Evaluation of TReatment With Angiotensin Converting Enzyme Inhibitors and the Risk of Lung Cancer: ERACER-An Observational Cohort Study.

Introduction: Angiotensin converting enzyme inhibitors (ACEIs) are widely prescribed medications. A recent British study reported a 14% increased risk of lung cancer with ACEI versus angiotensin receptor blocker (ARB) prescriptions, and risk increased with longer use. We sought to validate this observation.

Methods: We searched the Intermountain Enterprise Data Warehouse from 1996 to 2018 for patients newly treated with an ACEI or an ARB and with ≥1 year's follow-up or to incident lung cancer or death. Unadjusted and adjusted hazard ratios (HRs) for lung cancer and for lung cancer or all-cause mortality were calculated for ACEIs compared to ARBs.

Results: A total of 187,060 patients met entry criteria (age 60.2 ± 15.1 y; 51% women). During a mean of 7.1 years follow-up (max: 20.0 years), 3,039 lung cancers and 43,505 deaths occurred. Absolute lung cancer rates were 2.16 and 2.31 per 1000 patient-years in the ARB and ACEI groups, respectively. The HR of lung cancer was modestly increased with ACEIs (unadjusted HR = 1.11, CI: 1.02, 1.22, P = .014; adjusted HR = 1.18, CI: 1.06, 1.31, P = .002; number needed to harm [NNH] 6,667). Rates of the composite of lung cancer or death over time also favored ARBs. Lung cancer event curves separated gradually over longitudinal follow-up beginning at 10-12 years.

Conclusions: We noted a small long-term increase in lung cancer risk with ACEIs compared with ARBs. Separation of survival curves was delayed until 10-12 years after treatment initiation. Although the observed increases in lung cancer risk are small, implications are potentially important because of the broad use of ACEIs. Thus, additional work to validate these findings is needed.