Patients who carried on smoking and failed to adhere to advice on diet and exercise were four times more likely to suffer a further cardiovascular event following acute coronary syndrome.

The OASIS study assessed the benefits of dietary, exercise and smoking interventions on patients who had recently experienced an acute coronary event defined as unstable angina or NSTEMI. The study included 18,809 patients from 41 countries.

Patients reported their adherence to dietary counselling, physical activity, defined as >30min at least 3 times a week, and smoking cessation advice at 30 days. Further data were collected at 90 and 180 days from the index event and MI, stroke, cardiovascular death, and all-cause mortality were recorded over this six-month period.

The results showed that 35% of patients continued to smoke and 29% did not adhere to either the diet or exercise recommendations. Only 30% adhered to both the diet and exercise advice for at least 30 days.

By contrast, 96% of subjects continued to take antiplatelet drugs, 79% statins, and 72% an ACE inhibitor/ angiotensin receptor blocker.

Smoking cessation significantly reduced the risk of MI compared with persistent smoking, odds ratio (OR) 0.57 (95% CI: 0.36-0.89) as did adherence to a diet and exercise regimen OR 0.52 (95% CI: 0.40-0.69). Unsurprisingly, patients who continued to smoke and failed to adhere to the dietary and exercise regimens were significantly more likely to suffer an adverse cardiovascular outcome compared with non-smokers who exercised and followed the dietary advice, OR 3.8 (95% CI: 2.5-5.9). There was no notable difference in drug treatments or other baseline characteristics of those patients who adhered to lifestyle advice compared with those who did not. The authors also observed that good lifestyle behaviours appear to cluster in individuals.

One of the key aims of cardiac rehabilitation is to modify the lifestyle behaviour of patients following a coronary event. Encouraging healthy eating and more exercise along with helping patients to stop smoking is central to the process. The OASIS study provides more support for this approach.

The study has shown the short-term benefits of lifestyle change post coronary event and also that patients are much less likely to follow advice on smoking, diet, and exercise than they are to comply with a drug regimen.