Association between adiposity measures and COPD risk in Chinese adults

The Role of Active and Passive Smoking in Chronic Obstructive Pulmonary Disease and Systemic Inflammation: A 12-year Prospective Study in China

BACKGROUND

There is no consensus on the cause and effect of systemic chronic inflammation (SCI) regarding chronic obstructive pulmonary disease (COPD). The impact of second-hand smoke (SHS) on COPD has reached inconsistent conclusions.

METHODS

The China Kadoorie Biobank cohort was followed up from the 2004-08 baseline survey to 31 December 2018. Among the selected 445,523 participants in the final analysis, Cox and linear regressions were performed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of tobacco exposure with COPD risk and baseline levels of log-transformed inflammatory factors [βs (95% CIs)], respectively.

RESULTS

Participants were followed up for a median of 12.1 years and 11,825 incident COPD events were documented. Ever-smokers were associated with a higher risk of COPD than non-smokers with non-weekly SHS exposure. A younger age to start smoking, a greater amount of daily tobacco consumption, and deeper inhalation were associated with increased risk of COPD and correlated with elevated levels of plasma high-sensitivity C-reactive protein (hs-CRP, all Ptrend < 0.001) even two years before COPD onset. Among former smokers, COPD risk declined with longer smoking cessation (Ptrend < 0.001) and those quitting smoking for over ten years presented no difference in COPD risk and hs-CRP level from non-smokers [HR (95% CI) = 1.05 (0.89, 1.25), β (95% CI) = 0.17 (- 0.09, 0.43)]. Among non-smokers, weekly SHS exposure was associated with a slightly higher COPD risk [HR (95% CI) = 1.06 (1.01, 1.12)].

CONCLUSIONS

Incremental exposure to tobacco smoke was related to elevated SCI level before COPD onset, then an increase in COPD susceptibility. Quitting smoking as early as possible is suggested as a practical approach to reducing COPD risk in smokers. Given the high prevalence of both COPD and SHS exposure, the risk associated with SHS exposure deserves attention.

Trajectory Patterns of Macronutrient Intake and Their Associations with Obesity, Diabetes, and All-Cause Mortality: A Longitudinal Analysis over 25 Years

Over the past decades, China has been undergoing rapid economic growth, which may have significantly influenced the dietary patterns and health status of the Chinese population. Our study aimed to assess the associations of potential macronutrient trajectory patterns with chronic diseases and all-cause mortality using the latent class trajectory model (LCTM) and the longitudinal data of the China Health and Nutrition Survey obtained between 1991 and 2015. A 24-hour diet recall was used to assess the dietary intake. The Poisson regression model was employed to investigate the correlations between trajectory patterns and chronic diseases and all-cause mortality. A total of 8115 participants were included in the final analysis. We explored four and three trajectory patterns for male and female populations, respectively. We found that a decreasing very high-carbohydrate trajectory together with a U-shape protein trajectory was associated with a higher risk of diabetes in the male population (odds ratio (OR): 2.23; 95% confidence interval (CI): 1.31-3.77). A similar pattern for moderate protein intake was also associated with the risk of diabetes in the female population (OR: 1.82; 95% CI: 1.18-2.79). In addition, we show that a decreasing low-carbohydrate trajectory and an increasing high-fat trajectory were associated with a lower risk of all-cause mortality (OR: 0.76; 95% CI: 0.60-0.96) and a higher risk of obesity (OR: 1.24; 95% CI: 1.05-1.47) in males. Our results shed light on some salient nutritional problems in China, particularly the dual challenges of undernutrition and overnutrition.

Ageing and disease risk factors: A new paleoepidemiological methodology for understanding disease in the past

OBJECTIVES

To outline a methodology that enables the reconstruction of age-related disease risk in past societies.

MATERIALS

Modern epidemiological evidence considering risk factors for age-related disease is combined with contextual information about an archaeological society of interest.

METHODS

Data gathered is used to create a qualitative population-specific risk model for the disease of interest. To provide a case study, a risk model is constructed for Chronic Obstructive Pulmonary Disease (COPD) in the Eastern English Bronze Age.

RESULTS

This enables the first rigorous approach to reconstructing age-related disease risk in the past. A risk model shows a high degree of COPD risk in the Eastern English Bronze Age, with a major contribution from indoor airborne pollution and agricultural practices.

SIGNIFICANCE

This represents a significant new approach in human paleopathology, facilitating understanding of the occurrence of a wide variety of diseases in the past, without the need for well-preserved skeletons of identified elderly individuals.

LIMITATIONS

The risk models generated are, of necessity, qualitative rather than quantitative, since we are unable to calculate the size of risk factors in the past with certainty.

SUGGESTIONS FOR FURTHER RESEARCH

The methodology could be applied to a wide variety of diseases and for many past societies.

Metabolic syndrome, genetic susceptibility, and risk of chronic obstructive pulmonary disease: The UK Biobank Study

AIM

To investigate the effect of metabolic syndrome (MetS), genetic predisposition, and their interactions, on the risk of developing chronic obstructive pulmonary disease (COPD).

METHODS

Cohort analyses included 287 868 participants from the UK Biobank Study. A genetic risk score for COPD was created using 277 single nucleotide polymorphisms. Cox proportional hazard models were used to evaluate the hazard ratios (HRs) with 95% confidence intervals (CIs) for COPD in relation to exposure factors.

RESULTS

During 2 658 936 person-years of follow-up, 5877 incident cases of COPD were documented. Compared with participants without MetS, those with MetS had a higher risk of COPD (HR 1.24, 95% CI 1.17-1.32). Compared to participants with low genetic predisposition, those with high genetic predisposition had a 17% increased risk of COPD. In the joint analysis, compared with participants without MetS and low genetic predisposition, the HR for COPD for those with MetS and high genetic predisposition was 1.50 (95% CI 1.36-1.65; P < 0.001). However, no significant interaction between MetS and genetic risk was found.

CONCLUSIONS

Metabolic syndrome was found to be associated with an increased risk of COPD, regardless of genetic risk. It is crucial to conduct further randomized control trials to determine whether managing MetS and its individual components can potentially reduce the likelihood of developing COPD.

Waist to height ratio as a simple tool for predicting mortality: a systematic review and meta-analysis

BACKGROUND

The association of central obesity with higher rates of mortality is not well studied. This study evaluates the association between waist-to-height ratio (WHtR), as a measure of central obesity, with mortality.

