Parkinson's disease often misdiagnosed
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RHYL, UNITED KINGDOM. British doctors at the Glan Clwyd Hospital have just issued a report which concludes that Parkinson's disease is often misdiagnosed. Their study involved 402 patients who had been diagnosed with Parkinson's disease in 74 general medical practices across Wales. The patients were examined by specialists who concluded that only about half of them (213) actually had true Parkinson's disease. Although most of the patients (74 per cent) had some form of parkinsonism, no parkinsonism was detected in 103 (26 per cent) of the patients. Half of these patients actually suffered from essential tremor (which requires quite different medication) while 16 per cent actually had Alzheimer's rather than Parkinson's disease.

Nevertheless, all 402 patients had been prescribed medications for Parkinson's disease (mainly levodopa). The doctors point out that only about half of these patients would have derived any benefit from their medication (as only half of them actually had Parkinson's disease); the other half would merely have been stuck with the side effects of the medications which can be quite severe. The doctors strongly urge general practitioners to refer patients with suspected Parkinson's disease to specialists before initiating drug therapy.
Meara, Jolyon, et al. Accuracy of diagnosis in patients with presumed Parkinson's disease. Age and Ageing, Vol. 28, March 1999, pp. 99-102