Family recurrence and oligo-anuria predict uremic restless legs syndrome

OBJECTIVES

To determine clinical and laboratory predictors of restless legs syndrome (RLS) in patients with end-stage kidney disease (ESKD) undergoing long-term hemodialysis (HD).

MATERIALS AND METHODS

One hundred and sixty-two consecutive patients were assessed. History of sleep disturbances, neurological examination, clinical, and laboratory data were collected. Patients with and without RLS were compared, and a logistic regression model described the relations between independent predictors and RLS.

RESULTS

Fifty-one patients (32%) currently had RLS (RLS+). RLS+ vs RLS- patients were more frequently women (49% vs 29%, P = 0.012), had first-degree relative with RLS (22% vs 6%, P = 0.004), insomnia (59% vs 36%, P = 0.007), peripheral neuropathy (41% vs 21%, P = 0.006), and low residual diuresis (92% vs 68% with below 500 ml/24 h, P = 0.001). Low (OR = 8.71, CI = 2.27-33.41; P = 0.002) and absent (OR = 4.96, CI = 1.52-16.20; P = 0.008) residual diuresis, peripheral neuropathy (OR = 4.00, CI = 1.44-11.14; P = 0.008), and first-degree relative with RLS (OR = 3.82, CI = 1.21-12.13; P = 0.023) significantly predicted RLS in ESKD patients undergoing HD.

CONCLUSION

Positive family history for RLS together with reduced/absent residual renal function and peripheral neuropathy predicts the risk for RLS in ESKD patients undergoing HD. Longitudinal studies are warranted to correlate RLS occurrence with genetic and environmental factors.

Absence of cardiovascular disease risk factors in restless legs syndrome

OBJECTIVE

Restless legs syndrome (RLS) might represent a condition at risk of cardiovascular (and cerebrovascular) disease; the role of sleep periodic leg movements, sleep deprivation, and presence of common risk factors for heart disease in these patients remains to be determined. The aim of this study was to evaluate the eventual presence of risk factors for cerebrovascular disease in RLS.

MATERIALS & METHODS

Eighty-seven consecutive patients affected by idiopathic RLS were included in this study together with 81 controls. Blood count, chemistry, and kidney function tests were obtained. We detected subjects suffering from diabetes mellitus, kidney diseases, heart diseases, disk herniation, neuropathy, blood diseases, liver diseases, artery diseases, dyslipidemia, or hypertension. Polysomnography was recorded in 66 patients, and cerebral neuroimaging was obtained in 59 patients with RLS.

RESULTS

None of the differences in blood test parameters was statistically significant; however, hypertension was found to be more frequent in controls and dyslipidemia was more frequent in patients with RLS, but this was explained by its higher frequency in patients also affected by obstructive sleep apnea. A diagnosis of cerebrovascular disease was posed for 14 patients with RLS (16.1%), but no predictive factor for its presence was found at the binomial logistic regression.

CONCLUSION

Our findings argue against the presence of an altered lipid metabolism as a risk factor for the development of cerebrovascular disease in patients with RLS, even if they do support the idea that cerebrovascular disease might be frequent in this condition.

[Sleep disorders in patients with chronic renal insufficiency]

Sleep disorders, especially insomnia, daytime sleepiness, sleep apnea syndrome and restless legs syndrome are very frequently encountered in patients with chronic renal failure whether or not they undergo renal replacement therapy. The causes of sleep disorders are multifactorial and not only linked to the renal disease itself, but also to its treatment and its associated psychosocial factors. This article discusses the prevalence and physiopathology of the most frequently encountered sleep disorders in chronic renal failure patients, and highlights the actually available therapeutic options.

The low prevalence of primary restless legs syndrome in Thai Parkinson's disease patients at Chulalongkorn University Hospital

OBJECTIVE

There have been many studies of the prevalence of restless legs syndrome (RLS) in Parkinson's disease (PD). Some studies found a lower prevalence than in comparable groups in the general population while others reported more RLS. The present study was designed to determine the prevalence of primary RLS in Thai PD patients.

MATERIAL AND METHOD

PD patients were interviewed for RLS symptoms and were excluded if they had a malignancy, endstage renal disease, neuropathy, a history of spinal cord diseases or were pregnant. Serum ferritin levels were measured.

RESULTS

Three out of 183 patients interviewed (1.6%) had symptoms consistent with RLS. When one patient who had a serum ferritin level of 31.9 ng/ml is excluded, the prevalence falls to 0.98%. None of the following variables were significantly different in patients with and without RLS: age, gender age at onset of PD, duration of PD, Hoehn and Yahr stage, serum ferritin level and dose and duration of dopaminergic medication. None of the patients who have had subthalamic nucleus deep brain stimulation (n = 5) had RLS.

