The effect of low body mass index on the development of chronic obstructive pulmonary disease and mortality

Development and validation of a nomogram for predicting COPD: A nationwide population-based study in South Korea

Chronic obstructive pulmonary disease (COPD) remains a significant global health burden exacerbated by tobacco smoking, occupational exposure, and air pollution. COPD is one of the top 3 causes of death worldwide. In South Korea, the COPD burden is expected to increase due to ongoing exposure to risk factors and the aging population. COPD is extensively underdiagnosed or underestimated, owing to a lack of public awareness. This study aimed to develop and validate a nomogram for COPD by using national data to promote early diagnosis and intervention. This study drew on a dataset from the 7th Korea National Health and Nutrition Examination Survey from 2016 to 2018, including 10,819 subjects aged 40 years or older with spirometry results. Influence of demographic, socioeconomic, and health-related factors on the incidence. Multivariable logistic regression was used to identify the significant predictors of the nomogram. The nomogram was validated using receiver operating characteristic curves, calibration plots, and concordance index (C-index). Internal validation was performed by bootstrapping. In the final analysis, 1059 (14.0%) participants had COPD. Key risk factors associated with increased COPD risk included being male, aged 70 and older, lower educational level, living in a rural area, current smoking status, underweight, and history of tuberculosis and asthma. The area under the curve (AUC) of the model was 0.822 (95% CI: 0.810-0.832), indicating that the nomogram has a high ability to identify COPD. The nomogram demonstrated solid predictive performance, as confirmed by calibration plots with a C-index (of 0.822) for the validation set with 1000 bootstrap samples. In conclusion, we developed a tool for the early detection of COPD with good properties in primary care settings, without spirometry. Appropriate and early diagnosis of COPD can have a crucial impact on public health.

Risk and effect modifiers for poor glycemic control among the chinese diabetic adults on statin therapy: the kailuan study

BACKGROUND

Limited studies have investigated the association between statin therapy and poor glycemic control, especially in the Chinese diabetic population.

METHODS

Two prospective diabetes cohorts were drawn from the Kailuan Cohort. In Cohort 1, linear regression models were used to evaluate the association between statin therapy and glycated hemoglobin (HbA1c) level change. In Cohort 2, new user design and conditional logistic models were used to assess associations between statin initiation and poor glycemic control which was a composite outcome comprised of hypoglycemic agent escalation and new-onset hyperglycemia.

RESULTS

Among 11,755 diabetic patients with medication information, 1400 statin users and 1767 statin nonusers with repeated HbA1c measurements were included in Cohort 1 (mean age: 64.6 ± 10.0 years). After a median follow-up of 3.02 (1.44, 5.00) years, statin therapy was associated with higher HbA1c levels (β: 0.20%; 95%CI: 0.05% to 0.34%). In Cohort 2, 1319 pairs of matched cases/controls were included (mean age: 61.6 ± 9.75 years). After a median follow-up of 4.87 (2.51, 8.42) years, poor glycemic control occurred in 43.0% of statin new users and 31.8% of statin nonusers (OR: 1.69; 95% CI: 1.32 to 2.17; P < 0.001). The statin-associated poor glycemic control risk was significantly higher among patients with lower body mass index (Pint = 0.089). Furthermore, a nonlinear association was observed between statin therapy duration and poor glycemic control (P = 0.003).

CONCLUSIONS

Among Chinese diabetic adults, statin therapy was associated with a higher level of HbA1c, and a higher risk of hypoglycemic agent escalation and new-onset hyperglycemia, especially among those who had lower body mass index levels and longer statin therapy duration.

A study on the reasonable dietary trajectory of elderly people in the community and its correlation with body mass index

Objective

To explore the reasonable dietary trajectory of elderly people in the community and to test the correlation between different dietary trajectories and body mass index (BMI) of the elderly people in the community to provide a reference for these individuals to formulate scientific interventions and cultivate healthy living habits.

Methods

The data of The Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2011 to 2018 were used to evaluate the dietary status of elderly people in the community according to their diet, and body mass index was calculated according to height and weight. The latent variable growth mixed (LGMM) model was used to analyze the development trajectory of diet in elderly people, and the multivariate logistic regression model was used to test the relationship between different dietary development trajectories and BMI changes as well as to test the correlation between different dietary trajectories and BMI of the elderly people in the community.