METHODS

Documents were retrieved from PubMed, Web of Science, Scopus, and Google Scholar databases until May 2022. Data were extracted from cohort studies reporting effect size (hazard ratio (HR)) regarding the association between WHtR as a continuous (per 1 SD increment) or categorical (highest/lowest) measure and all-cause and cause-specific mortality. Screening of included studies was performed independently by two authors. Moreover, the quality assessment of included studies was performed based on the Newcastle-Ottawa assessment scale. Finally, random effect meta-analysis was performed to pool the data, and the outcomes' certainty level was assess based on the GRADE criteria.

RESULTS

Of the 815 initial studies, 20 were included in the meta-analysis. Random effect meta-analysis showed that in the general population, the all-cause mortality HRs for categorical and continuous measurements of WHtR increased significantly by 23% (HR:1.23; 95% CI: 1.04-1.41) and 16% (HR:1.16; 95% CI: 1.07-1.25), respectively. Moreover, the hazard of cardiovascular (CVD) mortality increased significantly for categorical and continuous measurements of WHtR by 39% (HR:1.39; 95% CI: 1.18-1.59) and 19% (HR:1.19; 95% CI: 1.07-1.31). The quality assessment score of all included studies was high.

CONCLUSIONS

Higher levels of WHtR, indicating central obesity, were associated with an increased hazard of CVD and all-cause mortality. This measure can be used in the clinical setting as a simple tool for predicting mortality.

Salt reduction behavior of adults in Anhui province in 2019: a cross-sectional survey of 3,378 participants

Objective

A high-sodium diet is an important risk factor for hypertension in the Chinese population, which can increase the risk of cardiovascular and cerebrovascular diseases. Although a large number of related studies have been carried out in Anhui province, clear, effective salt reduction interventions and policies that can be widely promoted have not yet been formed. This study sought to understand the prevalence and precise measures of salt reduction behavior, the variables affecting salt reduction behavior, and the reasons why salt reduction behavior was not practiced in Anhui Province, China.

Methods

The total number of participants in the study was 3,378. Using a multi-stage stratified cluster random sampling method, residents between the ages of 18 and 69 years in 10 counties and districts were selected from March to October 2019. A survey questionnaire and physical measurements were given to each participant. The influencing factors of residents' salt reduction behavior were examined using a multi-factor unconditional logistic regression analysis. The chi-squared (χ2) test was used to analyze the implementation of salt reduction behaviors among different age groups and gender, the factors influencing the implementation of salt reduction measures, and the reasons for not implementing salt reduction measures.

Results

A history of hypertension was associated with salt reduction strategies (P = 0.014). Patients with hypertension were more likely to adopt salt reduction behaviors than those without hypertension (OR = 1.218, P = 0.040). The influence of eating out on the adoption of salt-reduction measures varied by age group (χ2 = 50.463, P < 0.001) and gender (χ2 = 81.348, P < 0.001).

Conclusion

In summary, residents of the Anhui Province are not very knowledgeable about salt reduction. Age, gender, education level, hypertension, and marital status are the main determinants. Our findings have significant implications for policymakers who want to devise salt reduction strategies.

Adipocyte dysfunction promotes lung inflammation and aberrant repair: a potential target of COPD

Background

Obesity and chronic obstructive pulmonary disease (COPD) are prevailing worldwide, bringing a heavy medical burden. Clinical and pathophysiological relationship between obesity and COPD is paradoxical and elusive. We aim to explore their inherent associations from clinical, genetic, and animal levels.

Methods

We performed literature review and cohort analysis of patients with COPD to compare lung function, symptom, and prognosis among different weight groups. After retrieving datasets of obesity and COPD in Gene Expression Omnibus (GEO) database, we carried out differentially expressed gene analysis, functional enrichment, protein-protein interactions network, and weighted gene co-expression network analysis. Then, we acquired paraffin-embedded lung tissues of fatty acid-binding protein 4-Cre-BMPR2fl/fl conditional knockout (CKO) mice that were characterized by adipocyte-specific knockout of bone morphogenetic protein receptor 2 (BMPR2) for staining and analysis.

Results

Our cohort study reports the effect of obesity on COPD is inconsistent with previous clinical studies. Lung function of overweight group was statistically superior to that of other groups. We also found that the inflammatory factors were significantly increased hub genes, and cytokine-associated pathways were enriched in white adipose tissue of patients with obesity. Similarly, injury repair-associated genes and pathways were further enhanced in the small airways of patients with COPD. CKO mice spontaneously developed lung injury, emphysema, and pulmonary vascular remodeling, along with increased infiltration of macrophages. BMPR2-defiecient adipocytes had dysregulated expression of adipocytokines.

Conclusion

Inflammation and abnormal repair might be potential mechanisms of the pathological association between obesity and COPD. BMPR2-associated adipocyte dysfunction promoted lung inflammation and aberrant repair, in which adipocytokines might play a role and thus could be a promising therapeutic target.

Association between fresh fruit consumption and the risk of chronic obstructive pulmonary disease-related hospitalization and death in Chinese adults: A prospective cohort study

BACKGROUND

Existing evidence suggests that fruit consumption is a significant influencing factor for chronic obstructive pulmonary disease (COPD), but this is unclear in the Chinese population. We examined the association of fresh fruit consumption with the risk of COPD-related hospitalization and death in a nationwide, population-based prospective cohort from China.

METHODS

Between 2004 and 2008, the China Kadoorie Biobank recruited >0.5 million adults aged 30 to 79 years from ten diverse regions across China. After excluding individuals diagnosed with major chronic diseases and prevalent COPD, the prospective analysis included 421,428 participants. Cox regression was used to calculate the hazard ratios (HRs) for the association between fresh fruit consumption and risk of COPD-related hospitalization and death, with adjustment for established and potential confounders.

RESULTS

During a mean follow-up of 10.9 years, 11,292 COPD hospitalization events and deaths were documented, with an overall incidence rate of 2.47/1000 person-years. Participants who consumed fresh fruit daily had a 22% lower risk of COPD-related hospitalization and death compared with non-consumers (HR = 0.78, 95% confidence interval [CI]: 0.71-0.87). The inverse association between fresh fruit consumption and COPD-related hospitalization and death was stronger among non-current smokers and participants with normal body mass index (BMI) (18.5 kg/m 2 ≤ BMI < 24.0 kg/m 2 ); the corresponding HRs for daily fresh fruit consumption were 0.78 (95% CI: 0.68-0.89) and 0.69 (95% CI: 0.59-0.79) compared with their counterparts, respectively.

