Primitive reflex evaluation in the clinical assessment of extrapyramidal syndromes.

The aim of the present study was to evaluate the role of primitive reflexes (PRs) as additional alert sign in routine clinical practice in patients with extrapyramidal syndrome. We considered glabellar, snout, palmomental and grasp reflexes in patients with mild stage of Lewy body dementia (LBD), corticobasal degeneration, progressive supranuclear palsy or Parkinson disease (PD). We also enrolled mild Alzheimer disease (AD) patients, and healthy subjects, as controls. LBD patients showed the highest prevalence of PRs compared with the other groups. The odds ratio of the risk of LBD in PRs > or = 2 was 27.9 (95% CI 2.9-269.0) compared with control group, 14.6 (95% CI 2.7-79.6) compared with mild AD, and 19.7 (95% CI 3.7-104.3) compared with PD. These data suggest that the occurrence of combination of PRs might be an useful additional warning sign of possible diffuse Lewy body pathology more than other causes of extrapyramidal syndrome.