Bidirectional Relationships Between Weight Change and Sleep Apnea in a Behavioral Weight Loss Intervention

Weight loss and lifestyle intervention for cardiorespiratory fitness in obstructive sleep apnea: The INTERAPNEA trial

INTRODUCTION

Although recent trials have shown benefits of weight loss and lifestyle interventions on obstructive sleep apnea (OSA) severity and comorbidities, the effect of these interventions on cardiorespiratory fitness (CRF) remains unknown. This study aimed to investigate the effects of an interdisciplinary weight loss and lifestyle intervention on CRF and self-reported physical fitness in adults with OSA.

METHODS

Eighty-nine men aged 18-65 years with moderate-to-severe OSA and a body mass index ≥25 kg/m2 were randomly assigned to a usual-care group or an 8-week interdisciplinary weight loss and lifestyle intervention. CRF was assessed through the 2-km walking test, and the International Fitness Scale (IFIS) was used to assess self-reported physical fitness.

RESULTS

As compared with usual-care, the intervention group had greater improvements at intervention endpoint in objective CRF (6% reduction in 2-km walking test total time, mean between-group difference, -1.7 min; 95% confidence interval, -2.3 to -1.1), and self-reported overall physical fitness (18% increase in IFIS total score, mean between-group difference, 2.3; 95% CI 1.2 to 3.3). At 6 months after intervention, the intervention group also had greater improvements in both 2-km walking test total time (10% reduction) and IFIS total score (22% increase), with mean between-group differences of -2.5 (CI 95%, -3.1 to -1.8) and 3.0 (CI 95%, 1.8 to 4.1), respectively.

CONCLUSIONS

An 8-week interdisciplinary weight loss and lifestyle intervention resulted in significant and sustainable improvements in CRF and self-reported physical fitness in men with overweight/obesity and moderate-to-severe OSA.

STUDY REGISTRATION

ClinicalTrials.gov registration (NCT03851653).

Weight Loss Outcomes in a Veterans Affairs Pharmacotherapy-based Weight Management Clinic

Context

Despite a high prevalence of obesity in the veteran population, antiobesity medications (AOMs) have been underused in the Veterans Health Administration. Real-world reports on outcomes when AOMs have been used in veterans is limited.

Objective

To analyze weight loss outcomes from a local Veterans Health Administration pharmacotherapy-based weight management clinic (WMC).

Methods

This was a retrospective cohort study of veterans enrolled in a local WMC for 15 months from August 2016 through September 2018 and followed through November 2019. Patients were offered 1 of 5 available AOMs based on their comorbidities. Factors associated with weight loss (5% or more weight loss) were assessed.

Key results

A total of 159 patients were seen in a WMC, 149 (93.7%) veterans were prescribed an AOM, and 129 returned for follow-up. Overall, 61/129 (47%) patients achieved 5% or greater weight loss and 28/129 (22%) achieved 10% or greater weight loss within 15 months. Clinically significant weight loss (%) over the first 15 months was achieved with phentermine/topiramate ER (-6.3%) and liraglutide (-7.5%), but not with orlistat (-3.9%) and lorcaserin (-3.6%). Comorbid obstructive sleep apnea was negatively associated with achieving ≥5% weight loss.

Conclusion

Phentermine/topiramate ER and liraglutide were found to be effective AOMs among veterans. Further work is needed to mitigate barriers to AOM initiation given the continued rise in obesity.

