Cancer Risk Among Overweight and Obese Adults: The Role of Age, Geography, and Comorbidities in Vulnerable Populations
Anna R Luaces, Tricia Gangoo-Dookhan, Latrice Roebuck, Jazz-Lynn Butler, Jun WuAbstract
Background
Obesity is a critical global health burden and a modifiable determinant of chronic disease, including cardiovascular conditions, type 2 diabetes mellitus (T2DM), sickle cell disease (SCD) related complications, and various malignancies. As survival among individuals with SCD has improved, there has been a growing recognition of cardiometabolic comorbidities within this population, with obesity potentially exacerbating disease severity through inflammatory, vascular, and metabolic pathways. Large cohort studies and meta-analyses consistently show a positive correlation between excess weight and increased incidence of cancer. However, inconsistencies remain due to differences in cancer classification, population characteristics, and methodology. Continued research is warranted to elucidate the mechanistic pathways and contextual factors underlying these associations, particularly in high-risk populations such as individuals with SCD. In addition to individual-level risk factors, social and geographic determinants, such as ZIP code, may influence cancer risk through differences in healthcare access, environmental exposures, and structural barriers to care. Understanding the interplay between obesity and geographic factors is critical for informing targeted, population-level interventions aimed at reducing cancer burden. This study examined the association between clinically diagnosed overweight and obesity, geographic factors and subsequent cancer risk among enrollees of a managed care organization based in South Florida.
Methods
A retrospective cohort study was conducted using data from a managed care plan. Of 8,884 members enrolled between January 1, 2019, and December 31, 2023, 779 were excluded based on eligibility criteria, yielding a final sample of 8,105. Demographics and diagnostic codes were extracted in August 2025 from HorizonODS, ClinicalPerformance, and EPIC. Members were stratified into two cohorts: those with a documented diagnosis of overweight or obesity (n = 2,219) and those without (n = 5,886). Zip codes were grouped based on their corresponding county. The index date was defined as the initial diagnosis of overweight or obesity. Incident cancer diagnoses were assessed with at least one year following the index date.
Results
Overall, 6.9% of individuals with overweight or obesity developed cancer compared to 6.1% in those without (p = 0.156). Among weight categories, overweight individuals exhibited a higher proportion of cancer (7.8%) than those with obesity (6.4%), though this difference was not statistically significant (p = 0.156). Multivariable logistic regression analysis adjusting for follow-up duration revealed no significant relationship between cancer risk and weight status, zip code and race. In contrast, age and diabetes status were associated with cancer occurrence. Compared to the age group (18-44 years), the likelihood of developing cancer was significantly elevated in the age group (45-64 years, OR = 10.4, 95% CI: 7.88-13.9) and the age group (≥ 65 years, OR = 26.7, 95% CI: 20.1-35.6). Additionally, diabetes, hypertension, and dyslipidemia were each associated with approximately two-fold increased odds of cancer (OR 1.92 [1.70–2.17], 2.13 [1.94–2.37], and 2.27 [1.62–3.14], respectively). Sickle cell disease was not significantly associated with cancer risk (OR 0.85, 95% CI 0.47–1.51). The study population was heavily concentrated in Broward County (93%), consistent with the underlying distribution of the managed care organization’s membership. Despite this geographic concentration, no significant association was observed between location and cancer risk. However, the lack of geographic diversity may have limited the ability to detect potentially meaningful regional differences. Future studies with more geographically diverse populations are warranted to better evaluate the impact of geographic factors on cancer risk.
Conclusions
No significant association was observed between overweight/obesity and cancer incidence in this cohort. However, age emerged as the primary predictor of cancer risk and comorbidities, such as diabetes, hypertension, and dyslipidemia, were significantly associated with an increased odds ratio. While zip code and sickle cell disease were not associated with increased cancer risk. Further longitudinal studies are needed to better characterize the relationship between obesity and cancer risk.