In a U.S. cross-sectional study reported in JACC:CardioOncology, Ganatra et al found that mortality from comorbid cancer and cardiovascular disease was significantly higher in counties with higher vs lower social vulnerability (ie, age greater than vs less than 45, male vs female sex, Black vs White race, and in persons living in rural vs metropolitan areas).
Study Details
The study used the Centers for Disease Control and Prevention (CDC) Wide-Ranging Online Data for Epidemiologic Research database for 2015 to 2019 to obtain county-level data on mortality attributed to cancer, cardiovascular disease, and comorbid cancer and cardiovascular disease. County-level social vulnerability index data for 2014 to 2018 from the CDC Agency for Toxic Substances and Disease Registry were used to generate social vulnerability index percentiles and quartiles (lower quartile = greater social vulnerability). Age-adjusted mortality rates for 2015 to 2019 were estimated and analyzed according to social vulnerability index quartiles.
Age-Adjusted Mortality Rates
The overall age-adjusted mortality rate for cancer was 167.80 (95% confidence interval [CI] = 167.62–167.99) per 100,000 person-years. The age-adjusted mortality rate per 100,000 person-years was lowest in the first social vulnerability index quartile (160.11, 95% CI = 159.69–160.52) and highest in the fourth social vulnerability index quartile (174.09, 95% CI = 173.70–174.49); the difference yielded an excess of 13.98 deaths per 100,000 person-years for the fourth vs first quartiles (rate ratio [RR] for fourth vs first quartiles = 1.087, 95% CI = 1.084–1.091).
The overall age-adjusted mortality rate for cardiovascular disease was 386.01 (95% CI = 385.73–386.29) per 100,000 person-years. The age-adjusted mortality rate per 100,000 person-years was lowest in the first quartile (344.25, 95% CI = 343.63–344.86) and highest in the fourth quartile (443.13, 95% CI = 442.49–443.77); the difference yielded an excess of 98.88 deaths per 100,000 person-years in the fourth vs first quartiles (RR = 1.287, 95% CI = 1.284–1.290).
The overall age-adjusted mortality rate for comorbid cancer and cardiovascular disease was 47.75 (95% CI = 47.66–47.85) per 100,000 person-years. The age-adjusted mortality rate per 100,000 person-years was lowest in the first quartile (43.47, 95% CI = 43.25–43.69) and highest in the fourth quartile (58.25, 95% CI = 58.02–58.48); the difference yielded an excess of 10.5 deaths per 100,000 person-years in the fourth vs first quartiles (RR = 1.34, 95% CI = 1.33–1.35). This rate ratio was significantly greater than rate ratios observed for the age-adjusted mortality rate for cancer alone (P < .001) or cardiovascular disease alone (P < .001).
Analysis by Race in the Lowest Social Vulnerability Index Quartile
In a sensitivity analysis by race within the fourth social vulnerability index quartile, with White patients as the reference group, Black patients alone had significantly greater rate ratios for cancer mortality (1.139, 95% CI = 1.132–1.146), cardiovascular disease mortality (1.230, 95% CI = 1.225–1.234), and comorbid cancer and cardiovascular disease mortality (1.142, 95% CI = 1.131–1.154).
Groups With Comorbid Cancer and Cardiovascular Disease With Greatest Relative Increases in Risk
According to age, sex, race, and ethnicity, the groups with the greatest relative increases in mortality from comorbid cancer and cardiovascular disease between the first and fourth social vulnerability index quartiles compared with their counterparts were adults aged < 45 years (RR = 2.02, 95% CI = 1.92–2.12), women (RR = 1.36, 95% CI = 1.34–1.37), Asian/Pacific Islanders (RR = 2.17, 95% CI = 2.08–2.26), and Hispanic patients (RR = 1.22, 95% CI = 1.21–1.23). No marked differences in rate ratios according to urban or rural status were observed.
The investigators concluded: “Comorbid cancer and cardiovascular disease mortality increased in counties with higher social vulnerability. Improved education, resource allocation, and targeted public health interventions are needed to address inequities in cardio-oncology.”
Sarju Ganatra, MD, of the Cardio-Oncology Program, Division of Cardiovascular Medicine, Lahey Hospital & Medical Center, Burlington, Massachusetts, is the corresponding author of the JACC:CardioOncology article.
Disclosure: The study was supported by the National Cancer Institute, Catherine Fitch Fund, and Gelb Master Clinician Fund at Brigham and Women’s Hospital. For full disclosures of the study authors, visit jacc.org.
