Sleep duration as an independent factor associated with vitamin D levels in the EPISONO cohort

Effect of CPAP therapy on vitamin D status in patients with obstructive sleep apnea and chronic obstructive pulmonary disease overlap syndrome

PURPOSE

Vitamin D (Vit D) deficiency has been associated with both obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) as well as with their combination, known as overlap syndrome (OS). There is evidence that continuous positive airway pressure (CPAP) may lead to an increase of Vit D levels in OSA patients. However, the effect of CPAP treatment on Vit D levels in OS patients has yet to be determined. The aim of the present study was to investigate the effect of one year of CPAP therapy on Vit D levels in patients with OS.

METHODS

Vit D serum levels were measured in consecutive OS patients at baseline and after one year of CPAP therapy. Compliance with CPAP therapy was assessed by the data retrieved from the CPAP device.

RESULTS

Vit D serum levels were measured in 46 OS patients (43 males). Among participants, 27 had good and 19 poor compliance with CPAP therapy. Results showed that serum Vit D levels increased after 12 months of CPAP therapy from 21.3 ± 8.4 to 23.8 ± 8.7 ng/ml (p = 0.001). Moreover, patients with good CPAP compliance demonstrated higher serum 25(OH)D levels compared to those with poor compliance (25.8 ± 7.6 versus 20.4 ± 9.6 ng/ml, respectively; p = 0.038).

CONCLUSIONS

In conclusion, 12 months of CPAP therapy improved Vit D serum levels in OS patients, more so in compliant patients.

Do not sleep on vitamin D: vitamin D is associated with sleep variability in apparently healthy adults

Vitamin D is associated with sleep quality and duration, but it is unclear whether vitamin D status influences sleep variability. Therefore, we sought to determine whether vitamin D status was associated with sleep variability in healthy adults. We assessed objective sleep, including timing and duration standard deviation (SD) using the Philips Actiwatch Spectrum and subjective sleep quality using the Pittsburgh Sleep Quality Index (PSQI) in 130 adults. We measured plasma 25(OH)D concentration to assess vitamin D. We used one-way ANOVAs and Kruskal-Wallis tests to compare sleep in participants characterized as vitamin D deficient (<20 ng/mL), insufficient (21-29 ng/mL), and sufficient (>30ng/mL). We used covariate-adjusted linear regression to assess associations between vitamin D status and sleep metrics. We compared differences in "low" and "high" sleep variability based on vitamin D status using the Chi-squared test. There was an effect of vitamin D status on sleep timing SD (Kruskal-Wallis, P = 0.021) and sleep duration SD (Kruskal-Wallis, P < 0.001). There was an inverse association between vitamin D status with sleep duration SD (after covariate adjustment R2 = 0.267, P < 0.001, deficient vs. sufficient P = 0.050, insufficient vs. sufficient P = 0.022). There was no effect of vitamin D status on objective sleep duration, efficiency, or PSQI scores (P > 0.05). We did not observe differences in "low" and "high" sleep timing SD based on vitamin D status (χ2 = 5.43, P = 0.066), but we did for sleep duration SD (χ2 = 22.4, P < 0.001). Our data indicate that individuals with poor vitamin D status exhibit greater objective sleep variability. Clinical Trial Registry: https://www.clinicaltrials.gov/; Unique identifiers NCT04334135, NCT04244604, and NCT04576338.NEW & NOTEWORTHY Our findings reveal that individuals with lower circulating vitamin D concentrations experience greater sleep variability compared with those with higher circulating concentrations. This supports the growing body of evidence suggesting an important link between vitamin D status and sleep health.

Roles of vitamins and nutrition in obstructive sleep apnea

INTRODUCTION

Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder, with a prevalence that rises alongside with the increasing prevalence of obesity. OSA is characterized by a low-inflammatory state and is followed by cardiovascular and metabolic sequelae. Continuous positive airway pressure (CPAP) represents the cornerstone of treatment for severe OSA. However, poor compliance with CPAP treatment renders OSA treatment a challenging venture. Weight loss and exercise are recommended as adjunctive treatment options for OSA. Several diets have proven to facilitate weight loss, and to alleviate the inflammatory status in patients with OSA. Moreover, several vitamins exhibit antioxidant properties that beneficially affect OSA pathology and reduce the risk of cardiovascular complications.

AREA COVERED

This narrative review aims to summarize the current knowledge regarding the effect of nutrition and vitamin deficiencies on OSA. Included were publications, relevant to the topic, with different types of design (i.e. cross-sectional studies, cohort studies, clinical trials, systematic reviews, meta-analyses, etc.) and indexed in PubMed database until 31 March 2024.

EXPERT OPINION

In addition to weight loss, other food components, such as proteins, carbohydrates, anti-inflammatory agents, vitamins A, B, C, D, E, and sodium, may play a beneficial role in the incidence and severity of OSA.

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.

Obstructive sleep apnea and vitamin D level: Has the dust settled?

Obstructive sleep apnea and vitamin D deficiency are associated with multiple complications with increased morbidity and mortality. However, the relationship between these two entities remains unclear, with clinical studies demonstrating contradictory results. This narrative review aims to present the current evidence and understanding of this relationship and discuss the possible mechanisms linking these two disease entities. Finally, we summarize and propose areas of opportunity for future research.

