No Associations Between Serum Lipid Levels or HOMA-IR and Asthma in Children and Adolescents: A NHANES Analysis

Associations between hypovitaminosis D, adiposity indices and insulin resistance in adolescents: mediation analyses from NHANES 2011-2018

BACKGROUND

As all kown, both hypovitaminosis D and insulin resistance (IR) have been linked to adiposity. However, the extent of adiposity's mediating influence on the hypovitaminosis D-IR relationship among adolescents remains to be elucidated. Additionally, the intricate effects of obesity and blood lipid profiles on IR are not yet fully understood.

METHODS

We conducted a comprehensive analysis of NHANES data from 2011 to 2018, examining the correlation between adiposity indices such as Body Mass Index (BMI), Fat Mass Index (FMI, defined as the ratio of fat mass to height squared), hypovitaminosis D, and IR. We employed the XGBoost algorithm to identify key factors significantly influencing IR, thereby deepening our insight into the link between adiposity and insulin resistance. Furthermore, we applied mediation analysis to precisely assess the mediating role of adiposity indices in the relationship between hypovitaminosis D and IR.

RESULTS

Our study revealing significant correlations between adiposity indices, hypovitaminosis D, and IR after variable adjustment. Notably, subgroup analysis indicated a pronounced hypovitaminosis D -adiposity association in female adolescents, which was not observed in males. The XGBoost algorithm pinpointed obesity and blood lipid indicators significantly affecting IR, with total fat mass, triglyceride, cholesterol, BMI, and FMI ranked by descending importance. Mediation analysis disclosed that adiposity indices mediate a substantial portion of the hypovitaminosis D -IR relationship, with FMI (43.84%, p < 0.001) and BMI (40.87%, p < 0.001) showing significant mediating effects.

CONCLUSION

The study confirmed significant correlations between adiposity indices, hypovitaminosis D, and IR in adolescents, with gender-specific differences in the hypovitaminosis D -adiposity link. Cholesterol was found to have a more substantial influence on IR than BMI and FMI. Furthermore, FMI was identified as a more potent mediator of the hypovitaminosis D-IR relationship compared to BMI, highlighting its importance in the pathophysiology of insulin resistance in adolescents.

Effect of polyunsaturated fatty acids intake on the occurrence of current asthma among children and adolescents exposed to tobacco smoke: NHANES 2007-2018

BACKGROUND

Asthma is an airway inflammatory disease driven by multiple factors with a high incidence in children and adolescents. Environmental tobacco smoke exposure (TSE) and diet are inducing factors for asthma. The potential of omega-3 polyunsaturated fatty acids (PUFAs) to alleviate asthma symptoms by their anti-inflammatory effects has been explored. However, to date, no studies have explored the effect of dietary PUFAs intake on the asthma in children and adolescents exposed to tobacco smoke.

OBJECTIVE

We aimed to examine the effect of dietary PUFAs intake on the current asthma in children and adolescents exposed to tobacco smoke.

METHODS

Data of this cross-sectional were extracted from the National Health and Nutrition Examination Survey (NHANES) 2007-2018. Children and adolescents with serum cotinine concentration ≥ 0.05 ng/mL were defined to exposed to tobacco smoke. Dietary PUFAs intake information were obtained from 24 h recall interview. The weighted univariate and multivariate were utilized to explore the effect of PUFAs on the association of asthma and TSE, with adjusted odds ratios (AORs) and 95% confidence intervals (CIs). These moderating effects were further explored based on the age, gender and body mass index (BMI) and sedentary time.

RESULTS

Totally, 7981 eligible children and adolescents were included, with the mean age of 11.96 ± 0.06 years old. Of whom, 1.024 (12.83%) had current asthma. After adjusted all covariates, we found children and adolescents with TSE had high occurrence of current asthma (AOR = 1.2, 95% CI 1.03-1.63); We also found omega-3 PUFAs intake (P for interaction = 0.010), not omega-6 PUFAs (P for interaction = 0.546), has a moderating effect on the association of TSE and current asthma. Moreover, we further observed that children and adolescents with TSE and low omega-3 PUFAs intake had high occurrence of current asthma (AOR = 1.58, 95% CI 1.19-2.10), while no significant association was found in children and adolescents with high omega-3 PUFAs intake (all P > 0.05). This moderating effect was more prominent in children and adolescents aged ≤ 12 years old (AOR = 1.62, 95% CI 1.06-2.47), girls (AOR = 2.14, 95% CI 1.15-3.98), overweight (AOR = 1.87, 95% CI 1.01-3.47) and sedentary time > 6 h (AOR = 1.96, 95% CI 1.00-3.86).

