Plasma dehydroepiandrosterone sulphate and insulin-like growth factor I levels in obstructive sleep apnoea syndrome

The correlation of serum/plasma IGF-1 concentrations with obstructive sleep apnea hypopnea syndrome: A meta-analysis and meta-regression

BACKGROUND

Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common disease that has serious cardiovascular and metabolic effects. Insulin-like growth factor 1 (IGF-1) levels are reportedly reduced in patients with OSAHS; however, this is still a matter of debate. Therefore, we investigated the association between serum/plasma IGF-1 levels and OSAHS in this meta-analysis.

METHODS

Wan Fang, Excerpta Medica dataBASE, Web of Science, China National Knowledge Infrastructure, VIP, PubMed, and other databases were searched for materials published in any language before April 2, 2022. Two researchers analyzed the studies for quality according to the Newcastle-Ottawa Scale. The acquired data were analyzed using Stata 11.0 and R 3.6.1 software. The effect size was estimated and calculated using standard mean differences and correlation coefficients. Moreover, a combined analysis was conducted using either a random- or fixed-effects model.

RESULTS

Ultimately, 34 studies met our inclusion criteria. Our findings revealed that the plasma/serum IGF-1 concentrations in patients with OSAHS was significantly reduced compared with those in healthy subjects. Subgroup analyses were performed according to OSAHS severity, ethnicity, age, body mass index, specimen testing method, and study design. The outcomes suggested that nearly all subgroups of patients with OSAHS had reduced serum IGF-1 levels. Disease severity and differences in ethnicity were identified as possible influencing factors of serum IGF-1 levels in patients with OSAHS in the meta-regression analysis, and no other factors were found to alter plasma/serum IGF-1 concentrations. Moreover, plasma/serum IGF-1 concentrations were negatively correlated with apnea-hypopnea index and oxygen desaturation index scores and positively associated with minimum oxygen saturation.

CONCLUSION

Serum/plasma IGF-1 concentrations in patients with OSAHS were greatly reduced compared with those of patients in the control group, and were negatively correlated with apnea-hypopnea index and oxygen desaturation index scores and positively correlated with minimum oxygen saturation.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022322738.

Relationship between circulating insulin-like growth factor-1 and blood pressure in adults: A systematic review and meta-analysis of observational studies

OBJECTIVE

Insulin-like growth factor 1 (IGF-1) is an important factor related to cardiovascular disease. In recent years, studies have shown the involvement of IGF-1 and blood pressure (BP). Nevertheless, the results were inconsistent. Thus, the purpose of this study was to systematically evaluate the associations of circulating IGF-1 levels with BP in adults.

METHODS

Two reviewers independently searched and screened articles from the Pubmed, EMBASE, Cochrane Library, CNKI, and WANFANG databases up to May 2020. A total of 12 studies that reported the correlation coefficients between IGF-1, systolic blood pressure (SBP), and diastolic blood pressure (DBP) were included.

RESULTS

IGF-1 was significantly correlated with SBP [r = -0.15; 95% CI = -0.21, -0.08; P < 0.0001] and DBP [r = -0.10; 95% CI = -0.16, -0.05; P = 0.0004]. Subgroup analysis further revealed that the relationship between IGF-1 and BP was influenced by race and age.

CONCLUSION

Circulating IGF-1 was negatively correlated with SBP and DBP. Further researches are necessary to explore the pathogenesis of this relationship and to evaluate the role of IGF-1 in the treatment of hypertension.

The severity of obstructive sleep apnoea does not influence ambient IGF-I levels

OBJECTIVE

Obstructive sleep apnoea (OSA) is reported to have effects on a number of hormone systems including the hypothalamo-pituitary axis. We aimed to determine the impact of OSA severity on insulin-like growth factor-I (IGF-I) levels.

DESIGN AND METHODS

This is a prospective cohort study performed between November 2014 and May 2017. IGF-I was measured on serum samples, and data were collected on demographics, BMI and parameters of OSA.

