An expert panel delphi consensus statement on patient selection and management for transitioning between oral and inhaled treprostinil

Treprostinil, a prostacyclin analogue used in the treatment of pulmonary arterial hypertension (PAH), is available for administration by parenteral, oral, or inhaled routes. Transitioning between routes may be beneficial for appropriate patients; however, there is little published data on transitions between oral and inhaled treprostinil. We used a modified Delphi process to develop expert consensus recommendations on transitions between these formulations. Three questionnaires were used to develop statements about relevant aspects of transition management, which the panelists rated, using a Likert scale, from -5 (strongly disagree) to +5 (strongly agree). Eleven physicians with expertise in PAH treatment modalities, participated in the panel. Of the 492 statements evaluated, consensus was reached on 215 (43.7%). Key consensus recommendations included (1) accurately defining successful transition, as stable or improved PAH with good tolerability and adherence, and (2) patients with stable, low-risk PAH showing insufficient response or tolerability to their existing treprostinil therapy (and due to restrictions in up titration of dosing), as appropriate candidates for transitions between treprostinil formulations. Panelists did not reach consensus for an overall strategy for performing these transitions, mainly because of variability in their practice parameters. Consensus was also achieved on recommendations for adverse event management, including reassurance, administration of oral treprostinil 3 times daily with food, and dosing inhaled treprostinil at intervals ≥3 hours apart. The Delphi process aided in developing expert consensus recommendations that may provide clinically useful guidance for transitioning between treprostinil formulations. However, additional data from centers with high volumes of PAH patients undergoing treprostinil transitions would be optimal for defining more complete and robust strategies to facilitate successful transition.

1001 Intravenous Ferric Carboxymaltose For Restless Legs Syndrome In Children And Adolescents

Introduction

Substantial scientific evidence implicates brain iron deficiency in the pathophysiology of restless legs syndrome (RLS). Current clinical guidelines recommend oral and intravenous iron (IV) in the treatment of both adult and pediatric RLS but studies using ferric carboxymaltose (FCM) are lacking in children and adolescents.

Methods

Retrospective case series of children and adolescents with RLS treated with IV FCM who had serum ferritin levels <50 μg/L. Patients were offered a single dose of IV FCM, 15 mg/kg if weighting <50 kg or 750 mg if weighting >50 kg. Iron profile, serum ferritin, and severity assessment by the International Restless Legs Study Group severity scale (IRLS) were collected pre- and post-infusion. Clinical Global Impression Scale (CGI) was used instead of the IRLS for children. Phosphorus level and adverse effects were assessed post-infusion in all patients. Age and sex-matched children with RLS treated with oral iron supplementation (mean dosage 1.5±0.62 mg/kg/day) were included as a comparison group.

Results

Twenty-eight subjects (15 females, mean age 11.5 years, SD 4.23) and 24 controls were included. Baseline ferritin levels were not significantly different from those of controls but increased significantly from 13.9±7.02 to 112.9±12.00 μg/L after 8 weeks from infusion (p<0.000001), when they were also significantly higher than control values (34.2±21.64 μg/mL, p<0.000001). Transferrin saturation increased from 22.8±9.77% to 31.7±6.81% (p<0.0001), total iron binding capacity decreased from 366.7±51.32 to 302.0±37.83 μg/dL (p<0.0000035). RLS was reported to be resolved or improved in all children treated with IV iron (vs. 62.5% of controls) while none of them reported no change (vs. 37.5% of controls; Chi-square test 9.84, p<0.002). IRLS Score decreased in adolescents from 30.7±22.68 to 3.2±4.21 (p<0.000008) while CGI-I was “very much improved” in six children and “much improved” in four. Side effects were reported in 17.8% of patients treated IV and 20.8% controls (Chi-square 0.0169, p=0.897). FCM side effects included lightheadedness and gastrointestinal discomfort. Post IV phosphorus levels were normal in all participants.

Conclusion

This open-label, observational and retrospective study indicates that FCM IV infusion is an effective treatment for pediatric RLS with higher efficacy than oral iron supplementation.

Support

 

Recommendations for the use of oral treprostinil in clinical practice: a Delphi consensus project pulmonary circulation

Oral treprostinil was recently labeled for treatment of pulmonary arterial hypertension. Similar to the period immediately after parenteral treprostinil was approved, there is a significant knowledge gap for practicing physicians who might prescribe oral treprostinil. Despite its oral route of delivery, use of the drug is challenging because of the requirement for careful titration and management of drug-related adverse effects. We aimed to create a consensus document combining available evidence with expert opinion to provide guidance for use of oral treprostinil. Following a methodology commonly used in business and social sciences (the 'Delphi Process'), two investigators from the oral treprostinil (Freedom) studies created a series of statements based on available evidence and the package insert. The set of 'best practice' statements was circulated to nine other Freedom trial investigators. Their comments were incorporated into the document as new line items for further vote and comment. The subsequent document was put to vote line by line (scale of -5 to +5) and a final statement was drafted. Consensus recommendations include initial therapy with 0.125 mg for treatment naÿ patients, three times daily dosing, aggressive use of antidiarrheal medication, and a strong preference for use of the drug in combination with other approved PAH therapies. This process was particularly valuable in providing guidance for the management of adverse events (where essentially no data is available). The Delphi process was useful to codify investigator experience and subsequently develop investigator consensus about practical issues for physicians who may wish to prescribe oral treprostinil.