CONCLUSION

We found dietary omega-3 PUFAs plays a moderating effect on the association of asthma and TSE in children and adolescents, especially in children and adolescents aged ≤ 12 years, girls, overweight or sedentary time > 6 h. This moderating effect suggested higher omega-3 intake has potential benefits in decreasing the occurrence of asthma in children and adolescents who exposed to tobacco smoke.

Association of blood lipid profiles and asthma: A bidirectional two-sample Mendelian randomization study

BACKGROUND

Observational studies and meta-analyses have indicated associations between blood lipid profiles and asthma. However, the causal association is unknown. Therefore, this study investigated the causal relationship between blood lipid profiles and asthma using bidirectional Mendelian randomization analysis.

METHODS AND MATERIALS

Our analyses were performed using individual data from the Taiwan Biobank and summary statistics from the Asian Genetic Epidemiology Network (AGEN). The causal estimates between all genetic variants, exposures of interest and asthma were calculated using an inverse-variance weighted method based on Taiwan Biobank data from 24,853 participants (mean age, 48.8 years; 49.8% women). Sensitivity analyses, including the weighted median, MR Egger regression, MR-PRESSO, mode-based estimate, contamination mixture methods, and leave-one-out analysis, were applied to validate the results and detect pleiotropy.

RESULTS

In the inverse-variance weighted (IVW) analyses, we found evidence of a significant causal effect of an increased level of low-density lipoprotein cholesterol on asthma risk (βIVW = 1.338, p = 0.001). A genetically decreased level of high-density lipoprotein cholesterol was also associated with asthma risk (βIVW = -0.338, p = 0.01). We also found that an increased level of total cholesterol was associated with an increased risk of asthma (βIVW = 1.343, p = 0.001). Several sensitivity analyses generated consistent findings. We did not find evidence to support the causality between asthma and blood lipid profiles in either direction.

CONCLUSION

Our results supported the causal relationship between higher levels of LDL cholesterol and total cholesterol and lower levels of HDL cholesterol with an increased risk of asthma.

[Relationship between atherogenic index of plasma and childhood asthma]

OBJECTIVES

To explore the relationship between atherogenic index of plasma (AIP) and childhood asthma.

METHODS

This retrospective study included 86 children with asthma admitted to the Changzhou Second People's Hospital Affiliated to Nanjing Medical University from July 2020 to August 2022 as the asthma group and 149 healthy children undergoing physical examination during the same period as the control group. Metabolic parameters including total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and blood glucose, as well as general information of the children such as height, weight, body mass index, presence of specific dermatitis, history of inhalant allergen hypersensitivity, family history of asthma, and feeding history, were collected. Multivariable logistic regression analysis was used to study the relationship between AIP, triglycerides, and high-density lipoprotein cholesterol and asthma. The value of AIP, triglycerides, and high-density lipoprotein cholesterol for predicting asthma was assessed using receiver operating characteristic (ROC) curve analysis.

RESULTS

The AIP and triglyceride levels in the asthma group were significantly higher than those in the control group, while high-density lipoprotein cholesterol was significantly lower (P<0.05). However, there was no significant difference in total cholesterol and low-density lipoprotein cholesterol between the two groups (P>0.05). Before and after adjusting for height, weight, presence of specific dermatitis, history of inhalant allergen hypersensitivity, family history of asthma, feeding method, and blood glucose, multivariable logistic regression analysis showed that AIP, triglycerides, and high-density lipoprotein cholesterol were associated with asthma (P<0.05). ROC curve analysis showed that the optimal cutoff value for predicting asthma with AIP was -0.333, with a sensitivity of 80.2%, specificity of 55.0%, positive predictive value of 50.71%, and negative predictive value of 82.85%. The area under the curve (AUC) for AIP in predicting asthma was significantly higher than that for triglycerides (P=0.009), but there was no significant difference in AUC between AIP and high-density lipoprotein cholesterol (P=0.686).

CONCLUSIONS

AIP, triglycerides, and high-density lipoprotein cholesterol are all associated with asthma. AIP has a higher value for predicting asthma than triglycerides and comparable value to high-density lipoprotein cholesterol.

