Parkinson's disease, parkinsonism and aging

Parkinson's disease (PD) is a neurological disorder of unknown cause. PD is characterized by the progressive death of dopaminergic neurons of the pars compacta of the substantia nigra and by the presence of Lewy's bodies. The neuronal loss is estimated to be 60 to 70 % at the onset of symptoms. When the striatal dopamine has been depleted to 20 % of normal, the PD will occur, The elderly are more likely to be near to the critical 20 % level and so they are at risk of PD and parkinsonism. The clinical diagnosis of PD is based on the identification of the cardinal motor signs of bradykinesia, rigidity, tremor and postural instability. The syndrome of parkinsonism may have different causes and it is necessary to distinguish parkinsonism due to other common causes from PD. Vascular parkinsonism and drug-induced parkinsonism are frequent in elderly patients. Age is the single, most consistent risk factor, and therefore, the prevalence of PD and parkinsonism will rise steadily in the future. The results of the Italian Longitudinal Study on Aging (ILSA) working group showed that in elderly Italian population the incidence of PD and parkinsonism increased with age, PD was the most common type of parkinsonism, and men had a risk of developing PD twice as much as women. Cardiovascular and gastrointestinal autonomic dysfunctions, dementia, depression, hallucinations and sensory symptoms are common nonmotorial clinical features of PD and compromise the functional status and the quality of life of elderly patients.