CONCLUSION

The prevalence of RLS in Thai PD patients was found to be much lower than in most of the previous studies, especially those conducted in Europe and America.

Sleepiness in patients with obstructive sleep apnoea - daytime course and impact of nocturnal respiratory events

BACKGROUND

Obstructive sleep apnoea (OSA) is a condition leading to excessive daytime sleepiness. The aim of the study was a) to study course of daytime sleepiness in patients with OSA and b) to find the most important nocturnal polysomnography parameters influencing daytime sleepiness in OSA.

METHODS

The cohort consisted of forty-five patients (6 women, 39 men) diagnosed with OSA. All patients underwent polysomnography, Multiple Sleep Latency Test (MSLT) and rated subjectively their daytime tendency to sleep with the Epworth Sleepiness Scale.

RESULTS

Sleep latency was significantly longer at 15:00 and at 17:00 hours compared to previous tests. A significant negative correlation was found between the mean of the MSLT sleep latency and a number of awakenings, the apnoea/hypopnoea index and oxygen desaturation index values.

CONCLUSIONS

The study showed the sleep latency prolongation at 15:00 and 17:00 hours respectively and confirmed connection of excessive daytime sleepiness to fragmentation of nocturnal sleep and OSA severity.

Insomnia and limb pain in hemodialysis patients: what is the share of restless leg syndrome?

Insomnia and limb pain are common problems in dialysis patients. In addition, restless leg syndrome (RLS) as a specific cause of insomnia and limb pain has been reported in many studies. The purpose of this study was to estimate incidence of insomnia and RLS as a cause of insomnia in these patients. Twenty-six patients undergoing hemodialysis were investigated for insomnia, limb pain and RLS as per the defined criteria. They were evaluated for dialysis quality, dialysis duration, hemoglobin, serum phosphorous, ionized calcium, iron and ferritin levels. These variables between patients with insomnia and those with normal sleep were evaluated by independent "t" test. Without considering the etiology or pathogenesis of insomnia, we evaluated the occurrence of insomnia and limb pain in these patients, and specifically, restless leg syndrome. Insomnia and limb pain were common in dialytic patients. 46% of patients had insomnia. 91% of sleepless group had limb pain as a persistent, annoying complaint. Limb pain was not seen in groups with a normal sleep pattern. Restless leg syndrome was found in 8% of total cases (2 out of 26) and 17% among the insomnia group (2 out of 12). In spite of high incidence of insomnia among patients undergoing regular hemodialysis, role of RLS is trivial. There is a strong relationship between hemoglobin levels and duration of renal replacement therapy to insomnia occurrence.

Increased prevalence of restless legs syndrome in patients with acromegaly and effects on quality of life assessed by Acro-QoL

Restless legs syndrome (RLS), a neurological sensory-motor disorder characterized by a compelling urge to move the limbs during the night, is a sleep disturbance that impairs quality of life. Prevalence of RLS and consequences on quality of life were investigated in acromegalic patients. Fifty-six patients (20 men, 55.0 ± 1.6 years), 22 with active acromegaly (group 1) and 34 with controlled disease (group 2), and 95 controls (35 men, 52.9 ± 1.1 years) were evaluated by a structured sleep interview concerning insomnia, circadian sleep disorders and excessive diurnal sleepiness (EDS). The Epworth Sleepiness Scale (ESS) questionnaire was administered to those reporting EDS. Patients were investigated by RLS diagnostic interview and International Restless Leg Syndrome-Rating Scale (IRLS-RS). Quality of life was investigated by AcroQoL questionnaire. RLS was diagnosed in 21% of acromegalics and in 4% of controls (P < 0.002). Prevalence of RLS and mean IRLS-RS was higher in group 1 than in group 2 (P < 0.05). Prevalence of insomnia (P < 0.0002) and of EDS (P < 0.05) and mean ESS score (P < 0.01) were higher in RLS-positive than in RLS-free acromegalics. Video-PSG showed that mean sleep latency (P < 0.01), micro-arousal index (P < 0.05) and wakefulness after sleep onset (P < 0.01) were higher, whereas sleep efficiency (P < 0.01) was lower, in RLS-positive than in RLS-free patients. Global and physical AcroQoL scores were significantly lower in RLS-positive than in RLS-free acromegalics (P < 0.01 and P < 0.001, respectively). Prevalence and severity of RLS is increased in patients with active acromegaly and impacts negatively on their physical performances, dramatically impairing quality of life.

