Utility of the sickness impact profile in Parkinson's disease.

The Sickness Impact Profile (SIP) is a questionnaire consisting of 136 items grouped into 12 categories and two dimensions (physical and psychosocial). To characterize its utility in Parkinson's disease (PD), we administered the SIP to 44 consecutive clinic patients with PD. Compared to 44 age- and sex-matched control subjects, PD patients had their greatest dysfunction in the categories of mobility, communication, and home management. The two items that PD patients most commonly endorsed were, "I am having trouble writing or typing" (75%) and, "My sexual activity is decreased" (61%). In general, these treated PD patients had greater dysfunction in the psychosocial than physical dimensions. Two simple PD-specific scales correlated well with the physical dimension score but less so with the psychosocial dimension, suggesting that the SIP assesses more functional domains than the PD-specific scales used. The SIP holds some promise as a broad measure of functional status in PD patients.