RESULTS

611 participants were recruited (202 female, 53.5 ± 12.5 years; mean BMI 36.2 ± 8.0 kg/m² ). 26.2% had mild OSA; 27.3%, moderate OSA; and 44.5%, severe OSA. 15.2% of IGF-I values were below the age-related reference range. Increasing BMI correlated with greater AHI (r = .28, p < .001), ODI (r = .30, p < .001), severity of OSA (r = .17, p < .001), duration with oxygen saturation (SaO₂ ) <90% (r = .29, p = .001) and reduced median SaO₂ levels (r = .19, p < .001). IGF-I levels correlated negatively with age (r = -.13, p = .001), BMI (r = -.16, p < .001), diabetes (r = -.108, p = .009), AHI (r = -0.10, p = .043) and severity of OSA (r = -.10, p = .013). No association of IGF-I was observed with ODI, median SaO₂ levels or duration of SaO₂  < 90%. Regression analyses were used to examine determinants of IGF-I, all of which contained the independent variables of age, gender and BMI. All models showed IGF-I to be predicted by age and BMI (p < .05); however, none of the parameters of OSA were significant within these models.

CONCLUSION

Insulin-like growth factor-I levels in OSA are dependent on age and BMI; however, no additional effect of any OSA parameter was observed, supporting the hypothesis that OSA effects on IGF-I are indirect through concomitant body composition and metabolic parameters.

Effects of CPAP therapy on subcutaneous adipose tissue in patients with obstructive sleep apnea: a meta-analysis

PURPOSE

Continuous positive airway pressure (CPAP) is an effective treatment for obstructive sleep apnea (OSA). However, studies provide conflicting results on the effects of CPAP on subcutaneous adipose tissue (SAT) in patients with OSA. We therefore performed a meta-analysis to evaluate whether or not CPAP has an effect on SAT in patients with OSA.

METHODS

Studies were retrieved by searching the Cochrane Library, Web of Science, Embase, and Pubmed. Information on study and patient characteristics, study design, and SAT pre- and post-CPAP treatment was extracted for analysis. Different methods for measurement of SAT were also notated. Standardized mean difference (SMD) and 95% confidence interval (CI) were measured to estimate the change in SAT before and after CPAP treatment. Meta-analysis was performed using the RevMan v.5.3 and Stata 14.0.

RESULTS

A total of 10 studies met inclusion criteria encompassing 309 patients in the final analysis. The pooled estimate showed that CPAP treatment resulted in no significant change in SAT (SMD = - 0.014, 95% CI = - 0.161 to 0.133, p = 0.896). Meta-regression analyses revealed no predictor, including methods of measuring SAT, that influenced the CPAP effect on SAT.

CONCLUSION

Our meta-analysis demonstrated that after CPAP therapy, there was no significant change in SAT in patients with OSA.

The Somatotropic Axis in the Sleep Apnea-Obesity Comorbid Duo

Background: Growth hormone (GH) stimulates the production of insulin-like growth factor 1 (IGF-1) in most tissues and together GH and IGF-1 profoundly impact adipose tissue deposition, glucose metabolism and cardiovascular function. A low serum IGF-I level has been reported as being associated with obstructive sleep apnea (OSA) and might be one of the mechanisms underlying cardio-metabolic risk in OSA patients. Methods: In a multicenter national study, 817 patients consulting for suspicion of OSA (OSA confirmed for 567 patients) underwent serum IGF-1 measurements. We analyzed the association between an IGF-1 level below the median value of the population and variables related to cardio-metabolic risk: body mass index (BMI) and waist circumference, apnea hypopnea index (AHI), cholesterol and triglycerides (expressed as median and divided into quartiles for continuous variables). Results: After adjustment for age and gender, low IGF-1 levels were associated with increased BMI and AHI (Odds ratios (OR) = 2.83; p < 0.0001 and OR = 3.03, p < 0.0001 for Quartile 4 vs. Quartile1, respectively), with elevated cholesterol levels (OR = 1.36, p = 0.0444), and elevated triglyceride levels (OR = 1.36; p = 0.0008). Conclusions: Both adiposity and sleep apnea synergistically predict low levels of IGF-1 and thus could together contribute toward cardio-metabolic risk. Further work are needed to confirm whether IGF-1 levels allow grading severity and predicting response to treatments to aim at a personalized medicine for patients suffering from OSA.