Balloon dilation atrial septostomy for advanced pulmonary hypertension in patients on prostanoid therapy

BACKGROUND

Prostanoid therapy improves quality of life and may increase survival in patients with advanced pulmonary hypertension (PH). Balloon dilated atrial septostomy (BDAS) can palliate or bridge to transplantation for patients resistant to medical therapy. The safety and efficacy of BDAS in the prostanoid era has not previously been reported.

METHODS

All patients had progressive symptoms despite prostanoid therapy at the time of their first BDAS. Sixteen patients who underwent a total of 23 septostomies between 2004 and 2014 were included in this retrospective case series.

RESULTS

Patients were aged 47.6 years ± 11.3 with 12/16 women. Etiologies included idiopathic (7), methamphetamine (6), scleroderma (1), and anorexigen (2). One patient died within 24 hr post-procedure. Thirty-day and 1-year survival were 75% and 64%, respectively. Six of the septostomies were revisions, including two which were ultimately stented. Three subjects were successfully bridged to transplant. Pulmonary capillary wedge pressure (PCWP) increased from a mean of 13 to 17 mm Hg, cardiac index increased from 2.1 to 2.4 L/min/m(2) , and arterial saturation decreased from 90.7 ± 4.3 to 82.5 ± 5.6%. All non-survivors at 30 days were male and had higher baseline serum creatinine, mean RAP, right ventricular end diastolic pressure (RVEDP), and left ventricle (LV) filling pressures, and lower right ventricle (RV) ejection fraction. Mortality was associated with unchanged post-septostomy cardiac output despite an increase in left ventricular end diastolic pressure (LVEDP).

CONCLUSIONS

BDAS may be an alternate therapy for select PH patients who have symptomatic progression despite prostanoid therapy. Survival is comparable to prior reports of BDAS in the pre-prostanoid era.

Diverse forms of pulmonary hypertension remodel the arterial tree to a high shear phenotype

Pulmonary hypertension (PH) is associated with progressive changes in arterial network complexity. An allometric model is derived that integrates diameter branching complexity between pulmonary arterioles of generation n and the main pulmonary artery (MPA) via a power-law exponent (X) in dn = dMPA2(-n/X) and the arterial area ratio β = 2(1-2/X). Our hypothesis is that diverse forms of PH demonstrate early decrements in X independent of etiology and pathogenesis, which alters the arteriolar shear stress load from a low-shear stress (X > 2, β > 1) to a high-shear stress phenotype (X < 2, β < 1). Model assessment was accomplished by comparing theoretical predictions to retrospective morphometric and hemodynamic measurements made available from a total of 221 PH-free and PH subjects diagnosed with diverse forms (World Health Organization; WHO groups I-IV) of PH: mitral stenosis, congenital heart disease, chronic obstructive pulmonary lung disease, chronic thromboembolism, idiopathic pulmonary arterial hypertension (IPAH), familial (FPAH), collagen vascular disease, and methamphetamine exposure. X was calculated from pulmonary artery pressure (PPA), cardiac output (Q) and body weight (M), utilizing an allometric power-law prediction of X relative to a PH-free state. Comparisons of X between PAH-free and PAH subjects indicates a characteristic reduction in area that elevates arteriolar shear stress, which may contribute to mechanisms of endothelial dysfunction and injury before clinically defined thresholds of pulmonary vascular resistance and PH. We conclude that the evaluation of X may be of use in identifying reversible and irreversible phases of PH in the early course of the disease process.

Diurnal variations in brain iron concentrations in BXD RI mice

Under normal and dietary iron deficiency conditions, the BXD recombinant inbred (RI) strains of mice show large variations in regional brain iron concentration, particularly in the ventral midbrain (VMB). In a study utilizing just one of the BXD strains, diurnal changes in subregional brain iron concentration were found, which were dependent on the brain region and sex of the mice. The focus of this study was to determine if diurnal changes in VMB can be found across other BXD RI strains and whether a diurnal effect would be common to all strains or variable across strains similar to the large strain variability in iron concentrations determined during the first part of the light phase. Eight RI (BXD type) strains of mice of both sexes were selected for this study. Mice were sacrificed at postnatal day 120: half in the light phase (LP) and half in the dark phase (DP) of the light-dark cycle. Iron concentrations were determined in VMB, which was the primary region of interest, and five other brain regions. Exploratory analysis was also done on liver and spleen iron concentrations to assess for diurnal changes. Three strains showed clear diurnal variation in iron in the VMB and the others strains showed diurnal variations in other regions. These changes were not equally apparent in both sexes. Exploratory analysis also found strain×sex-dependent diurnal differences in spleen and liver iron. In conclusion, significant brain-regional-specific diurnal changes in total iron concentrations were found in a selection of BXD RI mice. Sex and strain are functional determinates of which regions will be affected and in what direction the affect will be. The study provides an animal model for future work into determining the biological and genetic basis of circadian influences on VMB iron homeostasis.