CONCLUSIONS

High-frequency fruit consumption was associated with a lower risk of COPD in Chinese adults. Increasing fruit consumption, together with cigarette cessation and weight control, should be considered in the prevention and management of COPD.

Obesity Paradox in Lung Diseases: What Explains It?

BACKGROUND

Obesity is a globally increasing health problem that impacts multiple organ systems and a potentially modifiable risk factor for many diseases. Obesity has a significant impact on lung function and is strongly linked to the pathophysiology that contributes to lung diseases. On the other hand, reports have emerged that obesity is associated with a better prognosis than for normal weight individuals in some lung diseases, including pneumonia, acute lung injury/acute respiratory distress syndrome, chronic obstructive pulmonary disease, and lung cancer. The lesser mortality and better prognosis in patients with obesity is known as obesity paradox. While obesity paradox is both recognized and disputed in epidemiological studies, recent research has suggested possible mechanisms.

SUMMARY

In this review, we attempted to explain and summarize these factors and mechanisms, including immune response, pulmonary fibrosis, lung function, microbiota, fat and muscle reserves, which are significantly altered by obesity and may contribute to the obesity paradox in lung diseases. We also discuss contrary literature that attributes the "obesity paradox" to confounding.

KEY MESSAGES

The review will illustrate the possible role of obesity in the prognosis or course of lung diseases, leading to a better understanding of the obesity paradox and provide hints for further basic and clinical research in lung diseases.

Association of egg consumption with colorectal polyp prevalence: findings from the Lanxi Pre-Colorectal Cancer Cohort (LP3C) in China

Eggs contain high-quality protein, lavish vitamins and other bioactive nutrients but are rich in cholesterol. Our study is designed to assess the association of egg intake with polyp prevalence. A total of 7068 participants at a high risk of CRC from the Lanxi Pre-Colorectal Cancer Cohort Study (LP3C) were recruited. A food frequency questionnaire (FFQ) was utilized to obtain dietary data through a face-to-face interview. Cases of colorectal polyps were identified by electronic colonoscopy. The logistic regression model was exploited to achieve odds ratios (ORs) and 95% confidence intervals (CIs). Overall 2064 cases of colorectal polyps were identified in the 2018-2019 survey of LP3C. A positive association of egg consumption with colorectal polyp prevalence was found after the multivariable adjustment [OR_{Q4 vs. Q1} (95% CI): 1.23 (1.05-1.44); P_trend = 0.01]. However, a positive relationship disappeared after further adjustment for dietary cholesterol (P_trend = 0.37), which explained that the harmful role of eggs could be ascribed to the high content of dietary cholesterol. Besides, a positive trend was found between dietary cholesterol and polyp prevalence [OR (95% CI): 1.21 (0.99-1.47); P_trend = 0.04]. Furthermore, replacing 1 egg (50 g d^-1) with an equal amount of total dairy products was related to 11% lower colorectal polyp prevalence [OR (95% CI): 0.89 (0.80-0.99); P = 0.03]. In summary, higher egg consumption was correlated with a higher polyp prevalence among the Chinese population at a high risk of CRC, which was ascribed to the high content of dietary cholesterol in eggs. Besides, individuals with the highest dietary cholesterol tended to have a higher polyp prevalence. Reducing the consumption of eggs and replacing eggs with total dairy products as alternative protein sources may prevent the occurrence of polyps in China.

Body Composition and COPD: A New Perspective

The proportion of obese or overweight patients in COPD patients is increasing. Although BMI, WC and other easy to measure indicators have been proven to be related to the risk of COPD, they cannot accurately reflect the distribution and changes of body composition, ignoring the body composition (such as fat distribution, muscle content, water content, etc.), the relationship between it and disease risk may be missed. By analyzing the correlation between different body composition indexes and COPD patients, we can provide new research ideas for the prognosis judgment or intervention of COPD disease.

Association between Fish Consumption and Risk of Chronic Obstructive Pulmonary Disease among Chinese Men and Women: an 11-Year Population-Based Cohort Study

BACKGROUND

Epidemiological evidence on the relation between fish consumption and chronic obstructive pulmonary disease (COPD) is limited, especially among Chinese.

OBJECTIVES

The aim was to explore the prospective association between fish consumption and COPD among a large population-based Chinese cohort.

METHODS

The China Kadoorie Biobank recruited over 0.5 million participants from 10 geographically diverse regions across China from 2004 to 2008. Consumption frequency of fish at baseline was assessed by a validated food-frequency questionnaire. A total of 169,188 men and 252,238 women who had no prior COPD or other major chronic diseases at baseline were included in our analyses. Cox proportional hazard models were used to estimate HRs and 95% CIs for fish consumption categories in relation to incident COPD.

RESULTS

During a median follow-up of 11.1 y, 11,292 incident COPD cases were documented. Fish consumption was inversely associated with COPD risk among women, with a 17% reduction in risk for participants who consumed fish ≥4 d/wk compared with nonconsumption (HR: 0.83; 95% CI: 0.70, 0.99; P-trend = 0.017), whereas we did not observe such a dose-response relation among men (HR: 0.89; 95% CI: 0.76, 1.05; P-trend = 0.373). The joint analysis showed that COPD risk was 38% and 48% lower in men and women who consumed fish ≥4 d/wk and had a healthy lifestyle [having ≥4 of the following healthy lifestyle factors: not smoking currently; never or rarely drinking alcohol; adequate physical activity; BMI (kg/m2): 18.5-23.9; normal waist circumference; reasonable diet], compared with participants with fish consumption <4 d/wk and an unhealthy lifestyle (≤1 factors).

CONCLUSIONS

Higher fish consumption was associated with lower COPD risk among Chinese women but not men. This association was independent of lifestyle factors. Eating adequate fish with an overall healthy lifestyle might help lower the risk of COPD.