Effects of CPAP on visceral adipose tissue in patients with obstructive sleep apnea: a meta-analysis

PURPOSE

The efficacy of obstructive sleep apnea (OSA) treatment with continuous positive airway pressure (CPAP) on visceral adipose tissue (VAT) yielded conflicting results. This meta-analysis was performed to assess whether OSA treatment with CPAP could reduce VAT.

METHODS

The PubMed, Cochrane Library, Embase, and Web of Science were searched before April 2019. Information on characteristics of study participants, pre- and post-CPAP treatment of VAT, and study design was utilized for analysis. Standardized mean difference (SMD) and 95% confidence interval (CI) were used to fully analyze the overall effects. Eleven studies were obtained and the meta-analysis was performed using RevMan v.5.2 and STATA 12.0.

RESULTS

A total of 11 studies (16 cohorts) were pooled into meta-analysis, which included 398 patients. The value of VAT before and after CPAP treatment showed no change in OSA patients (SMD = - 0.02, 95% CI - 0.16 to 0.12, z = 0.24, p = 0.81). Subgroup analyses were further conducted, which revealed that age, gender distribution, baseline body mass index, daily duration, CPAP therapy duration, measure, sample size, and study design did not affect the results.

CONCLUSIONS

This meta-analysis revealed that CPAP therapy has no effect on VAT in OSA patients. Further large-scale, well-designed randomized controlled trials are required to address this issue.

The Impact of Continuous Positive Airway Pressure on Circulating IGF-1 in Patients With Obstructive Sleep Apnea

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a disease with metabolic and cardiovascular consequences and is associated with decreased serum concentrations of insulin-like growth factor-1 (IGF-1). The aim of this study was to investigate whether continuous positive airway pressure (CPAP) will increase serum IGF-1 concentration in patients with OSA.

METHODS

Patients with moderate to severe OSA were recruited from a sleep clinic and serum IGF-1 was measured before initiation of CPAP and at follow-up after 4.8 ± 2.5 months. Patients adherent to CPAP treatment (usage ≥ 4 h/night) were compared with those considered to be nonadherent (usage < 4 h/night).

RESULTS

Complete data were obtained from 69 patients (86% male, age 56 ± 12 years, respiratory event index 43 ± 21 events/h, Epworth Sleepiness Scale score 12 ± 5). In those adherent to CPAP (n = 42), there was an increase in serum IGF-1 concentration with 21.1 (95% confidence interval [CI]: 13.1 to 29.2) μg/L compared to 4.7 (95% CI: -4.1 to 13.5) μg/L in the nonadherent group (n = 27) (P = .0083). In a linear multivariate model adjusting for sex, age, body mass index, respiratory event index, and mean oxygen saturation during the night recording, the change in serum IGF-1 concentration was significantly associated with adherence to CPAP treatment (adjusted β coefficient: 21.8, 95% CI: 10.2 to 33.4) and inversely associated with change in body mass index (adjusted β coefficient: -7.1, 95% CI: -11.3 to -3.0) and change in hemoglobin A1c (adjusted β coefficient: -1.8, 95% CI: -33 to -0.3).

CONCLUSIONS

CPAP usage ≥ 4 h/night is associated with increased serum IGF-1 concentration in male patients with OSA.

Alterations of IGF-1, complement C3 and superoxide dismutase in patients with moderate-to-severe obstructive sleep apnea hypopnea syndrome

AIM

To evaluate various biomarkers of metabolism, immunity and inflammation in obstructive sleep apnea hypopnea syndrome (OSAHS).

