Understanding the Associations of Prenatal Androgen Exposure on Sleep Physiology, Circadian Proteins, Anthropometric Parameters, Hormonal Factors, Quality of Life, and Sex Among Healthy Young Adults: Protocol for an International, Multicenter Study.

BACKGROUND: The ratio of the second finger length to the fourth finger length (2D:4D ratio) is considered to be negatively correlated with prenatal androgen exposure (PAE) and positively correlated with prenatal estrogen. Coincidentally, various brain regions are sensitive to PAE, and their functions in adults may be influenced by the prenatal actions of sex hormones. OBJECTIVE: This study aims to assess the relationship between PAE (indicated by the 2D:4D ratio) and various physiological (sex hormone levels and sleep-wake parameters), psychological (mental health), and sexual parameters in healthy young adults. METHODS: This study consists of two phases. In phase 1, we will conduct a survey-based study and anthropometric assessments (including 2D:4D ratio and BMI) in healthy young adults. Using validated questionnaires, we will collect self-reported data on sleep quality, sexual function, sleep chronotype, anxiety, and depressive symptoms. In phase 2, a subsample of phase 1 will undergo polysomnography and physiological and genetic assessments. Sleep architecture data will be obtained using portable polysomnography. The levels of testosterone, estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, prolactin, melatonin, and circadian regulatory proteins (circadian locomotor output cycles kaput [CLOCK], timeless [TIM], and period [PER]) and the expression levels of some miRNAs will be measured using blood samples. The rest and activity cycle will be monitored using actigraphy for a 7-day period. RESULTS: In Poland, 720 participants were recruited for phase 1. Among these, 140 completed anthropometric measurements. In addition, 25 participants joined and completed phase 2 data collection. Recruitment from other sites will follow. CONCLUSIONS: Findings from our study may help to better understand the plausible role of PAE in sleep physiology, mental health, and sexual quality of life in young adults. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/29199.

Morning Headache as an Obstructive Sleep Apnea-Related Symptom among Sleep Clinic Patients-A Cross-Section Analysis.

Morning headache is considered to be a symptom of obstructive sleep apnea syndrome (OSAS). Despite not being as common as excessive daytime sleepiness or unrefreshing sleep, it can similarly impair everyday activities. The aim of the present study was to evaluate the prevalence of and factors associated with morning headaches (MH) among patients referred for polysomnography due to suspected OSAS. This is a retrospective study on 1131 patients who underwent polysomnography between 2013 and 2015. Morning headaches (MH) were reported in 29% of them. In a logistic regression model, a rise in the n probability of MH was associated with female sex (odds ratio, OR, 1.38, 95% confidence interval, CI, 1.08-1.75), history of hypertension (OR 1.25, 95% CI 1.06-1.46), complaint on unrefreshing sleep (OR 1.42, 95% CI 1.19-1.70), choking at night (OR 1.25, 95% CI 1.05-1.49), and fall in total sleep time (OR 0.872 per each hour, 95% CI 0.76-0.99). The risk between MH and apnea-hypopnea index, blood oxygen saturation parameters or arousal index was found to be statistically insignificant. There is a lack of evidence that MH is associated with the severity of OSAS or nocturnal hypoxemia.

High Negative Predictive Value of Normal Body Mass Index for Obstructive Sleep Apnea in the Lateral Sleeping Position.

STUDY OBJECTIVES: Obesity is a major risk factor for obstructive sleep apnea (OSA). Patients who are not obese and who have OSA usually present with a low apnea-hypopnea index (AHI) in the lateral sleeping position. Hence, sleep-disordered breathing (SDB) seems more dependent on body mass index (BMI) in the lateral sleeping position than the supine sleep position. This makes obesity a better predictor of SDB in the lateral sleeping position. The objective of this study was to find a negative predictive value of normal BMI for SDB in relation to sleep positions, thus defining a group of patients who could be treated by positional intervention, and prioritizing the use of polysomnography diagnostics. METHODS: This study comprises a retrospective and prospective part run on groups of 1,181 and 821 consecutive patients, respectively. All had been referred to the university-based sleep laboratory because of suspected OSA and underwent polysomnography. RESULTS: In the retrospective study, areas under the receiver operating characteristic curves for normal BMI at AHI ≥ 5 and AHI ≥ 15 events/h were found to be larger in the lateral sleeping positing than supine: 0.79 versus 0.69 and 0.80 versus 0.68, respectively (P < .05). Comparable results were obtained in the prospective study. For normal BMI, the negative predictive value for AHI < 15 events/h in the lateral sleep position was 97.5% and 97.1% in the retrospective and prospective study, respectively. CONCLUSIONS: Normal BMI offers a high negative predictive value for moderate or severe OSA in the lateral sleeping position.