Results

The LGMM fit four dietary trajectories of elderly individuals: the continuous reasonable diet group (37.81%), the dietary behavior decline group (28.84%), the continuous unreasonable diet group (20.16%), and the dietary behavior improvement group (13.19%). The results showed that factors including male sex, rural setting, being spouseless, nonformal education status, not being wealthy, living alone, and having tooth loss were more likely to be classified as the "persistently unreasonable diet group" (p < 0.05). The logistic regression results showed that the "continuous reasonable diet group" and the "dietary behavior improvement group" were significantly correlated with the development of obesity to a normal BMI.

Conclusion

The dietary behavior of the elderly was significantly correlated with BMI value, and improving the reasonable dietary behavior of the elderly could reduce the high BMI to the normal range, but could not restore the low BMI to the normal range, indicating that reasonable dietary behavior is an important measure to prevent and improve overweight or obesity in the elderly. There is significant heterogeneity in the dietary behavior of the elderly, and community medical staff should identify the risk factors of various dietary behaviors of other groups as soon as possible, and provide corresponding intervention strategies to help them change their poor dietary behaviors and improve their nutritional status.

Mortality Risk of Low BMI in Life Insurance Applicants

OBJECTIVES

-This study seeks to quantify the mortality effect of low levels of body mass index (BMI) on life insurance applicants who, based on their laboratory profile and other information, appear to be suitable for life insurance coverage.

BACKGROUND

-It has been demonstrated that low BMI is associated with higher mortality risk than normal or near-normal BMI.

METHODS

-Data were collected from over 4.7 million life insurance applicants with available BMI tested between 1995 and 2021, and vital status was assessed via the Social Security Death Master File. Cox models treating BMI as continuous and as a categorical variable were constructed, controlling for age, and split by sex after excluding those with laboratory or biometric test results, which were far enough outside the normal range to imply elevated mortality.

RESULTS

-Models treating BMI as a continuous variable and allowing an interaction term for age showed that low BMI was strongly associated with mortality at ages 50 and above in both sexes. In the categorical models, only the lowest category of BMI (below the 1st percentile) in men aged 40-60, the lowest 2 categories (below the 5th percentile) in women aged 40-60, and the lowest 3 categories (below the 10th percentile) in those aged 60-80 years, were significantly associated with elevated mortality. No elevated mortality was detected in those under age 40 with low BMI.

CONCLUSION

-Based on this study, low BMI is associated with elevated mortality in otherwise healthy applicants, but this association is dependent on age.

COPD in Never-Smokers: BOLD Australia Study

Purpose

Tobacco smoking is the major risk factor for COPD, and it is common for other risk factors in never-smokers to be overlooked. We examined the prevalence of COPD among never-smokers in Australia and identified associated risk factors.

Methods

We used data from the Australia Burden of Obstructive Lung Disease (BOLD) study, a cross-section of people aged ≥40 years from six sites. Participants completed interviews and post-bronchodilator spirometry. COPD was primarily defined as an FEV1/FVC ratio <0.70 and secondarily as the ratio less than the lower limit of normal (LLN).

Results

The prevalence of COPD in the 1656 never-smokers who completed the study was 10.5% (95% CI: 9.1-12.1%) [ratio

Conclusion

COPD was prevalent in this population of never-smokers aged 40 years and over. This finding highlights the significance of risk factors other than smoking in the development of COPD.

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Key Words

• BOLD
• LLN
• burden of obstructive lung disease
• lower limit of normal
• non-smokers
• prevalence
• spirometry

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MESH Headings

• Female
• Male
• Humans
• Adult
• Middle Aged
• Child
• Smokers
• Pulmonary Disease, Chronic Obstructive/diagnosis
• Pulmonary Disease, Chronic Obstructive/epidemiology
• Asthma
• Odds Ratio
• Australia/epidemiology

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Grants

• National Health and Medical Research Council (NHMRC) of Australia
• Thoracic Society of Australia and New Zealand
• Robert Pierce Grant-in-Aid for Indigenous Lung Health
• Air Liquide, AstraZeneca; GlaxoSmithKline; and Boehringer Ingelheim

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Affiliation(s)

