Charlson Comorbidities Associated With Lower Likelihood of CR in Epithelial Ovarian Cancer

Kimberly Cannavale, MPH

The presence of comorbidities prior to ovarian cancer diagnosis may contribute to inferior treatment outcomes in patients with epithelial ovarian cancer, according to Kimberly Cannavale, MPH.

A crude analysis of a retrospective cohort study found that among 799 patients with ovarian cancer, those with Charlson comorbidity index scores of 1 and 2 or higher had a lower likelihood of achieving complete remission (CR) with ovarian cancer therapy compared with those with a Charlson comorbidity index score of 0 (RR = 0.84 [95% CI, 0.76-0.93] and RR = 0.72 [95% CI, 0.64-0.81], respectively).¹

The multivariable analysis demonstrated similar likelihoods of achieving CR between patients with no Charlson comorbidities and those with a Charlson comorbidity index of 1 (RR = 0.84; 95% CI, 0.77-0.92) and 2 or higher (RR = 0.81; 95% CI, 0.72-0.91). Furthermore, attenuated associations between comorbidities and clinical remission were observed between patients with no Charlson comorbidities and those with a Charlson comorbidity index score of 1 (RR = 0.95; 95% CI, 0.89-1.01) and 2 or higher (R = 0.92; 95% CI, 0.86- 1.00).

“These findings contribute to the knowledge base that comorbidities may have a role, or at least a partial role, in adversely affecting the likelihood of achieving CR for patients with ovarian cancer,” Cannavale said in an interview with OncLive®.

In the interview, Cannavale, a project manager in the Research and Evaluation Department of Kaiser Permanente in Pasadena, California, discussed previously unanswered questions that inspired this study, highlighted key findings from the research, and shared how this information may impact future treatment considerations for patients with ovarian cancer.

OncLive: What was the rationale for this study?

Cannavale: Our research focused on how ovarian cancer management and short-term outcomes have been altered due to the COVID-19 pandemic. The original analysis examined the association between the pandemic period and remission outcomes, with the model adjusting for comorbidity as a potential confounder. In this analysis, we observed that having any Charlson comorbidity was associated with a lower likelihood of CR. This finding has clinical implications.

This ancillary finding that having any Charlson comorbidity is associated with a lower likelihood of CR is highly relevant to ovarian cancer care. Prior studies have examined the role of comorbidity on overall survival [OS] in patients with ovarian cancer and have reported an association between comorbidity and inferior OS. However, it was unclear whether the inferior OS was due to excess mortality from the comorbidities themselves, their impact on ovarian cancer treatment outcomes, or both.

What were the methods and design of this study?

This was a retrospective cohort study. We identified patients with ovarian cancer from the Kaiser Permanente Southern California [KPSC] Cancer Registry or via chart review for those who had an ICD-10 diagnosis code. Each patient’s Charlson comorbidity index was determined based on data [collected during] a 12-month window prior to their ovarian cancer diagnosis.

Patients’ remission outcomes were ascertained via chart review, where we considered physicians’ assessments, CA-125 lab values, and imaging evidence that they were in remission. Data on potential confounders, which included the pandemic period, age, race, ethnicity, International Federation of Gynecology and Obstetrics stage, prior length of membership, and time to treatment, were all obtained from KPSC electronic medical records.

Bivariate and multivariable modified Poisson regressions adjusting for the potential confounders were used to evaluate the association between Charlson comorbidity index and achieving CR or clinical remission by the end of treatment. We evaluated patients diagnosed with ovarian cancer epithelial subtypes between January 1, 2017, and June 30, 2021, at KPSC, which is a large, integrated health care delivery system.

Please expand on the key findings from this study.

In the crude analysis, patients who had 1 or 2 or more comorbid conditions under the Charlson comorbidity index had a lower likelihood of achieving CR compared with those who had no comorbid conditions. Additionally, in the multivariable analysis, patients who had 1 or 2 or more comorbid conditions were also found to have a lower likelihood of achieving CR compared with those with no comorbid conditions. Similar findings were observed for clinical remission, although the associations were attenuated.

What are the potential next steps for this research?

Future studies could investigate the potential mechanism underlying this association to inform patient treatment. For example, comorbidities may affect the receipt of guideline-concordant treatment. We have no plans at this time to evaluate this, but it’s certainly [a direction] our team could consider studying in the future.

Reference

Cannavale KL, Mukherjee A, Xu L, et al. Charlson’s comorbidity and remission outcomes in women diagnosed with epithelial ovarian cancer. J Clin Oncol. 2024;42(suppl 16):e17562. doi:10.1200/JCO.2024.42.16_suppl.e17562