Complications of Parkinson’s disease (PD) fall under two main categories: non-motor symptoms that include cognitive deterioration, neuropsychiatric problems, autonomic dysfunction, fatigue, pain and sleep disturbances; and the classical motor symptoms that include tremor, rigidity, bradykinesia and postural instability. Advanced PD is associated with a progressive increase in the severity of these symptoms.

Complications may also arise from ongoing therapeutic treatments that can result in the exacerbation of both motor and non-motor symptoms, or the appearance of adverse side effects. Current management of PD is focused on alleviating symptoms rather than preventing their appearance largely due to the idiopathic nature of PD in the vast majority of patients.

Clearly, complications arising from symptoms of the disease, or due to therapy-induced side affects, can severely impact on the quality of life of patients, and the loss of function experienced by younger patients with advanced PD can be particularly distressing. Moreover, the worsening of complications in advanced PD will increasingly have debilitating effects on patients for which they, their families and health care professionals are not necessarily prepared.