Accounting for frailty when treating chronic diseases.

Chronic diseases are considered to be major determinants of frailty and it could be hypothesized that their treatment may counteract the development of frailty. However, the hypothesis that intensive treatment of chronic diseases might reduce the progression of frailty is poorly supported by existing studies. In contrast, some evidence suggests that intensive treatment of chronic diseases may increase negative health outcomes in frail older adults. In particular, if treatment of symptoms related to chronic diseases (i.e. pain in osteoarthritis, dyspnoea in respiratory disease, motor symptoms in Parkinson disease) might potentially reverse frailty, the benefits related to preventive pharmacological treatment of chronic diseases (i.e. antihypertensive treatment) in patients with prevalent frailty is not certain. In particular, several factors might alter the risk/benefit ratio of a given treatment in persons with frailty. These include: exclusion of frail persons from clinical studies, reduced life expectancy in frail persons, increased susceptibility to iatrogenic events, and functional deficits associated with frailty. Therefore, frailty acts as an effect modifier, by modifying the risks and benefits of chronic disease treatments. This hypothesis must be considered and tested in future clinical intervention studies and clinical guidelines should provide specific recommendations for the treatment of frail people, underlining the pros and the cons of pharmacological treatment and possible targets for therapy in this population. Meanwhile, in older patients, the prescribing process should be individualized and flexible.