الفهرس 
Sleep physiologyOnly 14 pages are availabe for public view
 |  | from | 129 |  |  |
| | | from | 129 | | |
Abstract
Obstructive sleep apnea (OSA), also referred to as obstructive
sleep apnea-hypopnea syndrome is a sleep disorder that involves
cessation or significant decrease in airflow in the presence of
breathing effort. It is characterized by repetitive partial or complete
obstruction of the upper airway during sleep that results in disruptions
of normal sleep architecture and intermittent nocturnal hypoxia.
OSA is prevalent in both adults and children in modern society.
The estimated prevalence has been 2% for women and 4% for men.
Definite risk factors for OSA include obesity and craniofacial or upper
airway soft tissue abnormalities. Potential risk factors include
heredity, smoking, and nasal congestion.
Obesity is the best documented risk factor for OSA. The
prevalence of OSA progressively increases as body mass index and
associated markers (e.g., neck circumference, waist-to-hip ratio)
increase. A centripetal pattern of obesity with fat preferentially
distributed to the abdominal viscera, upper body and neck is more
closely linked to OSA than a peripheral pattern of obesity.
Obstructive sleep apnea is associated with clinical
complications such as daytime somnolence, hypertension, ischemic
heart disease, and increased risk of stroke. The mechanisms resulting
in these complications include recurrent intermittent hypoxemia and
increased sympathetic activation, primarily at the termination of
apneic events.
In men, testes have two functions: production of testosterone,
which is the predominant circulating androgen by the Leydig cells and
spermatogenesis which takes place within the seminiferous tubules.
Summary
87
Male hypogonadism refers to impairment of one or both of
these functions. It may arise from testicular disease (primary
hypogonadism) where the testes are primarily affected and thus
concentrations of gonadotropins are raised (hypergonadotropic
hypogonadism) or dysfunction of the hypothalamic-pituitary unit
(secondary hypogonadism) and thus concentrations of gonadotropins
are lowered (hypogonadotropic hypogonadism).
Recent literature has shown that OSA is associated with the
development of male hypogonadism. Several studies have confirmed a
strong relationship between OSA and low testosterone.
Both the quantity and quality of sleep affect testosterone levels.
Patients with OSA have less REM sleep, reduced deep sleep time,
increased nighttime awakenings, sleep fragmentation, reduced sleep
efficiency and hypoxia resulting from apnea and hypopnea episodes,
all of which lead to a low testosterone level.
The aim of our study was to investigate hypogonadism in men
with obstructive sleep apnea and its related risk factors including : age
of the patient, body mass index (BMI), severity of obstructive sleep
apnea, smoking, positive family history and associated medical
conditions.
This case control study was carried out in Chest Diseases
outpatient clinics, Sleep Laboratory unit & Medical Biochemistry
Department, Faculty of Medicine, Menoufia University in the period
between December 2021 to June 2022 on 32 subjects, classified into 2
groups:
group 1: patients diagnosed as having obstructive sleep apnea.
group 2: healthy controls.
Summary
88
Subjects enrolled in this study, after taking written consent,
underwent history taking, assessment by sleep questionnaire (Epworth
Sleepiness Scale (ESS)), measurement of body mass index and neck
circumference, full night Polysomnography (PSG) and laboratory
investigations including serum LH & total testosterone levels.
In the present work, OSA patients had significantly higher
prevalence of associated chronic diseases (diabetes, hypertension and
irritable bowel syndrome), and taking antidiabetic and
antihypertensive medications and had significantly higher prevalence
of day time sleepiness than the controls (P = 0.030, 0.025 and <0.001
respectively).
OSA patients had significantly higher mean values of weight,
BMI and neck circumference than the control group (p<0.001). Also,
OSA patients had significantly higher mean values of serum LH levels
than the control group (p=0.031). Total testosterone levels were lower
in OSA patients than controls but it did not reach the significant level.
Furthermore, There was a significant negative correlation between
Epworth sleepiness scale and total testosterone levels in obstructive
sleep apnea patients (p=0.025).