Association of polypharmacy with colorectal cancer survival among older patients
Menée en Allemagne à partir de données portant sur 3 239 patients atteints d'un cancer colorectal et âgés de plus de 65 ans, cette étude analyse l'association entre une polypharmacie et la survie (durée de suivi : 5 ans ; 1 070 décès dont 615 par cancer)
Background : In geriatric oncology, polypharmacy is often assessed during a comprehensive geriatric assessment. Previous studies about its association with survival among colorectal cancer (CRC) patients were inconclusive and had high risk for indication bias. Patients and Methods : A cohort study was conducted with 3,239 CRC patients, aged ≥65 years, who were recruited in Germany between 2003 and 2016 while being hospitalized for CRC surgery. We defined polypharmacy as concurrent use of 5 or more drugs, and excessive polypharmacy (EPP) as concurrent use of 8 or more drugs. Cox proportional hazards regression models were performed to assess the associations of polypharmacy with 5-year overall (OS), CRC specific (CSS), and non-cancer specific survival (NCS) with rigorous adjustment for morbidity to minimize indication bias (e.g., for cancer stage, functional status, and 13 common diseases/conditions). Results : The prevalence of polypharmacy was 54.7% and that of EPP was 24.2%. During up to 5 years of follow-up, 1,070 participants died among whom 615 died of CRC and 296 died of other causes than cancer. EPP was statistically significantly associated with poorer up to 5-year OS (hazard ratio (HR) [95% CI]: 1.23 [1.02–1.47]) and CSS (1.31 [1.03-1.68]). HR point estimate for NCS was higher than 1 (1.22) but not statistically significant. Conclusion : Polypharmacy was very common and EPP was a weak risk factor for mortality in this large cohort of older CRC patients. Clinical trials are needed to address the causality of this relationship because older CRC patients might benefit from de-prescribing drugs without an indication. Implications for Practice : The results of our study support the hypothesis that excessive polypharmacy, defined as use of 8 or more concurrently used active substances, has a negative impact on older colorectal cancer (CRC) patients’ prognosis. Our study suggests to oncologists that performing a medication review for older CRC patients with 8 drugs or more is indicated (especially when a broader comprehensive geriatric assessment is being performed). Such a medication review should not only focus on reducing the number of medications (by de-prescribing drugs without an indication) but should also check the appropriateness of indicated drugs for older (cancer) patients.