Iron deficiency alters expression of dopamine-related genes in the ventral midbrain in mice

A clear link exists between iron deficiency (ID) and nigrostriatal dopamine malfunction. This link appears to play an important role in at least restless legs syndrome (RLS) if not several other neurological diseases. Yet, the underlying mechanisms remain unclear. The effects of ID on gene expression in the brain have not been studied extensively. Here, to better understand how exactly ID alters dopamine functioning, we investigated the effects of ID on gene expression in the brain, seeking to identify any potential transcription-based mechanisms. We used six strains of recombinant inbred mice (BXD type) known to differ in susceptibility to ID in the brain. Upon weaning, we subjected mice from each strain to either an iron-deficient or iron-adequate diet. After 100 days of dietary treatment, we measured the effects of ID on gene expression in the ventral midbrain, a region containing the substantia nigra. The substantia nigra is the base of the nigrostriatal dopamine pathway and a region particularly affected by iron loss in RLS. We screened for ID-induced changes in expression, including changes in that of both iron-regulating and dopamine-related genes. Results revealed a number of expression changes occurring in ID, with large strain-dependent differences in the genes involved and number of expression changes occurring. In terms of dopamine-related genes, results revealed ID-induced expression changes in three genes with direct ties to nigrostriatal dopamine functioning, two of which have never before been implicated in an iron-dopamine pathway. These were stromal cell-derived factor 1 (Cxcl12, or SDF-1), a ferritin regulator and potent dopamine neuromodulator, and hemoglobin, beta adult chain 1 (Hbb-b1), a gene recently shown to play a functional role in dopaminergic neurons. The extent of up-regulation of these genes varied by strain. This work not only demonstrates a wide genetic variation in the transcriptional response to ID in the brain, but also reveals two novel biochemical pathways by which iron may potentially alter dopamine function.

Effects of IV iron isomaltoside-1000 treatment on regional brain iron status in an iron-deficient animal

BACKGROUND

Iron deficiency has been documented to affect human cognitive function and conditions with brain iron compromise such as the restless legs syndrome (RLS). Intravenous (IV) iron treatment is used to reduce iron deficiency but its effects on brain iron are not known. It is not known if IV iron is effective in correcting regional brain iron deficiencies nor if it poses a risk of producing iron overload in some brain regions. Preclinical study of IV iron in the iron-deficient (ID) murine model is needed to evaluate and develop IV iron treatments for brain iron deficiency.

METHODS

Response to tail vein injections of iron (iron isomaltoside-1000, dose equivalent to 1000 mg for 75 kg adult) or vehicle were evaluated for ID mice by microdialysis assessing non-transferrin bound (NTB) iron in the ventral midbrain (VMB) and autopsy at 3 and 10 days post-injection assessing iron content in critical brain regions.

RESULTS

The ID mice showed marked circadian variation in NTB extracellular iron. After iron injection, NTB iron was rapidly increased in the VMB and then decreased over 12h to the levels observed for vehicle. Regional brain iron content at 3 and 10 days post-injection in the iron- compared to vehicle-treated group showed significantly more iron for the VMB and nucleus accumbens but not for the other regions (i.e. prefrontal cortex, caudate-putamen, cerebellum, and pons), which also did not show decreased iron content with the ID diet.

CONCLUSION

Iron isomaltoside-1000 given IV corrects the regional brain iron deficiency in these ID mice without producing iron overload in any of the brain regions studied. This is the first demonstration of effects of IV iron in the brain and it provides a useful preclinical model for this assessment, particularly relevant for developing iron treatments for conditions with problematic iron deficiency, e.g. RLS.

6.6-hour inhalation of ozone concentrations from 60 to 87 parts per billion in healthy humans

RATIONALE

Identification of the minimal ozone (O(3)) concentration and/or dose that induces measurable lung function decrements in humans is considered in the risk assessment leading to establishing an appropriate National Ambient Air Quality Standard for O(3) that protects public health.

OBJECTIVES

To identify and/or predict the minimal mean O(3) concentration that produces a decrement in FEV(1) and symptoms in healthy individuals completing 6.6-hour exposure protocols.

METHODS

Pulmonary function and subjective symptoms were measured in 31 healthy adults (18-25 yr, male and female, nonsmokers) who completed five 6.6-hour chamber exposures: filtered air and four variable hourly patterns with mean O(3) concentrations of 60, 70, 80, and 87 parts per billion (ppb).

MEASUREMENTS AND MAIN RESULTS

Compared with filtered air, statistically significant decrements in FEV(1) and increases in total subjective symptoms scores (P < 0.05) were measured after exposure to mean concentrations of 70, 80, and 87 ppb O(3). The mean percent change in FEV(1) (+/-standard error) at the end of each protocol was 0.80 +/- 0.90, -2.72 +/- 1.48, -5.34 +/- 1.42, -7.02 +/- 1.60, and -11.42 +/- 2.20% for exposure to filtered air and 60, 70, 80, and 87 ppb O(3), respectively.

CONCLUSIONS

Inhalation of 70 ppb O(3) for 6.6 hours, a concentration below the current 8-hour National Ambient Air Quality Standard of 75 ppb, is sufficient to induce statistically significant decrements in FEV(1) in healthy young adults.

Of mice and men, periodic limb movements and iron: how the human genome informs the mouse genome

The gene, BTBD9, was recently linked to restless legs syndrome, periodic limb movements and iron status in humans. In a homologous region in mouse, an area containing btbd9 was also identified as being related to iron homeostasis. This finding is important as iron status in brain has been implicated in restless legs syndrome.

Restless Legs Syndrome and the five-factor model of personality: results from a community sample

OBJECTIVE

To examine personality characteristics as potential mediators of the association between Restless Legs Syndrome (RLS) and psychiatric disorders.

