Association between 25-Hydroxyvitamin D and Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis

Vitamin D deficiency: A forgotten aspect in sleep disorders? A critical update

Over the past few years, there has been a surge in interest regarding the connection between sleep duration and quality, sleep disorders, mainly Obstructive sleep apnoea (OSA) and Vitamin D. There is growing evidence to support a new role of Vitamin D in the maintenance and regulation of optimal sleep. Furthermore, a notable link has been identified between OSA and a decrease in serum Vitamin D levels, which appears to intensify as the severity of sleep apnea worsens. Vitamin D status could also potentially serve as a mediator or provide an explanation for the association between OSA and cardiometabolic morbidity, but the current state of research in this area is inadequate. Studies have indicated that the supplementation of Vitamin D can optimize sleep quality, presenting more proof of the connection between insufficient vitamin D levels and sleep disorders. However, it is unclear whether low serum Vitamin D levels are a contributing factor to OSA development or if OSA predisposes individuals to Vitamin D deficiency. As a result, various studies have endeavored to examine the complex relationship between OSA and Vitamin D deficiency. In children and adolescents, while data is limited, there seems also to be a link between sleep disorders and Vitamin D levels. Therefore, the objective of this review is to provide a comprehensive overview of the current evidence on the association between Vitamin D and sleep disorders in both adults and children.

Relationship of serum 25-hydroxyvitamin D, obesity with new-onset obstructive sleep apnea

OBJECTIVE

The prospective association between vitamin D and obstructive sleep apnea (OSA) remains uncertain. We aimed to assess the association between serum 25-hydroxyvitamin D (25(OH)D), a major circulating form of vitamin D, and new-onset OSA, and examine the modifying effect of obesity.

MATERIALS AND METHODS

This prospective cohort study included 444,975 participants from UK Biobank without prior OSA. The primary outcome was new-onset OSA.

RESULTS

During a median follow-up duration of 12.0 years, 6051 (1.4%) participants occurred new-onset OSA. Overall, there was an inverse relation of serum 25(OH)D concentrations with the risk of new-onset OSA (per SD increment, HR, 0.92; 95%CI: 0.89-0.95). In the analysis of the interactions of serum 25(OH)D with the combination of BMI (<25, 25- < 30, and ≥30 kg/m2) and waist circumference (WC) (<90 and ≥90 cm) categories on new-onset OSA, the significantly inverse association of serum 25(OH)D and new-onset OSA was mainly found in participants with both BMI ≥ 25 kg/m2 and WC ≥ 90 cm (BMI 25-30 kg/m2 and WC ≥ 90 cm: per SD increment, HR, 0.90; 95%CI: 0.84-0.95; BMI ≥ 30 kg/m2 and WC ≥ 90 cm: per SD increment, HR, 0.85; 95%CI: 0.81-0.88), but not in other four groups with BMI < 25 kg/m2 or WC < 90 cm (P -interaction = 0.004).

CONCLUSIONS

There was an inverse relation of serum 25(OH)D with the risk of new-onset OSA in participants with both BMI ≥ 25 kg/m2 and WC ≥ 90 cm. Our findings suggest the importance of maintaining a higher serum 25(OH)D concentration for primary prevention of OSA in a population with obesity.

Obstructive sleep apnea and vitamin D: an updated systematic review and meta-analysis

PURPOSE  : Obstructive sleep apnea (OSA) is a chronic, sleep-related breathing disorder which leads to increased cardiovascular risks. Vitamin D deficiency is associated with various cardiometabolic complications, including increased cardiovascular morbidity and mortality. We aimed to analyze the difference in serum 25-hydroxyvitamin D (25-OHD) level, prevalence of vitamin D insufficiency and deficiency, and the effect of CPAP treatment on serum 25-OHD levels among adult patients with OSA.

METHODS

We pooled data from 18 observational studies involving 5592 individuals. Baseline parameters that might have contributed to the significant differences observed were also analyzed.

RESULTS

Patients with OSA had significantly lower serum 25-OHD levels (pooled d +  - 0.74 [95% CI: - 1.19 to - 0.28], p < 0.01) and higher prevalence of vitamin D deficiency (pooled log (odds ratio) 0.98 [95% CI: 0.30 to 1.67], p < 0.01) compared to those without OSA. Subgroup analysis demonstrated that these differences were significant only in moderate OSA and severe OSA. Neither age nor BMI nor geographical latitude contributed significantly to the differences observed in serum 25-OHD levels. The use of CPAP did not lead to significant changes in serum 25-OHD levels.