Daytime napping, comorbidity profiles, and the risk of sarcopenia in older individuals

Appropriate daytime napping is associated with the decreased risk of cerebro-cardiovascular diseases, but whether daytime napping affects sarcopenia remains to be explored. Our study plans to examine the associations between sarcopenia with daytime napping and comorbidity. The study population came from the China Health and Retirement Longitudinal Study 2011-2015. Latent class analysis (LCA) was used to identify comorbidity profiles based on 14 doctor-diagnosed chronic diseases. Subsequently, smooth function and restricted cubic spline with three binomial regression models determined the associations between sarcopenia with daytime napping and comorbidity profiles. About 18.7% (2,894) and 5.4% (832) of 15,404 individuals were diagnosed with sarcopenia and severe sarcopenia. LCA delineated four classes as the best fit as follows: dominant heart diseases or risks (class 1, N = 2,203), dominant chronic lung diseases (class 2, N = 740), minimal or least diseases (class 3, N = 10,612, reference), and dominant digestive diseases and rheumatism (class 4, N = 1849). Compared with the reference group (class 3), the multivariate-adjusted ORs (95% CIs) of sarcopenia in model 3 were 0.72 (0.60-0.88) for class 1, 1.17 (0.92-1.51) for class 2, and 0.92 (0.77-1.09) for class 4. Smooth function and restricted cubic spline suggested that individuals who napped about 60 min seemingly had the lowest risk of sarcopenia. Individuals who napped for 1-59 min (adjusted OR = 0.80, 95% CI: 0.68-0.94) and 60-119 min (adjusted OR = 0.83, 95% CI: 0.72-0.95) had the significantly lower risk of sarcopenia but not severe sarcopenia than those who did not nap. Insufficient and excessive daytime napping might be associated with the increased risk of sarcopenia, especially in individuals with a dominant chronic lung disease profile.

Association between pregnancy and pregnancy loss with COPD in Chinese women: The China Kadoorie Biobank study

Background

Chronic obstructive pulmonary disease (COPD) is an inflammatory lung disease characterized by airflow blockage. Pregnancy and pregnancy loss may be related to an elevated risk of COPD, although studies have yet to report on this association. Hence, this study aims to investigate the association between pregnancy and pregnancy loss with the risk of COPD among Chinese women.

Methods

Data on 302,510 female participants from the China Kadoorie Biobank were utilized for this study. Multivariable logistic regression, stratified by sociodemographic and lifestyle factors, was employed to obtain the odds ratio (ORs) and 95% confidence intervals (CIs) for the association between pregnancy and pregnancy loss with COPD.

Results

Pregnancy loss was significantly associated with increased risk of COPD (OR 1.19, 95% CI 1.13-1.25), specifically, spontaneous (OR 1.19, 95% CI 1.11-1.29) and induced abortion (OR 1.18, 95% CI 1.12-1.25). Stillbirth, however, was not significantly associated with the risk of COPD (OR 1.09, 95% CI 0.99-1.20). Increasing number of pregnancy losses was associated with increasing risk of COPD (one pregnancy loss: OR 1.14, 95% CI 1.07-1.21, two or more pregnancy loss: OR 1.25, 95% CI 1.17-1.32, and each additional pregnancy loss: OR 1.06, 95% CI 1.03-1.09). A single pregnancy was significantly associated with reduced risk of COPD (OR 0.75, 95% CI 0.59-0.97), although each additional pregnancy was significantly associated with increased risk of COPD (OR 1.03, 95% CI 1.01-1.04).

Conclusion

Pregnancy loss, in particular, spontaneous and induced abortions are associated with increased risk of COPD among Chinese women. A single pregnancy, however, demonstrated protective effects.

Chronic Obstructive Pulmonary Disease Prevalence and Associated Risk Factors in Adults Aged 40 Years and Older in Southeast China: A Cross-Sectional Study During 2019-2020

Purpose

Chronic obstructive pulmonary disease (COPD) is one of many major public health problems in China, and its prevalence and associated risk factors in the southeast of China need to be determined to facilitate disease control and prevention.

Methods

A multistage stratified cluster sampling method was used to select 5486 participants aged ≥ 40 years from nine COPD monitoring districts in Fujian Province during 2019–2020. Participants were interviewed using a laptop-based questionnaire and underwent pulmonary function tests. COPD was diagnosed according to the 2019 Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.

Results

Final analysis was conducted using data from 4999 participants with qualified post-bronchodilator results. The prevalence of COPD was 11.6% (95% confidence interval [CI]: 10.5–12.7). Risk factors for COPD in the logistic regression model were being male (odds ratio [OR] = 2.83, 95% CI: 2.01–3.98), > 70 years old (OR = 16.16, 95% CI: 8.14–32.08), having a low body mass index (BMI) (OR = 1.81, 95% CI: 1.13–2.89), parental history of respiratory disease (OR = 1.78, 95% CI: 1.50–2.10), being a current (OR = 2.82, 95% CI: 1.83–4.36) or former (OR = 2.47, 95% CI: 1.45–4.19) smoker, and indoor exposure to biomass (OR = 1.28, 95% CI: 1.05–1.58).

Conclusion

The estimated prevalence of COPD in southeast China is high. COPD was strongly associated with sex, aging, a low BMI, parental history of respiratory diseases, smoking, and indoor exposure to biomass in adults aged ≥ 40 years. The government should urgently implement comprehensive measures to reduce the risk factors for COPD.

Nonadherence to health promotion depending on chronic obstructive pulmonary disease severity

BACKGROUND

Nonadherence to recommended health behaviors reportedly correlates with the prevalence and health outcomes of COPD, but the factors contributing to multiple health promotions are not well understood.

OBJECTIVE

To examine the factors associated with nonadherence to health behaviors, specifically focusing on COPD severity.

METHODS

We conducted a secondary data analysis with data from the 2016-2019 Korea National Health and Nutrition Examination Survey. The analyzed data were from 1,627 individuals aged over 40 years who had a FEV1/FVC ratio < 70% measured via spirometer. In this study, nonadherence to health behaviors is the sum of seven health-promoting behaviors in terms of smoking cessation, alcohol abstinence, regular exercise, weight control, recommended sleep time, influenza vaccination, and medical check-up.

RESULTS

COPD patients' nonadherence to health behaviors was significantly associated with comorbidity (p=0.017), stress (p=0.002), and COPD severity (moderate, severe; p=0.010, p=0.039, respectively). In addition, the moderate and severe COPD groups showed a higher nonadherence rate than the mild COPD group. Specifically, nonadherence to weight control was the most significantly different behavior according to COPD severity levels, based on the GOLD classification of airflow limitation.

CONCLUSION

Our study findings support that those with higher levels of stress, comorbidities, and severe disease conditions are less likely to adhere to health behaviors. Thus, healthcare providers and policymakers should provide tailored approaches according to COPD severity to educate and support appropriate health behaviors for individuals with COPD.