MATERIALS & METHODS

After overnight polysomnography, blood was collected from 292 OSAHS patients or healthy volunteers. Serum content of inflammatory, immune, metabolic biomarkers were investigated. In addition, the effects of 1-month continuous positive airway pressure (CPAP) were studied in moderate/severe OSAHS.

RESULTS

C3, serum total complement activity, superoxide dismutase, uric acid were significantly higher in moderate/severe OSAHS than that in no/mild OSAHS. In contrast, IGF-1 in moderate/severe OSAHS was lower than it in no/mild OSAHS, which was negative correlated with apnea-hypopnea index. Moreover, CPAP significantly decreased C3, meanwhile elevated IGF-1.

CONCLUSION

C3, serum total complement activity and superoxide dismutase were higher in moderate/severe OSAHS, while IGF-1 decreased. Elevated C3 and reduced IGF-1 in moderate/severe OSAHS may be reversed by CPAP.

Relationship between sleep parameters, insulin resistance and age-adjusted insulin like growth factor-1 score in non diabetic older patients

BACKGROUND

Sleep complaints are prevalent in older patients. Sleepiness, short or long sleep duration and obstructive sleep apnea (OSA) are associated with insulin resistance (IR). These parameters have not yet been considered together in the same study exploring the possible association between IR and sleep in older patients. IR is involved in cardiovascular and metabolic diseases, pathologies which are highly prevalent in older patients. Here we assess, in older non-diabetic patients with sleep complaints, the associations between IR and sleep parameters objectively recorded by polysomnography (PSG) rather than self-report. The Growth Hormone/Insulin like growth factor-1 axis could play a role in the development of IR during sleep disorders. The second objective of this study was to analyze the association between sleep parameters and age-adjusted IGF-1 score, which could explain the association between OSA and IR.

METHODS

72 non-diabetic older patients, mean age 74.5 ± 7.8 years, were included in this observational study. We evaluated anthropometric measures, subjective and objective sleepiness, polysomnography, Homeostatic Model Assessment for IR (HOMA-IR) and age-adjusted IGF-1 score. A multivariate regression was used to determine factors associated with HOMA-IR.

RESULTS

The 47 OSA patients were over-weight but not obese and had higher IR than the non-OSA patients. In multilinear regression analysis, apnea-hypopnea index was independently associated with IR after adjustment for several confounding factors. Neither IGF-1 level nor IGF-1 score were different in the two groups.

CONCLUSIONS

We demonstrate that in non-diabetic older patients with sleep complaints, OSA is independently associated with IR, regardless of anthropometric measurements and sleep parameters (sleep duration/sleepiness/arousals). Targeting OSA to reduce IR could be useful in the elderly, although further exploration is required.

IGF-1 Levels are Inversely Associated With Metabolic Syndrome in Obstructive Sleep Apnea

STUDY OBJECTIVES

This study examined insulin-like growth factor-1 (IGF-1) production and its association with the metabolic syndrome (MS) in men with obstructive sleep apnea (OSA).

METHODS

In total, 47 overweight and obese men who had been referred for suspected OSA underwent polysomnography and were classified based on the apnea-hypopnea index (AHI) into three groups: no OSA, < 5 events/h (n = 11); mild OSA, ≥ 5 to < 15 events/h (n = 8); and moderate-severe OSA, ≥ 15 events/h (n = 28). The assessment of the somatotropic axis function included IGF-1 measurement. MS was diagnosed according to the National Cholesterol Education Program guidelines.

RESULTS

IGF-1 level in the moderate-severe OSA group was lower than in the no-OSA group (156.8 ± 54.3 μg/L versus 225.5 ± 80.5 μg/L; p = 0.013). IGF-1 level was negatively correlated with body mass index, waist circumference (WC), AHI, and sleep duration with oxygen (O2) saturation < 90% and positively correlated with the average and minimum O2 saturation (p = 0.027). In a multivariable linear regression, considering WC and minimum O2 saturation as independent variables, only the minimum O2 saturation was a predictor of low IGF-1 levels. The proportions of patients with MS were different between the three groups (18.2% in no OSA; 25% in mild OSA, and 57.1% in moderate-severe OSA; p = 0.047). Furthermore, in the lowest tertile of IGF-1 value, 66.7% of patients were affected by MS (p = 0.049). Hemoglobin (Hb)A1c correlated negatively with the minimum O2 saturation and IGF-1 levels. However, in multivariable linear regression only IGF-1 levels were a predictor of HbA1c levels.