METHOD

Revised NEO Personality Inventory traits are compared in respondents with (n=42) versus without (n=982) a diagnosis of RLS in a general population sample.

RESULTS

RLS was associated with higher neuroticism after adjusting for potential confounders, including current psychopathology. Further analysis showed that the association between RLS and neuroticism contributes to, but does not fully explain, the relationship between RLS and either panic disorder or major depression.

CONCLUSIONS

Neuroticism may mediate part of the relationship between RLS and depression or panic, but the mechanisms of these associations need further exploration.

Do airway metallic stents for benign lesions confer too costly a benefit?

Background

The use of self-expanding metallic stents (SEMAS) in the treatment benign airway obstruction is controversial.

Methods

To evaluate the safety and efficacy of SEMAS for this indication, we conducted a 10-year retrospective review at our tertiary medical centre.

Results

Using flexible bronchoscopy, 82 SEMAS (67% Ultraflex, 33% Wallstent) were placed in 35 patients with inoperable lesions, many with significant medical comorbidities (88%). 68% of stents were tracheal, and 83% of patients showed immediate symptomatic improvement. Reversible complications developed in 9% of patients within 24 hrs of stent placement. Late complications (>24 hrs) occurred in 77% of patients, of which 37% were clinically significant or required an interventional procedure. These were mainly due to stent migration (12.2%), fracture (19.5%), or obstructive granulomas (24.4%). The overall granuloma rate of 57% was higher at tracheal sites (59%) than bronchial ones (34%), but not significantly different between Ultraflex and Wallstents. Nevertheless, Wallstents were associated with higher rates of bleeding (5% vs. 30%, p = 0.005) and migration (7% vs. 26%, p = 0.026). Of 10 SEMAS removed using flexible bronchoscopy, only one was associated with incomplete removal of fractured stent wire. Median survival was 3.6 ± 2.7 years.

Conclusion

Ill patients with inoperable lesions may be considered for treatment with SEMAS.

Medication use in patients with restless legs syndrome compared with a control population

Primary restless legs syndrome (RLS) is a sensorimotor disorder causing chronic sleep deprivation in those with moderate to severe symptoms. It has been associated with other medical conditions, such as high blood pressure, depression and attention deficit hyperactive disorder (ADHD). If these conditions are more prevalent for RLS patients, then it would be expected RLS patients would use relatively more of the medications treating these conditions. Current medication use was obtained from 110 RLS patients and 54 age, race and gender-matched local-community controls. Each subject was diagnosed as primary RLS or having no indications for RLS by a clinician board-certified in sleep medicine. The RLS group used more medications than the control group even when medications used for treating RLS were excluded. Significantly more of the RLS patients than controls used anti-depressants, gastro-intestinal (GI) medications and asthma/allergy medications. RLS patients compared with those without RLS are more likely to use medications not related to treating RLS. Moreover they use medications for conditions that have not previously been considered related to RLS, i.e. GI and asthma/allergy conditions.

Transition from IV epoprostenol to subcutaneous treprostinil in pulmonary arterial hypertension: a controlled trial

BACKGROUND

We determined the relative efficacy of subcutaneous (SC) treprostinil in stable World Health Organization class II and III patients transitioned from IV epoprostenol.

METHODS

This was an 8-week, multicenter, randomized study in which patients were transitioned from IV epoprostenol to SC treprostinil or placebo over a period of up to 14 days and monitored carefully during and after the transition period for signs of deterioration. Patients with clinical deterioration were returned promptly to epoprostenol. Placebo or SC treprostinil doses were titrated in response to symptoms. Time to adjudicated clinical deterioration was compared between treatment groups, and exercise capacity, symptoms of disease, and safety were assessed throughout the study.

RESULTS

Twenty-two patients were enrolled and completed the study. Seven of 8 patients (88%) [corrected] withdrawn to placebo had clinical deterioration, while only 1 of 14 patients (7%) [corrected] withdrawn to SC treprostinil had clinical deterioration (p = 0.00023 based on a treatment comparison of time to deterioration). Analyses of exercise capacity and symptoms strongly supported the efficacy of SC treprostinil in epoprostenol-treated patients. Adverse events consisted of painful infusion site reactions and anticipated prostacyclin side effects.

CONCLUSIONS

SC treprostinil is effective in pulmonary arterial hypertension and prevents clinical deterioration and maintains functional status in patients transitioned from epoprostenol.

Decreased transferrin receptor expression by neuromelanin cells in restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) is a sensory-movement disorder affecting 5 to 10% of the population. Its etiology is unknown, but MRI analyses and immunohistochemical studies on autopsy tissue suggest the substantia nigra (SN) of patients with RLS has subnormal amounts of iron.

METHODS

Neuromelanin cells from the SN of four RLS and four control brains were isolated by laser capture microdissection, and a profile of iron-management protein expression was obtained by immunoblot analysis. Binding assays for iron regulatory protein activity were performed on cell homogenates.

RESULTS

Ferritin, divalent metal transporter 1, ferroportin, and transferrin receptor (TfR) were decreased in RLS neuromelanin cells compared with control. Transferrin was increased in RLS neuromelanin cells. This protein profile in RLS neuromelanin cells is consistent with iron deficiency with the exception that TfR expression was decreased rather than increased. The concentration and activity of the iron regulatory proteins (IRP1 and IRP2) were analyzed to determine whether there was a functional deficit in the post-transcriptional regulatory mechanism for TfR expression. Total IRP activity, IRP1 activity, and IRP1 protein levels were decreased in RLS, but total IRP2 protein levels were not decreased in RLS.

