When it comes to smoking cessation, it’s clear that “the sooner the better”. But how soon is “soon” and what additional benefits does it confer? Moreover, after a life-threatening, oftentimes traumatic cardiovascular event, does a smoker necessarily have to go the extra mile to quit smoking while keeping himself afloat amidst a wave of new medication regimes and a heightened sense of insecurity?
In part 2 of this four-part series on smoking cessation, we summarise the last two sets of evidence for smoking cessation after cardiovascular events. With data drawn from more recent studies as compared to those seen in Part 1, we hope that there’ll be clearer insight and more applicable data points that we as HCPs could probably use to steer us, and our patients onwards in our journey towards smoking cessation.
STUDY 3: Association of diet, exercise, and smoking modification with risk of early CV events after ACS.1 Giallaluria, F et al. (2010)
Population:
4,254 smokers (≥ 1 cigarette/day, ≥ 1 month), aged ≥ 60, from 41 countries comprising both high-income and middle to low-income economies for a follow-up period of 6 months.
Intervention:
35.2% persistent smokers (1,522); 65.8% recent quitters (2,802) defined as within 30 days of ACS
Comparator:
MI, stroke, CV death; and its composite
Outcome:
The broad geographical demographics with which this study was conducted are important because one’s economic disposition can also affect the treatment received, prognosis and life expectancy of an individual.
And apart from studying the effects of smoking cessation, this study also studied the impact of adherence to a healthy diet and exercise.
But coming back to smoking, compared with those who continued, quitters (defined as having quit within 30 days of ACS) halved their odds for a recurrent MI and were 25% less likely to suffer from the composite outcome of MI, stroke and death.
At just 6 months, compared with persistent smokers, recent quitters had an OR (from fully adjusted models) of 0.57 (95% CI 0.36-0.89; p=0.0145) for MI and an OR of 0.74 (95% CI, 0.53-1.02; p = 0.0698) for the composite of MI/stroke/death.
And these results were reported at the 6-month mark of follow-up, showing that apart from the favourable long-term outlook, smokers can look forward to benefiting from their actions much earlier, especially when it comes to reducing the risk of recurrent myocardial infarction.
STUDY 4: The prognostic significance of Smoking Cessation after ACS.2 Yudi. MB et al. (2017)
Population:
9,375 Australians post-PCI for ACS, consisting of persistent smokers, recent quitters (30 days post-ACS), ex-smokers (30 days prior to ACS) and non-smokers, for a period of 12 months.
Intervention:
14.1% persistent smokers (1,323); 17.2% recent quitters (1,612); 39.6% ex-smokers (3.712); 29.1% non-smokers (2,728)
Comparator:
Survival; mortality, MI, stroke, MACCE
Outcome:
This study, and the most contemporary of the lot, draw results which are probably the most applicable to the population we see now. It studied patients post-PCI for ACS with optimal medical management. A big thing to take away would be that the mean age for those who have quit before, or never smoked before an ACS event occurred, was much older with a mean age of 67. Whereas those who quit after the ACS event, or choose to continue smoking, were much younger at 56 – a 9-year age gap.
In this study, the calculated mortality hazard between quitters and lifelong non-smokers also seemed to be indistinguishable at the 4-year mark.
Results-wise, only persistent smokers were associated with an increased hazard ratio, which translates to an almost twofold increase in long-term mortality.
Being an ex-smoker (HR 1.03, 95% CI 0.87 to 1.22) or a quitter (HR 1.27, 95% CI 0.96 to 1.67) was not associated with an increased hazard for mortality compared with non-smokers, but being a persistent smoker was associated with increased hazard (HR 1.78, 95% CI 1.36 to 2.32).
In summary, these are the few pertinent points that we can all take back with us:
- For patients who have suffered from a cardiovascular event, by quitting, it is possible to halve their risk of a subsequent heart attack in just 6 months – giving them a short-term goal to work towards.
- When looking at the long-term benefits, in 4 years, their chance of survival is similar to that of a lifelong non-smoker.
- Whereas, if a smoker chooses to continue smoking, they now have twice the risk of their non-smoking counterparts suffering from a cardiovascular-related death with a history of their previous episode.
Follow our social media channels linked below, to get the latest updates on the part of the next part of this series on smoking cessation where we’ll be going through some of the more common pharmacological therapies available.
References:
- Giallauria F, Vigorito C. [Association of diet, exercise, and smoking modification with risk of early cardiovascular events after acute coronary syndromes]. Monaldi Arch Chest Dis. 2010;74(1):44-6.
- Yudi MB, Farouque O, Andrianopoulos N on behalf of the Melbourne Interventional Group, et al. The prognostic significance of smoking cessation after acute coronary syndromes: an observational, multicentre study from the Melbourne interventional group registry. BMJ Open 2017;7:e016874. doi: 10.1136/bmjopen-2017-016874
