Polypharmacy among Older Advanced Lung Cancer Patients taking EGFR
Tyrosine Kinase Inhibitors
Abstract
Aim: Polypharmacy (PP) is a common problem among the older adults and
has a potential effect on health-related problems. However, the
significance of PP in older advanced non–small cell lung cancer (NSCLC)
patients and those on oral molecular-targeted anticancer agents is
unclear. Methods: This retrospective study reviewed the records of 334
advanced NSCLC patients who underwent epidermal growth factor receptor
tyrosine kinase inhibitor (EGFR-TKI) treatment. PP was defined as
>=5 concomitant medications. Potentially inappropriate
medication (PIM) use was measured using the updated screening tool of
older people’s prescriptions (STOPP) ver. 2 criteria. We also estimated
survival distributions using the Kaplan–Meier method, compared
between–group differences using the log-rank test, explored potential
predictors of survival using Cox regression, and performed cluster
analysis to identify factors affecting multiple-medication use. Results:
The PP and PIM use prevalence was 38.4% and 31.9%, respectively. The
median overall survival (OS) for PP(+) and PP(–) patients was 19.4
months (95% CI = 14.1–24.8) and 27.3 months (95% CI = 22.6–36.4),
respectively (P < 0.001). Multivariate analysis revealed a
significant correlation between PP and OS. The frequency of unexpected
hospitalization during EGFR-TKI treatment was higher in PP(+) compared
to PP(–) patients (49.4% vs. 29.4%; P = 0.0032; OR = 2.34; 95% CI =
1.31–4.23). Conclusion: PP is an independent prognostic factor in older
NSCLC patients taking EGFR-TKIs. PP can be used as a simple indicator of
such patients’ comorbidities and symptoms or as a predictive marker of
unexpected hospitalization during treatment.