[Restless-legs syndrome]

The Association Between Vitamin D Level and Restless Legs Syndrome: A Population-Based Case-Control Study

STUDY OBJECTIVES

The pathophysiology of restless legs syndrome (RLS) may be related to abnormalities in central dopamine pathways. Vitamin D may play a role in the pathophysiology of RLS by modulating the dopaminergic system. The aim of our study is to examine the possible link between RLS and vitamin D deficiency.

METHODS

The total number of subjects enrolled was 201, including 78 patients with RLS based on the International RLS Study Group (IRLSSG) diagnostic criteria and 123 controls. Serum 25-hydroxy vitamin D levels were measured in both groups. RLS severity was assessed in all cases using the IRLSSG symptom severity rating scale.

RESULTS

Fifty-nine patients with RLS (75.6%) and 52 controls (42.3%) had a diagnosis of vitamin D deficiency, P < .001. The odds ratio (OR) of the development of RLS was 4.24 for those with a vitamin D level < 50 nmol/L compared to those with a vitamin D level ≥ 50 nmol/L (P < .001, 95% confidence interval [CI] 2.3-7.9). After adjusting for all other significant factors in the multivariate logistic model, vitamin D was significantly associated with RLS (OR 3.1, P < .002, 95% CI 1.51-6.38). Moreover, a dark or black skin color (OR 3.4, P < .001, 95% CI 1.5-6.3) and working as a teacher (OR 8.8, P < .001, 95% CI 3.4-23.5) were also independently significantly associated with RLS.

CONCLUSIONS

Our study identified an association between vitamin D deficiency and RLS. Consequently, vitamin D deficiency should be considered in the management of RLS. However, further studies are needed to evaluate the causality relationship between vitamin D level and RLS.

Association between restless legs syndrome and CLOCK and NPAS2 gene polymorphisms in schizophrenia

Previous studies have suggested that there is a genetic basis to restless legs syndrome (RLS) development. Occurrence of antipsychotic-induced RLS could also be due to differences in genetic susceptibility. We investigated whether CLOCK and NPAS2 gene polymorphisms are associated with RLS in schizophrenic patients on antipsychotics because RLS symptoms usually manifest during the evening and night. We assessed symptoms of RLS in 190 Korean schizophrenic patients on antipsychotics and divided the subjects into two groups according to the International Restless Legs Syndrome Study Group diagnostic criteria: (i) subjects who met all the criteria and (ii) the remaining subjects who did not meet all the criteria. We found a significant difference in the number of subjects with different genotype and allele carrier frequencies for the CLOCK gene (rs2412646) between the two groups (p = 0.031 and 0.010, respectively). Distribution of CLOCK haplotypes (rs2412646-rs1801260) was significantly different between schizophrenic patients with and without RLS (p = 0.021). However, the distributions of allelic, genotypic, and haplotypic variants of NPAS2 (rs2305160 and rs6725296) were not significantly different between the two groups. Our results suggest that CLOCK polymorphisms are associated with increased susceptibility of schizophrenic patients to RLS. We hypothesize that RLS in schizophrenia patients treated with antipsychotics may be a very mild akathisia that manifests during the night and is under control of circadian oscillation.

Restless leg syndrome in diabetics compared with normal controls

Introduction. Restless leg syndrome (RLS) is a common sleep disorder which is characterized by urge to move the legs accompanied by disturbing and uncomfortable leg sensation during night and rest. This common condition affects 7–10% of general population and is frequently unrecognized, misdiagnosed, and poorly managed. Several clinical conditions like diabetes have been associated with secondary form of RLS. This study analyzed the frequency and possible risk factor for RLS development in diabetic patient. Material and Methods. This descriptive case-control study was done on 140 consecutive outpatient diabetics and age, sex, and body mass index matched control group. RLS was diagnosed by criteria of the International RLS Study Group. Results. Prevalence of RLS was 28.6% in diabetes and 7.1% in control group (P = 0.001). Sex difference was not significant and with rising duration of diabetes prevalence of RLS was not increased. Discussion. With regarding significant association between RLS and diabetes and its negative impact on quality of life/health outcome/sleep/daytime activity/cognitive function/ and mental state of diabetic patient/higher awareness of RLS among physicians and related health worker suggested.