CONCLUSION

Patients with OSA have lower serum 25-OHD levels with a higher prevalence of vitamin D deficiency, regardless of age or BMI, pointing to an independent association between vitamin D and OSA.

Serum vitamin D levels in patients with obstructive sleep apnea syndrome and level changes after continuous positive airway pressure therapy

PURPOSE

Patients with obstructive sleep apnea syndrome (OSAS) have been found to exhibit lower serum vitamin D levels, even when the control groups are matched for confounding conditions. However, contradictory studies are also present. This study aimed to compare serum 25-hydroxyvitamin D (25(OH)D) levels between adult patients with OSAS and non-apneic controls and to evaluate the changes in 25(OH)D levels after 3 and 12 months of continuous positive airway pressure (CPAP) therapy.

METHODS

The study was comprised of 30 patients with OSAS and 30 controls. Serum 25(OH)D levels were determined at baseline and after 3 and 12 months of CPAP therapy in all patients with OSAS. For analysis, patients with OSAS were divided into subgroups by adherence, with adherence defined as CPAP usage for > 4 h per night on at least 70% of nights.

RESULTS

The 25(OH)D levels were not significantly different between OSAS and control groups at baseline. 25(OH)D levels did not change after 3 and 12 months of CPAP therapy. Patients who were CPAP-adherent showed less reduction in 25(OH)D levels compared with non-adherent ones (21.18 ± 9.3 vs. 12.13 ± 3.8 ng/mL, p = 0.022) after 1 year. The 25(OH)D levels were significantly correlated with higher daily CPAP usage at 3 and 12 months. Mean daily CPAP usage was a significant predictor of serum 25(OH)D levels at 12 months.

CONCLUSIONS

Patients with OSAS who demonstrated good CPAP adherence showed significantly higher 25(OH)D levels after 1 year compared with those not adequately using CPAP. Long-term good CPAP adherence and highly daily CPAP usage positively affected 25(OH)D levels in patients with OSAS.

Vitamin D deficiency in patients evaluated for obstructive sleep apnea: is it associated with disease severity?

PURPOSE

The aim of the present study was to assess vitamin D levels in a large cohort of OSA patients and to investigate possible correlations with clinical and polysomnographic parameters.

METHODS

In this cross-sectional study, 685 consecutive patients underwent type 1 polysomnography (PSG) for OSA diagnosis. They were grouped according to apnea-hypopnea index (AHI) as mild, moderate, and severe. Patients with AHI < 5 served as controls. Demographic, PSG data, and serum levels of vitamin D were measured and compared between groups.

RESULTS

OSA was diagnosed in 617 of the patients (90%). Of those, 94 (15%) had mild OSA, 150 (24%) moderate OSA, and 373 (61%) severe OSA. The risk of vitamin D deficiency (< 20 ng/mL) was observed in 38% of the cohort. OSA patients had lower vitamin D levels compared to controls (23 ng/mL vs 26 ng/mL, p = 0.006). The lowest levels of vitamin D [mean 21] (p < 0.001 among all groups) and the higher prevalence for vitamin D deficiency (45%) were observed in severe OSA patients. After multiparametric adjustments for age, gender, obesity, and comorbidities, severe OSA showed significant independent associations with the risk of vitamin D deficiency [OR (95% CI) 2.002 (1.049-3.819), p = 0.035].

CONCLUSIONS

A large proportion of patients referred for OSA evaluation had vitamin D deficiency, which was independently associated with severe OSA. However, further research is needed in order to determine the role of vitamin D in OSA patients.

Serum vitamin D status does not correlate with the severity of obstructive sleep apnea in male adults: A controlled study design with minimized factors influencing serum vitamin D levels