Associations Between Incident Asthma With Comorbidity Profiles, Night Sleep Duration, and Napping Duration Trajectories: A 7-Year Prospective Study

Objectives: We aim to determine whether comorbidity profiles, night sleep duration, and napping duration trajectories were associated with incident asthma in Chinese adults.

Methods: A total of 7,655 community-dwelling individuals were included in this study. Latent class/profile analysis(LCA/LPA) identified comorbidity profiles, night sleep duration, and napping duration trajectories. A generalized additive model with binomial regression assessed the associations between incident asthma with sleep trajectories.

Results: During a 7-year follow-up period, 205 individuals were newly diagnosed with asthma. LPA identified four trajectories of night sleep duration: dominant short (n = 2,480), dominant healthy-long (n = 1,405), long decreasing (n = 1875), and short increasing (n = 1895). We also found three trajectories of napping duration: short increasing (n = 3,746), stable normal (n = 1,379), and long decreasing (n = 2,530). We found three comorbidity profiles: dominant heart diseases or risks (n = 766), multiple disorders (n = 758), and minimal or least disorders (n = 6,131). Compared with dominant short night sleep duration, three other trajectories were associated with significantly decreasing incident asthma. Minimal or least disorders profile was associated with a significant reduction of new-onset asthma than two other comorbidity profiles in dominant short night sleep duration.

Conclusion: Our findings suggested that a dominant short night sleep duration trajectory potentially increases incident asthma in Chinese adults.

Multimorbidity patterns and association with mortality in 0.5 million Chinese adults

BACKGROUND

Few studies have assessed the relationship between multimorbidity patterns and mortality risk in the Chinese population. We aimed to identify multimorbidity patterns and examined the associations of multimorbidity patterns and the number of chronic diseases with the risk of mortality among Chinese middle-aged and older adults.

METHODS

We used data from the China Kadoorie Biobank and included 512,723 participants aged 30 to 79 years. Multimorbidity was defined as the presence of two or more of the 15 chronic diseases collected by self-report or physical examination at baseline. Multimorbidity patterns were identified using hierarchical cluster analysis. Cox regression was used to estimate the associations of multimorbidity patterns and the number of chronic diseases with all-cause and cause-specific mortality.

RESULTS

Overall, 15.8% of participants had multimorbidity. The prevalence of multimorbidity increased with age and was higher in urban than rural participants. Four multimorbidity patterns were identified, including cardiometabolic multimorbidity (diabetes, coronary heart disease, stroke, and hypertension), respiratory multimorbidity (tuberculosis, asthma, and chronic obstructive pulmonary disease), gastrointestinal and hepatorenal multimorbidity (gallstone disease, chronic kidney disease, cirrhosis, peptic ulcer, and cancer), and mental and arthritis multimorbidity (neurasthenia, psychiatric disorder, and rheumatoid arthritis). During a median of 10.8 years of follow-up, 49,371 deaths occurred. Compared with participants without multimorbidity, cardiometabolic multimorbidity (hazard ratios [HR] = 2.20, 95% confidence intervals [CI]: 2.14 - 2.26) and respiratory multimorbidity (HR = 2.13, 95% CI:1.97 - 2.31) demonstrated relatively higher risks of mortality, followed by gastrointestinal and hepatorenal multimorbidity (HR = 1.33, 95% CI:1.22 - 1.46). The mortality risk increased by 36% (HR = 1.36, 95% CI: 1.35 - 1.37) with every additional disease.

CONCLUSION

Cardiometabolic multimorbidity and respiratory multimorbidity posed the highest threat on mortality risk and deserved particular attention in Chinese adults.

Dietary Patterns and Risk of Chronic Obstructive Pulmonary Disease among Chinese Adults: An 11-Year Prospective Study

The evidence about the association between dietary patterns and the incidence of chronic obstructive pulmonary disease (COPD) among Chinese adults is limited. In the present study, we analyzed the prospective data of 421,426 participants aged 30−79 years from the China Kadoorie Biobank. Factor analysis with a principal component method was employed to identify dietary patterns. Cox proportional hazard regression models were performed to explore the association between dietary patterns and incident COPD. Two dietary patterns were identified: the traditional northern dietary pattern was characterized by a low intake of rice and a high intake of wheat and other staple foods, while the balanced dietary pattern was characterized by a high intake of fresh fruit and protein-rich foods (soybean, meat, poultry, fish, eggs, and dairy products). During a median follow-up of 11.13 years, 5542 men and 5750 women developed COPD. After adjustments for potential confounders, the balanced dietary pattern was associated with a lower risk of COPD (p for trend <0.001), with a hazard ratio (95% confidence interval) of 0.75 (0.67, 0.84) for those in the highest quintile compared with those in the lowest quintile. Such association was modified by sex, smoking status, and adiposity level.

Adiposity increases weight-bearing exercise-induced dyspnea despite favoring resting lung hyperinflation in COPD

Objectives

Our aim was to study the associations between resting lung hyperinflation, weight-bearing exercise-induced dyspnea and adipose distribution in obese and normal-weight COPD patients.

Methods

We performed a comparison between 80 obese COPD patients (COPDOB) with 80 age- and FEV1 matched normal-weight COPD patients (COPDNW). Dyspnea was assessed by the mMRC scale and the Borg dyspnea score before and after a 6 min walk test. Further characterization included spirometry, body plethysmography and metronome paced tachypnea (MPT) to estimate dynamic hyperinflation. Body composition was assessed with bioelectrical impedance analysis. Associations between dyspnea scores and BMI and body composition groups were studied using logistic regression models.

Results

COPDOB patients had attenuated increases in TLC, FRC and RV compared to COPDNW patients ( p < 0.01). The groups had comparable 6 min walking distance and ΔFRC upon MPT ( p > 0.05). Compared to COPDNW, COPDOB patients reported more often a mMRC ≥ 2 (65 vs 46%; p = 0.02; OR 3.0, 95% CI 1.4–6.2, p < 0.01) and had higher ΔBorg upon 6MWT: 2.0 (SEM 0.20) vs. 1.4 (SEM 0.16), p = 0.01; OR for ΔBorg ≥ 2: 2.4, 95% CI 1.1–5.2, p = 0.03. Additional logistic regression analyses on the associations between body composition and dyspnea indicated that increased body fat percentage, fat mass index and waist-to-hip ratio were associated with higher ORs for mMRC ≥ 2 and ΔBorg upon 6MWT ≥ 2.