CONCLUSION

Restless legs syndrome may result from a defect in iron regulatory protein 1 in neuromelanin cells that promotes destabilization of the transferrin receptor mRNA, leading to cellular iron deficiency.

Bronchiolitis obliterans

Bronchiolitis obliterans (BO) is a disease of small airways that results in progressive dyspnea and airflow limitation. It is a common sequela of bone marrow, lung, and heart-lung transplantation, but can also occur as a complication of certain pulmonary infections, adverse drug reaction, toxic inhalation, and autoimmune disorders. Non-transplant-related BO is rare and can mimic asthma and chronic obstructive pulmonary disease (COPD). In transplant-related BO, the diagnosis can be suggested by obstructive changes in serial pulmonary function testings, while open lung biopsy is usually required in non-transplant cases. High-resolution computerized tomography (HRCT) is also a helpful tool to diagnose and assess the severity of BO. The treatment of BO, regarding of the cause, is usually disappointing. Systemic corticosteroid immunosuppression and retransplantation have been described with variable success.

Validation of the Restless Legs Syndrome Quality of Life Instrument (RLS-QLI): findings of a consortium of national experts and the RLS Foundation

This study was designed to assess the initial psychometric properties of a new disease-specific health-related quality of life (HRQL) measure, the Restless Legs Syndrome (RLS) Quality of Life Instrument (RLS-QLI).

METHODS

Draft items were generated from a literature review, consultation with MD and PhD specialists in the fields of neurology and sleep medicine, and input from two patient focus groups. The initial item reduction was accomplished using a survey of 392 persons with self-reported RLS symptoms from the membership of the RLS Foundation. The final (independent) validation sample consisted of 574 of persons on the RLS Foundation's Interest Group List Serve who also reported having RLS. The mean age of participants was 54.5 (SD 12.3), with a sex ratio of 1M:2F, and the majority was on some form of medication for RLS (66%).

RESULTS

Four factors were identified (Daily Function, Social Function, Sleep Quality, and Emotional Well-Being) consisting of 17 items that explained 73.3% of the total variance. Each scale had good internal consistency (Cronbach's alpha's between 0.85 and 0.91) and 2-week test retest stability (Pearson Correlations between 0.81 and 0.93). Convergent validity was demonstrated using related scales on the SF-36 (r = 0.47-0.60) and criterion-related validity was shown using the clinical IRLS Scale of Symptom Severity (r = -0.45 to -0.77).

CONCLUSION

The RLS-QLI is a valid disease-specific HRQL instrument that will contribute to our understanding of how RLS impacts the lives of those affected with this CNS disorder.

Neuropathological examination suggests impaired brain iron acquisition in restless legs syndrome

OBJECTIVE

To assess neuropathology in individuals with restless legs syndrome (RLS).

METHODS

A standard neuropathologic evaluation was performed on seven brains from individuals who had been diagnosed with RLS. The substantia nigra was examined in greater detail for iron staining and with immunohistochemistry for tyrosine hydroxylase and proteins involved in iron management. Five age-matched individuals with no neurologic history served as controls.

RESULTS

There were no histopathologic abnormalities unique to the RLS brains. Tyrosine hydroxylase staining in the major dopaminergic regions appeared normal in the RLS brains. Iron staining and H-ferritin staining was markedly decreased in the RLS substantia nigra. Although H-ferritin was minimally detected in the RLS brain, L-ferritin staining was strong. However, the cells staining for L-ferritin in RLS brains were morphologically distinct from those in the control brains. Transferrin receptor staining on neuromelanin-containing cells was decreased in the RLS brains compared to normal, whereas transferrin staining in these cells was increased.

CONCLUSIONS

RLS may not be rooted in pathologies associated with traditional neurodegenerative processes but may be a functional disorder resulting from impaired iron acquisition by the neuromelanin cells in RLS. The underlying mechanism may be a defect in regulation of the transferrin receptors.

Advances in the management of endobronchial lung malignancies

The effective palliation of endobronchial malignancies often involves the use of multiple modalities including surgery, external beam radiation, chemotherapy, or a variety of interventional bronchoscopic techniques. The authors discuss in detail recent advances in interventional bronchoscopy that enhance local tumor control. An integrated and individualized approach to the use of these complementary modalities can provide rapid palliation and may improve survival in a subset of patients.

Family history study of the restless legs syndrome

BACKGROUND

Although there is a relatively high rate of occurrence of sporadic cases of restless legs syndrome (RLS), the systematic study of family history of RLS in populations of RLS patients has been very limited. The objective of the present study was to determine the risk of RLS for first- and second-degree relatives of a population of primary RLS patients not selected for the number of affected relatives in their families and to obtain an estimate of the degree of genetic involvement in RLS.

METHODS

Consecutively consenting patients from two different sites who met the criteria for RLS completed a worksheet that asked them to indicate their current age, the date of their earliest RLS symptoms, and the names and RLS status of all of their first- and second-degree relatives. Controls with no clinical history of RLS also completed the worksheet.

RESULTS

First- and second-degree relatives of patients with RLS had a significantly greater risk of RLS than the first- (P<0.001) and second-degree relatives (P<0.003) of controls. The risk of RLS was found to be greater for first-degree relatives of early-onset, rather than late-onset, RLS probands (P<0.001).