Marsha A Ivey School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, 3004, Australia School of Medicine, Faculty of Medical Sciences, The University of the West Indies, St Augustine, Trinidad and Tobago
Sheree M Smith School of Nursing and Midwifery, Campbelltown Campus, Western Sydney University, Penrith, NSW, 2751, Australia Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
Geza Benke School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, 3004, Australia
Brett G Toelle Respiratory and Environmental Epidemiology Group, Woolcock Institute of Medical Research, Sydney, NSW, 2037, Australia Sydney Local Health District, Sydney, NSW, 2050, Australia
Michael L Hunter School of Population and Global Health, University of Western Australia, Perth, WA, 6009, Australia
Alan L James Department of Pulmonary Physiology and Sleep Medicine, Sir Charles Gairdner Hospital and Medical School, University of Western Australia, Perth, WA, 6009, Australia
Graeme P Maguire Curtin Medical School, Curtin University, Perth, WA, 6102, Australia
Richard Wood-Baker School of Medicine, University of Tasmania, Hobart, TAS, 7000, Australia
David P Johns Melbourne School of Population and Global Health, University of Melbourne, Melbourne, VIC, Australia
Guy B Marks Respiratory and Environmental Epidemiology Group, Woolcock Institute of Medical Research, Sydney, NSW, 2037, Australia School of Clinical Medicine, University of New South Wales, Sydney, NSW, 2052, Australia
Michael J Abramson School of Public Health and Preventive Medicine, Monash University, Melbourne, VIC, 3004, Australia

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The Effect of Chronic Laxative Use on Lipid Profile and HbA1c: A Hospital-Based Retrospective Study

BACKGROUND

Laxatives are over-the-counter medications used as a treatment for constipation. The lipid-lowering effect of the long-term use of laxatives has been proposed.

AIM

To investigate the possible impact of the chronic use of laxatives on serum lipid profile, body mass index (BMI), and hemoglobin A1c (HbA1c).

METHODS

An observational retrospective cohort study was conducted to analyze data related to patients who received laxatives for six or 12 months or more in the KAUH database system. BMI, weight, cholesterol, triglycerides, low-density lipoprotein (LDL), high-density lipoprotein (HDL), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and HbA1c data were collected retrospectively from hospital records for three time points: baseline, six months, and 12 months of laxative treatment from the starting date for each patient.

RESULTS

A total of 106 patients' records fulfilled the inclusion criteria, 46 (43%) males with a mean age of 66 and 60 (57%) females with a mean age of 63. A significant decrease in plasma cholesterol and low-density lipoprotein-cholesterol (LDL-C) levels was observed in those who used laxatives for 12 months. Furthermore, an overall BMI and ALT reduction was seen in the combined. On the other hand, HbA1c levels appeared to improve in the combined group but not statistically significant. The change in the cholesterol level could be observed in patients receiving statin treatment and those without, with no statistical significance between the two groups.

CONCLUSION

Chronic laxative use for 12 months or more is associated with a decreased total and LDL-C level with no significant effect on high-density lipoprotein-cholesterol (HDL-C) levels. Additionally, there was a significant reduction in BMI and ALT. This effect is more prominent with combined therapy. Further multicentric studies on larger sample sizes are recommended to confirm our findings.

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.

The Relationship of Cholesterol Responses to Mitochondrial Dysfunction and Lung Inflammation in Chronic Obstructive Pulmonary Disease

Hyperlipidemia is frequently reported in chronic obstructive pulmonary disease (COPD) patients and is linked to the progression of the disease and its comorbidities. Hypercholesterolemia leads to cholesterol accumulation in many cell types, especially immune cells, and some recent studies suggest that cholesterol impacts lung epithelial cells' inflammatory responses and mitochondrial responses. Several studies also indicate that targeting cholesterol responses with either statins or liver X receptor (LXR) agonists may be plausible means of improving pulmonary outcomes. Equally, cholesterol metabolism and signaling are linked to mitochondrial dysfunction and inflammation attributed to COPD progression. Here, we review the current literature focusing on the impact of cigarette smoke on cholesterol levels, cholesterol efflux, and the influence of cholesterol on immune and mitochondrial responses within the lungs.

Validation of Asian Body Mass Index Cutoff Values for the Classification of Malnutrition Severity According to the Global Leadership Initiative on Malnutrition Criteria in Patients with Chronic Obstructive Pulmonary Disease Exacerbations

Low body mass index (BMI) is an independent predictor of prolonged hospital stay and mortality in patients with chronic obstructive pulmonary disease (COPD). However, to the best of our knowledge, no studies have examined the validity of Asian BMI cutoff values for classifying severity based on the Global Leadership Initiative on Malnutrition (GLIM) criteria in patients with acute COPD exacerbations. This study sought to validate whether Asian BMI cutoff values can accurately predict 30-day in-hospital mortality, length of stay, and 90-day readmission outcomes for patients with acute COPD exacerbations. The present retrospective cohort study was conducted using a large claims database created by the JMDC. Patients were classified into three groups according to the severity of low BMI assessed using Asian BMI cutoff values. As a result, 624 (29.4%) had severely low BMI, and 444 (20.9%) had moderately low BMI. The severity of low BMI, as assessed by the Asian BMI cutoff values used in the GLIM criteria, was independently associated with 30-day in-hospital mortality (moderately low BMI: HR, 1.87; 95% CI, 1.13−3.08; p = 0.014 and severely low BMI: HR, 2.55; 95% CI, 1.66−3.92; p < 0.001). The Asian BMI cutoff values used to classify the severity of malnutrition in the GLIM criteria are clinically functional for predicting the prognosis of patients with acute COPD exacerbations.

