Status of the disease is the one of main concerns of clinicians, especially in the course of primary degenerative disorders. In Parkinson’s disease (PD), Unified Parkinson’s Disease Rating Scale (UPDRS) is an useful clinical score that can express severity of parkinsonian symptoms, but L-DOPA treatment and motor fluctuations can change the UPDRS scores. Even in the best ‘on’ state, there can be residual motor deficits, and it is very difficult to estimate the worst ‘off’ state due to long duration effect of L-DOPA.

To find relevant examination scores of ‘on’ or ‘off’ state of PD patients which correlates with clinical and demographic variables those can represents the status of Parkinson’s disease.

Sixty-four patients with PD (24 male, age 63.0±8.6 years, Hoehn and Yahr stage (HY) 2.8±0.5) were examined UPDRS at ‘on’ and practically defined ‘off’ (12 hours after last medication) state. We evaluated the association between the ‘on’ and ‘off’ scores of UPDRS and duration of disease and treatment, and equivalent L-DOPA dose of the patients. Patients were grouped according to the presence of motor fluctuation to find the differences in those associations.

There were significantly strong correlations between UPDRS ‘off’ scores and clinical variables such as duration of disease and treatment. In ‘on’ state, only complication part of UPDRS was correlated with duration of disease and treatment, but activity of daily living (ADL) and motor part of UPDRS were correlated well with age of the patients. Age at disease onset showed significant negative association with the difference between ‘off’ and ‘on’ state UPDRS scores. Thirty-one patients who had motor fluctuation (9 male, age 62.7±9.3 years, HY 3.0±0.6) showed significantly increased duration of the disease, duration of L-DOPA treatment and equivalent DOPA dose compared to those of 33 patients without motor fluctuation (15 male, age 63.3±8.1 years, HY 2.6±0.3). In patients without motor fluctuation, both ‘off’ and ‘on’ UPDRS showed association with duration of disease and treatment, but ‘off’ and ‘off’ – ‘on’ difference of UPDRS were better correlated with duration of disease and treatment in patients with motor fluctuation.

We found that the UPDRS scores of practically defined ‘off’ state significantly correlated with the duration of the disease and treatment. Patients with motor fluctuation revealed better responsiveness to medication than those without motor fluctuation. In patients without motor fluctuation, UPDRS scores of ‘on’ state can reflect the clinical presentation as much as those of ‘off’ state.