Serum creatine kinase is elevated in patients with Parkinson's disease: a case controlled study

We report serum creatine kinase (CK) activity level in patients with Parkinson's disease and controls matched with gender and age. The clinical subjects consist of 84 patients with Parkinson's disease and 257 control subjects. Serum CK level was significantly elevated in parkinsonian patients (117.3+/-65.0 units/l) compared to that of the controls (85.1+/-33.2 units/l) (p<0.01). The elevation correlated with the use of levodopa and the duration of the disease. In our study, 56.0% of parkinsonian patients and 32.7 % of the control subjects showed higher than normal upper limits of serum CK activity (p<0.01). Whereas no correlation was noted between serum CK level and Hoehn-Yahr stage, age of onset, duration of the disease, predominant symptoms (rigidity vs. tremor), and average daily dose of levodopa. Patients with Parkinson's disease may be sensitive to physical activity resulting in leakage of CK from skeletal muscles. Neural mechanism mediated by hypothalamic dopamine and by autonomic nervous system may also be contributing to the elevation of serum CK.