High-Density Lipoproteins: A Role in Inflammation in COPD

Chronic obstructive pulmonary disease (COPD) is a widespread disease associated with high rates of disability and mortality. COPD is characterized by chronic inflammation in the bronchi as well as systemic inflammation, which contributes significantly to the clinically heterogeneous course of the disease. Lipid metabolism disorders are common in COPD, being a part of its pathogenesis. High-density lipoproteins (HDLs) are not only involved in lipid metabolism, but are also part of the organism's immune and antioxidant defense. In addition, HDL is a versatile transport system for endogenous regulatory agents and is also involved in the removal of exogenous substances such as lipopolysaccharide. These functions, as well as information about lipoprotein metabolism disorders in COPD, allow a broader assessment of their role in the pathogenesis of heterogeneous and comorbid course of the disease.

Nomograms for Predicting Coexisting Cardiovascular Disease and Prognosis in Chronic Obstructive Pulmonary Disease: A Study Based on NHANES Data

Background

Chronic obstructive pulmonary disease (COPD) is a common chronic disease. Progression is further exacerbated by the coexistence of cardiovascular disease (CVD). We aim to construct a diagnostic nomogram for predicting the risk of coexisting CVD and a prognostic nomogram for predicting long-term survival in COPD.

Methods

The 540 eligible participants selected from the NHANES 2005-2010 were included in this study. Logistic regression analysis was used to construct a diagnostic nomogram for the diagnosis of coexisting CVD in COPD. Cox regression analyses were used to construct a prognostic nomogram for COPD. A risk stratification system was developed based on the total score generated from the prognostic nomogram. We used C-index and ROC curves to evaluate the discriminant ability of the newly built nomograms. The models were also validated utilizing calibration curves. Survival curves were made using the Kaplan-Meier method and compared by the Log-rank test.

Results

Logistic regression analysis showed that gender, age, neutrophil, RDW, LDH, and HbA1c were independent predictors of coexisting CVD and were included in the diagnostic model. Cox regression analysis indicated that CVD, gender, age, BMI, RDW, albumin, LDH, creatinine, and NLR were independent predictors of COPD prognosis and were incorporated into the prognostic model. The C-index and ROC curves revealed the good discrimination abilities of the models. And the calibration curves implied that the predicted values by the nomograms were in good agreement with the actual observed values. In addition, we found that coexisting with CVD had a worse prognosis compared to those without CVD, and the prognosis of the low-risk group was better than that of the high-risk group in COPD.

Conclusions

The nomograms we developed can help clinicians and patients to identify COPD coexisting CVD early and predict the 5-year and 10-year survival rates of COPD patients, which has some clinical practical values.

Lower Prevalence of Osteoporosis in Patients with COPD Taking Anti-Inflammatory Compounds for the Treatment of Diabetes: Results from COSYCONET

Background

Patients with chronic obstructive pulmonary disease (COPD) often have osteoporosis and diabetes as comorbid conditions. Anti-diabetic medication, including metformin, has protective effects on osteoporosis in experimental studies. We therefore studied whether patients with COPD receiving anti-diabetic medication had a lower osteoporosis prevalence in a large COPD cohort, COSYCONET.

Methods

Assessment of osteoporosis was based on patients’ reports of physician-based diagnoses and the presence of disease-specific medication. The predictive value of physical characteristics, lung function, comorbidities, cardiovascular medication, and the use of anti-inflammatory diabetes medication, including metformin, sulfonylureas, glinides or DPP4I, was evaluated using logistic regression analysis. ClinicalTrials.gov: NCT01245933.