Effects of metformin on glucose metabolism and mitochondrial function in patients with obstructive sleep apnea: A pilot randomized trial

Obstructive sleep apnea (OSA) is associated with increased risk for diabetes, and standard treatment with positive airway pressure (PAP) device shows inconsistent effects on glucose metabolism. Metformin is known to treat and prevent diabetes, but its effects on skeletal muscle mitochondrial function are not completely understood. Here, we evaluate the effects of metformin on glucose metabolism and skeletal muscle mitochondrial function in patients with OSA. Sixteen adults with obesity (50.9 ± 6.7 years, BMI: 36.5 ± 2.9 kg/m2 ) and moderate-to-severe OSA were provided with PAP treatment and randomized to 3 months of placebo (n = 8) or metformin (n = 8) treatment in a double-blind parallel-group design. Whole body glucose metabolism was determined by oral glucose tolerance test. A skeletal muscle biopsy was obtained to evaluate mitochondrial respiratory capacity and expression of proteins related to mitochondrial dynamics and energy metabolism. Whole body insulin-sensitivity (Matsuda index) did not change in metformin or placebo treated groups. However, metformin treatment prevented increases in insulin release relative to placebo during follow-up. Insulin area under the curve (AUC) and insulin to glucose AUC ratio increased in placebo but remained unchanged with metformin. Furthermore, metformin treatment improved skeletal muscle mitochondrial respiratory capacity and dynamics relative to placebo. Metformin treatment prevented the decline in whole body glucose homeostasis and skeletal muscle mitochondrial function in patients with moderate to severe OSA. Patients with OSA may benefit from the addition of metformin to prevent diabetes.

Protocol for a pragmatic trial testing a self-directed lifestyle program targeting weight loss among patients with obstructive sleep apnea (POWER Trial)

BACKGROUND

Obesity comprises the single greatest reversible risk factor for obstructive sleep apnea (OSA). Despite the potential of lifestyle-based weight loss services to improve OSA severity and symptoms, these programs have limited reach. POWER is a pragmatic trial of a remote self-directed weight loss care among patients with OSA.

METHODS

POWER randomizes 696 patients with obesity (BMI 30-45 kg/m2) and recent diagnosis or re-confirmation of OSA 1:1 to either a self-directed weight loss intervention or usual care. POWER tests whether such an intervention improves co-primary outcomes of weight and sleep-related quality of life at 12 months. Secondary outcomes include sleep symptoms, global ratings of change, and cardiovascular risk scores. Finally, consistent with a hybrid type 1 approach, the trial embeds an implementation process evaluation. We will use quantitative and qualitative methods including budget impact analyses and qualitative interviews to assess barriers to implementation.

CONCLUSIONS

The results of POWER will inform population health approaches to the delivery of weight loss care. A remote self-directed program has the potential to be disseminated widely with limited health system resources and likely low-cost.

Identifying Predictors of Adherence to the Physical Activity Goal: A Secondary Analysis of the SMARTER Weight Loss Trial

INTRODUCTION/PURPOSE

Research is needed to inform tailoring supportive strategies for promoting physical activity (PA) in the context of behavioral treatment of obesity. We aimed to identify baseline participant characteristics and short-term intervention response predictors associated with adherence to the study-defined PA goal in a mobile health (mHealth) weight loss trial.

METHODS

A secondary analysis was conducted of a 12-month weight loss trial (SMARTER) that randomized 502 adults with overweight or obesity to either self-monitoring of diet, PA, and weight with tailored feedback messages ( n = 251) or self-monitoring alone ( n = 251). The primary outcome was average adherence to the PA goal of ≥150 min·wk -1 of moderate- and vigorous-intensity aerobic activities (MVPA) from Fitbit Charge 2™ trackers over 52 wk. Twenty-five explanatory variables were considered. Machine learning methods and linear regression were used to identify predictors of adherence to the PA goal.

RESULTS

The sample ( N = 502) was mostly female (80%), White (82%) with the average age of 45 ± 14.4 yr and body mass index of 33.7 ± 4.0 kg·m -2 . Machine learning methods identified PA goal adherence for the first week as the most important predictor of long-term PA goal adherence. In the parsimonious linear regression model, higher PA goal adherence for the first week, greater PA FB messages opened, older age, being male, higher education, being single and not having obstructive sleep apnea were associated with higher long-term PA goal adherence.

