Pseudo-pheochromocytoma due to obstructive sleep apnea: a case report

SUMMARY

Obstructive sleep apnea (OSA) is a condition of intermittent nocturnal upper airway obstruction. OSA increases sympathetic drive which may result in clinical and biochemical features suggestive of pheochromocytoma. We present the case of a 65-year-old male with a 2.9-cm left adrenal incidentaloma on CT, hypertension, symptoms of headache, anxiety and diaphoresis, and persistently elevated 24-h urine norepinephrine (initially 818 nmol/day (89-470)) and normetanephrine (initially 11.2 µmol/day (0.6-2.7)). He was started on prazosin and underwent left adrenalectomy. Pathology revealed an adrenal corticoadenoma with no evidence of pheochromocytoma. Over the next 2 years, urine norepinephrine and normetanephrine remained significantly elevated with no MIBG avid disease. Years later, he was diagnosed with severe OSA and treated with continuous positive airway pressure. Urine testing done once OSA was well controlled revealed complete normalization of urine norepinephrine and normetanephrine with substantial symptom improvement. It was concluded that the patient never had a pheochromocytoma but rather an adrenal adenoma with biochemistry and symptoms suggestive of pheochromocytoma due to untreated severe OSA. Pseudo-pheochromocytoma is a rare presentation of OSA and should be considered on the differential of elevated urine catecholamines and metanephrines in the right clinical setting.

LEARNING POINTS

Obstructive sleep apnea (OSA) is a common condition among adults. OSA may rarely present as pseudo-pheochromocytoma with symptoms of pallor, palpitations, perspiration, headache, or anxiety. OSA should be considered on the differential of elevated urine catecholamines and metanephrines, especially in patients with negative metaiodobenzylguanidine (MIBG) scan results.

Fatigue in Aviation: Safety Risks, Preventive Strategies and Pharmacological Interventions

Fatigue poses an important safety risk to civil and military aviation. In addition to decreasing performance in-flight (chronic) fatigue has negative long-term health effects. Possible causes of fatigue include sleep loss, extended time awake, circadian phase irregularities and work load. Despite regulations limiting flight time and enabling optimal rostering, fatigue cannot be prevented completely. Especially in military operations, where limits may be extended due to operational necessities, it is impossible to rely solely on regulations to prevent fatigue. Fatigue management, consisting of preventive strategies and operational countermeasures, such as pre-flight naps and pharmaceuticals that either promote adequate sleep (hypnotics or chronobiotics) or enhance performance (stimulants), may be required to mitigate fatigue in challenging (military) aviation operations. This review describes the pathophysiology, epidemiology and effects of fatigue and its impact on aviation, as well as several aspects of fatigue management and recommendations for future research in this field.

Multi-Scale Permutation Entropy: A Potential Measure for the Impact of Sleep Medication on Brain Dynamics of Patients with Insomnia

Insomnia is a common sleep disorder that is closely associated with the occurrence and deterioration of cardiovascular disease, depression and other diseases. The evaluation of pharmacological treatments for insomnia brings significant clinical implications. In this study, a total of 20 patients with mild insomnia and 75 healthy subjects as controls (HC) were included to explore alterations of electroencephalogram (EEG) complexity associated with insomnia and its pharmacological treatment by using multi-scale permutation entropy (MPE). All participants were recorded for two nights of polysomnography (PSG). The patients with mild insomnia received a placebo on the first night (Placebo) and temazepam on the second night (Temazepam), while the HCs had no sleep-related medication intake for either night. EEG recordings from each night were extracted and analyzed using MPE. The results showed that MPE decreased significantly from pre-lights-off to the period during sleep transition and then to the period after sleep onset, and also during the deepening of sleep stage in the HC group. Furthermore, results from the insomnia subjects showed that MPE values were significantly lower for the Temazepam night compared to MPE values for the Placebo night. Moreover, MPE values for the Temazepam night showed no correlation with age or gender. Our results indicated that EEG complexity, measured by MPE, may be utilized as an alternative approach to measure the impact of sleep medication on brain dynamics.

