Among 65,990 Spanish adults tracked from 2011 through December 2023, roughly 1 in 5 individuals diagnosed with either asthma (21.3%) or COPD (21.8%) continued smoking—a striking rate given the direct harm to already-compromised airways. Current smokers with asthma faced a 70% higher all-cause mortality risk compared to former smokers (RR=1.70; 95% CI: 1.16–2.51), while those with COPD carried a 34% excess risk (RR=1.34; 95% CI: 1.07–1.67). Sustained smoking correlated with being female, younger, sedentary, and having lower educational attainment, whereas Mediterranean diet adherence, marriage, and overweight/obesity status were protective against continued smoking.
The mortality differentials here are clinically significant and underscore a persistent implementation gap: cessation is guideline-endorsed yet roughly one-fifth of this high-risk cohort continues smoking regardless. The finding that Mediterranean diet adherence associates with quitting—independent of other factors—adds a behavioral-clustering dimension worth exploring in cessation program design. The female-and-younger risk profile challenges the assumption that younger patients self-correct after diagnosis. Limitations include self-reported smoking and disease status, potential survey non-response bias, and the observational design precluding causal inference. Residual confounding from disease severity data—absent here—could partly explain mortality differences. Still, the large nationally representative cohort and decade-long follow-up make this confirmatory evidence with actionable precision: cessation interventions must be sociodemographically tailored, not generic.