Sleep Patterns Modify the Association between Vitamin D Status and Coronary Heart Disease: Results from NHANES 2005-2008

BACKGROUND

Although an increased risk of coronary heart disease (CHD) has been reported in individuals with low vitamin D status, this remains controversial. Growing evidence suggests that sleep behaviors may influence vitamin D endocrine functions.

OBJECTIVES

We explored the association between serum 25-hydroxyvitamin D [[25(OH)D] concentrations and CHD and whether sleep behaviors modify this relationship.

METHODS

A cross-sectional analysis of 7511 adults aged ≥20 y in 2005-2008 National Health and Nutrition Examination Survey (NHANES) that included serum 25(OH)D concentrations and provided information on sleep behaviors and history of CHD was performed. Logistic regression models were used to assess the association between serum 25(OH)D concentrations and CHD, whereas stratified analyses and multiplicative interaction tests were used to evaluate the modification effect of overall sleep patterns and each sleep factor on this relationship. The overall sleep patterns integrated 4 sleep behaviors (sleep duration, snoring, insomnia, and daytime sleepiness) in the form of healthy sleep score.

RESULTS

Serum 25(OH)D concentrations were inversely associated with risk of CHD (P < 0.01). Hypovitaminosis D [serum 25(OH)D <50nmol/L] was associated with a 71% increased risk of CHD (OR: 1.71; 95% CI: 1.28, 2.28; P < 0.01) compared with that in participants with sufficient vitamin D [serum 25(OH)D ≥75nmol/L], and the association was more evident and stable among participants with poor sleep patterns (P-interaction < 0.01). Among the individual sleep behaviors, sleep duration had the strongest interaction with 25(OH)D (P-interaction < 0.05). The association between serum 25(OH)D concentrations and risk of CHD was more pronounced in participants with sleep duration <7 h/d or >8 h/d compared with those with sleep duration 7-8 h/d.

CONCLUSIONS

These findings suggest that the influence of lifestyle-related behavioral risk factors, such as sleep behaviors (especially sleep duration), need to be considered when evaluating the association between serum 25(OH)D concentrations and CHD as well as the clinical benefits of vitamin D supplementation.

Nocturnal sleep duration and bone mineral density: a cross-sectional study of the National Health and Nutrition Examination Survey (NHANES) 2007-2014

BACKGROUND

This study aimed to investigate the association between sleep duration and bone mineral density (BMD) and determine whether vitamin D (VD) status influenced the association between sleep duration and BMD.

METHODS

National Health and Nutrition Examination Survey 2007-2014 participants aged ≥ 40 years were included in this study. BMD testing was conducted with dual-energy X-ray absorptiometry examinations. Moreover, all individuals were divided into four groups according to self-reported nocturnal sleep duration (7-8 h; 6 h; < 6 h; and > 8 h). In addition, the differences in BMD between the normal sleep duration group and other groups were calculated using multiple linear regression models.

RESULTS

Overall, the median age of the overall study population was 55.00 years old, with 46.97% of men distributed. Participants sleeping > 8 h/night had lower BMDs than those sleeping 7-8 h/night. Moreover, the association between unhealthy sleep duration (especially > 8 h/night) and low BMD was more pronounced in older individuals, men, postmenopausal women, and subjects with inadequate VD intakes (< 15.00 µg/day) or deficient/insufficient serum 25-hydroxyvitamin D (< 75.00 nmol/L).

CONCLUSIONS

In conclusion, unhealthy sleep duration, especially long sleep duration, was associated with decreased BMD, particularly among individuals aged > 60 years, men, or postmenopausal women. Moreover, VD status might influence the association between sleep duration and BMD, especially in the context of inadequate VD intake or deficient/insufficient serum 25-hydroxyvitamin D levels. However, given the limitations of the present study, further investigation is warranted to confirm this association and to explore potential mechanisms.

Poor sleep quality, vitamin D deficiency and depression in the stroke population: A cohort study

BACKGROUND

Depression is a common psychiatric complication after stroke. However, the relationships among sleep quality, vitamin D status and depression are unclear in stroke patients. The aim of this study was to explore the impact of poor sleep quality and vitamin D status on post-stroke depression (PSD).

METHODS

In the present study, 233 stroke patients completed the one-month follow-up. Sleep quality was measured by the Pittsburgh Sleep Quality Index (PSQI) both at admission and 1 month after stroke. Depressive symptom was measured by the Hamilton Depression Scale (HAMD) at 1 month after stroke. Serum vitamin D levels were measured at admission. Multivariable logistic regression and mediation analysis were used to examine the mediating and moderating effects of sleep quality and vitamin D status on PSD.

RESULTS

The incidence of PSD was higher in patients with poor sleep quality than those with good sleep quality. Vitamin D levels were negatively correlated with HAMD score (r = -0.244, P < 0.001). Prestroke poor sleep quality was associated with an increased risk of PSD in the vitamin D deficiency group after adjustment for potential confounders (OR = 4.047, 95%CI = 1.300-12.600, P = 0.016), while this association was not significant in the vitamin D sufficiency group. In mediation analysis, the relationship between vitamin D deficiency and PSD was mediated by poststroke sleep quality.

LIMITATIONS

Vitamin D levels were measured only at admission.

CONCLUSIONS

The combination of poor sleep quality and vitamin D deficiency is associated with a substantially increased risk of PSD.