(B-003) DARWIN EU® - Prevalence of Frailty and Polypharmacy in Selected Cancers: results from Six European Countries in a Real-World Context

Background: Assessing frailty and polypharmacy is challenging due to the lack of standardised definitions, yet their impact on cancer treatment and outcomes is significant. Studies examining their prevalence in cancer using real-world evidence are limited.

Objectives: To estimate the prevalence of frailty and polypharmacy at cancer diagnosis in selected cancers using an electronic frailty score (EFS) and to estimate one-year hospitalisation and mortality by frailty and polypharmacy.

Methods: Population-level cohort study using primary care (Germany, Belgium, UK, Spain, and Netherlands) and population-based biobank-linked data (Estonia), mapped to OMOP CDM. Individuals aged ≥18 years, ≥ 365 days of prior database history, with an incident cancer diagnosis (index date) of selected cancers (Lung, Breast, Ovary, Endometrium, Prostate, Pancreas, Colorectal cancer, Lymphoma, Leukemia, or Multiple myeloma) between 2017-2022 were included. Polypharmacy was defined as the maximum number of overlapping prescriptions (≥5) 90 days before index. The EFS included 36 items (suggested by prior research using electronic healthcare data to identify cumulative deficits): polypharmacy, conditions, symptoms/signs, and disabilities. Frailty severity categories were calculated (number of conditions/36): fit: 0–0.12; mild: >0.12–0.24; moderate≥0.24–0.36; and severe: ≥0.36. Frailty was defined as EFS >0.12. Proportions were reported for each frailty category and polypharmacy. Hospitalisation (rate) and mortality (risk) (number of events within the year from index/the total number of individuals within that category) were expressed as rate and percentage, respectively.

Results: Individuals with incident cancers totaled 350,203 (66.2% were ≥ 65 years). The median EFS at cancer diagnosis ranged between 0.056 (Netherlands and Germany) and 0.139 (Estonia). By frailty categories, most individuals were fit, ranging from 41.7-76.3%. Frailty (EFS>0.12) ranged between 23.7-58.3% (Germany and Estonia, respectively). Across all databases, the proportion of individuals decreased with increasing frailty severity. The prevalence of severe frailty was low, ranging between 0.2- 5%. Polypharmacy ranged between 19-56.2% (Germany and Spain, respectively). Hospitalisation rates ranged from fit to severely frail, between 1.2-1.5 (Spain) and 3.3-3.7 (Estonia). All databases had a positive gradient between frailty and mortality risk, ranging between 13-25% among fit and 35-72% in severely frail.

Conclusions: Frailty and polypharmacy were highly prevalent at cancer diagnosis, with a positive gradient between EFS and hospitalisation and mortality. Results align with prior research on which the EFS was based, supporting its applicability in this population.