CONCLUSION

The occurrence of OSA is associated with a reduction in IGF-1 levels. IGF-1 alterations in OSA also seem to be associated with a higher prevalence of MS.

Association between Serum IGF-I levels and Postoperative Delirium in Elderly Subjects Undergoing Elective Knee Arthroplasty

Evidence is mixed for an association between serum insulin-like growth factor-I (IGF-I) levels and postoperative delirium (POD). The current study assessed preoperative serum IGF-I levels as a predictor of incident delirium in non-demented elderly elective knee arthroplasty patients. Preoperative serum levels of total IGF-I were measured using a commercially available Human IGF-I ELISA kit. POD incidence and severity were determined using DSM-IV criteria and the Delirium Rating Scale-Revised-98 (DRS-R98), respectively. Median IGF-I levels in delirious (62.6 ng/ml) and non-delirious groups (65.9 ng/ml) were not significantly different (p = 0.141). The ratio (95% CI) of geometric means, D/ND, was 0.86 (0.70, 1.06). The Hodges-Lehmann median difference estimate was 7.23 ng/mL with 95% confidence interval (−2.32, 19.9). In multivariate logistic regression analysis IGF-I level was not a significant predictor of incident POD after correcting for medical comorbidities. IGF-I levels did not correlate with DRS-R98 scores for delirium severity. In conclusion, we report no evidence of association between serum IGF-I levels and incidence of POD, although the sample size was inadequate for a conclusive study. Further efforts to investigate IGF-I as a delirium risk factor in elderly should address comorbidities and confounders that influence IGF-I levels.

Effect of continuous positive airway pressure on insulin growth factor-1 in patients with obstructive sleep apnea: a meta-analysis

OBJECTIVE

Obstructive sleep apnea (OSA) has been recognized as being associated with low level of insulin growth factor-1 (IGF-1). However, the impact of OSA treatment using continuous positive airway pressure (CPAP) on IGF-1 remains controversial. We performed a meta-analysis to determine whether effective CPAP therapy could increase IGF-1 levels.

DESIGN

Two reviewers independently searched PubMed, Cochrane library, Embase and Web of Science before September 2014. Information on characteristics of subjects, study design and pre- and post-CPAP treatment of serum IGF-1 was extracted for analysis. Standardized mean difference (SMD) was used to analyze the summary estimates for CPAP therapy.

RESULTS

Six articles with 168 patients were included in this meta-analysis, including five observational studies and one randomized controlled study. The meta-analysis showed that CPAP was associated with a statistically significant increase in IGF-1 in OSA patients (SMD=-0.436, 95% confidence interval=-0.653 to -0.218, P=0.000).

CONCLUSIONS

This meta-analysis suggested that CPAP therapy was associated with an increase in IGF-1 in patients with OSA. Further large-scale, well-designed interventional investigations are needed to clarify this issue.

IGF-1: a potential biomarker for efficacy of sleep improvement with automatic airway pressure therapy for obstructive sleep apnea?

BACKGROUND

Positive airway pressure (PAP) reverses obstructive sleep apnea (OSA)-related hypoxia and restores slow wave sleep (SWS). Insulin-like growth factor 1 (IGF-1) is a neuropeptide that facilitates the repair of neurons from hypoxia and improves sleep regulation. IGF-1 concentrations are lower in OSA, and likely increase following PAP treatment; however, this relationship has not yet been determined in a younger cohort of OSA patients.

METHODS

This was a prospective, observational pilot study of 58 young men, who were diagnosed with OSA and provided PAP as an intervention. Adherence to PAP treatment over 3 months was objectively measured, as well as changes in the apnea-hypopnea index (AHI). Serum concentrations of IGF-1and C-reactive protein (CRP) were measured and correlated with PAP adherence.