Assessing the validity of eyelid parameters to detect impairment due to benzodiazepines

OBJECTIVE

Benzodiazepines impair driving ability and psychomotor function. Eyelid parameters accurately reflect drowsiness; however, the effects of benzodiazepines on these measures have not been extensively studied. The aim of this study was to investigate the effect of benzodiazepines on eyelid parameters and evaluate their accuracy for detecting psychomotor impairment.

METHODS

Eyelid parameters were recorded during a psychomotor vigilance task (PVT) and driving simulation over 2 days, baseline, and after 20-mg oral temazepam. The utility of eyelid parameters for detecting PVT lapses was evaluated using receiver operating characteristic curves, and cut-off levels indicating impairment (≥1 and ≥2 PVT lapses per min) were identified. The accuracy of these cut-off levels for detecting driving simulator crashes was then examined.

RESULTS

PVT and driving simulator performance was significantly impaired following benzodiazepine administration (p < .05). Average eyelid closure duration (inter-event duration) was a reliable indicator of PVT lapses (area under the curve [AUC] of 0.87-0.90). The cut-off value of eyelid closure duration derived from PVT AUC was able to predict driving simulator crashes with moderately high sensitivity and specificity (76.23% and 75.00%).

CONCLUSIONS

Eyelid parameters were affected by benzodiazepines and accurately detected the psychomotor impairment. In particular, eyelid closure duration is a promising real-time indicator of benzodiazepine impairment.

Melatonin, temazepam and placebo in hospitalised older patients with sleeping problems (MATCH): a study protocol of randomised controlled trial

INTRODUCTION

Hospitalised older patients frequently suffer from inadequate sleep, which can lead to patient distress and delayed recovery from acute illness or surgical procedure. Currently, no evidence-based treatments exist for sleeping problems in hospitalised older patients. Benzodiazepines, such as temazepam, are regularly prescribed by physicians, although they have serious side effects; for older patients in particular. Melatonin is proposed as a safe alternative for sleeping problems in hospitalised older patients, but the efficacy of melatonin is unclear in this population. Therefore, the aim of this study is to investigate the effects of melatonin and temazepam compared with placebo on sleep quality among hospitalised older patients with sleeping problems.

METHODS AND ANALYSIS

This study is a multicentre, randomised, placebo-controlled trial. A total of 663 patients will be randomised in a 1:1:1 fashion to receive either melatonin (n=221), temazepam (n=221) or placebo (n=221). The study population consists of hospitalised patients aged 60 years and older, with new or aggravated sleeping problems for which an intervention is needed. The primary outcome is sleep quality measured with the Leeds Sleep Evaluation Questionnaire (LSEQ). Secondary outcomes include sleep parameters measured with actigraphy and medication-related adverse effects.

ETHICS AND DISSEMINATION

This study was approved by the Medical Ethics Committee of the Academic Medical Centre Amsterdam, (No 2015_302). Study findings will be disseminated through presentations at professional and scientific conferences and publications in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NTR6908; Pre-results.

Dispensing Patterns of Anxiolytics and Sedative-Hypnotics: A Feasibility Study Comparing Datasets from a Developed and a Developing Country (Australia and South Africa)

BACKGROUND

Dispensing patterns reflect drug usage trends. Benzodiazepines are known as drugs with potential for misuse, and frequent dispensing may be a surrogate marker of misuse.

OBJECTIVE

The primary aim of this study was to obtain a comparative snapshot of anxiolytic and sedative-hypnotic dispensing in a developing country and a developed country, to determine whether further research about benzodiazepines is warranted.

METHOD

A cross-national, cross-sectional retrospective drug utilisation study was conducted on benzodiazepines and z-drugs. The South African database was obtained from a national medical insurance administrator and the Australian data were de-identified and extracted from pharmacies in the city of Brisbane in Queensland.

