Denise Sharon

Bio: Denise Sharon is an academic researcher from Tulane University. The author has contributed to research in topics: Restless legs syndrome & Rating scale. The author has an hindex of 9, co-authored 17 publications receiving 1697 citations.

Periodic limb movements in sleep and iron status in children.

Abstract: STUDY OBJECTIVES To assess potential relationships between serum iron and ferritin levels and the severity of periodic limb movement in sleep (PLMS) in a pediatric population, and to evaluate the response to supplemental iron therapy. DESIGN A prospective study of all consecutively diagnosed children with PLMS (periodic limb movement index [periodic limb movements per hour of total sleep time, [PLMI] > 5) who underwent overnight polysomnographic evaluation. In all patients, complete blood count and serum iron and ferritin levels were obtained. Patients with serum ferritin concentrations less than 50 microg/L were prescribed iron sulfate at 3 mg/kg of elemental iron per day for 3 months. At the end of treatment, serum iron and ferritin levels and sleep studies were repeated. SETTING Comprehensive Sleep Medicine Center, Tulane University Health Sciences Center, and Kosair Children's Hospital Sleep Medicine and Apnea Center. PATIENTS Twenty boys and 19 girls with PLMS with a mean age of 7.5 +/- 3.1 years. INTERVENTION Iron therapy. RESULTS Twenty-eight (71.8%) patients had ferritin levels less than 50 microg/L. There was no significant correlation between serum ferritin concentration and PLMS severity as indicated by the PLMI (r = -0.19). The PLMI in patients with serum ferritin levels less than 50 microg/L (29.9 +/- 15.5 PLM/h) was higher than in patients with serum ferritin levels greater than 50 microg/L (21.9 +/- 11.8 PLM/h); however, the difference did not achieve statistical significance (P = 0.09). In contrast, serum iron was significantly correlated with PLMI (r = -0.43, P < 0.01). Indeed, patients with serum iron concentrations less than 50 microg/dL had a higher PLMI compared to patients with serum iron concentrations greater than 50 microg/dL (42.8 +/- 18.3 PLM/h and 23.1 +/- 10.1 PLM/h, respectively; P = 0.02). Twenty-five out of the 28 PLMS patients with serum ferritin levels less than 50 microg/L received treatment with iron sulfate, and 19 (76%) responded favorably. Among the responders to iron therapy, PLMI decreased from 27.6 +/- 14.9 PLM per hour to 12.6 +/- 5.3 PLM per hour after 3 months of iron supplements (P < 0.001) and coincided with increases in serum ferritin levels (pre: 40.8 +/- 27.4 microg/L vs post: 74.1 +/- 13.0 microg/L; P < 0.001). CONCLUSIONS In children, the presence of PLMS is frequently associated with low serum iron and a tendency toward low serum ferritin levels. In addition, iron therapy is associated with clinical improvement in most of these patients.

Effect of Supplemental Oxygen on Sleep Architecture and Cardiorespiratory Events in Preterm Infants

Abstract: Objective. To investigate the effect of low-flow supplemental oxygen (SupOx) on sleep architecture and cardiorespiratory events in asymptomatic preterm infants. Methods. An overnight polysomnographic evaluation was conducted prospectively in 23 premature infants who were born at 30.0 ± 3.2 (standard deviation) weeks’ gestational age and studied at 38.1 ± 4.4 weeks’ postconceptional age. Infants were free of any adverse events, including cardiorespiratory monitor alarms in the nursery for at least 1 week before the study. Infants received room air (RA) or SupOx via nasal cannula at 0.25 L/min. Results. Quiet sleep density was increased during SupOx (33.3 ± 10.8% vs 26.6 ± 10.0% total sleep time [TST] in RA), and a reciprocal decrease in active sleep density was observed (61.5 ± 11.1% vs 68.4 ± 9.9% TST in RA). No differences in sleep efficiency emerged (69.7 ± 10.6% SupOx vs 69.7 ± 8.8% RA). SupOx elicited significant decreases in apnea index (3.8 ± 2.4 events/h vs 11.1 ± 6.4 events/h in RA) and in the percentage of time spent in periodic breathing (1.8 ± 2.9% vs 6.7 ± 8.9% in RA). In addition, SupOx decreased the frequency of bradycardic events (0.3 ± 0.8 events vs 2.5 ± 0.03 events in RA) and improved overall oxygen saturation (98.7 ± 1.1% vs 96.4 ± 2.2%). No changes in alveolar ventilation, as derived from end-tidal CO2 measurements, was detected (38.6 ± 5.8 mm Hg in SupOx vs 38.4 ± 5.4 mm Hg in RA). Conclusions. Asymptomatic preterm infants exhibit frequent and potentially clinically adverse cardiorespiratory events when assessed in the sleep laboratory. Administration of SupOx to these infants is associated with an increase in the overall duration and percentage TST spent in quiet sleep with reciprocal changes in active sleep. In addition, improvement in respiratory stability is observed with the use of low-flow SupOx, as evidenced by a decrease in apnea, periodic breathing, and bradycardia, without adverse effects on alveolar ventilation.

