhaps due to small sample size. β-blockers by targeting systemic catecholamines may reduce the chance of lung cancer development as well as its progression. Protective effect of β-blockers against lung cancer should be confirmed in future studies.