RESULTS

Diazepam was the most frequently dispensed anxiolytic in the Australian dataset (26.4%; n=1057/4010) while in the South African data, diazepam dispensing (17.2%; n=11597/67354) was superseded by alprazolam (17.8%; n=12009/67354) and followed by bromazepam (13.6%; n=9146/67354). The most frequently dispensed hypnotic in the South African data was zolpidem which accounted for 18.7% of records (n=12603/67354), while in the Australian data it was temazepam (24.9%; n=998/4010). Zolpidem was dispensed more frequently than zopiclone in both datasets.

CONCLUSION

In South Africa there was relatively frequent use of alprazolam, bromazepam and zolpidem while in the Australian data diazepam, oxazepam and temazepam were most frequently dispensed. The use of alprazolam, identified as a drug of abuse in Australia, warrants further research in South Africa. The indicator described in this paper permitted a (qualitative) cross-sectional comparison of anxiolytics and sedative-hypnotics between a developed and a developing country (Australia and South Africa).

Randomised clinical trial of the effects of prolonged-release melatonin, temazepam and zolpidem on slow-wave activity during sleep in healthy people

Current pharmacological treatments for insomnia include benzodiazepine and non-benzodiazepine hypnotics targeting γ-aminobutyric acid (GABA)A receptors, as well as agonists of the melatonin receptors MT1 and MT2. Melatonin, temazepam and zolpidem are thought to exert their effect through different mechanisms of action, but whether this leads to differential effects on electroencephalogram (EEG) power spectra during sleep in middle-aged people is currently not known. To establish whether the effects of prolonged-release melatonin (2 mg) on the nocturnal sleep EEG are different to those of temazepam (20 mg) and zolpidem (10 mg). Sixteen healthy men and women aged 55-64 years participated in a double-blind, placebo-controlled, four-way cross-over trial. Nocturnal sleep was assessed with polysomnography and spectral analysis of the EEG. The effects of single oral doses of prolonged-release melatonin, temazepam and zolpidem on EEG slow-wave activity (SWA, 0.75-4.5 Hz) and other frequencies during nocturnal non-rapid eye movement (NREM) sleep were compared. In an entire night analysis prolonged-release melatonin did not affect SWA, whereas temazepam and zolpidem significantly reduced SWA compared with placebo. Temazepam significantly reduced SWA compared with prolonged-release melatonin. Prolonged-release melatonin only reduced SWA during the first third of the night compared with placebo. These data show that the effects of prolonged-release melatonin on the nocturnal sleep EEG are minor and are different from those of temazepam and zolpidem; this is likely due to the different mechanisms of action of the medications.

Melatonin for sedative withdrawal in older patients with primary insomnia: a randomized double-blind placebo-controlled trial

AIM

We compared the efficacy of melatonin and placebo as adjuvants in the withdrawal of patients from long term temazepam, zopiclone or zolpidem (here 'BZD') use.

METHODS

A double-blind, placebo-controlled, randomized trial was conducted in a primary health care outpatient clinic. Ninety-two men or women (≥55 years) with primary insomnia and chronic BZD use received controlled release melatonin 2 mg (CRM) (n = 46) or placebo (n = 46) during the 1 month withdrawal from BZDs. Psychosocial support was provided. Follow-up continued for up to 6 months. Successful BZD withdrawal by the end of 1 month was confirmed by BZD plasma determinations, while reduction in BZD use and abstinence continuing for 6 months were noted.

RESULTS

There were two drop-outs on CRM and one on placebo. After a 1 month withdrawal, 31 participants (67%; 95% CI 54, 81) on CRM and 39 (85%; 74, 95) on placebo had withdrawn completely (intention-to-treat analysis between groups, P = 0.051; per protocol P = 0.043). Reduction in BZD use was similar or even more rare in the CRM than in the placebo group (P = 0.052 per protocol). After 6 months, 14 participants in the CRM group and 20 in the placebo group remained non-users of BZD (NS between groups). BZD doses were higher in the CRM than in the placebo group at the end of the 6 month follow-up (P = 0.025). Withdrawal symptoms did not differ between the groups.

CONCLUSIONS

Gradual dose reduction of BZDs combined with CRM or placebo, and psychosocial support produced high short term and moderate long term BZD abstinence. CRM showed no withdrawal benefit compared with placebo.

