OBJECTIVE: Parkinson's Disease (PD) is a neurodegenerative condition, with increasing resource use consequences as patients progress. The purpose of this study was to investigate differences in resource use for patients in different stages of PD. METHODS: Data are drawn from a large cross-sectional observational study of patients receiving treatment for PD. A panel of neurologists were asked to include the next ten patients consulting with PD during a specified time period. Information collected includes behavioural and attitudinal patient management and resource use data. RESULTS: The study included 4234 patients treated by 428 doctors in the US and five European countries. Disease state was measured by Hoehn and Yahr (HY) scale, ranging from one (mild unilateral tremor, some rigidity, minimal bradykinesia) to four (severe disability) and five (complete immobility). Patients with HY score four and five were grouped due to small numbers with HY five. There were no significant differences in HY distribution between the EU and US. Likelihood of hospitalisation and admission for respite care is much greater in Europe than the US (24.0% vs. 6.7%; p<0.01 and 4.7% vs. 0.6%; p<0.01). Hospital stay was also greater in EU (16.3 vs. 6.7 days; p<0.01). Likelihood of both hospitalisation and respite care correlated with worsening HY score. Drug use patterns were similar in EU and US. Patients with HY score of four and five took more drugs than patients with HY one (mean number 2.15 vs. 1.15; p<0.01). Likelihood of combination therapy (particularly with levodopa) increased with worsening HY score; at HY 4/5 levodopa therapy is much more common than at HY1 (86% vs. 35%; p<0.01). CONCLUSION: Resource use and cost increase as the severity of PD worsens. The most significant resource use increases occur when patients reach HY4 due to mounting disability resulting in increased hospitalisation and combination drug therapy.