Association between REM sleep and obstructive sleep apnea in obese and overweight adolescents

Effects of a 12-week walking intervention on circulating lipid profiles and adipokines in normal weight and abdominal obese female college students

Background/objectives

Regular exercise such as aerobic exercise has been shown to reduce the risk of some diseases such as cardiovascular disease (CVD). However, only few studies have investigated the impact of regular aerobic exercise on non-obese and overweight/obese persons. Therefore, this study was designed to compare the effect of a 12-week 10,000 steps a day walking intervention on the body composition, serum lipids, adipose tissue function, and obesity-associated cardiometabolic risk between normal weight and overweight/obese female college students.

Methods

Ten normal weight (NWCG) and 10 overweight/obese (AOG) individuals were recruited in this study. Both groups performed a regular 10,000 steps a day walk for 12 weeks. Their blood pressure, body mass index, waist-to-hip ratio, and blood lipid profiles were evaluated. Moreover, serum leptin and adiponectin levels were measured using an enzyme-linked immunosorbent assay.

Results

Our results revealed that triglyceride (TG), TG/high-density lipoprotein cholesterol (HDL-C) ratio and leptin were significantly reduced in the AOG group after the 12-week walking intervention. However, total cholesterol, HDL-C, and adiponectin/leptin ratio were significantly increased in the AOG group. There was little or no change in these variables in the NWCG group after the 12-week walking intervention.

Conclusions

Our study demonstrated that a 12-week walking intervention may help improve cardiorespiratory fitness and obesity-associated cardiometabolic risk by decrease resting heart rate, modulating blood lipid profiles, and inducing adipokine alterations in obese individuals. Therefore, our research encourages obese young adults to improve their physical health by participating in a 12-week walking program of 10,000 steps a day.

Polysomnography findings in preschool children with obstructive sleep apnea are affected by growth and developmental level

OBJECTIVE

We investigated the effect of growth and development level on polysomnography results in preschool children with obstructive sleep apnea (OSA).

METHODS

Preschool children (ages 3-6) with symptoms of snoring and were diagnosed with OSA by polysomnography in the sleep center were selected as the research object. They were split into three groups based on their growth rates: restricted, normal, and excessive. Sleep structure, respiratory events, and oxygenation index were compared between the three groups.

RESULTS

A total of 183 (111 boys and 72 girls) preschool children were enrolled. There were 26 cases in the growth restricted group, 112 cases in the normal growth group, and 45 cases in the overgrowth group. The weight and Body Mass Index (BMI) of children in the growth restricted and overgrowth groups were significantly different from those in the normal group. In terms of sleep structure, the sleep efficiency of the growth restricted group was poorer than that of the normal group. For sleep breathing events, the growth restricted group showed a greater apnea-hypopnea index (AHI), obstructive apnea hypopnea index (OAHI), hypoventilation index, and more hypoventilation than the normal group. In terms of oxygenation, the difference in degree of hypoxia between the three groups was statistically significant, and the overgrowth group had lower minimum oxygen saturation during the rapid eye movement phase than the normal group, as well as a quicker mean heart rate.

CONCLUSIONS

OSA is more likely in preschool-aged children with stunted or overgrown growth than in children with OSA alone, and the more severe the disorder, especially when accompanied with stunted growth.

Polysomnographic comparison of sleep in children with obesity and normal weight without suspected sleep-related breathing disorder

Short sleep and obstructive apneas/hypopneas have been shown to be associated with childhood obesity. Still, few studies have compared sleep in children with obesity, without suspected sleep disordered breathing and normal weight peers by objective sleep measures and compared results with subjective parent assessment of sleep. Children with obesity aged 7-13 years (N = 44) and a matched group of normal weight children (N = 42) completed clinical polysomnography (Embla A10 Recording System). Parents scored their children's sleep on the Children's Sleep Habits Questionnaire (CSHQ). Mann-Whitney U tests were used to compare groups. There was a higher obstructive apnea/hypopnea index (AHI) (median obesity = 1.20 vs. median normal  = 0.66; z = -1.33, U = 560.50, p = 0.002) and number of oxygen desaturation events per hour (median obesity = 0.7 vs. median normal  = 0.2; z = -3.45, U = 402.50, p = 0.001) in the children with obesity compared to children with normal weight. The children with obesity had a significantly longer sleep duration (median obesity 8:50 h = vs. median normal = 8:32 h; z = -2.05, U = 687.00, p = 0.041), longer stage N2 sleep (median obesity = 87 min vs. median normal = 52 min; z = -2.87, U = 576.50, p = 0. 004) and shorter REM sleep (median obesity = 94 min vs. median normal = 121 min; z = 5.05, U = 1477.00, p ≤ .001). No differences were observed for time in sleep stage N1 and N3, wake time after sleep onset or the total arousal index . Further, no group differences were found on the CSHQ sleep-disordered breathing sub-scale (p = 0.399). The children with obesity demonstrated significantly more mild to moderate sleep disordered breathing than children with normal weight, although this was not corroborated by parent report.

Clinical features of obstructive sleep apnea in children with obesity

OBJECTIVES

To study the clinical features of obstructive sleep apnea (OSA) in children with obesity.

METHODS

A retrospective analysis was performed on the medical data of 33 obese children aged 7-15 years, who were diagnosed with OSA and received polysomnography (PSG) in the Department of Respiratory Medicine in Shenzhen Children's Hospital. Fifty OSA children with normal body weight, matched for sex and age, were enrolled as the control group.

RESULTS

Among the 33 obese children with OSA, the three most common daytime symptoms were inattention in 30 children (91%), somnolence in 22 children (67%), and morning fatigue in 21 children (64%), and the three most common nocturnal symptoms were snoring in 27 children (82%), mouth breathing in 20 children (61%), and sweating in 16 children (49%). Compared with the reference values of normal children, both the OSA + obesity group and the control group had prolonged light sleep, shortened deep sleep, and a significantly shortened rapid eye movement (REM) period, while there was no significant difference in these indices between the two groups (P>0.05). The apnea-hypopnea index, obstructive apnea/hypopnea index, and oxygen desaturation index in both REM and non-REM periods in the OSA +obesity group were significantly higher than those in the control group (P<0.05), while the lowest blood oxygen saturation during sleep was significantly lower in the OSA + obesity group (P<0.05).

CONCLUSIONS

The children with obesity and OSA have the main daytime symptoms of inattention, somnolence, and morning fatigue and the main nocturnal symptoms of snoring, mouth breathing, and sweating. There is no significant difference in sleep structure between OSA children with obesity and those with normal body weight; however, respiratory events and blood oxygen saturation decline are more severe in OSA children with obesity. Citation.