Prevalence of gluten sensitive enteropathy antibodies in restless legs syndrome

The prevalence of restless legs syndrome (RLS) is increased in gluten sensitive enteropathy (GSE); but prevalence of GSE is not known in RLS. 96 RLS patients and 97 healthy controls, both with or without iron deficiency were enrolled. All secondary RLS patients except iron deficiency were excluded. Subjects underwent a thorough biochemistry and routine blood analyses, and tissue transglutaminase antibodies (TTGA), endomysium antibodies (EMA) and gliadin antibodies (AGA) were also tested. In RLS patients positivity rates of all GSE antibodies were similar to those in controls. The rate of iron deficiency anaemia in RLS patients with at least one positive GSE antibody was significantly higher than that of RLS patients whose GSE antibodies were all negative. The prevalence of GSE antibodies in RLS patients is not increased. GSE might have a role in the aetiology of RLS in association with iron deficiency anaemia. Since the prevalence of GSE antibodies is not increased in RLS, it seems unlikely that GSE is involved in the aetiology of RLS through different mechanisms (e.g. immunological mechanisms) other than iron deficiency as proposed in some published papers.

[HypnoLaus sleep cohort study]

Normal sleep patterns and prevalence of sleep disorders in the general population are largely unknown. The aim of HypnoLaus cohort study is to record sleep and analyze sleep characteristics in a large population-based sample, which had undergone comprehensive genetic, somatic, and psychiatric investigations. Full polysomnography has already been performed in more than 1100 middle aged men and women randomly selected from Lausanne general population (goal 2000-3000 sleep recordings). Over 4000 additional subjects from the same population have filled various questionnaires on their sleep habits and complaints. These results combined with genetic, cardiovascular, metabolic, and psychiatric data provide a unique opportunity to determine the interaction between sleep, its genetic determinants and cardiovascular, psychiatric, or metabolic diseases.

Association studies of variants in MEIS1, BTBD9, and MAP2K5/SKOR1 with restless legs syndrome in a US population

BACKGROUND

A genome-wide association study (GWAS) identified significant association between variants in MEIS1, BTBD9, and MAP2K5/SKOR1 and restless legs syndrome (RLS). However, many independent replication studies are needed to unequivocally establish a valid genotype-phenotype association across various populations. To further validate the GWAS findings, we investigated three variants, rs2300478 in MEIS1, rs9357271 in BTBD9, and rs1026732 in MAP2K5/SKOR1 in 38 RLS families and 189 RLS patients/560 controls from the US for their association with RLS.

METHOD

Both family-based and population-based case-control association studies were carried out.

RESULTS

The family-based study showed that SNP rs1026732 in MAP2K5/SKOR1 was significantly associated with RLS (P=0.01). Case-control association studies showed significant association between all three variants and RLS (P=0.0001/OR=1.65, P=0.0021/OR=1.59, and P=0.0011/OR=1.55 for rs2300478, rs9357271, and rs1026732, respectively).

CONCLUSION

Variants in MEIS1, BTBD9, and MAP2K5/SKOR1 confer a significant risk of RLS in a US population.

A comparison of sleep disturbances and sleep apnea in patients on hemodialysis and chronic peritoneal dialysis

Studies have shown that sleep disorders are common among dialysis patients; however, few studies have compared the prevalence of different sleep disorders in patients on peritoneal dialysis (PD) and hemodialysis (HD). We used questionnaires to assess the prevalence of common sleep disorders in dialysis patients. We compared the prevalence of sleep apnea (SA) risk, restless legs syndrome (RLS), insomnia, and excessive daytime sleepiness (EDS), as well as sleep quality, in both groups. Of the 227 patients who were enrolled in the study, the total number of patients on HD was 188 (82%), while the total number of patients on PD was 39 (18%). There were no significant differences between the two groups regarding age, neck size, or duration on dialysis (all P >0.05). The estimated overall prevalence of SA was significantly higher in PD patients in comparison with HD patients (92% and 67%, respectively; P <0.05). The prevalence of insomnia was similar in both groups. The prevalence of RLS was significantly greater in PD than in HD patients (69% and 46%, respectively; P <0.05). In addition, EDS was significantly higher in PD than in HD patients (77% and 37%, respectively; P <0.05). Our study shows that sleep disorders are common in dialysis patients; however, SA, EDS, and RLS were more common in PD patients than in HD patients. Poor sleep quality and insomnia were comparable in both groups.