Encouraging initial response of restless legs syndrome to pramipexole.

Abstract: Restless legs syndrome (RLS) is a common condition that results in uncomfortable sensations and an urge to move the limbs. Two centers tested a new dopamine agonist, pramipexole, in 23 patients with RLS in a time-limited, open-label, clinical trial. After 4 weeks or more, 19 patients reported significant improvement as assessed by the short International Restless Legs Syndrome Study Group questionnaire (p < 0.0001). These encouraging preliminary results justify larger, controlled trials for pramipexole in patients with RLS.

Mood disorders in restless legs syndrome (Willis-Ekbom disease).

Abstract: OBJECTIVE Restless legs syndrome (RLS), also known as Willis-Ekbom disease, is a sensorimotor disorder that can result in considerable sleep disruption. This narrative review provides an overview of RLS diagnosis and reports epidemiologic evidence for an association between RLS and mood disorders. Possible links between RLS, sleep disturbances, and mood disorders are considered, and theoretical pathophysiologic pathways are discussed. Finally, pharmacologic therapies for RLS are summarized. DATA SOURCES A PubMed search was performed using the search term restless legs syndrome in combination with affective/anxiety, antidepressants, anxiety/anxiety disorder, attention deficit hyperactivity disorder, depression/depressive disorder, mood/mood disorder, neuropsychiatric, panic/panic disorder, psychiatric disorder, and psychosis. English-language articles published between January 1993 and May 2013 were retrieved. Additional studies were identified from the reference lists of relevant publications. STUDY SELECTION 173 publications were retrieved. Articles related to the association between idiopathic RLS and depression, anxiety, and mood disorders were reviewed. In total, 32 epidemiologic studies were identified. These studies were reviewed in detail and ranked according to quality. DATA EXTRACTION Data were extracted on the basis of relevance to the topic. Epidemiologic studies were assessed using 3 parameters: methodology, data quality, and generalizability of the results. Each factor was scored from 1 (high quality) to 4 (low quality), giving a total score of between 3 and 12 for each study. RESULTS AND CONCLUSIONS RLS and mood disorders are frequently comorbid. Recognition and appropriate treatment of comorbid RLS are particularly important in patients with psychiatric disorders, as RLS is a common medical reason for insomnia, and antidepressant use may exacerbate sensory symptoms.

Medscape

Abstract: Secret History: Return of the Black Death Channel 4, 7-8pm In 1348 the Black Death swept through London, killing people within days of the appearance of their first symptoms. Exactly how many died, and why, has long been a mystery. This Secret History documentary follows experts as they pick through the evidence and reveal why the plague killed on such a scale. And they ask, what might be coming next?

Systematic review of levodopa dose equivalency reporting in Parkinson's disease

Abstract: Interpretation of clinical trials comparing different drug regimens for Parkinson's disease (PD) is complicated by the different dose intensities used: higher doses of levodopa and, possibly, other drugs produce better symptomatic control but more late complications. To address this problem, conversion factors have been calculated for antiparkinsonian drugs that yield a total daily levodopa equivalent dose (LED). LED estimates vary, so we undertook a systematic review of studies reporting LEDs to provide standardized formulae. Electronic database and hand searching of references identified 56 primary reports of LED estimates. Data were extracted and the mean and modal LEDs calculated. This yielded a standardized LED for each drug, providing a useful tool to express dose intensity of different antiparkinsonian drug regimens on a single scale. Using these conversion formulae to report LEDs would improve the consistency of reporting and assist the interpretation of clinical trials comparing different PD medications.

Practice parameters for the indications for polysomnography and related procedures: an update for 2005.

Abstract: These practice parameters are an update of the previously-published recommendations regarding the indications for polysomnography and related procedures in the diagnosis of sleep disorders. Diagnostic categories include the following: sleep related breathing disorders, other respiratory disorders, narcolepsy, parasomnias, sleep related seizure disorders, restless legs syndrome, periodic limb movement sleep disorder, depression with insomnia, and circadian rhythm sleep disorders. Polysomnography is routinely indicated for the diagnosis of sleep related breathing disorders; for continuous positive airway pressure (CPAP) titration in patients with sleep related breathing disorders; for the assessment of treatment results in some cases; with a multiple sleep latency test in the evaluation of suspected narcolepsy; in evaluating sleep related behaviors that are violent or otherwise potentially injurious to the patient or others; and in certain atypical or unusual parasomnias. Polysomnography may be indicated in patients with neuromuscular disorders and sleep related symptoms; to assist in the diagnosis of paroxysmal arousals or other sleep disruptions thought to be seizure related; in a presumed parasomnia or sleep related seizure disorder that does not respond to conventional therapy; or when there is a strong clinical suspicion of periodic limb movement sleep disorder. Polysomnography is not routinely indicated to diagnose chronic lung disease; in cases of typical, uncomplicated, and noninjurious parasomnias when the diagnosis is clearly delineated; for patients with seizures who have no specific complaints consistent with a sleep disorder; to diagnose or treat restless legs syndrome; for the diagnosis of circadian rhythm sleep disorders; or to establish a diagnosis of depression.