Respiratory symptoms are more common among short sleepers independent of obesity. Björnsdóttir Erla,Janson Christer,Lindberg Eva,Arnardottir Erna Sif,Benediktsdóttir Bryndís,Garcia-Aymerich Judith,Carsin Anne Elie,Real Francisco Gómez,Torén Kjell,Heinrich Joachim,Nowak Dennis,Sánchez-Ramos José Luis,Demoly Pascal,Arenas Sandra Dorado,Navarro Ramon Coloma,Schlünssen Vivi,Raherison Chantal,Jarvis Debbie L,Gislason Thorarinn BMJ open respiratory research INTRODUCTION:Sleep length has been associated with obesity and various adverse health outcomes. The possible association of sleep length and respiratory symptoms has not been previously described. The aim of this study was to investigate the association between sleep length and respiratory symptoms and whether such an association existed independent of obesity. METHODS:This is a multicentre, cross-sectional, population-based study performed in 23 centres in 10 different countries. Participants (n=5079, 52.3% males) were adults in the third follow-up of the European Community Respiratory Health Survey III. The mean±SD age was 54.2±7.1 (age range 39-67 years). Information was collected on general and respiratory health and sleep characteristics. RESULTS:The mean reported nighttime sleep duration was 6.9±1.0 hours. Short sleepers (<6 hours per night) were n=387 (7.6%) and long sleepers (≥9 hours per night) were n=271 (4.3%). Short sleepers were significantly more likely to report all respiratory symptoms (wheezing, waking up with chest tightness, shortness of breath, coughing, phlegm and bronchitis) except asthma after adjusting for age, gender, body mass index (BMI), centre, marital status, exercise and smoking. Excluding BMI from the model covariates did not affect the results. Short sleep was related to 11 out of 16 respiratory and nasal symptoms among subjects with BMI ≥30 and 9 out of 16 symptoms among subjects with BMI <30. Much fewer symptoms were related to long sleep, both for subjects with BMI <30 and ≥30. CONCLUSIONS:Our results show that short sleep duration is associated with many common respiratory symptoms, and this relationship is independent of obesity. 10.1136/bmjresp-2017-000206

Association between depressive symptoms and lung function in the United States adults without pulmonary diseases: A cross-sectional study from NHANES. Journal of affective disorders BACKGROUND:Depression is a severe and common mental disorder. The association between depressive symptoms and lung function remains unclear. To determine whether depressive symptoms are associated with lung function in U.S. adults without pulmonary diseases. METHODS:A cross-sectional study of National Health and Nutrition Examination Survey (NHANES) data from 2007 to 2012 were used to estimate the relationship between depressive symptoms and lung function. Depressive symptoms were determined by a participant's score on the Patient Health Questionnaire-9. Forced Expiratory Volume 1st Second (FEV1) Forced Vital Capacity (FVC) were determined by the spirometry. Weighted multivariate linear regression was used to analyze this relationship and subgroup analyses were performed. RESULTS:Of 8027 participants, 576 (7.18 %) participants with depression. Depression group had significant lower FEV1 and FVC than non-depression group. After adjustment for all covariates, there was a significant negative association between depressive symptoms and FVC (β -4.84, 95 % CI -9.10 to -0.57), especially in non-Hispanic White people (β -9.03, 95 % CI -14.38 to -3.69). There was no independent association between depressive symptoms and FEV1 in all participants, whereas the association was significant in non-Hispanic White people (β -4.91, 95 % CI -9.50 to -0.32). CONCLUSIONS:High depressive symptoms were independently associated with decline of FVC among U.S. adults without pulmonary diseases, especially in non-Hispanic White people. In addition, although it was not independently associated with FEV1 in all participants, depressive symptom score was also negatively associated with FEV1 in non-Hispanic White people. 10.1016/j.jad.2022.12.110

Correlation between serum iron levels and pulmonary function: A cross-sectional analysis based on NHANES database 5319 cases. Medicine Pulmonary function, one of the main indicators of respiratory system assessment, is difficult to measure in specific cases. The study investigated the association between serum iron levels and pulmonary function. The cross-sectional study was conducted using data from 5319 participants from the 2010-2012 National Health and Nutrition Examination Survey. Forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and forced expiratory flow from 25% to 75% of FVC were used as indicators of pulmonary function to analyze the relationship of serum iron and pulmonary function. Univariate and stratified analyses, multiple equation regression analysis, smoothed curve fitting analysis, and threshold effect analysis were performed to explore the relationship between pulmonary function and serum iron concentrations. Threshold effect analysis revealed a nonlinear relationship between serum iron levels and FVC, as well as FEV1, with inflection points observed at 8.1 (µmol/L) and 8.4 (µmol/L), respectively. When serum iron concentrations fell below the inflection point, there was no statistically significant relationship between serum iron and FVC (P = .065) or FEV1 (P = .095) (P > .005). However, when serum iron concentrations exceeded the inflection point, both FVC (β = 6.87; 95% confidence interval [CI] = 3.95, 9.79; P < .0001) and FEV1 (β = 7.09; 95% CI = 4.54, 9.64; P < .0001) exhibited a positive correlation with increasing serum iron levels. Additionally, forced expiratory flow from 25% to 75% of FVC (mL/s) demonstrated a positive association with serum iron (β = 6.72; 95% CI = 2.30, 11.13; P = .0029). Serum iron level was positively correlated with pulmonary function within a certain range of serum iron concentration. Serum iron level may be a protective factor for pulmonary function. 10.1097/MD.0000000000036449

Non-linear association between diabetes mellitus and pulmonary function: a population-based study. Zhang Rui-Heng,Zhou Jian-Bo,Cai Yao-Hua,Shu Lin-Ping,Simó Rafael,Lecube Albert Respiratory research BACKGROUND:There is increasing evidence that the lung is a target organ of diabetes. This study aimed to examine in detail the association between diabetes mellitus and pulmonary function using a national cohort. We also aimed to explore the non-linear association between pulmonary function and blood glucose, insulin resistance, and C-reactive protein (CRP). METHODS:A total of 30,442 participants from the National Health and Nutrition Examination Survey from the period between 2007 and 2012 were included. The cross-sectional association between diabetes mellitus and pulmonary function was assessed using multiple linear regression. Where there was evidence of non-linearity, we applied a restricted cubic spline with three knots to explore the non-linear association. Partial mediation analysis was performed to evaluate the underlying mechanism. All analyses were weighted to represent the US population and to account for the intricate survey design. RESULTS:A total of 8584 people were included in the final study population. We found that diabetes was significantly associated with reduced forced expiratory volume in one second (FEV) and forced vital capacity. We further found L-shaped associations between hemoglobin A1c (HbA1c) and pulmonary function. There was a negative association between HbA1c and FEV in diabetes participants with good glucose control (HbA1c < 7.0%), but not in patients with poor glucose control. A non-linear association was also found with fasting plasma glucose, 2 h-plasma glucose after oral glucose tolerance test, insulin resistance, and CRP. Finally, we found that diabetes duration did not affect pulmonary function, and the deleterious effect of diabetes on pulmonary function was mediated by hyperglycemia, insulin resistance, low-grade chronic inflammation (CRP), and obesity. CONCLUSIONS:Diabetes mellitus is non-linearly associated with pulmonary function. Our finding of a negative association between HbA1c and FEV in diabetes patients with good glucose control but not in patients with poor glucose control indicates that a stricter glycemic target should be applied to diabetic patients to improve pulmonary function. Given, the cross-sectional nature of this research, a longitudinal study is still needed to validate our findings. 10.1186/s12931-020-01538-2