Association Between Atopic Dermatitis, Asthma, and Serum Lipids: A UK Biobank Based Observational Study and Mendelian Randomization Analysis

Background

Both atopic diseases and dysregulation of serum lipids (SLs) add to significant health burden, but evidences about their association are inconsistent.

Objective

This work is to evaluate the association between asthma/atopic dermatitis (AD) and SLs and investigate the potential causal relationship.

Methods

A large-scale cross-sectional study based on the UK Biobank (UKB) and then examined the casual relationships between SLs with asthma/AD based on a Mendelian randomization (MR) analysis.

Results

A total of 502,505 participants were included in analysis. After full adjustment, AD was associated with lower TG (β = −0.006; 95%CI, −0.010 to −0.002; P = 0.006), lower LDL (β = −0.004; 95%CI, −0.006 to −0.002, P < 0.001), and lower TC (β = −0.004; 95%CI, −0.005 to −0.002; P < 0.001) but insignificantly correlated to HDL (P = 0.794). Asthma was also inversely correlated to TG (β = −0.005; 95%CI, = −0.007 to −0.003; < 0.001), LDL (β = −0.003; 95%CI, −0.004 to −0.002; P < 0.001), and TC (β = −0.002; 95%CI, −0.003 to −0.002; P < 0.001), but was positively correlated to HDL (β = 0.004; 95%CI, 0.003 to 0.005; P < 0.001), respectively. In subsequent MR analysis, both allergic diseases and asthma showed a protective effect on TC. Allergic diseases, asthma, and AD all showed a negative effect on LDL.

Conclusion

Collectively, we identify a protective causal effect of allergic diseases on serum lipids, as well as a potentially positive association of HDL with asthma. Owing to the largest sample size and the application of IVs in causal inference, this study will provide a robust evidence for the management of asthma and AD and the prevention of dyslipidemia.

A new perspective on cholesterol in pediatric health: association of vitamin D metabolism, respiratory diseases, and mental health problems

Cholesterol, the main structural molecule of cell membranes, is involved in essential functions of the human body. Dyslipidemia is an established risk factor for cardiovascular diseases (CVDs) that is observed even in childhood. To reduce the risk of CVDs in children, several clinical guidelines have been published for the management of pediatric dyslipidemia. However, pediatric dyslipidemia is also associated with several health problems other than CVDs. This article reviews the current data on dyslipidemia-related pediatric health issues. There is strong evidence that low serum vitamin D levels, asthma, and mental health problems may be associated with dyslipidemia in the pediatric population regardless of body mass index. This review also highlights the need for further large-scale population-based studies in the Korean pediatric population to establish effective strategies for promoting children's health.

Association of Dyslipidemia and Respiratory Resistance Assessed by the Forced Oscillation Technique in Asthmatic Children

PURPOSE

This study aimed to evaluate the associations between dyslipidemia and pulmonary function parameters assessed by spirometry and the forced oscillation technique in asthmatic children.

METHODS

Asthmatic children (5-18 years old) had fasting serum lipid profiles including low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride (TG), and high-density lipoprotein cholesterol (HDL-C) concentrations, and C-reactive protein (CRP) measured. Pulmonary function tests were assessed by spirometry and the forced oscillation technique (FOT).

RESULTS

One hundred forty-one asthmatic children were enrolled with a mean (SD) age of 11.82 (3.38) years. Eighty-eight (62.4%) children were boys, 64 (45.4%) had dyslipidemia, and 20 (14.2%) were obese. Among the children with dyslipidemia, a high LDL-C concentration (65.6%) was the most common form of dyslipidemia, followed by high TC (57.8%), high TG (35.9%), and low HDL-C concentrations (15.6%). Multivariable analysis showed significant associations between HDL-C concentrations and respiratory resistance at 5 Hz (R₅) and respiratory resistance at 20 Hz (R₂₀), and TC concentrations were modestly associated with reactance at 5 Hz (X₅), the frequency of resonance (Fres), and the area of reactance (ALX). Asthmatic children who had high LDL-C concentrations had a significantly higher expiratory phase R₅, whole breath R₂₀, and expiratory phase R₂₀ than those in children with normal LDL-C concentrations.

CONCLUSION

This study suggests an association of blood cholesterol, especially HDL-C and LDL-C, and respiratory resistance measured by the FOT, irrespective of the obesity status. An intervention for improving LDL-C and HDL-C concentrations may be beneficial on lung function parameters in asthmatic children.

