Prospective Study of Incidence and Impact of Comorbidities on Breast Cancer Survival from India

Purpose: To report comorbidity burden in newly-diagnosed treatment-naïve breast cancer patients and its effect on survival.

Methods: Prospective observational study in which demographic, comorbidity and outcome data from a consecutive cohort of patients diagnosed and treated between September 2019 to September 2021 were collected. Charlson Comorbidity Index (CCI) score was calculated for all and proportion of each comorbidity was determined at diagnosis (baseline), at conclusion and six-months post-treatment. Univariate and multivariate analysis was done for impact of various demographic and disease-related factors on the incidence of comorbidities as well as on progression free survival (PFS) and overall survival (OS).

Results: Out of five hundred patients who consented for the study, 416 patients completed planned treatment and only 206 patients had physical follow-up due to COVID-19 pandemic. Incidence of comorbidity at the three time-points was 24%, 32% and 26% respectively. The difference was significant compared to baseline at both the time-points (p<0.05). Hypertension and diabetes were the most common types (incidence 15%-21% and 12-18% respectively) of comorbidities. Advancing age, post-menopauusal status and not being married were significant factors for presence of comorbidities. Median follow-up was 27 months (95% CI 26.25-28.55 months). Presence of multiple comorbidities was a poor prognostic factor for both PFS (2-yr PFS 85% vs 77%) and OS (2-yr OS 89% vs 79%) (both p=0.04) but no such correlation for CCI score.

Conclusion: Breast cancer treatment impacted incidence of comorbidities. Presence of multiple comorbidities had an adverse impact on survival. Hence, further research on treatment optimization is required in patients with substantial comorbidities.