INTRODUCTION
Frailty is most often defined as an aging-related syndrome of physiological decline, characterized by marked vulnerability to adverse health outcomes. Frail older patients often present with an increased burden of symptoms including weakness and fatigue, medical complexity, and reduced tolerance to medical and surgical interventions. Awareness of frailty and associated risks for adverse health outcomes can improve care for this most vulnerable subset of patients.Although there is no gold standard for detecting frailty, multiple frailty screening tools have been developed and utilized for risk assessment and epidemiologic study.
This topic will review the definitions, pathophysiology, prevalence, and diagnosis of frailty and clinical approaches that may attenuate vulnerability and relieve symptoms.
PREVALENCE
Many population-based studies of frailty have been performed using a variety of frailty measures. Although the prevalence of frailty varies with the tool used and with the population studied, prevalence in several studies in the United States ranges from 4 to 16 percent in community-dwelling men and women aged 65 and older [1-5] and up to 43 percent of older patients with cancer [6]. Pre-frailty (patients at risk for frailty who fulfill some, not but all, criteria for frailty) has a prevalence ranging from 28 to 44 percent in those over 65 years old [1,4,5].A 2012 systematic review found that when frailty was defined on the basis of physical findings alone, overall prevalence in 15 studies (44,894 participants) was 9.9 percent; when psychosocial aspects were included in the definition, prevalence was 13.6 percent among eight studies (24,072 participants) [7]. In a European study (the Survey of Health, Ageing, and Retirement in Europe [SHARE]) comparing eight frailty scales, frailty prevalence ranged from 6 to 44 percent when applied to a database of individuals aged 50 to 104 years [8]. In a US study of people aged 90 and older, the prevalence of frailty was 24 percent for those aged 90 to 94 and 39.5 percent for those 95 and older [9].