Conclusion

Despite its beneficial effect on resting lung hyperinflation, adiposity is associated with increased weight-bearing exercise-induced dyspnea in COPD.

Epidemiological evidence relating risk factors to chronic obstructive pulmonary disease in China: A systematic review and meta-analysis

BACKGROUND

Chronic obstructive pulmonary disease (COPD), the most common chronic respiratory disease worldwide, not only leads to the decline of pulmonary function and quality of life consecutively, but also has become a major economic burden on individuals, families, and society in China. The purpose of this meta-analysis was to explore the risk factors for developing COPD in the Chinese population that resides in China and to provide a theoretical basis for the early prevention of COPD.

METHODS

A total of 2457 cross-sectional, case-control, and cohort studies published related to risk factors for COPD in China were searched. Based on the inclusion and exclusion criteria, 20 articles were selected. Stata 11.0 was used for meta-analysis. After merging the data, the pooled effect and 95% confidence intervals (CIs) were calculated to assess the association between risk factors and COPD. Heterogeneity between studies was assessed using I2 and Cochran's Q tests. Begg's test was used to assess publication bias.

RESULTS

Exposure to particulate matter less than 2.5 μm in diameter (PM2.5) (pooled effect = 1.73; 95%CI: 1.16~2.58; P <0.01), smoking history (pooled effect = 2.58; 95%CI: 2.00~3.32; P <0.01), passive smoking history (pooled effect = 1.39; 95%CI: 1.03~1.87; P = 0.03), male sex(pooled effect = 1.70; 95%CI: 1.31~2.22; P <0.01), body mass index (BMI) <18.5 kg/m2 (pooled effect = 1.73; 95%CI: 1.32~2.25; P <0.01), exposure to biomass burning emissions (pooled effect = 1.65; 95%CI: 1.32~2.06; P <0.01), childhood respiratory infections (pooled effect = 3.44; 95%CI: 1.33~8.90; P = 0.01), residence (pooled effect = 1.24; 95%CI: 1.09~1.42; P <0.01), and a family history of respiratory diseases (pooled effect = 2.04; 95%CI: 1.53~2.71; P <0.01) were risk factors for COPD in the Chinese population.

CONCLUSION

Early prevention of COPD could be accomplished by quitting smoking, reducing exposure to air pollutants and biomass burning emissions, maintaining body mass index between 18.5 kg/m2 and 28 kg/m2, protecting children from respiratory infections, adopting active treatments to children with respiratory diseases, and conducting regular screening for those with family history of respiratory diseases.

Association of preserved vegetable consumption and prevalence of colorectal polyps: results from the Lanxi Pre-colorectal Cancer Cohort (LP3C)

PURPOSE

Although fresh vegetable consumption has been linked with a lower risk of colorectal polyps, a precursor lesion for colorectal cancer (CRC), the association between preserved vegetable consumption and colorectal polyps is unknown. We aimed to assess the association of preserved vegetable intake with the prevalence of colorectal polyps with the consideration of subsites, sizes and multiplicity of polyps.

METHODS

We analyzed the cross-sectional data from 40-80 years Chinese at a high risk of CRC from the Lanxi Pre-colorectal Cancer Cohort (LP3C) baseline survey, which was conducted between March 2018 and December 2019. Dietary information was obtained via a validated food frequency questionnaire. Multivariate logistic regression was employed to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) of preserved vegetable consumption and the prevalence of colorectal polyps.

RESULTS

Of 6783 eligible participants in 2018-2019 survey of LP3C, 2064 prevalent colorectal polyp cases were identified. In the multivariable-adjusted model, preserved vegetable consumption was positively associated with the prevalence of colorectal polyps (OR for fourth vs. first quartile: 1.18; 95% CI 1.01-1.36; P trend = 0.02). The similar association was also detected for small polyps [OR_{Q4 vs Q1} (95% CI): 1.17 (1.00-1.37); P trend = 0.03]. The similar trend was detected for multiple polyps [OR _{Q4 vs Q1} (95% CI):1.27 (0.98-1.64); P trend = 0.04], proximal colon polyps [OR_{Q4 vs Q1} (95% CI): 1.12 (0.90-1.38); P trend = 0.07], and single polyp [OR_{Q4 vs Q1} (95% CI) for 1.15 (0.98-1.35); P trend = 0.06]. No significant association was observed for distal colon [OR_{Q4 vs Q1} (95% CI) 1.19 (0.98-1.45); P trend = 0.09]. Replacing one serving per day of preserved vegetables with fresh vegetables was related to 20%, 23%, and 37% lower prevalence of overall, small, and multiple polyps, respectively.

CONCLUSIONS

Preserved vegetable consumption was associated with a higher prevalence of colorectal polyps in a Chinese population at a high risk of CRC. Replacing preserved vegetables with fresh vegetables may be conducive to lower prevalent colorectal polyps.

A large-scale genome-wide association analysis of lung function in the Chinese population identifies novel loci and highlights shared genetic aetiology with obesity

BACKGROUND

Lung function is a heritable complex phenotype with obesity being one of its important risk factors. However, knowledge of their shared genetic basis is limited. Most genome-wide association studies (GWASs) for lung function have been based on European populations, limiting the generalisability across populations. Large-scale lung function GWASs in other populations are lacking.

METHODS

We included 100 285 subjects from the China Kadoorie Biobank (CKB). To identify novel loci for lung function, single-trait GWAS analyses were performed on forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC in the CKB. We then performed genome-wide cross-trait analysis between lung function and obesity traits (body mass index (BMI), BMI-adjusted waist-to-hip ratio and BMI-adjusted waist circumference) to investigate the shared genetic effects in the CKB. Finally, polygenic risk scores (PRSs) of lung function were developed in the CKB and their interaction with BMI's association on lung function were examined. We also conducted cross-trait analysis in parallel with the CKB using up to 457 756 subjects from the UK Biobank (UKB) for replication and investigation of ancestry-specific effects.

RESULTS

We identified nine genome-wide significant novel loci for FEV1, six for FVC and three for FEV1/FVC in the CKB. FEV1 and FVC showed significant negative genetic correlation with obesity traits in both the CKB and UKB. Genetic loci shared between lung function and obesity traits highlighted important biological pathways, including cell proliferation, embryo, skeletal and tissue development, and regulation of gene expression. Mendelian randomisation analysis suggested significant negative causal effects of BMI on FEV1 and on FVC in both the CKB and UKB. Lung function PRSs significantly modified the effect of change in BMI on change in lung function during an average follow-up of 8 years.