CONCLUSIONS

To our knowledge, this is the first study using machine learning approaches to identify predictors of long-term PA goal adherence in a mHealth weight loss trial. Future studies focusing on facilitators or barriers to PA among young and middle-age adults and women with low PA goal adherence are warranted.

Designing a program to support weight loss for patients attending the sleep medicine clinic: a qualitative study

STUDY OBJECTIVES

Excess body weight is the most important risk factor in sleep-disordered breathing. Weight loss is a treatment alternative to positive airway pressure therapy, but there is a knowledge gap of what is feasible, acceptable, and sustainable in this population. We seek to add the voices of sleep medicine patients and providers to the medical literature to understand what makes this population unique when considering weight loss, and what we can do differently to create more sustainable weight loss interventions.

METHODS

We conducted one-on-one semistructured interviews with 12 patients with obstructive sleep apnea/obesity hypoventilation syndrome and obesity and with 9 sleep medicine providers regarding previous weight loss efforts, perceptions of barriers to and facilitators of weight loss, and potential components of a program to support those with sleep apnea and excess weight.

RESULTS

Patients indicated they appreciated direct conversation with their sleep physician regarding weight loss and providers felt the patient population was generally very receptive to weight loss conversations. Patients emphasized the most important aspects of a future weight loss program would be personalized diet, exercise, accountability, integration of technology, and an individualized approach to addressing the psychological aspects of eating.

CONCLUSIONS

This is a unique population of patients who are very receptive to conversations about weight loss. We plan to use this data to inform a future weight loss program based in health coaching to address the specific needs of this population.

CITATION

Dupuy-McCauley K, Benzo R, Barwise A. Designing a program to support weight loss for patients attending the sleep medicine clinic: a qualitative study. J Clin Sleep Med. 2023;19(3):459-471.

Causal associations of sleep apnea and snoring with type 2 diabetes and glycemic traits and the role of BMI

OBJECTIVE

Sleep apnea and snoring have been associated with type 2 diabetes, with BMI playing a role in the pathway, but the directions of causality are unclear. This study examined the causal associations of sleep apnea and snoring with type 2 diabetes while assessing the role of BMI using multiple genetic methods.

METHODS

Five genetic methods were used: two-sample; bidirectional univariable Mendelian randomization (MR) inverse variance-weighted (MR-IVW); multivariable MR-IVW; network MR; and latent causal variable method.

RESULTS

Compared with univariable MR-IVW, the odds ratio (95% CI) of type 2 diabetes for genetically predicted sleep apnea and snoring using the largest genome-wide association study decreased dramatically, from 1.61 (95% CI: 1.16-2.23) to 1.08 (95% CI: 0.59-1.97) and from 1.98 (95% CI: 1.25-3.13) to 1.09 (95% CI: 0.64-1.86) after adjustment for BMI. Network MR showed that BMI accounts for 67% and 62% of the total effect of sleep apnea and snoring on type 2 diabetes, respectively. The latent causal variable suggested that sleep apnea and snoring have no direct causal effect on type 2 diabetes.

CONCLUSIONS

These results first suggest that the associations of sleep apnea and snoring with type 2 diabetes were mainly driven by BMI. The possible indirect effects of sleep apnea and snoring on type 2 diabetes through BMI cannot be ruled out.

Body weight and obstructive sleep apnea: a mathematical relationship between body mass index and apnea-hypopnea index in veterans

STUDY OBJECTIVES

A high body mass index (BMI) is a risk factor for obstructive sleep apnea. However, to our knowledge there is no reported equation that quantifies the relationship between weight, as measured by BMI, and apnea severity, as assessed by the apnea-hypopnea index (AHI). Our objective was to find a mathematical relationship between BMI and AHI.

METHODS

We prospectively recruited 434 veterans from our polysomnography laboratory. Veterans already undergoing a sleep study were approached, and those who consented were enrolled. The veterans who enrolled in our study also participated in their scheduled sleep study. This study was approved by our institutional review board.

