Israel Medical Association Journal

Pathological gambling is classified in the DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders) and in the ICD-10 (International Classification of Disease) as an impulse control disorder. The association between impulsivity and pathological gambling remains a matter of debate: some researchers find high levels of impulsivity within pathological gamblers, others report no difference compared to controls, and yet others even suggest that it is lower. In this review we examine the relationship between pathological gambling and impulsivity assessed by various neurocognitive tests. These tests – the Stroop task, the Stop Signal Task, the Matching Familiar Figures Task, the Iowa Gambling Task, the Wisconsin Card Sorting Test, the Tower of London test, and the Continuous Performance Test – demonstrated less impulsivity in gambling behavior. The differences in performance between pathological gamblers and healthy controls on the neurocognitive tasks could be due to addictive behavior features rather than impulsive behavior.

Background: The Pittsburgh Sleep Quality Index is a standardized self-administered questionnaire for the assessment of subjective sleep quality. It has been translated into several languages and is widely used in clinical research studies.

Objectives: To assess the reliability and validity of the Pittsburgh Sleep Quality Index Hebrew translation in a sleep clinic sample and in comparison with the Technion Mini Sleep Questionnaire.

Methods: The PSQI[1] was translated into Hebrew based on standard guidelines. The final Hebrew version (PSQI-H) was administered to 450 patients from two sleep clinics and to 61 healthy adults from the community as a non-clinical control sample. The MSQ[2] was administered to 130 patients in one sleep clinic.

Results: For the PSQI-H[3], Cronbach's-alpha scores for sleep clinic and non-clinical samples were 0.70 and 0.52 respectively and 0.72 combined. Clinical sample scores were significantly higher than the non-clinical group, indicating lower sleep quality for the former. Significant correlations were found between the MSQ subscores and PSQI-H component scores for common underlying constructs.

Conclusions: The PSQI-H differentiated between clinical and non-clinical samples and showed adequate reliability and good validity. It may be used as a standardized tool for the assessment of subjective sleep quality in clinical research studies conducted in the Hebrew-speaking population.

Background: Phototherapy is considered the standard of care for neonatal jaundice. However, its short term cardiorespiratory effects have not been studied thoroughly.

Objectives: To assess the cardiorespiratory effect of phototherapy during sleep in term infants with physiologic jaundice.

Methods: We performed two polysomnography studies during 3 hours sleep in 10 healthy term infants with physiologic jaundice; each infant served as his/her own control. The first study was performed just prior to phototherapy and the second study during phototherapy 24 hours later. Heart and respiratory rates, type and duration of apneas, and arterial oxygen saturation were analyzed during active and quiet sleep.

Results: Term infants (gestational age 38.6 ± 1.4 weeks, birth weight 3.2 ± 0.5 kg) underwent the two polysomnography studies within a short time interval and had a comparable bilrubin level (3.6 ± 0.8 and 4.5 ± 0.8 days; 14.5 ± 1.4 and 13.8 ± 2.1 mg/dl, P = NS, respectively). There was no difference in sleeping time or the fraction of active and quiet sleep before or during phototherapy. During active sleep under phototherapy there was a significant decrease in respiratory rate and increase in heart rate (54.3 ± 10.3 vs. 49.1 ± 10.8 breaths/minute, and 125.9 ± 11.7 vs. 129.7 ± 15.3 beats/minute, respectively, P < 0.05), as well as a decrease in respiratory effort in response to apnea. These effects were not found during quiet sleep. Phototherapy had no significant effect on oxygen saturation, apnea rate or periodic breathing in either sleep state. No clinical significant apnea or bradycardia occurred.

Conclusions: Phototherapy affected the cardiorespiratory activity during active sleep but not during quiet sleep in term infants with physiologic jaundice. These effects do not seem to have clinical significance in "real-life" conditions.

Background: Continuous positive airway pressure is the treatment of choice for patients with obstructive sleep apnea syndrome.

Objective: To determine the factors influencing treatment initiation with a CPAP[1] device in a healthcare system in which co-payment is required.

Methods: A total of 400 adult patients with OSAS[2] who required CPAP therapy completed questionnaires at three different stages of the diagnostic and therapeutic process: CPAP titration study (stage 1), patient adaptation trial (stage 2), and purchase of a CPAP device (stage 3). Logistic regression was used to analyze the variables influencing CPAP use at the different stages of the diagnostic and therapeutic processes.