CONCLUSION

This large-scale GWAS of lung function identified novel loci and shared genetic aetiology between lung function and obesity. Change in BMI might affect change in lung function differently according to a subject's polygenic background. These findings may open new avenues for the development of molecular-targeted therapies for obesity and lung function improvement.

Twenty-Year Trajectory-Patterns of Percentage Energy From Dietary Fat vs. Carbohydrate Throughout Adult Life and Associations With Cardio-Metabolic Disease and All-Cause Mortality

Background: The health impacts of dietary fat-to-energy ratio (FER) compared to carbohydrate-to-energy ratio (CER) are widely discussed topics in public health. This study aimed to assess the health impacts of FER and CER by establishing trajectory-patterns of FER and CER over the course of adult life. Methods: This study used the weighted longitudinal data of the China Health and Nutrition Survey, including eight surveys from 1991 to 2011. The trajectories of FER and CER were determined via latent class trajectory modeling. The trajectories were then cross-grouped into different trajectory-patterns. Multivariate Cox regression models were used to assess the relationship between these trajectory-patterns and cardio-metabolic diseases and all-cause mortality. Ten thousand nine hundred and twenty-six adults with a total of 50,693 observations across eight surveys were included. Results: Compared to the trajectory-pattern of persistently low-FER (increased from 10 to 20%) and moderate-CER (stable and ranging from 55 to 65%) over the adult life-course, the two trajectory-patterns that showed changing to high-FER and low-CER were significantly associated with obesity [HR 1.83 [95% CI, 1.10-3.04]; HR 1.46 [95% CI, 1.02-2.17]], diabetes [HR 1.80 [95% CI, 1.03-3.16]; HR 1.49 [95% CI, 1.01-2.25]], and all-cause mortality [HR 2.29 [95% CI, 1.35-3.87]; HR 1.62 [95% CI, 1.18-2.22]]. In contrast, the trajectory-pattern of a persistently low-FER and high-CER diet was not associated with obesity [HR 1.19 [95% CI, 0.82-1.17]], diabetes [HR 1.41 [95% CI, 0.98-2.02]], cardiovascular-disease [HR 1.48 [95% CI, 0.91-2.39]], and all-cause mortality [HR 1.23 [95% CI, 0.94-1.61]]. Conclusions: This study indicates that changing to a high-FER and low-CER diet over the course of adult life was significantly associated with obesity, diabetes, and all-cause mortality in the Chinese adult population. In addition, low-FER and high-CER were not associated with cardio-metabolic disease and all-cause mortality. These observations may provide insights into nutritional policy and dietary guidelines.

Association between obesity and chronic obstructive pulmonary disease in Moroccan adults: Evidence from the BOLD study

Objective:

The Moroccan cross-sectional study aimed to investigate obesity in association to chronic obstructive pulmonary disease in Fez city.

Methods:

A cross-sectional survey was carried out in Moroccan adults. Anthropometric and spirometry measurements were performed using standardized guidelines.

Results:

Among the 744 participants, 53.9% of were women, with a mean age of 55.27 years (SD = 10.29). Nearly all women declared themselves to be never smokers, while 21% of men were current smokers. Overall, chronic obstructive pulmonary disease prevalence decreased with body mass index (p = 0.01) and waist circumference (p < 0.001). The same trends were also observed in women. The adjusted regression analysis showed a significant independent association between chronic obstructive pulmonary disease and decreasing overweight (OR_a: 0.66; CI_95% (0.40–0.98)), obesity (OR_a: 0.66 CI_95%: (0.36–0.89)), and a decreasing waist circumference-abdominal obesity (OR_a: 0.58 CI_95%: (0.34–0.99)) in the whole population. The same association remains significant in women for overweight (OR_a: 0.18 CI_95%: (0.06–0.54)) and for waist circumference-abdominal obesity (OR_a: 0.40 CI_95%: (0.19–0.85)). All these associations disappeared for men.

Conclusion:

Chronic obstructive pulmonary disease decreases with the increase in body mass index and waist circumference. The effect of waist circumference on the chronic obstructive pulmonary disease was greater among women, regardless of the tobacco factor. A multicenter study would help to confirm the accuracy of these findings in a larger sample of the Moroccan population. Developed lifestyle programs in patients with chronic obstructive pulmonary disease should be considered.

An assessment of anthropometric indices and its association with NCDs among the older adults of India: evidence from LASI Wave-1

BACKGROUND

The purpose of this study is to assess the status of physical body indices such as body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) among the older adults aged 45 and above in India. Further, to explore the association of anthropometric indices with various non-communicable morbidities.

METHODS

The study uses secondary data of the Longitudinal Ageing Survey's first wave in India (2017-18). The national representative sample for older adults 45 and above (65,662) considered for the analysis. The prevalence of the non-communicable diseases (NCDs) included in the study is based on the self-reporting of the participants. Diseases included are among the top ten causes of death, such as cancer, hypertension, stroke, chronic heart diseases, diabetes, chronic respiratory diseases, and multi-morbidity. Multi-morbidity is a case of having more than one of the morbidities mentioned above. BMI-obese indicates an individual having a BMI ≥30, and the critical threshold value for high-risk WC for men is ≥102 cm while for women is ≥88 cm. The critical limit for the high-risk WHR for men and women is ≥0.90 and ≥ 0.85, respectively. Descriptive statistics and multiple logistic regressions are used to assess the association BMI, WC, and WHR with non-communicable morbidities.

RESULTS

Based on the multivariate-adjusted model, odds shows that an Indian older adult aged 45 and above is 2.3 times more likely (AOR: 2.33; 95% CI (2.2, 2.5)) by obesity, 61% more likely (AOR: 1.61; 95% CI (1.629, 1.631)) by high-risk WHR and 98% more likely (AOR: 1.98; 95% CI (1.9, 2.1)) by high-risk WC to develop CVDs than their normal counterparts. Similarly, significant positive associations of obesity, high-risk WC, and high-risk WHR were observed with other NCDs and multi-morbidity.

CONCLUSION

Our study shows that obesity, high-risk WC, and high-risk WHR are significant risks for developing NCDs and multi-morbidity among the older adults in India. There is a need for a multi-sectoral approach to reduce the share of the elderly population in high-risk groups of BMIs, WHR, and WC.

