28 May, 14 | by BMJ
At the end of last year, the US Preventive Services Task Force launched guidelines recommending screening for lung cancer in those at high risk. These were greeted with applause by some and dismay by others. In yesterday’s State of the Art Review, Canadian authors Tammemagi and Lam discuss the evidence for and against. Yes, there is evidence that screening for lung cancer with low dose computed tomography can reduce mortality from the disease by 20% in high risk smokers (those aged 55-74 years who’ve smoked at least 30 pack years and former smokers who quit in the last 15 years). But consider the possible harms: false positives, overdiagnosis, psychological stress, and exposure to excess radiation.
These authors also point out that cost effectiveness analyses—based on modelling—vary in their findings, and there are uncertainties around the optimal frequency and duration of screening. Risk prediction tools to identify those at high risk do exist, but are still being refined, as are risk calculators to help us decide what to do with screen detected lung nodules.
Their own conclusion is that lung cancer screening programs are worth trialling in select samples, in a staged fashion, with careful evaluation of the emerging data. And clearly the jury’s still out in many other countries, including the UK.
However, while lung cancer is the leading cause of death from cancer worldwide, cardiovascular disease remains the leading killer overall. The polypill remains one attractive means to tackle this, and a randomised controlled trial, set in real life general practices in New Zealand, shows—yet again—that it improves adherence. In this trial of 513 adults with established cardiovascular disease or five year risk ≥15%, adherence with the polypill (aspirin, simvastatin, lisinopril, and either atenolol or hydrochlorothiazide) at 12 months was 81%, compared to 46% with usual care (relative risk 1.75, 95% confidence interval 1.52 to 2.03).
So why isn’t this routine clinical practice? Well, as the triallists and our editorialist Huffman point out, the polypill is no panacea. In this trial, cardiovascular events, serious adverse events, and reductions in blood pressure or lipid levels were not significantly different to usual care. Furthermore, over a third of those taking the polypill stopped taking it, with common reasons being “medical practitioner decision” and side effects. So we clearly still need to know how best to use (or switch to) these drugs, and to engage patients—and prescribers—when making these decisions.
And for something probably less controversial, turn to our Clinical Review on the management of cutaneous viral warts. Warts are common and most resolve spontaneously, but for those that don’t, here’s a refresher on what works best, and a peek at what’s in the pipeline.
Mabel Chew is practice editor, The BMJ.