High Prevalence of Undiagnosed Insulin Resistance in Non-Diabetic Subjects with Parkinson's Disease.

Background: Reduced glucose tolerance has been long recognized as a potential risk factor for Parkinson's disease (PD), and increasing scrutiny is currently being placed on insulin resistance (IR) as a pathologic driver of neurodegeneration. However, the prevalence of IR in PD is unknown.

Objective: To determine IR prevalence in non-diabetic patients with PD and to correlate IR with other metabolic indicators, motor and non-motor symptoms (NMS) of PD, and quality of life (QoL).

Constipation is reduced by beta-blockers and increased by dopaminergic medications in Parkinson's disease.

Background: Constipation is one of most frequent non-motor symptoms of Parkinson's disease (PD) and it may precede the clinical diagnosis of PD by years, with negative effects on quality of life. In contrast to motor features, levodopa is ineffective and possibly detrimental on constipation. Treatment of constipation in PD is non-specific and frequently unsuccessful.