Association of Body Mass Index with Risk of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

The association between body mass index (BMI) and chronic obstructive pulmonary disease (COPD) remains controversial. Therefore, a meta-analysis was conducted to further evaluate the relationship. A comprehensive literature search was performed in PubMed, Web of Science, EMBASE, China National Knowledge Infrastructure (CNKI), and Wanfang databases to identify eligible articles until July 15, 2020. Random effect model (REM) was used to compute the pooled results with 95% confidence intervals (CIs). We conducted meta-regression and subgroup analysis to explore potential sources of heterogeneity. Publication bias was evaluated by funnel plots and Egger's test. Thirty articles with 1,578,449 participants were included in the meta-analysis. The pooled OR of COPD was 1.96 (95% CI: 1.78-2.17) for the underweight group, 0.80 (95% CI: 0.73-0.87) for overweight group, and 0.86 (95% CI: 0.73-1.02) for obesity group. After further excluding 5 studies of high between-study heterogeneity in sensitivity analysis, the pooled OR of COPD was 0.77 (95% CI: 0.68-0.86) for the obesity group. This meta-analysis indicated that BMI was associated with COPD. Specifically, underweight might increase the risk of COPD; overweight and obesity might reduce the risk of COPD.

Current developments and future directions in COPD

The European Respiratory Society journals publish respiratory research and policy documents of the highest quality, offering a platform for the exchange and promotion of scientific knowledge. In this article, focusing on COPD, the third leading cause of death globally, we summarise novel research highlights focusing on the disease's underlying mechanisms, epidemiology and management, with the aim to inform and inspire respiratory clinicians and researchers.

Current developments and future directions in COPD: a critical summary of some of the most recent ground-breaking research studies and policy documents from @ERSpublicationshttps://bit.ly/3oW0xDM

Use of the COPD Assessment Test (CAT) to screen for COPD in dairy farmers: AIRBAg study

OBJECTIVES

People at risk of chronic obstructive pulmonary disease (COPD) can benefit from appropriate medical management before severe symptoms appear. This study assesses the value of the COPD Assessment Test (CAT) questionnaire for screening dairy farmers, who tend to be slow or reluctant to seek health care.

METHODS

During the time period 2012-2017, 2089 randomly selected dairy farmers in Brittany (France) were invited to complete self-administered questionnaires (including the CAT) and to undergo an occupational health check-up using an electronic mini-spirometer and conventional spirometry. Those showing symptoms suggestive of COPD and/or a ratio FEV₁ /FEV₆ < 80% were sent to a pulmonologist for a further check-up, including spirometry with a reversibility test. Multivariate logistic models based on CAT scores and socio-demographic or work-related factors were developed to predict COPD.

RESULTS

The 1231 farmers who underwent the occupational health check-up included 1203 who met the inclusion/exclusion criteria. Pulmonologist identified 16 (1.3%) cases of COPD. A multivariate logistic regression model (covariates: CAT sum score, on-farm time, BMI, smoking status, free-stall mulching) provided an area under the receiver-operating characteristic curve (AUC) of 0.87 (95% CI: 0.75-0.98). Using a cut-off of 0.007 gave a sensitivity of 93.8% and a specificity of 62.4%. Another model that included CAT breathlessness and the same covariates performed marginally better (AUC = 0.88, 95% CI: 0.77-0.98).

CONCLUSION

Our predictive models can both benefit dairy farmers by providing early diagnosis and management of their COPD and avoid unnecessary, costly spirometry during the screening process.

Prevalence of, and risk factors for underweight or excess weight in patients with chronic obstructive emphysema from a multiethnic region of Xinjiang, China

BACKGROUND

The purpose of this study is to assess the basic nutritional status (body metabolic index, BMI) and its risk factors in the patients suffering from chronic obstructive emphysema.

METHODS

We described their demographic characteristics and comorbidity distribution of 2812 obstructive emphysema participants. Comparative analyzes were conducted on BMI with different demographic characteristics and comorbidities status, and comprehensive analysis on risk factors of excess weight and underweight in patients with different characters.

RESULTS

The prevalence of underweight and excess weight was 17.57% and 31.54% respectively. There were differences in the distribution of three types of body mass index among patients with different demographic characteristics and different comorbidities. The study found that age of 50 ~ 64 (odds ratio, OR: 2.99), tuberculosis (OR: 2.41), and low TG (OR: 2.32) were the risk factors about underweight. Low HDL-C (OR: 4.15), nonalcoholic fatter liver (NAFLD) (OR: 3.96), and age of 50 ~ 64 (OR: 2.72) were closely related to the excess weight of participants.

CONCLUSIONS

This study highlighted the prevalence of underweight and excess weight in patients among emphysema. Comorbidities were important risk factors of underweight or excess weight among chronic emphysema patients. These findings were important for the prevention and treatment of chronic obstructive emphysema in the future.

Association between sleep duration and asthma in different weight statuses (CHNS 2009-2015)

PURPOSE

Inadequate sleep duration affects asthma and weight. The associations among sleep duration, asthma, and different weight statuses in the Chinese population need to be further determined.

METHODS

The study included 32,776 Chinese adults from the China Health and Nutrition Survey during 2009-2015. Self-reported sleep duration was classified into three groups: ≤ 6 h (short), 7 to 8 h (optimal), and ≥ 9 h (long). Age, sex, smoking, drinking alcohol, and residence location were adjusted as potential confounding factors in a generalized estimating equations model.

RESULTS

The prevalence of asthma in the Chinese population was approximately 1.17% (383/32,776). Asthmatics were associated with shorter sleep duration and higher indices of central obesity (mean waist circumference, waist to height ratio, and conicity index) than the population without asthma. After adjusting for potential confounding factors, odds ratios (ORs) indicated positive associations between sleep duration and asthma (short vs optimal, adjusted OR = 1.74, 95%CI 1.33, 2.26; and long vs optimal, adjusted OR = 1.51, 95%CI 1.18, 1.93). When stratified by weight status, the participants with central obesity showed highest prevalence of asthma among the three sleep duration groups. With the adjustment of confounding factors, underweight and obesity grouped by waist to height ratio and conicity index remained associated with higher risk of asthma among short and long sleepers than in optimal sleepers.

CONCLUSIONS

Short and long sleepers with central obesity and underweight status were associated with significantly higher prevalence of asthma than optimal sleepers in Chinese adults.