Results

In total, 2222 patients were eligible for analysis (863 [39%] female, mean age 65 y), 515 of whom had higher symptoms and exacerbations (Global Initiative for Chronic Obstructive Lung Disease group D). Osteoporosis was present in 15.8% of the overall cohort, and in 24.1% of GOLD D patients. Regression analyses identified the following as associated with osteoporosis (p < 0.05): female sex, higher age, lower body-mass index, asthma, higher air trapping, oral steroids, and cardiovascular medication. Although oral anti-diabetic medication was overall not associated with a lower prevalence of osteoporosis (p = 0.131), anti-inflammatory anti-diabetic medication (p = 0.009) and metformin-containing therapy (p = 0.039) were. This was driven by GOLD D patients.

Conclusion

In a large COPD cohort, anti-inflammatory diabetes therapy, including metformin, was associated with a lower prevalence of osteoporosis, especially in patients with higher symptoms and exacerbations. These findings suggest a protective effect of common anti-diabetic medication on osteoporosis, possibly as a result of attenuated systemic inflammation.

Clinical Practice Patterns of Speech-Language Pathologists Delivering Dysphagia Services to Persons with COPD: Analysis of Survey Outcomes

Swallowing impairments co-occur with chronic obstructive pulmonary disease (COPD) leading to aspiration, disease exacerbations, and malnutrition. This pilot survey study aimed to identify current clinical practice patterns for swallowing evaluation and treatment in persons with COPD. A 35-question Qualtrics survey was deployed to medical speech-language pathology (SLP) social media sites and professional boards; flyers were distributed at a professional conference. Forty-eight SLPs completed the study. SLPs routinely include a clinical swallow examination (96%), videofluoroscopic swallowing study (79%), adjunctive respiratory measures (respiratory rate [83%], and pulse oximetry [67%], respiratory-swallow pattern [77%]) but less frequently include fiberoptic endoscopic evaluation of swallowing (23%). Self-reported advanced clinical experience and expert respiratory analysis skills were associated with adjunctive respiratory measure (respiratory rate, pulse oximetry) inclusion during assessment. Compensatory strategy training (77%) is a preferred treatment for dysphagia in COPD; however, respiratory-swallow pattern training and expiratory muscle strength training are increasing in use. SLPs self-report a comprehensive, individualized patient-centered care approach with inclusion of adjunctive respiratory-focused methods in dysphagia evaluation and treatment practice in persons with COPD. Advances in the identification of the integral role of respiratory function in swallowing integrity may be translating to clinical practice methods for dysphagia management in persons with COPD.

Combination of Albumin-Globulin Score and Sarcopenia to Predict Prognosis in Patients With Renal Cell Carcinoma Undergoing Laparoscopic Nephrectomy

We conducted a multicenter clinical study to construct a novel index based on a combination of albumin-globulin score and sarcopenia (CAS) that can comprehensively reflect patients' nutritional and inflammatory status and assess the prognostic value of CAS in renal cell carcinoma (RCC) patients. Between 2014 and 2019, 443 patients from 3 centers who underwent nephrectomy were collected (343 in the training set and 100 in the test set). Kaplan-Meier curves were employed to analyze the impact of albumin-globulin ratio (AGR), albumin-globulin score (AGS), sarcopenia, and CAS on overall survival (OS) and cancer-specific survival (CSS) in RCC patients. Receiver operating characteristic (ROC) curves were used to assess the predictive ability of AGR, AGS, sarcopenia, and CAS on prognosis. High AGR, low AGS, and nonsarcopenia were associated with higher OS and CSS. According to CAS, the training set included 60 (17.5%) patients in grade 1, 176 (51.3%) patients in grade 2, and 107 (31.2%) patients in grade 3. Lower CAS was linked to longer OS and CSS. Multivariate Cox regression analysis revealed that CAS was an independent risk factor for OS (grade 1 vs. grade 3: aHR = 0.08; 95% CI: 0.01-0.58, p = 0.012; grade 2 vs. grade 3: aHR = 0.47; 95% CI: 0.25-0.88, p = 0.018) and CSS (grade 1 vs. grade 3: aHR = 0.12; 95% CI: 0.02-0.94, p = 0.043; grade 2 vs. grade 3: aHR = 0.31; 95% CI: 0.13-0.71, p = 0.006) in RCC patients undergoing nephrectomy. Additionally, CAS had higher accuracy in predicting OS (AUC = 0.687) and CSS (AUC = 0.710) than AGR, AGS, and sarcopenia. In addition, similar results were obtained in the test set. The novel index CAS developed in this study, which reflects patients' nutritional and inflammatory status, can better predict the prognosis of RCC patients.

