Angiotensin converting enzyme inhibitors (ACEIs) are associated with an increased risk of lung cancer compared with angiotensin receptor blockers (ARBs), results of a study published in The BMJ show (24 October 2018)
The research used general practice data on 992,061 people in the UK who began taking antihypertensive medicine between 1995 and the end of 2015. Follow-up was between 1 and 20 years (mean 6.4 years), during which time there were 7,952 cases of lung cancer.
Compared with ARBs, ACEIs were associated with a 14% increased risk of lung cancer (1.2 vs. 1.6 per 1,000 person-years). This risk increased with duration of use, rising to 22% at five years and 31% at ten years.
The researchers explained that biological evidence has suggested that ACEIs could increase the risk of lung cancer because they lead to an accumulation of bradykinin, which has been reported to stimulate growth of lung cancer, and substance P, which has been associated with tumour proliferation and angiogenesis, in the lung. However, they said that there is a lack of clear evidence from observational studies.
They concluded: “Although the magnitudes of the observed estimates are modest, these small relative effects could translate into large absolute numbers of patients at risk for lung cancer, so these findings need to be replicated in other settings.”
 Hicks B, Filion K, Yin H et al. Angiotensin converting enzyme inhibitors and risk of lung cancer: population based cohort study. BMJ 2018;363:k4209. doi: 10.1136/bmj.k4209