The prevalence and aetiology of long-term L-dopa side-effects in elderly parkinsonian patients.

Fifty-one elderly parkinsonian patients (mean age 80 years) on long-term (greater than 5 years) L-dopa therapy were identified from the patients within the three geriatric units in Edinburgh. Side-effects were identified in 57% of patients and tended to be mild in severity. Mean duration of disease was 10.2 years in those with side-effects and 6.7 years in those without (p less than 0.01). Past and present L-dopa side-effects are more likely to be caused by disease progression than by L-dopa therapy. It is therefore recommended that L-dopa should be prescribed at disease onset to elderly Parkinsonian patients.