Multimorbidity and Frailty: Tackling Complexity in Parkinson's Disease.

Parkinson's disease (PD) is a condition that predominantly affects older people. It is imperative that clinical management considers the other significant illnesses that people with PD accumulate as they age in conjunction with their resilience to cope with physiological change. Multimorbidity and frailty act synergistically to heighten the risk of adverse outcomes for older people with PD. These states are associated with increased likelihood of hospitalization, polypharmacy, adverse drug effects including the anticholinergic burden of medications, drug-disease and drug-drug interactions. Management should be integrated, holistic and individualised to meticulously balance the risks of interventions considering the vulnerability of the individual to recover from disturbance to their environmental, physical and cognitive equilibrium.