Role of the Oral Glucose Tolerance Test (OGTT) in the idiopathic restless legs syndrome
Received 10 April 2009; received in revised form 4 September 2009; accepted 8 September 2009. published online 28 September 2009.
Abstract
Background
Restless legs syndrome (RLS) is a sensorimotor disorder characterised by a distressing urge to move the legs. Several clinical conditions have been associated with RLS, such as iron deficiency, uraemia, pregnancy, polyneuropathy and Diabetes Mellitus (DM). However the causes remain unknown in about 70–80% of cases.
Objective
To evaluate the role of glucose metabolism abnormalities in idiopathic RLS.
Methods
We enrolled 132 consecutive patients with idiopathic RLS associated with normal fasting glycaemia and 128 control subjects. We evaluated glucose and insulin levels after a 2-h oral glucose tolerance test (2h-OGTT) in patients and control subjects. In addition we determined Insulin Resistance (IR) by Homa-Index.
Results
After 2h-OGTT, the prevalence of glucose metabolism abnormalities was significantly higher in patients with RLS than in controls (P=.002). Impaired Glucose Tolerance (IGT) was found in 54 (41%) patients and in 23 (18%) controls, while a new-diagnosed DM (NDDM) was found in 25 (19%) patients and in 8 (6%) controls. The IR showed no significant differences between patients and controls.
Conclusions
Our study suggests that IGT (prediabetes) is frequently associated with idiopathic RLS. We propose to perform a 2h-OGTT in idiopathic RLS patients with normal fasting glycaemia.
aDepartment of Neuroscience, “S. Giovanni di Dio” Hospital, 88900, Crotone, Italy
bPharmacology, Course of Clinical Pharmacy, loc. Roccelletta, University “Magna Graecia”, 88100 Catanzaro, Italy
cDepartment of Neuroscience, “S. Giovanni Paolo II” Hospital, 88046, Lamezia Terme, Italy
dDepartment of Neuroscience, “G. Jazzolino” Hospital, 89900, Vibo Valentia, Italy
eServ. of Anatomo-Pathology, “S. Giovanni di Dio” Hospital, 88900, Crotone, Italy
fNeurology, Department of Medical Science, Campus Universitario, loc. Germaneto, University “Magna Graecia”, 88100, Catanzaro, Italy
gEndocrinology, Department of Clinical and Experimental Medicine, Campus Universitario, loc. Germaneto, University “Magna Graecia”, 88100, Catanzaro, Italy
Corresponding author. Department of Neuroscience, “S. Giovanni di Dio” Hospital, Via Largo Bologna, 88900, Crotone, Italy. Tel.: +39 0962 92 42 41; fax: +39 0962 92 45 61.
ABSTRACT