CONCLUSIONS

This study provides a complete systematic examination of the risk of RLS among relatives of RLS probands and controls using the same assessment methodology. Although the results are consistent with a genetic etiology for RLS, they do not support the presence of one simple, Mendelian-inherited major gene in most RLS families.

Increased CSF hypocretin-1 (orexin-A) in restless legs syndrome

Hypocretin-1 levels were increased in evening CSF samples from subjects with restless legs syndrome, indicating altered hypocretin transmission in this sleep disorder. Increases in CSF hypocretin-1 levels were most striking in patients with early-onset restless legs syndrome.

CSF dopamine, serotonin, and biopterin metabolites in patients with restless legs syndrome

PURPOSE

To evaluate the role of CNS dopaminergic systems in Restless Legs Syndrome (RLS), homovanillic acid (HVA), tetrahydrobiopterin (BH4), and neopterin (NEOP), were assayed in CSF from RLS patients. The serotonin metabolite, 5-hydroxyindoleacetic acid (5-HIAA), was also measured.

METHODS

CSF was taken from 16 RLS patients after 2 weeks off medication and from 14 control subjects. The CSF metabolites were determined using HPLC techniques.

RESULTS

There was no significant difference in HVA or 5-HIAA, but NEOP and BH4 were higher in RLS patients. The RLS group was significantly older than the control group (64.2 +/- 9.2 years vs. 51.4 +/- 6.3 years; P < 0.001). A multiple regression analysis showed a strong correlation between age and 5-HIAA (r = 0.46, P = 0.04) and between age and NEOP (r = 0.61, P < 0.01). To eliminate the potential error created by the age difference between groups, an age-adjusted subgroup of RLS and control subjects were compared. There was still no difference found for HVA; however, 5-HIAA was now significantly lower (P < 0.01) in the RLS subgroup. Age-adjustment eliminated the differences previously found for NEOP, (P = 0.12), but BH4 continued to remain higher in the RLS group (P < 0.01).

CONCLUSION

Differences in CSF HVA concentrations were not found. The changes in 5-HIAA and BH4 are of unclear clinical significance and require further assessment with appropriate age-matched controls.

Restless legs syndrome: a review of clinical and pathophysiologic features

Restless legs syndrome (RLS), although long ignored and still much underdiagnosed, disrupts the life and sleep considerably of those who have it. Recent clinical and basic research provides for better definition and pathophysiologic understanding of the disorder. The body of knowledge about this disorder has been expanding rapidly during the past decade and it has altered our concepts of this disorder. This review of RLS covers history, diagnosis, morbidity of sleep disturbance, relation to periodic limb movements in both sleep and waking, secondary causes, severity assessment methods, phenotypes for possible genetic patterns, epidemiology, pathophysiology, and medical treatment considerations. The emphasis on pathophysiology includes consideration of central nervous system localization, neurotransmitter and other systems involved, and the role of iron metabolism. Studies to date support the authors' recently advanced iron-dopamine model of RLS.

Investigation of preference for nightly triazolam versus placebo in moderate social alcohol drinkers

This study was designed to examine whether the widely prescribed benzodiazepine hypnotic triazolam has reinforcing effects in moderate social alcohol drinkers, without histories of drug abuse or insomnia, in the context of its use as a hypnotic. Eleven healthy adult volunteers who met criteria for 'good sleepers' participated in a 60-session double-blind choice study which was conducted on an outpatient basis with participants sleeping at home. Twenty three-session sampling/choice tests were conducted sequentially to provide 20 evaluations of the reinforcing effects of 0.25 mg/70 kg triazolam versus placebo, ingested orally 30 min before bedtime. Each three-session test consisted of two sampling sessions, in which participants received exposure to each of the two drug conditions in different colored capsules, followed by one choice session, in which participants were asked to choose one of the two colour-coded capsules for self-administration. Four participants exhibited a significant choice of triazolam, three, a significant choice of placebo (i.e. triazolam avoidance), and four, a random (i.e. non-significant) choice between triazolam and placebo. The reasons provided by participants were consistent with their choices and with the expected effects of triazolam versus placebo. Analyses of post-sleep questionnaires indicated that triazolam did not produce a clinically meaningful improvement in sleep. The finding that triazolam functioned as a reinforcer in participants without insomnia suggests that triazolam has reinforcing effects in some individuals for which hypnotic treatment is not clinically indicated, and that health care professionals must continue to assess the risk/benefit ratio of benzodiazepine hypnotic prescription.

MRI measurement of brain iron in patients with restless legs syndrome

Brain iron insufficiency in the restless legs syndrome (RLS) has been suggested by a prior CSF study. Using a special MRI measurement (R2'), the authors assessed regional brain iron concentrations in 10 subjects (five with RLS, five controls). R2' was significantly decreased in the substantia nigra, and somewhat less significantly in the putamen, both in proportion to RLS severity. The results show the potential utility of this MRI measurement, and also indicate that brain iron insufficiency may occur in patients with RLS in some brain regions.

CSF dopamine, serotonin, and biopterin metabolites in patients with restless legs syndrome

PURPOSE

To evaluate the role of CNS dopaminergic systems in Restless Legs Syndrome (RLS), homovanillic acid (HVA), tetrahydrobiopterin (BH4), and neopterin (NEOP), were assayed in CSF from RLS patients. The serotonin metabolite, 5-hydroxyindoleacetic acid (5-HIAA), was also measured.

