Pharmacology of aging and cancer

Abstract

Advanced age is the number one risk factor for the development of cancer. As a result, older adults (≥65 years old) represent the majority of patients with cancer globally. By 2030, around 70% of all cancer diagnoses will be made in adults 65 years and older. Older patients are often less fit and, in general, tolerate medical therapies poorly. Advanced age is accompanied by many physiologic changes which can impact the pharmacology, pharmacokinetics, and pharmacodynamics of medications. Moreover, older patients tend to accumulate medications over time, leading to polypharmacy (PP). Polypharmacy is a “disease” that has many risk factors and causes which can potentially lead to poor outcomes. Deprescribing, or the process of systematically reducing or discontinuing drugs, has been deemed an effective “cure” for PP. Older patients with cancer are particularly susceptible to adverse outcomes from PP and potentially inappropriate medications (PIMs). This chapter describes the impact of aging and cancer on geriatric pharmacotherapy as well as the incidence and definitions of PP and PIMs in the context of geriatric oncology. Finally, processes and models of deprescribing that can be applied to older patients with cancer are discussed.