Low alanine aminotransferase as a risk factor for chronic obstructive pulmonary disease in males

Alanine aminotransferase (ALT) levels reflect skeletal muscle volume and general performance, which are associated with chronic obstructive pulmonary disease (COPD) development and prognosis. This study aimed to investigate ALT levels as a risk factor for COPD development. This 13-year population-based retrospective observational cohort study included 422,452 participants for analysis. We classified groups according to the baseline ALT levels (groups 1-5: ALT (IU/L) < 10; 10-19; 20-29; 30-39; and ≥ 40, respectively). The incidence of COPD was the highest in group 1, decreasing as the group number increased in males, but not in females. The Cox regression analysis in males revealed that a lower ALT level, as a continuous variable, was a significant risk factor for COPD development [univariable, hazard ratio (HR): 0.992, 95% confidence interval (CI): 0.991-0.994; multivariable, HR: 0.998, 95% CI: 0.996-0.999]. In addition, COPD was more likely to develop in the lower ALT level groups (groups 1-4; < 40 IU/L), than in the highest ALT level group (group 5; ≥ 40 IU/L) (univariable, HR: 1.341, 95% CI: 1.263-1.424; multivariable, HR: 1.097, 95% CI: 1.030-1.168). Our findings suggest that males with low ALT levels should be carefully monitored for COPD development.

Low body mass is associated with reduced left ventricular mass in Chinese elderly with severe COPD

There is limited information on the association of body mass index (BMI) with left ventricular (LV) remodeling corresponding to severity of reduced lung function in patients with chronic obstructive pulmonary disease (COPD). Therefore, we investigated whether BMI is associated with cardiac atrial and ventricular dimensions according to severity of lung functional impairment in Chinese COPD elderly. A total of 563 hospitalized COPD patients with lung function impairment and 184 patients with non-COPD (aged 65–92 years) were collected retrospectively in a cross-sectional study in a university affiliated tertiary hospital in China. BMI and cardiac echocardiographic parameters were compared according to severity of lung functional impairment in COPD patients. BMI was 22.9 ± 3.9 kg/m² in COPD patients, 24.0 ± 4.1 kg/m² in non-COPD patients respectively. Reduced BMI, LV mass index, LV wall thickness and left atrial diameter, and dilated right ventricle (RV) existed in COPD patients with severe lung dysfunction as compared the COPD patients with mild to moderate lung functional reduction and non-COPD patients (P < 0.05), while there were no differences in BMI and echocardiographic parameters between the COPD patients with mild to moderate lung functional decline and non-COPD patients (P > 0.05). Logistic regression analysis showed that low BMI (BMI < 18.5 kg/m²) was correlated with reduced LV mass and wall thickness, dilated RV and reduced lung function in the COPD patients with severe lung dysfunction. In conclusion, this study demonstrates that lower BMI is associated not only with dilated RV and impaired pulmonary function, but also it is related to reduced LV mass in Asian COPD elderly with severe lung dysfunction.

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.

Higher serum vitamin D levels are associated with decreased odds of obstructive lung disease in the general population: an NHANES analysis (2007-2008 to 2009-2010)

Background

Obstructive lung disease is a significant cause of morbidity and healthcare burden within the USA. A growing body of evidence has suggested that vitamin D levels can influence the course or incidence of obstructive lung disease. However, there is an insufficient previous investigation of this association.

Study design and methods

We used the National Health and Nutrition Examination Survey (NHANES) cycles 2007–2008 and 2009–2010 spirometry results of individuals aged 40 years and older to assess the association between serum 25-hydroxyvitamin D levels and obstructive lung disease, as defined by the American Thoracic Society using the lower limit of normal. We used stage multivariate survey-logistic regression.

Results

The final model included age, gender, body mass index, pack-years smoking history, season, income-to-poverty ratio and race/ethnicity. In the primary analysis using vitamin D as a continuous variable, there was no association between vitamin D levels and obstructive lung disease. We noted a trend between ‘other Hispanic’ self-identified race and serum vitamin D levels wherein higher levels were associated with higher odds of obstructive lung disease in this ethnicity, but not among other racial or ethnic groups (OR (95% CI)=1.40 (0.98 to 1.99), p=0.06). In a secondary analysis, when vitamin D was measured as a categorical variable, there was a significant association between the highest levels of serum vitamin D levels and lesser odds of obstructive lung disease (OR (95% CI)=0.77 [0.61 to 0.98], p=0.04).

Conclusions

Higher serum vitamin D levels among adults are associated with decreased odds of obstructive lung disease in the general population. Results among non-Mexican Hispanic participants highlight the need for further research in minority populations. More work is needed to address the course and incidence of lung disease in the USA.