Clinical outcomes for smokers with early-onset breast cancer: An analysis of the National Inpatient Sample.

e23358 Background: Despite recent global decreases in overall cancer incidence, the incidence of early-onset breast cancer (EOBC) is steadily increasing globally. Limited data is available on the comorbid correlations for this unfortunately expanding population. We sought to examine the national inpatient sample database to describe in-hospital outcomes among smokers with EOBC. Methods: Data were extracted from the National Inpatient Sample (NIS) Database for 2019 and 2020. The NIS was searched for hospitalizations of adult patients with EOBC, defined as all-cause breast cancer in patients 50 years old or younger. We then examined the outcomes of patients who were noted to be active smokers. Multivariate logistic was used to adjust for confounders. The primary outcome was inpatient mortality and secondary outcomes were annotated accordingly. SPSS software was used for statistical analysis, and all results were powered to p < 0.001. Results: This study included 10,764 patients with EOBC, of which 1667 (15.5%) were smokers. Multivariate regression showed that smoking patients with EOBC had higher inpatient mortality (OR 1.113, CI 1.077-1.150, p < 0.001). On secondary analysis, smokers with EOBC were more likely to have systemic lupus erythematosus (OR 1.104, CI 1.026-1.189), anemia (OR 1.167, CI 1.152-1.183), thrombocytopenia (OR 1.159, CI 1.128-1.191), peripheral artery disease (OR 1.261, CI 1.106-1.438), hypertension (OR 1.172, CI 1.124-1.223), chronic kidney disease (OR 1.137, CI 1.088-1.188), acute renal failure (OR 1.179, CI 1.144-1.215), pancreatitis (OR 1.092, CI 1.018-1.172), mitral regurgitation (OR 1.279, CI 1.137-1.438), pericarditis (OR 1.193, CI 1.125-1.265), severe liver disease (OR 1.164, CI 1.144-1.184), leukemia (OR 1.188, CI 1.035-1.363), lymphoma (OR 1.179, CI 1.020-1.361), all-cause arrhythmias (OR 1.235, CI 1.169-1.306), all-cause shock (OR 1.125, CI 1.049-1.206), all-cause heart block (OR 1.517, CI 1.227-1.876), all-cause sepsis (OR 1.159, CI 1.138-1.180), all-cause coagulopathy (OR 1.165, CI 1.119-1.213), all-cause heart failure (OR 1.174, CI 1.125-1.225), all-cause stroke (OR 1.179, CI 1.123-1.238), and all-cause myocardial infarction (OR 1.228, CI 1.125-1.341). Conclusions: In this nationally representative, population‐based retrospective cohort study, smokers with EOBC were associated with higher mortality and worse outcomes.