AHA Abstract Wrap-up: Smoking, Cessation, and TV Behavior
Three abstracts from AHA 2018 shed light on long-term impacts of smoking (and cessation) on CV disease and how CV disease influences sedentary behavior.
Lifetime history of smoking, cessation and the risk of cardiovascular disease: prospective results from the Framingham Heart Study
Smoking Cessation Improves CVD Risk, Slowly. While quitting smoking does confer reduced risk for cardiovascular disease, the results are not as rapid as common belief may hold. Given the growing population of ex-smokers, the authors set out to benchmark both short- and long-term risk in this group.
Methods and Results. Authors tapped data on original and offspring participants in the Framingham Heart Study, all withouth CV disease at start. In 2014, 71% of recorded CV events occurred in smokers with history of >20 pack-years. Former smokers experienced 38% CVD risk reduction relative to current smokers within 5 years of quitting. However, CV risk for ever-smokers who quit didn’t substantially match those of never-smokers until after 15 years.
Take Home Points:
- While substantial CV benefits occur soon after quitting smoking, heavy smokers remain at increased risk of CVD for more than a decade after cessation.
- Screen former smokers for development of CVD even in the absence of other risk factors
- Results support long-established goal of smoking cessation for all patients as a part of a holistic strategy for risk reduction.
Impact of past and current smoking on mortality risk in angiographied coronary patients with type 2 diabetes
Current Smoking Predicts Mortality Regardless of Diabetes Status. Study authors sought to determine the impact of smoking on mortality risk while taking into account other CV risk factors in those with established coronary disease as indicated by coronary angiography.
Study Methods and Results.Current smoking independently predicted CV events after multivariate adjustment including baseline CAD in patients both with and without T2DM. Past smoking not associated with CV events in either patients with T2DM or in non-diabetic subjects. Current smoking was equally predictive of mortality in patients with T2DM and in non-diabetic subjects.
Take Home Points:
- Even in absence of risk factors (eg, type 2 diabetes), significant risk for CVD and death related to cigarette smoking persists.
- Current results do not suggest T2DM patients are not at risk for CV events-only that current smoking is associated with CV events whether a patient has diabetes or not.
CV Risk Factors Contribute to Injurious Amounts of Sedentary Behavior. Since CV risk factors may affect activity levels, the authors wondered if CV risk factors affect the prevalence of detrimental amounts of sedentary behavior. They used duration of TV watching as a measure of sedentary behavior. Hypothesis: CV risk factors would predict prevalence of watching television for extended periods of time.
Methods and Results. TV4 prevalence was 15.65%; independent association with TV4 prevalence remained for all CV risk factors after adjustments. Age >35 yrs associated with less TV watching while CV risk factors obesity, depression, hypertension, and sleep disturbances were all associated with more TV watching.
Take Home Points
- Clinicians rightfully associate sedentary lifestyle with increased CV risk but until now haven’t considered how CV risk factors may perpetuate sedentary behavior.
- Patients should be regularly screened for depression and sleep disturbances and encouraged to participate in regular activity appropriate for their level of health.
- While it is tempting to postulate a self-perpetuating loop, ie, sedentary behavior leads to CV disease which then further limits activity, clinicians should be cautious about this assumption until more evidence is available.
Final Thoughts
- The 3 studies highlighted reinforce our secure knowledge and long-held beliefs that lifestyle plays an important role in the development of CVD-and in its avoidance.
- We need to keep talking to our patients; there is no level of smoking that can be interpreted as “less harmful” and cessation is the ultimate goal at any disease stage.
- Regular exercise is an essential mitigating factor against CV risk and all cause mortality.
- Lifestyle modification has a significant role to play in the prevention and treatment of nearly every disease we face.
Three abstracts published in the current issue of Circulation and in association with the American Heart Association Scientific Sessions 2018 provide updates on how smoking cessation and activity levels affect cardiovascular risk and mortality.In the first study, Meredith Duncan and colleagues found that while significant reductions in CVD occur within 5 years of quitting smoking it may take over 15 years to reach the risk of the general non-smoking population.In the second study, Christoph Saely and colleagues found that current but not past smoking strongly increased mortality risk in angiographied coronary patients with and without type 2 diabetes.And, in the third study, Lucas Helal and fellow researchers found an independent link between sedentary behavior and cardiovascular risk factors.Thumb through the slides below for details on these studies and take-home points for clinical practice.