[Restless legs syndrome and nocturnal leg pain : Differential diagnosis and treatment]

Pain in the legs belongs to the five most frequent regional pain symptoms. Restless legs syndrome (RLS) presents a particular differential diagnosis for pain in the legs, which is characterized by a nocturnal urge to move the legs often associated with painful sensations in the legs. It is one of the most common neurological disorders and probably the leading cause of nocturnal pain in the legs. In this overview, the diagnosis and therapy of RLS as well as aspects of pain therapy of the disorder are presented. In addition, the differential diagnoses for exclusion of other specific causes of nocturnal pain in the legs are discussed.

Migraine and restless legs syndrome: is there an association?

Occasional clinical reports have suggested a link between migraine and restless legs syndrome. We undertook a systematic review of the evidence, which supports this association, and consider possible shared pathogenic mechanisms and the implications for current clinical practice.

Sleep disturbances and nocturnal agitation behaviors in older adults with dementia

STUDY OBJECTIVES

To examine nighttime sleep patterns of persons with dementia showing nocturnal agitation behaviors and to determine whether restless legs syndrome (RLS), periodic limb movements in sleep (PLMS), and obstructive sleep apnea (OSA) are associated with nocturnal agitation behaviors.

DESIGN

Cross-sectional.

SETTING

General community.

PARTICIPANTS

59 participants with geriatrician-diagnosed dementia. Participants ages ranged from 66 to 88 years (mean age 79.1; SD 6.0). Mean Mini Mental State Examination (MMSE) score was 20.1 (SD 6.6). MMSE was used to measure baseline cognitive function and not for the diagnosis of dementia.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Sleep was measured by 2 nights of in-home, attended, portable polysomnography (PSG). Nocturnal agitation was measured over 3 additional nights using the Cohen-Mansfield Agitation Inventory modified for direct observations. Two experts independently and via consensus identified probable RLS. Total sleep time in participants was 5.6 h (SD 1.8 h). Mean periodic limb movements in sleep index (PLMI) was 15.29, and a high percentage (49%) had moderate to severe obstructive sleep apnea. Probable RLS was present in 24% of participants. Those with more severe cognitive impairment had longer sleep latency. Severe cognitive impairment, low apnea hypopnea index (AHI), and probable RLS were associated with nocturnal agitation behaviors (R(2) = 0.35, F(3,55) = 9.40, P < 0.001).

CONCLUSIONS

It appears that probable RLS is associated with nocturnal agitation behaviors in persons with dementia, while OSA and PLMS are not. Further investigation is warranted to determine if treatment of RLS impacts nocturnal agitation behaviors in persons with dementia.

Restless Leg Syndrome in ADHD children: levetiracetam as a reasonable therapeutic option

The comorbidity of Attention Deficit Hyperactivity Disorder (ADHD) with sleep disorders has been extensively studied. In particular, Restless Legs Syndrome (RLS) appears to be consistently more frequent in children with ADHD. Several papers also draw attention to the frequent occurrence of epileptic seizures and EEG abnormalities in ADHD children. We performed a preliminary open label study to evaluate the efficacy of Levetiracetam (LEV) to ameliorate the sleep pattern and reduce RLS symptoms in children with a complex comorbidity between Attention Deficit Hyperactivity Disorder (ADHD), RLS and focal interictal epileptic discharges (IEDs) on EEG. We recruited seven children (all males, aged between 5 and 12years) who fulfilled the following criteria: ADHD diagnosis combined subtype; presence of idiopathic RLS; and presence of focal IEDs on EEG. All children were given LEV at a starting dose of approximately 10-20mg/kg/day followed by 10mg/kg/day incrementing at 1-week intervals up to 50-60mg/kg/day given in two separate doses. At a 3 and 6month follow-up, all children showed significant improvement (p<0.05) in global International RLS Rating Scale (IRLS-RS). Parents' reports revealed improved sleep quality with fewer awakenings and restorative sleep in their children. LEV was well tolerated and no major side effects were reported. With an accessory report we observed the reduction of epileptiform EEG activity during sleep. In most patients (6 on 7) the discharges completely disappeared; in the last patient epileptiform EEG activity was significantly reduced. These children may represent a subgroup of ADHD patients in which the hyperactivity and attention difficulties might be aggravated by sleep disturbances and by IEDs. LEV could represent a therapeutic option for these comorbid conditions.

Distressing sensations

Restless legs syndrome is not always recognised by health professionals, but the condition can adversely affect patients' lives.

[Attention deficit hyperactivity disorder and restless legs syndrome in children]

Restless legs syndrome (RLS) in the paediatric age is a common disorder and is in many cases associated to attention deficit hyperactivity disorder (ADHD). Yet, it remains 'the great unknown' in paediatrics. We do not usually think of it when examining a child with sleep problems, and there is even a tendency to deny its existence in children. ADHD and RLS have common symptoms and frequently share a common aetiopathogenesis (iron deficiency anaemia). Although important progress has been made in recent years in the research conducted on both disorders, further studies must be carried out to examine different treatments or other aspects of RLS in the paediatric population.