CLINICAL TRIAL REGISTRATION

TCTR20200305005; date of registration: 03-04-2020 (retrospectively registered).

Nutrition, Obesity and Asthma Inception in Children. The Role of Lung Function

Obesity is an important public health problem. WHO estimates that about 39 million children younger than 5 years of age are overweighted or obese. On the other hand, asthma is the most prevalent chronic disease in childhood, and thus, many children share those two conditions. In the present paper we review the epidemiology of children with asthma and obesity, as well as the consequences of being obese on the respiratory system. On the one hand obesity produces an underlying T-helper 2 (TH2) low inflammation state in which numerous cytokines, which could have an impact in the respiratory system play, a role. On the other hand, some respiratory changes have been described in obese children and, specially, the development of the so called “dysanapsis” (the disproportionate scaling of airway dimensions to lung volume) which seems to be common during the first stages of life, probably related to the early development of this condition. Finally, this review deals with the role of adipokines and insulin resistance in the inception and worsening of asthma in the obese child.

Association between elevated serum triglycerides and asthma in patients with obesity: An explorative study

Background: Adults with a high body mass index (BMI) have an increased risk of developing asthma. To explore the impact of increased lipids on the presence of asthma, this study investigated the relationship between lipid levels and inflammatory markers in patients with asthma and controls with obesity. Objective: We hypothesized that higher lipid levels are more prevalent in patients with obesity and asthma. Methods: In this explorative cohort study, 96 patients with asthma and 45 controls were included. All the patients participated in one of three asthma studies; two of these studies included only patients with obesity. An asthma diagnosis was defined by the presence of typical clinical symptoms, reversible airway obstruction (+12% improvement in forced expiratory volume in the first second of expiration after bronchodilator), or bronchial hyperreactivity (Histamine PC20 < 8 mg/mL), or a fractional exhaled nitric oxide of > 50 ppb. We compared lipid levels and neutrophils and eosinophils in patients with asthma and the controls with a wide BMI range (17.8-63.8 kg/m²). Multivariable logistic regression was used to analyze the data. Results: Serum triglycerides were statistically significantly higher in patients with obesity and asthma adjusted for BMI, blood eosinophils, and statin use (odds ratio [OR] 2.56 [95% confidence interval, 1.34-4.88]; p = 0.004). Inclusion or exclusion of those who used long-acting β2-agonists and inhaled corticosteroids led to comparable adjusted ORs for blood triglyceride and blood eosinophils levels. Conclusion: Elevated serum triglycerides were associated with the presence of asthma in patients with obesity. This indicated that elevated triglycerides might be a yet unrecognized trait that contributed to the development of asthma. The precise cause and effect of these high triglyceride levels in the patients with asthma and with obesity were not determined in this study.Clinical trial Trial registration NCT03278561, <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.clinicaltrials.gov">www.clinicaltrials.gov</ext-link>; NL4262, NL3056, trialregister.nl.

High-Density Lipoprotein (HDL) in Allergy and Skin Diseases: Focus on Immunomodulating Functions

From an evolutionary perspective, lipoproteins are not only lipid transporters, but they also have important functions in many aspects of immunity. High-density lipoprotein (HDL) particles are the most abundant lipoproteins and the most heterogeneous in terms of their composition, structure, and biological functions. Despite strong evidence that HDL potently influences the activity of several immune cells, the role of HDL in allergies and skin diseases is poorly understood. Alterations in HDL-cholesterol levels have been observed in allergic asthma, allergic rhinitis, atopic dermatitis (eczema), psoriasis, urticaria, and angioedema. HDL-associated apolipoprotein (apo) A-I, apoA-IV, and apoC-III, and lyso-phosphatidylcholines potently suppress immune cell effector responses. Interestingly, recent studies provided evidence that allergies and skin diseases significantly affect HDL composition, metabolism, and function, which, in turn, could have a significant impact on disease progression, but may also affect the risk of cardiovascular disease and infections. Interestingly, not only a loss in function, but also, sometimes, a gain in function of certain HDL properties is observed. The objective of this review article is to summarize the newly identified changes in the metabolism, composition, and function of HDL in allergies and skin diseases. We aim to highlight the possible pathophysiological consequences with a focus on HDL-mediated immunomodulatory activities.