METHODS

CSF was taken from 16 RLS patients after 2 weeks off medication and from 14 control subjects. The CSF metabolites were determined using HPLC techniques.

RESULTS

There was no significant difference in HVA or 5-HIAA, but NEOP and BH4 were higher in RLS patients. The RLS group was significantly older than the control group (64.2 +/- 9.2 years vs. 51.4 +/- 6.3 years; P < 0.001). A multiple regression analysis showed a strong correlation between age and 5-HIAA (r = 0.46, P = 0.04) and between age and NEOP (r = 0.61, P < 0.01). To eliminate the potential error created by the age difference between groups, an age-adjusted subgroup of RLS and control subjects were compared. There was still no difference found for HVA; however, 5-HIAA was now significantly lower (P < 0.01) in the RLS subgroup. Age-adjustment eliminated the differences previously found for NEOP, (P = 0.12), but BH4 continued to remain higher in the RLS group (P < 0.01).

CONCLUSION

Differences in CSF HVA concentrations were not found. The changes in 5-HIAA and BH4 are of unclear clinical significance and require further assessment with appropriate age-matched controls.

Insight into the pathophysiology of restless legs syndrome

Restless Legs Syndrome (RLS) is a disorder of sensation with a prevalence of around 2-5% of the population. Relevant to understanding the possible pathophysiological mechanism is the fact that RLS is extremely responsive to dopaminergic agents. A second issue is that iron deficiency states may precipitate RLS in as much as 25-30% of people with iron deficiency. Studies looking at basal ganglia dopaminergic function using PET and SPECT techniques have shown a decrease in binding potential for the dopamine receptor and transporter. Similar phenomena occurs in iron-deficient animals. Using MRI techniques and CSF analysis of iron-related protein, studies have suggested a reduction in brain iron concentration occurs in RLS patients. The relevance of CNS iron metabolism to the pathophysiology of RLS is discussed.

Subclinical sensory neuropathy in late-onset restless legs syndrome

OBJECTIVE

To determine the prevalence of different forms of peripheral neuropathy in patients with restless legs syndrome (RLS) and correlate the findings with other clinical characteristics.

BACKGROUND

RLS is characterized by a desire to move the extremities, often associated with paresthesias or dysesthesias, motor restlessness, worsening of symptoms with rest with relief by activity, and worsening of symptoms in the evening or night. The association between RLS and peripheral neuropathy remains controversial. The observation that many patients with small-fiber neuropathy also complain of RLS prompted this prospective case series.

METHODS

Twenty-two consecutive patients with RLS were evaluated for evidence of large-fiber neuropathy (LFN) and small sensory fiber loss (SSFL).

RESULTS

In eight of the 22 (36%) patients, neuropathy was identified. Three patients had pure LFN; two had mixed LFN and SSFL; and three had isolated SSFL. The SSFL group had a later onset of RLS (p < 0.009), reported pain in their feet with RLS more frequently (p < 0.001), and tended to have no family history of RLS (p < 0.078). Patients with LFN did not have similar associations with age at onset, family history status, or presence of pain.

CONCLUSION

The results suggest that two forms of RLS exist: one is triggered by painful dysesthesias associated with SSFL, has later onset, and no family history; and one without involvement of SSF, with an earlier onset age, positive family history for RLS, and no pain. The authors hypothesize that patients with the SSFL subtype of RLS will preferentially respond to neuropathic pain medications.

Near infrared spectrophotometry for the diagnosis of vasculogenic erectile dysfunction

A specialized near infrared spectrophotometry instrument for noninvasive, continuous monitoring of the hemodynamic events of erection in the human penis has been developed. Its potential application for the diagnostic evaluation of erectile dysfunction was investigated. Thirty-eight patients and 18 volunteer subjects underwent penile near infrared spectrophotometry using an optical sensor probe with wavelength selectivity for hemoglobin absorption spectra. Penile blood volume changes and their time courses were measured following intracavernous pharmacostimulation in patients and visual sexual stimulation in volunteers. Spectrophotometric results were compared with results obtained simultaneously using color duplex ultrasonography, strain gauge penile circumference monitoring, penile tonometry, and clinical assessments. Spectrophotometric recordings of penile erection showed measurable blood volume changes consistent with the hemodynamic events of this biological function. Blood volume per cent (BV%) increase correlated with clinical ratings of erection quality (P < 0.001), penile rigidity measurements (P < 0.005), and penile circumference increases (P < 0.0001), and it correlated with mean peak systolic velocity measurements when BV% increase was restricted to values less than 50% (P < 0.001). The time to reach half the maximum blood volume change (BV T1) correlated directly with the time to reach half the maximum penile circumference size increase (P < 0.001), whereas BV T4 correlated inversely with mean resistive index measurements only when BV T(1/2) was restricted to values greater than 120 s (P < 0.05). Spectrophotometric criteria consisting of BV % less than 35% and BV T(1/2) greater than 120 s affirmed the diagnosis of severe erectile impairment with a similar degree of accuracy as standard ultrasonographic criteria (P < 0.002). Penile near infrared spectrophotometry is a safe, inexpensive and simply used biomedical optics technique that provides quantitative measurements of the vascular physiology of penile erection and appears to offer clinical utility in the diagnosis of vasculogenic erectile dysfunction.

