Frailty for neurologists: perspectives on how frailty influences care planning.

The concept of frailty, now being adopted in most medical disciplines, is attracting growing interest in neurology. Every day, most neurologists care for patients with varying degrees of frailty, from very mild to very severe. Frailty exacerbates patients' health needs, complicates clinical decision making, and negatively affects their health outcomes. Increasing evidence suggests that frailty affects the risk, clinical presentation, and course of common age-related neurological disorders, including dementia, Parkinson's disease, stroke, and multiple sclerosis. Most neurologists should become familiar with assessing and measuring frailty. Doing so can provide information that is crucial for diagnosis, prognostication, and care planning. Consideration of frailty can help to elucidate the pathophysiological underpinnings of age-related neurological disorders, clarify the clinical validity and utility of candidate biomarkers, and identify novel therapeutic targets. Randomised controlled trials investigating late-life neurological diseases that address frailty have the potential to provide insight into these complex disorders.