Restless legs syndrome in patients on hemodialysis

Restless legs syndrome (RLS) is common among dialysis patients, with a reported prevalence of 6-60%. The prevalence of RLS in Syrian patients on hemodialysis (HD) is not known. The purpose of this study is to determine the prevalence of RLS in patients on regular HD, and to find the possible correlation between the presence of RLS and demographic, clinical, and biochemical factors. One hundred and twenty-three patients (male/female = 70/53, mean age = 41.95 ± 15.11 years) on HD therapy at the Aleppo University Hospital were enrolled into the study. RLS was diagnosed based on criteria established by the International Restless Legs Syn-drome Study Group (IRLSSG). Data procured were compared between patients with and without RLS. Applying the IRLSSG criteria for the diagnosis, RLS was seen in 20.3% of the study pa-tients. No significant difference in age, gender, and intake of nicotine and caffeine was found between patients with and without the RLS. Similarly, there was no difference between the two groups in the duration of end-stage renal disease (ESRD), the period of dialysis dependence, dialysis adequacy, urea and creatinine levels, and the presence of anemia. The co-morbidities and the use of drugs also did not differ in the two groups. Our study suggests that the high prevalence of RLS among patients on HD requires careful attention and correct diagnosis can lead to better therapy and better quality of life. The pathogenesis of RLS is not clear and further studies are required to identify any possible cause as well as to discover the impact of this syndrome on sleep, quality of life, and possibly other complications such as cardiovasculare disease.

Cluster headache patients are not affected by restless legs syndrome: an observational study

OBJECTIVE

To investigate the presence of Restless Legs Syndrome (RLS) in Cluster Headache (CH) patients compared to headache-free controls.

DESIGN AND SETTING

Cross-sectional case-control study of CH patients presenting at tertiary headache centers over the period January-December 2008.

PATIENTS AND PARTICIPANTS

Fifty consecutive patients (6 women and 44 men) of mean age of 39.7 year (standard deviation 10.9) with episodic or chronic CH diagnosed according to ICHD-II criteria and 50 headache-free subjects matched by age and sex were recruited.

RESULTS

None of the CH patients had RLS. Six (12%) headache-free controls had RLS.

CONCLUSIONS

Our data indicate no probable relationship between CH and RLS. However, since both conditions have a circadian rhythm and are associated with altered melatonin secretion, we conjecture that reduced nocturnal melatonin in CH likely allows sustained dopaminergic activity which could be protective against RLS in CH patients.

Restless legs syndrome in subjects with a knee prosthesis: evidence that symptoms are generated in the periphery

OBJECTIVE

There are no data adressing the prevalence of restless legs syndrome in subjects who have knee prosthesis. Therefore, we conducted a cross-sectional survey of subjects who underwent knee prosthesis surgery.

METHOD

A total of 107 subjects (30 male, 77 female) were interviewed over the telephone regarding restless legs syndrome symptoms. If the patients exhibited symptoms of the syndrome, we conducted face-to-face interviews. Lastly, a therapeutic test with pramipexole was proposed for each subject.

RESULTS

In our cohort, 7 males (23%) and 30 females (39%) had restless legs syndrome. Of these, 6 males and 23 females were submitted to face-to-face-interview. Of the males, 5 (83%) had restless legs after the knee surgery-exclusively in the operated leg- and reported no family restless legs history. One man had a prior case of bilateral restless legs syndrome, a positive family history and claimed exacerbation of symptoms in the operated leg. Among the females, 16 (69%) had restless legs prior to surgery. A total of 10 female patients reported bilateral symptoms, with fewer symptoms in the operated leg, while 6 displayed a worse outcome in the operated leg. The 7 females (31%) without restless legs prior to surgery and without a family history experienced symptoms only in the operated leg. All subjects responded favorably to the pramipexole therapeutic test.

CONCLUSION

Our results suggest that secondary unilateral restless legs syndrome may ensue from knee prosthesis surgery and that the symptoms are generated in the peripheral nervous system.

Impact of inadequate sleep on unintentional injuries in adolescents

Excessive daytime sleepiness is a growing societal problem in adolescents. Empirical evidence demonstrates that adolescents experience significant sleepiness as a result of inadequate or disrupted sleep. Although the functional impairment caused by sleepiness in the pediatric population is less studied, children and adolescents do experience changes in behavior and a decline in performance as seen in the adult population. The end result is functional impairment in adolescents, which then places them at higher risk for unintentional injury.