Abnormalities in CSF concentrations of ferritin and transferrin in restless legs syndrome

CSF and serum were obtained from 16 patients with idiopathic restless legs syndrome (RLS) and 8 age-matched healthy control subjects. Patients with RLS had lower CSF ferritin levels (1. 11 +/- 0.25 ng/mL versus 3.50 +/- 0.55 ng/mL; p = 0.0002) and higher CSF transferrin levels (26.4 +/- 5.1 mg/L versus 6.71 +/- 1.6 mg/L; p = 0.018) compared with control subjects. There was no difference in serum ferritin and transferrin levels between groups. The presence of reduced ferritin and elevated transferrin levels in CSF is indicative of low brain iron in patients with idiopathic RLS.

Defining the phenotype of the restless legs syndrome (RLS) using age-of-symptom-onset

Objective: RLS varies considerably in both frequency of occurrence in a family and in age of onset of symptoms. Patients whose RLS symptoms start before or at age 45 have many more affected relatives than those whose symptoms start later, suggesting etiological differences. When etiology differs, factors affecting severity may differ. This study compares the effects of current age and serum ferritin on RLS severity for early- and late-onset (over 45) RLS.Design and methods: RLS severity was evaluated using a validated clinical severity scale and sleep efficiency on a standard polysomnogram. Data from 26 consecutive RLS patients (14 early- and 12 late-onset) who met study criteria were analyzed.Results: Age-of-onset groups showed no significant differences in age, gender and RLS symptom severity. Regression analyses showed significant (P<0.05) differences with RLS severity primarily affected by age for early-onset RLS and by serum ferritin for late-onset RLS.Conclusions: The age effect for early-onset RLS indicates a slowly progressive disorder. Thus early-onset RLS appears to occur commonly in families, slowly progress with age and have a limited relation to serum iron status. In contrast, late-onset RLS appears to occur less commonly in families, rapidly progress with age and have a strong relation to serum iron status. Age of symptom onset should be considered to better define the RLS phenotype in future studies.

Sleep, anxiety, and depression in abstinent and drinking alcoholics

A group of alcoholic men were followed-up 8 years after discharge from hospital. The interview included items on sleep, anxiety, and depression. The sample was divided into abstinent and drinking subjects. Sleep data were factor analyzed. Only the Alcohol-Abstinence Sleep Factor significantly correlated with drinking status. The Alcohol-Abstinence Sleep Factor was also the primary correlate of anxiety and depression. Fewer abstinent subjects reported anxiety and depression. Sleep variables, anxiety, and depression are considered as possible markers of relapse in persons treated for alcoholism.

Randomized, double-blind, placebo-controlled trial of pergolide in restless legs syndrome

OBJECTIVE

To assess the efficacy of pergolide in the treatment of restless legs syndrome (RLS).

METHODS

A randomized, double-blind, parallel-treatment evaluation of pergolide versus placebo in patients with RLS was performed. Sixteen patients seen in the Sleep Disorders Center who met the clinical criteria for RLS were enrolled in the study. Treatment was either placebo (n=8) or pergolide (n=8), which was on a self-adjusted schedule that ranged from 0.05 to 0.65 mg/day. Outcome variables included the patient's rating of symptom improvement, duration of RLS symptoms throughout the day, and objective sleep assessments from an all-night polysomnogram (percent sleep efficiency and periodic leg movements). Baseline was assessed for 2 days before starting treatment. Dose adjustments were made over the first 14 days and were then held constant for 5 days, with repeat assessment for treatment effects on the last 2 days of treatment (days 17 and 18).

RESULTS

As a group, pergolide recipients showed significant improvement clinically and statistically in all outcome measures when compared with baseline or with placebo treatment. On the other hand, placebo treatment led to no significant improvements in any outcome measures.

CONCLUSIONS

Pergolide treatment significantly improved clinical symptoms and sleep efficiency, and reduced periodic limb movements of sleep in patients with RLS.

Iron and the restless legs syndrome

STUDY OBJECTIVES

Using blinded procedures, determine the relation between serum ferritin levels and severity of subjective and objective symptoms of the restless legs syndrome (RLS) for a representative patient sample covering the entire adult age range.

DESIGN

All patient records from the past 4 years were retrospectively reviewed to obtain data from all cases with RLS. All patients were included who had ferritin levels obtained at about the same time as a polysomnogram (PSG), met diagnostic criteria for RLS, and were not on iron or medications that would reduce the RLS symptoms at the time of the PSG.

SETTING

Sleep Disorders Center.

PATIENTS

27 (18 females, 9 males), aged 29-81 years.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

Measurements included clinical ratings of RLS severity and PSG measures of sleep efficiency and periodic limb movements (PLMS) in sleep with and without arousal. Lower ferritin correlated significantly to greater RLS severity and decreased sleep efficiency. All but one patient with severe RLS had ferritin levels < or = 50 mcg/l. Patients with lower ferritin (< or = 50 mcg/l) also showed significantly more PLMS with arousal than did those with higher ferritin, but the PLMS/hour was not significantly related to ferritin. This last finding may be due to inclusion of two 'outliers' or because of severely disturbed sleep of the more severe RLS patients.

CONCLUSIONS

These data are consistent with those from a prior unblinded study and suggest that RLS patients will have fewer symptoms if they have ferritin levels greater than 50 mcg/l.