RESULTS

IGF-1 concentrations at baseline were similar between PAP adherent 55.5 ± 34.4 ng/ml and PAP nonadherent participants 61.2 ± 27.1 ng/ml (p = 0.4), with the overall mean IGF-1 concentration of 59.0 ± 29.9 ng/ml. At follow-up, adherent participants had concentrations of IGF-1 that were significantly higher 128 ± 59.5 ng/ml compared to nonadherent participants 86.0 ± 47.4 ng/ml (p < 0.01). Increases in IGF-1 concentrations were significantly associated with reductions in AHI (Spearman's rho = -0.409, p = 0.015). Conversely, CRP concentrations did not differ between baseline and follow-up measurements in either group.

CONCLUSIONS

Adherence to PAP treatment leads to significant increases in IGF-1 concentrations in young men with OSA. While an objective measure of adherence exists, PAP usage does not allow for measure of sleep improvement. IGF-1 may serve as a potential biomarker for the efficacy of PAP therapy on improved sleep.

Sleep quality, BDNF genotype and gene expression in individuals with chronic abdominal pain

BACKGROUND

Sleep quality and genetics may contribute to the etiology of gastrointestinal (GI) symptoms. Individuals with impaired sleep often have a number of associated symptoms including chronic abdominal pain (CAP). The current study examined the interactions of brain-derived neurotrophic factor (BDNF) genotype with sleep quality in persons with CAP and healthy controls. In addition, associations among sleep quality, BDNF genotype, and gene expression were explored in the participants.

METHODS

Data were collected on 59 participants (46% male, 61% White, 26.9 ± 6.6 years; CAP (n=19) and healthy controls (n=40)). Participants with CAP reported poorer sleep quality compared to healthy controls. BDNF genotype, categorized as Val/Val homozygotes versus the Met carriers.

RESULTS

Microarray analysis found twenty-four differentially expressed genes by a two-fold magnitude in participants with poor sleep quality compared to good sleep quality, and seven differentially expressed genes comparing CAP to healthy control. Three specific genes in the pain group overlap with sleep quality, including insulin-like growth factor 1 (IGF1), spermatogenesis associated serine-rich 2-like (SPATS2L), and immunoglobulin heavy constant gamma 1 or mu (IGHG1/// IGHM). BDNF was shown to have an interaction effect with GI and sleep symptoms.

CONCLUSIONS

Participants with CAP reported poor sleep quality compared to healthy controls. The role of the BDNF Met allele on differential gene expression was not distinct as main factor, but impacted interactions with sleep quality and CAP. Down-regulation of IGF1, SPATS2L, and IGHG1 expression may be related to the etiology of poor sleep quality and CAP.

TRIAL REGISTRATION

Clinicaltrial.gov # NCT00824941.

Obstructive sleep apnea and delirium: exploring possible mechanisms

INTRODUCTION

Obstructive sleep apnea (OSA) is a medical disorder strongly associated with multiple comorbidities and postoperative complications. Current evidence suggests that OSA disturbs fundamental biochemical processes, leading to low-grade systemic inflammation and oxidative stress. Animal models have shown that OSA may lead to apoptosis of central neurons. In clinical studies, oxygen desaturation index and sleep fragmentation have been shown to be independently associated with cognitive dysfunction. Moreover, in several studies, patients with OSA were shown to have decreased brain activation in multiple brain areas.

OSA AND DELIRIUM

The possibility of an association between OSA and delirium has been highlighted in several case reports. The first prospective study of the possible link between apnea and delirium showed that the presence of OSA was independently associated with the occurrence of delirium after knee replacement surgery.

CONCLUSIONS

Therefore, we suggest that OSA should be considered as a risk factor for delirium, and clinicians should assess patients for OSA and related risk factors prior to surgery. However, further research is required to shed light on the mechanisms connecting these disorders and on whether the treatment of OSA affects the incidence of delirium.