Restless legs syndrome associated with exercise intolerance: Data from a retrospective observational clinical neuromuscular center study

INTRODUCTION

Exercise intolerance (EI) is a frequent motive for seeking neuromuscular consultation and may be a sign of metabolic disease or, rarely, muscular dystrophy. The diagnosis is not established in many patients with a typical clinical presentation. Nevertheless, some of them complain of sleep disorders and more especially of restless legs syndrome (RLS).

OBJECTIVE

The objective of our study was to estimate the frequency of RLS in patients presenting with EI.

METHODS

Our retrospective observational study included all patients seen in the center from 2005 to 2011, who were subsequently investigated for EI in the neuromuscular department of the Caen University hospital. Data were collected on clinical RLS and muscular investigations (creatine kinase [CK], EMG, maximal exercise tests magnetic resonance imaging [MRI] and muscle biopsy obtained along with muscle exploration).

RESULTS

Of the 318 patient records analyzed, 84 showed patients accurately complaining of EI. RLS was diagnosed in 25 of these patients (29.7%). This percentage was significantly higher (P<0.001) than found in the general population. Improvement was seen in 91.3% of the patients receiving specific treatment.

CONCLUSION

RLS can sometimes present with pain, potentially worsening with exercise, inappropriately leading to a hypothesis of EI. Clinicians should thus explore the possible diagnosis of RLS when a muscular disease is not found in patients presenting with such symptoms.

[Fatigue and sleep disorders of patients with colorectal cancer]

Fatigue and sleep disorders impact the quality of life of cancer patients. They do not put the vital prognosis at stake, but are debilitating and as a whole poorly treated. This article is oriented toward the fatigue and sleep disorders of patients with colorectal cancer. Special emphasis is put on the necessary clinical work up, on various available scales, indexes, inventories, questionnaires and on actigraphy and polysomnography, on the semiology of these disorders, on their mechanisms and on the recent therapeutic methods which are still insufficiently distributed.

[Acute exacerbation of restless legs syndrome during perioperative procedures: case reports and suggested management]

Restless legs syndrome, or Ekbom syndrome, is a common (yet poorly recognized) neurological condition, with sensitive and motor symptoms and a probable genetic vulnerability. The subjects experience an imperious urge to move their legs at rest, possibly associated with paresthesia and pain, which occurs mostly in the evening and night, and is transiently relieved by movements and walking. Severe cases suffer from involuntary leg jerks during quiet wake and severe insomnia. The syndrome is more frequent in middle-aged subjects, in women, and in iron deficient subjects (renal insufficiency, pregnancy, multiparous mothers). We report a series of patients with a severe restless legs syndrome, adequately treated with small doses of dopamine agonist in the evening. They experienced a perioperative, acute exacerbation of their syndrome. The inability to stay still with involuntary jerks in the operating room, the generalized pain followed by suicidal thoughts, and the agitation with akathisia in the recovery room, complicated the surgery procedures and their follow-ups. The prevention of restless legs exacerbation includes: (i) contra-indicating hydroxyzine, droperidol and any other drug blocking the central dopamine transmission before and during anaesthesia; (ii) using intravenous or subcutaneous opioids, and benzodiazepines during and after the surgery procedure; (iii) temporary increasing the dosage of dopamine agents after surgery; (iv) monitoring (and compensating if low) the iron stores after surgery.

Psychopharmacology of ADHD in pediatrics: current advances and issues

Attention deficit hyperactivity disorder (ADHD) is a neurobehavioral developmental disorder found in 3% to 8% of children and adolescents. An important part of ADHD management is psychopharmacology, which includes stimulants, norepinephrine reuptake inhibitors, alpha-2 agonists, and antidepressants. Medications with the best evidence-based support for ADHD management are the stimulants methylphenidate and amphetamine. A number of newer, long-acting stimulants are now available and a number of new medications are considered that are under current research.