RESULTS

We found a simple mathematical relationship between BMI and AHI: for every 1-point drop in BMI (corresponding to 5-8 pounds, depending on a person's height), AHI decreases by 6.2%. And limiting BMI to 25-40 kg/m2 (which includes about 80% of the BMIs), then AHI drops by 7.1%. Simply put as a rule of thumb: For every 7-pounds drop in weight, expect a 7% drop in AHI.

CONCLUSIONS

To our knowledge, this is the first simple mathematical equation that associates the severity of weight with the severity of apnea in veterans. This equation can be a practical rule of thumb that can be implemented in clinics to predict the amount of weight a patient needs to lose to decrease their apnea, which might help motivate patients to lose weight.

CITATION

Fattal D, Hester S, Wendt L. Body weight and obstructive sleep apnea: a mathematical relationship between body mass index and apnea-hypopnea index in veterans. J Clin Sleep Med. 2022;18(12):2723-2729.

The impact of thyroidectomy on obstructive sleep apnea: a systematic review and meta-analysis

PURPOSE

Various thyroid pathologies are speculated to contribute to obstructive sleep apnea (OSA). The underlying mechanisms of the intricate relationship between OSA and thyroid structure and function, and whether thyroidectomy can alleviate OSA symptoms remain unclear. An assessment of the impact of thyroidectomy on OSA is warranted.

METHODS

A systematic review of four electronic databases (PubMed (Medline), Embase, the Cochrane library, and ClinicalTrials.gov) was performed up to February 2022. The primary outcomes were preoperative and postoperative Apnea/Hypopnea Index (AHI), Epworth Sleepiness Scale (ESS), Berlin questionnaire scores, and continuous positive airway pressure (CPAP) use. A meta-analysis of continuous measures and odd ratios was conducted. Small-scale studies underwent a qualitative meta-analysis.

RESULTS

Six cohort studies on 221 OSA patients who underwent thyroidectomies were included. The results showed that thyroidectomy was associated with significant reduction in postoperative AHI (Mean difference [MD], -6.39, 95% CI, -12.46 to -0.32), however, no significant association was found with CPAP withdrawal (Odd ratio [OR], 0.38, 95% CI, 0.12-1.18). Neither the Berlin questionnaire score (OR, 0.19, 95% CI, 0.03-1.17) nor the ESS improved postoperatively (MD, -1.04, 95% CI, -6.37 to 4.29).

CONCLUSION

This meta-analysis provides a quantitative estimate for the effect of the thyroidectomy on OSA and suggests that thyroidectomy is associated with limited clinical improvement of polysomnographic measures. Future large-scale, well-designed prospective studies are necessary to validate these findings and to refine accordingly the preoperative assessment of both medical conditions individually and in combination.

Impact of a Weight-Loss Rehabilitation Program on Sleep Apnea Risk and Subjective Sleepiness in Patients with Overweight/Obesity: The DietSleep Study

Obstructive sleep apnea (OSA) is one of the most frequent chronic diseases, and comorbid obesity occurs in more than 60% of cases. Variations in body weight influence both OSA severity and OSA-related symptoms. We prospectively assessed the impact of a weight-loss program using the Berlin score to reflect OSA risk, and we also used the Epworth Sleepiness Scale (ESS) to assess daytime sleepiness. DietSleep was a prospective multicentric cohort study investigating OSA risk and daytime sleepiness before and after weight-loss intervention. One hundred and twenty-seven patients were included (initial OSA risk 36%), most of whom were women (85.8%) with a median body mass index (BMI) of 29.7 kg/m2, and the interquartile range was (27.6; 34). The diet-based weight-loss program induced a median decrease in BMI of 3.7 kg/m2 (−5; −2.9) (body weight~12.1% (−16.0; −8.8)) over a period of 171 days (114; 269). Changes in anthropometric values were similar regarding OSA risk after adjusting for initial values. Berlin scores significantly improved from 3 (1; 5) to 1 (0; 2), p < 0.01; the proportion of patients with a Berlin score ≥2 decreased from 36% to 7% after the intervention. The proportion of patients with ESS ≥11 decreased from 13% to 2%. These results confirm that a weight-loss program produces clinically relevant weight loss and a significant improvement in both OSA and subjective daytime sleepiness.