Pharmacological interventions for preventing post-traumatic stress disorder (PTSD)

BACKGROUND

Post-traumatic stress disorder (PTSD) is a debilitating disorder which, after a sufficient delay, may be diagnosed amongst individuals who respond with intense fear, helplessness or horror to traumatic events. There is some evidence that the use of pharmacological interventions immediately after exposure to trauma may reduce the risk of developing of PTSD.

OBJECTIVES

To assess the effects of pharmacological interventions for the prevention of PTSD in adults following exposure to a traumatic event.

SEARCH METHODS

We searched the Cochrane Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR-Studies and CCDANCTR-References) (to 14 February 2014). This register contains relevant reports of randomised controlled trials from the following bibliographic databases: CENTRAL (all years); EMBASE (1974 to date); MEDLINE (1950 to date) and PsycINFO (1967 to date). We identified unpublished trials by searching the National Institute of Health (NIH) Reporter, the metaRegister of Controlled Trials database (mRCT) and the WHO International Clinical Trials Registry Platform (to December 2013). We scanned the reference lists of articles for additional studies. We placed no constraints on language and setting.

SELECTION CRITERIA

We restricted studies to randomised controlled trials (RCTs) of pharmacological interventions compared with placebo for the prevention of PTSD in adults.

DATA COLLECTION AND ANALYSIS

Two authors (TA and JI) independently assessed trials for eligibility and inclusion based on the review selection criteria. We independently extracted sample, methodological, outcome and 'Risk of bias' data, as well as the number of side effects, from each trial and entered these into a customised data extraction form. We contacted investigators for missing information. We calculated summary statistics for continuous and dichotomous variables (if provided). We did not undertake subgroup analyses due to the small number of included studies.

MAIN RESULTS

We included nine short-term RCTs (duration 12 weeks or less) in the analysis (345 participants; age range 18 to 76 years). Participants were exposed to a variety of traumas, ranging from assault, traffic accidents and work accidents to cardiac surgery and septic shock. Seven studies were conducted at single centres. The seven RCTs included four hydrocortisone studies, three propranolol studies (of which one study had a third arm investigating gabapentin), and single trials of escitalopram and temazepam. Outcome assessment measures included the Clinician-Administered PTSD Scale (CAPS), the 36-Item Short-Form Health Survey (SF-36) and the Center for Epidemiological Studies - Depression Scale (CES-D).In four trials with 165 participants there was moderate quality evidence for the efficacy of hydrocortisone in preventing the onset of PTSD (risk ratio (RR) 0.17; 95% confidence interval (CI) 0.05 to 0.56; P value = 0.004), indicating that between seven and 13 patients would need to be treated with this agent in order to prevent the onset of PTSD in one patient. There was low quality evidence for preventing the onset of PTSD in three trials with 118 participants treated with propranolol (RR 0.62; 95% CI 0.24 to 1.59; P value = 0.32). Drop-outs due to treatment-emergent side effects, where reported, were low for all of the agents tested. Three of the four RCTs of hydrocortisone reported that medication was more effective than placebo in reducing PTSD symptoms after a median of 4.5 months after the event. None of the single trials of escitalopram, temazepam and gabapentin demonstrated evidence that medication was superior to placebo in preventing the onset of PTSD.Seven of the included RCTs were at a high risk of bias. Differential drop-outs between groups undermined the results of three studies, while one study failed to describe how the allocation of medication was concealed. Other forms of bias that might have influenced study results included possible confounding through group differences in concurrent medication and termination of the study based on treatment response.

AUTHORS' CONCLUSIONS

There is moderate quality evidence for the efficacy of hydrocortisone for the prevention of PTSD development in adults. We found no evidence to support the efficacy of propranolol, escitalopram, temazepam and gabapentin in preventing PTSD onset. The findings, however, are based on a few small studies with multiple limitations. Further research is necessary in order to determine the efficacy of pharmacotherapy in preventing PTSD and to identify potential moderators of treatment effect.

