JMIR Publications

ABSTRACT

Background:

Given the increased risk for heart failure (HF) posed by type 2 diabetes, defining the effect of smoking cessation for HF in a type 2 diabetes cohort is important.

Objective:

To examine the association between interval changes in smoking behavior and the risk of HF among patients with type 2 diabetes.

Methods:

We identified 365,352 current smokers with type 2 diabetes who had 2 consecutive health screenings (2009–2012) and follow them until December 31, 2018, for the incident HF. Based on smoking behavior changes, participants were categorized into quitter, reducer I (≥50% reduction) and II (<50% reduction), sustainer (reference group), and increaser groups.

Results:

Compared to sustainers, smoking cessation was associated with lower risks of HF (adjusted hazard ratio [aHR] 0.90, 95% confidence interval [CI]=0.86–0.95), whereas increasers showed higher risks of HF than sustainers; heavy smokers who increased their level of smoking had higher HF risks (aHR 1.13, 95% CI=1.04–1.24). In the case of reducers, the risk of HF was not reduced, but rather increased slightly (reducer I, aHR 1.06, 95% CI=1.01–1.11; reducer II, aHR 1.04, 95% CI=1.00–1.08). Consistent results were noted for subgroup analyses including type 2 diabetes severity, age, and sex.

Conclusions:

Smoking cessation was associated with a lower risk of HF among patients with type 2 diabetes, while increasing smoking amount was associated with a higher risk for HF than in those sustaining their smoking amount. There was no benefit from reduction in smoking amount. Clinical Trial: Not applicable.