Effect of sleep on weight loss and adherence to diet and physical activity recommendations during an 18-month behavioral weight loss intervention

BACKGROUND/OBJECTIVES

To examine the association between indices of sleep quantity and quality with dietary adherence, physical activity adherence, and weight loss during a behavioral weight loss intervention.

METHODS

Adults (n = 156) with overweight and obesity (40 ± 9 years, 84% female, BMI: 34.4 ± 4.2 kg/m²) participated in an 18-month behavioral weight loss intervention which prescribed a reduced calorie diet (1200-1800 kcal/d) and increased physical activity (300 min/wk). Body weight, indices of sleep (SenseWear armband; SWA), energy intake (EI, 3-day food records), and moderate-to-vigorous physical activity (SWA) were measured at baseline, 6, 12, and 18 months. Linear mixed effects models examined the association between sleep and weight change over time. Additional models were adjusted for covariates including age, BMI, sex, race, ethnicity, study completion, randomization, EI, and physical activity. Secondary analyses examined the association between sleep and adherence to diet and physical activity recommendations.

RESULTS

Mean weight loss was 7.7 ± 5.4, 8.4 ± 7.9, and 7.1 ± 9.0 kg at 6, 12, and 18 months, respectively. Lower sleep efficiency, higher wake after sleep onset (WASO), more awakenings, and higher sleep onset latency (SOL) were significantly associated with attenuated weight loss (p < 0.05). Lower sleep efficiency, more awakenings, and higher SOL remained significantly associated with blunted weight loss after adjustment for covariates (p < 0.05). Later waketime, longer time in bed, longer sleep duration, higher WASO, more awakenings, and higher SOL were associated with lower odds of achieving ≥300 min/wk of moderate-to-vigorous physical activity, adjusted for covariates (FDR p < 0.05).

CONCLUSIONS

Future studies should evaluate whether incorporating strategies to improve sleep health within a behavioral weight loss intervention leads to improved adherence to diet and physical activity recommendations and enhanced weight loss.

CLINICAL TRIALS IDENTIFIER

NCT01985568.

Change in Objectively Measured Activity Levels Resulting from the EMPOWER Study Lifestyle Intervention

Purpose

To examine changes in physical activity (PA) during a behavioral weight-loss intervention and determine baseline factors associated with PA goal achievement.

Methods

Overweight/obese community-dwelling adults with valid PA accelerometer data (N=116; mean age 51.7 years; 89% female; 83% non-Hispanic White) were recruited into a single-arm prospective cohort study examining the effects of a 12-month intervention that included 24 in-person group sessions, weight-loss, calorie, fat gram, and PA goals, self-monitoring, and feedback. Minutes of moderate-to-vigorous (MV) PA and steps were measured using a waist-worn accelerometer (ActiGraph GT3x) at baseline, 6 months, and 12 months. Achievement of the 150 minute/week MVPA goal was examined using total minutes and bout minutes (i.e., counting only PA occurring in bouts ≥10 minutes in length). Change in PA was analyzed using non-parametric tests for multiple comparisons. Associations of factors with meeting the PA goal were modeled using binary logistic regression.

Results

At 6 months, there were increases from baseline in MVPA (median [p25, p75]: 5.3 [-0.9, 17.6] minutes/day) and steps (863 [-145, 2790] steps/day), both p<0.001. At 12 months, improvements were attenuated (MVPA: 2.4 [-2.0, 11.4] minutes/day, p=0.047; steps: 374[-570, 1804] p=0.14). At 6 months, 33.6% of individuals met the PA goal (using total or bout minutes). At 12 months, the percent meeting the goal using total MVPA [31%] differed from bout MVPA [22.4%]. Male gender (OR=4.14, p=0.027) and an autumn program start (versus winter; OR=3.39, p=0.011) were associated with greater odds of goal achievement at 6 months.