Nocturnal temazepam in the treatment of narcolepsy

Narcolepsy is characterized by fragmented nighttime sleep and frequent arousals. One treatment approach to improve daytime symptoms is to consolidate nighttime sleep through decreasing arousals. Sodium oxybate is the first FDA-approved medication that follows this approach. Benzodiazepines are known to also decrease arousals at night and have been proposed to help with sleep fragmentation. In one report, clonazepam was shown to improve cataplexy in 10 of 14 patients with narcolepsy although no improvement in daytime sleepiness was reported. The purpose of this case review was to share our experience of nocturnal temazepam on daytime sleepiness in patients with narcolepsy as measured by the Epworth Sleepiness Scale (ESS).

Mass Spectra and Cross-Contribution of Ion Intensity Between Drug Analytes and Their Isotopically Labelled Analogs - Benzodiazepines and Their Derivatives

With GC-MS as the preferred method and isotopically labeled analogs (ILAs) of the analytes as the internal standards (ISs) of choice for quantitative determination of drugs/metabolites in biological specimens, one important aspect associated with chemical derivatization (CD) is that the CD products derived from the analyte and the selected IS must generate ions suitable for designating the analyte and the IS. These ions must not have significant cross-contribution (CC), i.e., ISs' contribution to the intensities of the ions designating the analytes, and vice versa. With this in mind, the authors have reviewed literature and information provided by manufacturers, searching for suitable CD reagents, CD methods, and ILAs of the analytes related to the following 18 benzodiazepines: oxazepam, diazepam, nordiazepam, nitrazepam, temazepam, clonazepam, 7-aminoclonazepam, prazepam, lorazepam, flunitrazepam, 7-aminoflunitrazepam, N-desalkylflurazepam, N-desmethylflunitrazepam, 2-hydroxyethylflurazepam, estazolam, alprazolam, α-hydroxyalprazolam, and α-hydroxytriazolam. These analytes and ILAs were derivatized with various derivatization groups, followed by GC-MS analysis. The resulting mass spectrometric data are systematically presented in two forms: (a) full-scan mass spectra; and (b) CC data of ion-pairs with potential for designating the analytes and their respective ILAs (candidates of ISs in quantitative analytical protocols). Many of these full-scan mass spectra are not yet available in the literature and should be of reference value to laboratories engaged in the analysis of these drugs/metabolites. Full-scan MS data were further used to select ion-pairs with potential for designating the analytes and ISs in quantitative analysis protocols. The CC data of these ion-pairs were evaluated using data collected in selected ion monitoring mode and systematically tabulated, making the data readily available for analysts searching for this important analytical parameter.

Gastric decontamination performed 5 min after the ingestion of temazepam, verapamil and moclobemide: charcoal is superior to lavage

AIMS

The aim was to study the efficacy of gastric lavage and activated charcoal in preventing the absorption of temazepam, verapamil and moclobemide when gastric decontamination was performed immediately after ingestion of the drugs.

METHODS

Nine healthy volunteers took part in a randomized cross-over study with three phases. The subjects were administered single oral doses of 10 mg temazepam, 80 mg verapamil and 150 mg moclobemide. Five minutes later, they were assigned to one of the following treatments: 200 ml water (control), 25 g activated charcoal as a suspension in 200 ml water or gastric lavage. Plasma concentrations and the cumulative excretion into urine of the three drugs were determined up to 24 h.

RESULTS

The mean AUC(0,24 h) of temazepam, verapamil and moclobemide was reduced by 95.2% (P < 0.01), 92.8% (P < 0.01) and 99. 7% (P < 0.01), respectively, by activated charcoal compared with control. Gastric lavage did not reduce significantly the AUC(0,24 h) of these drugs. The 24 h cumulative excretion of temazepam, verapamil and moclobemide into urine was reduced significantly (P < 0.05) by charcoal but not by gastric lavage. Charcoal reduced the AUC(0,24 h), Cmax and urinary excretion of all three drugs significantly more than lavage.

CONCLUSIONS

Activated charcoal is very effective and gastric lavage can be rather ineffective in preventing the absorption of temazepam, verapamil and moclobemide when the treatment is given very rapidly after ingestion of the drugs, before tablet disintegration has occurred.