Results: Only 32% of the patients who underwent CPAP titration study purchased a CPAP device. The number of subjects who purchased a CPAP device increased gradually as monthly income increased, 28% vs. 62% in the “very low” and “very high” income levels respectively. Reporting for the titration increased in patients with excessive daytime sleepiness and an Epworth Sleepiness Scale score above 9 (odds ratio = 1.9, P = 0.015). Higher socioeconomic status increased reporting to stage 2 (OR[3] = 1.23, P = 0.03) and CPAP purchase (stage 3, OR = 1.35, P = 0.002). Excessive daytime sleepiness increased reporting to stage 2 (OR = 2.28, P = 0.006). Respiratory disturbance index above 35 increased CPAP purchasing (OR = 2.01, P = 0.022). Support from the bed partner, referring physician and sleep laboratory team increased CPAP purchasing.

Conclusions: A supportive environment for a patient with OSAS requiring CPAP is crucial to increase initiation of CPAP treatment. Minimizing cost sharing for the CPAP device will reduce inequality and may increase CPAP treatment initiation.

Obstructive sleep apnea syndrome is a major public health hazard affecting 2–4% of the adult population; only 10% of these patients are recognized by healthcare providers. In the last decade the number of referrals for polysomnography increased threefold in Israel, compared to 12-fold worldwide, and is expected to increase even more in the coming years. This constant demand for PSG[1] studies is beyond the current capacity of sleep laboratories, thus preventing diagnosis for most patients with suspected OSAS[2]. In the current review, we examine problems facing decision-makers on how to treat the increasing flood of patients presenting with symptoms suggestive of sleep-disordered breathing. We evaluate the cost-effectiveness of current technologies for OSA diagnosis, i.e., laboratory versus at-home technologies. We conclude that no current alternative exists to the use of PSG for OSA diagnosis. When at-home technologies are suggested for OSAS diagnosis, data should be provided on factors influencing its cost-effectiveness, e.g., accuracy rates of diagnosis, relative cost of human resources, and case-mix of patients tested. Since PSG remains the gold standard for diagnosis of OSAS, in Israel resources should be allocated to increasing the volume of beds for PSG studies in order to increase access to diagnosis and treatment, which in turn provides better quality of life, saves scarce resources of the healthcare system, prevents unnecessary accidents and increases workers’ productivity.

Background: Prone sleeping has been recognized as a risk factor for sudden infant death syndrome. Ten years ago, non-prone sleeping was recommended in many countries around the world including Israel. The rate of infants sleeping prone and the rate of parents' adherence with the recommendations have not been studied.

Objectives: To study infants' sleep position and parents’ adherence to recommendations, and to identify risk factors for prone sleeping following the campaign to prevent prone sleeping in the Israeli population.

Methods: We conducted a longitudinal telephone survey with the parents of 608 randomly selected 2 month old infants, repeated at 4 and 6 months.

Results: Non-prone sleeping decreased from 75% to 67% and 63% at 2, 4 and 6 months respectively. There was a significant relationship between prone positioning and the use of a home apnea monitor at 2 months (P = 0.038, odds ratio 1.37, 95% confidence interval 0.94–2.15). Other risk factors for prone sleeping were the level of religious practice, with ultra-Orthodox Jews having the highest prevalence (2 months: OR[1] 2.78, 95% CI[2] 1.75–4.55) and higher parity – especially in families with more than five children (P = 0.041).

Conclusions: The prone sleeping position is relatively high in Israel. Groups at high risk were closely associated with the level of religiousness and parity. Efforts to promote supine sleeping should be directed towards identifiable groups.

The novel neuropeptides hypocretin/orexin have recently been located on the lateral hypothalamus cells. This system has been linked to the regulation of both feeding and sleep, and recent studies have found an association between a defect in these neuropeptides and narcolepsy. We conducted a MED­LINE review of all the articles published since the discovery of hypocretin/orexin peptides, narrowing the field to the relation­ship between these neuropeptides and sleep. The finding of a deletion in the transcription of the hypocretin receptor 2 gene in narcoleptic Doberman pinschers and the development of a knockout of the hypocretin gene in mice pointed to the relevance of this system in the sleep-wake cycle. We provide further evidence of the role of the hypocretin/orexin system in narcolepsy and in sleep regulation and present an integrative model of the pathophysiology of narcolepsy. The discovery of the link between these peptides and narcolepsy opens new avenues to both the understanding of sleep mechanisms and therapeutic implications for sleep disorders.