Conclusions

The intervention increased PA goal achievement at 6 and 12 months with many making clinically meaningful improvements. Our results suggest female participants may require extra support toward improving PA levels.

Bariatric surgery short-term outcomes in patients with obstructive sleep apnoea: the Severe Obesity Outcome Network prospective cohort

BACKGROUND/OBJECTIVES

Although the benefits of bariatric surgery have been clearly established, it is not known whether they are as important in patients with obstructive sleep apnoea (OSA). Primary aim: to evaluate whether patients with moderate-to-severe OSA (apnoea-hypopnea index (AHI) ≥ 15 events/h) treated by continuous positive airway pressure/non-invasive ventilation (median [IQR] adherence 6.5 h/night [5; 7.9] at baseline) lose the same amount of body weight 1 year after bariatric surgery as patients with no or mild OSA. Secondary objectives: to compare the evolution of type 2 diabetes and hypertension after bariatric surgery, and surgical complication rates between groups.

METHODS/SUBJECTS

Analyses were performed in 371 patients included in a prospective cohort of bariatric surgery, the Severe Obesity Outcome Network cohort. Subjects having moderate-to-severe OSA (n = 210) at baseline were compared with other subjects (n = 161).

RESULTS

Excess weight loss (%EWL) at 1 year was lower in patients with moderate-to-severe OSA than in patients without (64.9%EWL [46.9; 79.5] vs. 73.8%EWL [56.6; 89.3], p < 0.01). Multivariable analysis showed that age, initial body mass index and type of surgery, but not OSA status, were associated with 1-year %EWL. Diabetes remitted in 25 (41%) patients with moderate-to-severe OSA and 16 (48%) patients with no or mild OSA (p = 0.48). Hypertension remitted in 28 (32.9%) patients with moderate-to-severe OSA and 9 (40.9%) with no or mild (p = 0.48). Complication rates were 28 (13.3%) in patients with moderate-to-severe OSA and 12 (7.5%) in patients with no or mild OSA (p = 0.07).

CONCLUSIONS

Patients with OSA lose less body weight after bariatric surgery. This was related to older age and a higher baseline body mass index. However, the improvements of diabetes and hypertension were similar to that of patients without OSA, and the risk of surgical complications was not higher.

Bidirectional relationship between sleep and sedentary behavior in adults with overweight or obesity: A secondary analysis

Study Objectives

The relationships between daytime sedentary behavior and that night’s sleep and sleep and next day’s sedentary behavior are unknown. The purpose of this analysis was to examine these potentially bidirectional associations.

Methods

This study was a secondary analysis of baseline data from an ecological momentary assessment study to determine the triggers for dietary lapses during a weight loss intervention. Sedentary behavior, physical activity, and sleep were objectively measured using accelerometers. Linear mixed modeling was used to examine the bidirectional multivariate associations between activity and sleep characteristics for each outcome examined separately. The models included sex, age, body mass index (BMI), education, and day of the week (weekday vs. weekend).

Results

Participants were predominantly white (81.5%) and female (88.9%) with a mean age of 51.2 ± 10.6 years. Longer previous night’s total sleep time (TST) (b = −0.320, standard error [SE] = 0.060; p < .001) and being a weekend (b = −63.845, SE = 9.406; p < .001) were associated with less sedentary time the next day. More daytime sedentary time was associated with less wake after sleep onset (b = −0.018, SE = 0.008; p = .016), fewer awakenings (b = −0.010, SE = 0.004; p = .016), and less TST (b = −0.060, SE = 0.028; p = .029) that night.

