[Variables associated with cognitive deterioration in Parkinson's disease]

The relation between Parkinson s disease (EP) and dementia is both complex and controversial in definition, epidemiology and pathology. Data on the prevalence of dementia in EP vary widely owing to the different populations studied and differences in the definitions used. However, the large population studies (> 200,000 persons), with details of the clinical features of the cases reviewed, show a prevalence of nearly 30%.

We wished to investigate whether certain clinical variables in patients with Parkinson s disease, with or without cognitive deterioration might affect the development of neurodegenerative conditions in these patients.

The 23 patients with Parkinson s disease included in this study were selected on the clinico-diagnostic criteria of idiopathic Parkinson s disease, namely on the following clinical characteristics: resting tremor, bradykinesia, rigidity and postural instability; we considered that the patients had cognitive deterioration when they obtained scores below 28 points on the cognitive mini-examination, a Spanish adaptation of the Mini Mental State Examination, which has a maximum possible score of 35 points.

The results show significant differences in some of the variables studied.

We wished to show which variables, such as the age of onset of symptoms and degree of severity of the extrapyramidal disorder in patients with EP, are risk factors for development of neurodegenerative conditions in these patients.