We know that smoking is bad for people. Several of my patients steadfastly resolved to give up smoking in the New Year; however, I note that many have failed already. The study by Pan et al (summarised alongside) is a meta-analysis of 89 large cohort studies, specifically in people with diabetes, comparing mortality in smokers, non-smokers and, most interesting of all, ex-smokers. The mortality studies alone had 1 132 700 participants with 109 966 mortality events. This is by far the largest such analysis reported. The data were adjusted for average age which, although not clearly stated, can be assumed to be “middle-aged” from the discussion.
As expected, smoking was associated with an increase in total mortality. The excess risk was 55% for all-cause and 49% for cardiovascular (CV) mortality. Coronary heart disease (CHD) risk was increased by 51% and stroke risk by 54%. The excess risk of peripheral vascular disease was 115% and for heart failure it was 43%.
The good news is that former smokers of relatively short duration had a significant reduction in the relative risk of mortality and CV events in comparison to current smokers. The excess risk in former smokers was attenuated to only 19% for total mortality, 15% for CV mortality, 9% for total CV disease and 14% for CHD. There was no significant increase in stroke risk.
The authors estimate that 14.6% of deaths in men and 3.3% in women with diabetes worldwide were attributable to smoking. These figures were likely to be an underestimation given the methodology behind them.
Hopefully, the benefits of smoking cessation can be given a further fillip with this report. The results should be persuasive for our patients with diabetes and encourage healthcare professionals to redouble their efforts to help them quit smoking.
Smoking is commonly associated with other unhealthy lifestyle factors such as poor diet, excessive alcohol intake and physical inactivity (Chiolero et al, 2006). Other papers attest to continued attention to these factors. Intriguingly, and perhaps comfortingly, the article by Gepner et al (summarised on the next page) indicates that moderate alcohol consumption does not increase CV risk and indeed may be slightly protective. The dose in this study was only 1–2 units per day, which is at the level of the upper limit of 14 units per week recently recommended by the Chief Medical Officer (Department of Health, 2015).
To read the article summaries, please download the PDF
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