Conclusions

The bidirectional relationships between sedentary time and sleep characteristics are complex and may vary depending on participant characteristics and duration of sedentary and sleep time. Interventions to decrease sedentary behavior may benefit by targeting sleep duration and weekday activity.

Sleep and Metabolic Syndrome

Metabolic syndrome (MetS) refers to the clustering of risk factors for cardiovascular disease and diabetes, including central adiposity, hypertension, dyslipidemia, and hyperglycemia. During the past 20 years, there have been parallel and epidemic increases in MetS and impaired sleep. This article describes evidence on the association between MetS and short sleep duration, circadian misalignment, insomnia, and sleep apnea. Potential mechanisms where impaired sleep desynchronizes and worsens metabolic control and interventions to improve sleep and potentially improve MetS are presented.

The association between sleep health and weight change during a 12-month behavioral weight loss intervention

BACKGROUND

Prior research on the relationship between sleep and attempted weight loss failed to recognize the multidimensional nature of sleep. We examined the relationship between a composite measure of sleep health and change in weight and body composition among adults in a weight loss intervention.

METHODS

Adults (N = 125) with overweight or obesity (50.3 ± 10.6 years, 91% female, 81% white) participated in a 12-month behavioral weight loss intervention, with assessments of sleep, weight, fat mass, and fat-free mass at baseline, 6 months, and 12 months. Six sleep dimensions (regularity, satisfaction, alertness, timing, efficiency, and duration) were categorized as "good" or "poor" using questionnaires and actigraphy. A composite score was calculated by summing the number of "good" dimensions. Obstructive sleep apnea (OSA) was assessed in a subsample (n = 117), using the apnea-hypopnea index (AHI) to determine OSA severity. Linear mixed modeling was used to examine the relationships between sleep health and outcomes of percent weight, fat mass, or fat-free mass change during the subsequent 6-month interval, adjusting for age, sex, bed partner, and race; an additional model adjusted for AHI.

RESULTS

Mean baseline and 6-month sleep health was 4.5 ± 1.1 and 4.5 ± 1.2, respectively. Mean weight, fat mass, and fat-free mass changes from 0 to 6 months were -9.3 ± 6.1%, -16.9 ± 13.5%, and -3.4 ± 3.4%, respectively, and 0.4 ± 4.8%, -0.3 ± 10.3%, and 0.7 ± 4.1% from 6 to 12 months. Better sleep health was associated with greater subsequent weight loss (P = 0.016) and fat loss (P = 0.006), but not fat-free mass loss (P = 0.232). Following AHI adjustment, the association between sleep health and weight loss was attenuated (P = 0.102) but remained significant with fat loss (P = 0.040). Regularity, satisfaction, timing, and efficiency were each associated with weight and/or fat loss (P ≤ 0.041).

CONCLUSIONS

Better sleep health was associated with greater weight and fat loss, with associations attenuated after accounting for OSA severity. Future studies should explore whether improving sleep health, OSA, or the combination improves weight loss.

Metabolic Consequences of Obstructive Sleep Apnea Especially Pertaining to Diabetes Mellitus and Insulin Sensitivity

Obstructive sleep apnea (OSA) and diabetes has been known to be closely related to each other and both diseases impact highly on the public health. There are many evidence of reports that OSA is associated with diabetes with a bidirectional correlation. A possible causal mechanism of OSA to diabetes is intermittent hypoxemia and diabetes to OSA is microvascular complication. However, OSA and diabetes have a high prevalence rate in public and shares the common overlap characteristic and risk factors such as age, obesity, and metabolic syndrome that make it difficult to establish the exact pathophysiologic mechanism between them. In addition, studies demonstrating that treatment of OSA may help prevent diabetes or improve glycemic control have not shown convincing result but have become a great field of interest research. This review outlines the bidirectional correlation between OSA and diabetes and explore the pathophysiologic mechanisms by approaching their basic etiologies.