Observational studies performed in homogeneous groups to objectively investigate the cause and effect relationship between vitamin D deficiency and sleep disorders are scarce. In this study, it was aimed to analyze the relationship between the severity of OSAS and vitamin-D levels among the participants whose features affecting serum vit-D levels were minimised. Serum 25-OH vitamin-D levels in 121 OSAS Male patients diagnosed by polysomnography without any systemic disease or vitamin-D supplement that may effect the vitamin-D metabolism were measured. The study was conducted in winter (latitude: 41°). Anthropometric measures and biochemical tests were also performed. The distribution of vitamin-D levels was determined as severe deficiency, deficiency, insufficiency and sufficiency. Apnea-hypopne index (AHI) < 5 was considered as a control group. Patients were categorized into four groups according to AHI as control, mild, moderate and severe. The groups were similar in terms of age, BMI, lipid profile, serum calcium, anthropometric measures and smoking. There was no significant difference in the distribution of vitamin-D levels between the patient and control groups and also within OSAS subgroups (p = 0.57, p = 0.86, respectively). Odds ratio to have OSAS in patients with vitamin-D deficiency was found as 0.745 (95 %CI: 0.33-1.7). Multinominal regression analysis showed no significant relationship between the OSAS severity and the extent of vitamin-D status. Correlation analysis showed no significant relationship between vitamin-D and AHI (r = 0.017, p = 0.877). Vitamin-D status does not alter the severity of OSAS. Vitamin-D deficiency might be the result of lifestyle changes due to OSAS rather than a cause.

The role of vitamin D in obstructive sleep apnoea syndrome

Obstructive sleep apnoea syndrome (OSAS) is a common disorder of multifactorial pathogenesis and is associated with obesity, diabetes and cardiovascular disease. Vitamin D is a fat-soluble vitamin with an important function in calcium absorption and homeostasis, which is also implicated in several nonskeletal conditions. The prevalence of vitamin D deficiency is increasing worldwide and is associated with similar metabolic disturbances to OSAS. Moreover, recent data suggest that in OSAS patients serum levels of vitamin D are lower compared with non-apnoeic subjects. However, the mechanisms linking vitamin D deficiency and OSAS are not completely understood and several hypotheses have been advanced. To date, a limited number of studies have assessed the association between lower serum concentrations of vitamin D and OSAS, and have reported inconsistent results. Similarly, contradictory results have been produced by studies which evaluated the effect of continuous positive airway pressure treatment on serum vitamin D levels. The aim of this review is to summarise current knowledge on the association between OSAS and vitamin D levels.

Due to multiple confounding factors, vitamin D deficiency is common among sleep apnoea patients; thus, screening should be performed when clinically indicatedhttp://ow.ly/L3ow30krmol

Obstructive sleep apnea and objective short sleep duration are independently associated with the risk of serum vitamin D deficiency

BACKGROUND

Studies demonstrate an association between vitamin D (25(OH)D) deficiency and sleep disturbances, such as obstructive sleep apnea (OSA) and short sleep duration. However, to date, no studies have concurrently and objectively evaluated the effect of these factors on 25(OH)D.

OBJECTIVES

To evaluate whether OSA and objective short sleep duration are independently associated with reduced 25(OH)D in an adult population sample.

METHODS

A cross-sectional study included 657 individuals from the city of Sao Paulo, Brazil, as part of the ERA project. Participants fulfilled questionnaires and underwent clinical evaluation, polysomnography and blood sample collection for 25(OH)D quantification. OSA was classified into three categories (mild, moderate and severe). The risk of 25(OH)D deficiency was considered as levels<30 ng/mL. Short sleep duration was defined as total sleep time<6 hours.

RESULTS

The risk of 25(OH)D deficiency was observed in 59.5% of the sample, affecting more individuals of the female gender, obese, with African American ethnicity, and those that were smokers, sedentary and presented hypertension and diabetes. In the final logistic model adjusted for age, gender, ethnicity, obesity, smoking, hypertension, diabetes, sedentary lifestyle, seasonality and creatinine serum levels, both OSA and short sleep duration showed significant independent associations with the risk of 25(OH)D deficiency (moderate OSA: OR for 25(OH)D<30 = 2.21, 95% CI: 1.35-3.64, p<0.01; severe OSA: OR for 25(OH)D<30 = 1.78, 95% CI: 1.06-3.00, p = 0.03; short sleep duration: OR for 25(OH)D<30 = 1.61, 95% CI: 1.15-2.26, p = 0.01). After a subgroup analysis, similar results were observed only in participants ≥50 years.

CONCLUSION

OSA and short sleep duration are independently associated with the risk of 25(OH)D deficiency in an adult population. Age-related changes in vitamin D metabolism and the frequency of sleep disorders may be involved in these associations. Future studies exploring whether 25(OH)D levels may modulate OSA and sleep curtailment-related outcomes are needed.