Impact of the metabolic syndrome on cardiopulmonary morbidity and mortality in individuals with lung function impairment: a prospective cohort study of the Danish general population

Background

Whether the metabolic syndrome plays a role for the prognosis of individuals with lung function impairment (preserved ratio impaired spirometry (PRISm) or airflow limitation) is unclear. We hypothesised that the metabolic syndrome in individuals with lung function impairment is associated with increased cardiopulmonary morbidity and mortality.

Methods

The Copenhagen General Population Study was initiated in 2003 based on a random sample of white men and women aged 20-100 years drawn from the Danish general population. The risk of ischemic heart disease/heart failure, respiratory disease, and all-cause mortality was analysed with Cox models adjusted for age, sex, current smoking, and asthma during 15 years of follow-up.

Findings

Among 106,845 adults, 86,159 had normal lung function, 6126 had PRISm, and 14,560 had airflow limitation. We observed 10,448 hospital admissions for ischemic heart disease/heart failure, 21,140 for respiratory disease, and 11,125 deaths. Individuals with versus individuals without the metabolic syndrome generally had higher 5-year absolute risk of all outcomes, including within those with normal lung function, mild-moderate-severe PRISm, and very mild-mild-moderate-severe airflow limitation alike. Compared to individuals without the metabolic syndrome and with normal lung function, those with both the metabolic syndrome and severe PRISm had hazard ratios of 3.74 (95% CI: 2.53-5.55; p < 0.0001) for ischemic heart disease/heart failure, 5.02 (3.85-6.55; p < 0.0001) for respiratory disease, and 5.32 (3.76-7.54; p < 0.0001) for all-cause mortality. Corresponding hazard ratios in those with both the metabolic syndrome and severe airflow limitation were 2.89 (2.34-3.58; p < 0.0001) for ischemic heart disease/heart failure, 5.98 (5.28-6.78; p < 0.0001) for respiratory disease, and 4.16 (3.50-4.95; p < 0.0001) for all-cause mortality, respectively. The metabolic syndrome explained 13% and 27% of the influence of PRISm or airflow limitation on ischemic heart disease/heart failure and all-cause mortality.

Interpretation

The metabolic syndrome conferred increased risk of cardiopulmonary morbidity and mortality at all levels of lung function impairment.

Funding

Danish Lung Foundation, Danish Heart Foundation, Capital Region of Copenhagen, and Boehringer Ingelheim. JV is supported by the NIHR Manchester BRC.

Treating chronic diseases without tackling excess adiposity promotes multimorbidity

Few people now reach old age without taking multiple drugs, often attending various clinics, and undergoing secondary or tertiary investigations. Most chronic conditions are, to differing extents, caused or exacerbated by excess adiposity, but weight management is rarely discussed or attempted for patients. Furthermore, progressive symptoms usually attributed to ageing (eg, musculoskeletal pains, fatigue, and breathlessness), and which create considerable health-care demands, can also be attributed to the accumulation of body fat over time. For many symptoms and diseases that are more frequently reported in people with excess adiposity (such as depression), there exist potentially multidirectional, causal relationships that generate a cycle of clinical and social deterioration. There is insufficient research on the effects of effective weight management on these clinically demanding, age and weight-mediated symptoms. Based on current evidence, we suggest that policy makers need to be more proactive in obesity prevention and effective weight management should receive research funding to match the search for novel therapeutics for secondary chronic diseases.

The Association of Fat Mass and Obesity-Associated Gene Polymorphism (rs9939609) on the Body Composition of Older People: Systematic Review

BACKGROUND

Population aging is growing faster than any other age group. Associated with aging, the prevalence of overweight and obesity is a potential risk factor for the development and aggravation of numerous pathologies. A genetic factor often associated with obesity is the Fat mass and obesity associated (FTO) (rs9939609) gene polymorphism, which has been extensively investigated in children, young, and adults. However, few studies have been carried out with the older population. This review aimed to verify the influence of the FTO (rs9939609) gene polymorphism on the body composition of the older population.

METHODS

We conducted a systematic review and Meta-analysis of PubMed, Scielo, and LILACS databases. Statistical analysis for meta-analysis was performed using mean values of Body Mass Index (BMI) and standard deviations.

RESULTS

The results did not show significant differences between FTO genotypes and BMI values (-0.32, 95%CI -0.45 to -0.19, I2 = 0%, p = 0.52). However, 59% of the studies identified some influence on body composition, obesity, or comorbidities.

CONCLUSION

Few publications verify FTO polymorphism effects on specific groups of the older, suggesting a reduction in the influence of this gene in the BMI with advancing age. However, we believe that more controlled studies in older populations should be performed.

Association of body mass index and COPD exacerbation among patients with chronic bronchitis

Background and objective

Chronic obstructive pulmonary disease (COPD) patients with a body mass index (BMI) < 25 kg/m² are prone to develop adverse event of pharmacological treatment for frequent exacerbation. As chronic bronchitis (CB) is one of the strong risk factors of exacerbation, we investigated the associations between BMI and COPD exacerbations in patients with CB.

Methods

Patients with COPD were included from the Korean COPD Subgroup Study (KOCOSS), a multicenter observational cohort study. CB was defined using the St. George’s Respiratory Questionnaire and the participants were categorized according to BMI cut-off of 25 kg/m². Exacerbations during a 1-year follow-up were compared among four groups: non-CB with BMI ≥ 25 kg/m², non-CB with BMI < 25 kg/m², CB with BMI ≥ 25 kg/m², and CB with BMI < 25 kg/m².

Results

Among the 1264 patients with COPD, 451 (35.7%) had CB and 353 (27.9%) had both CB and BMI < 25 kg/m². The COPD exacerbation risk increased across the non-CB with BMI < 25 kg/m², CB with BMI ≥ 25 kg/m², and CB with BMI < 25 kg/m² groups (adjusted incidence rate ratio [95% confidence interval] 1.21 [0.89–1.62], 1.20 [0.77–1.88], and 1.41 [1.02–1.91], respectively, compared to the non-CB with BMI ≥ 25 kg/m² group).

Conclusions

COPD patients having both CB and a BMI < 25 kg/m² are at higher risk of exacerbations. Considering that a BMI < 25 kg/m² often limits treatment options preventing exacerbations, modified guidelines might be needed for non-obese CB patients in Asia.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01957-3.

Risk and impact of chronic cough in obese individuals from the general population

BACKGROUND

Obese individuals may be at higher risk of chronic cough. We investigated the risk and impact of chronic cough in obese individuals from the general population.

METHODS

We recorded chronic cough, body mass index (BMI) and other related clinical conditions in 44 554 adults from the Copenhagen General Population Study. Individuals with asthma and/or chronic obstructive pulmonary disease were excluded (n=10 977). BMI was divided into: underweight (BMI <18.5 kg/m²), normal weight (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²), obese (30.0-34.9 kg/m²) and severely obese (≥35.0 kg/m²).

RESULTS

Among 33 577 adults from the general population, 27 829 (83%) were non-obese and 5748 (17%) were obese. Compared with individuals with normal weight, multivariable adjusted ORs for chronic cough risk were 1.4 (95% CI 1.2 to 1.6) in overweight, 1.9 (95% CI 1.7 to 2.2) in obese and 2.6 (95% CI 2.1 to 3.2) in severely obese individuals. Mediation analyses showed that chronic cough due to obesity was up to 23% mediated by gastro-oesophageal reflux disease (GERD). Other mediators included low vegetable intake with 10% and occupational exposure with 8%. Among obese individuals, those with versus without chronic cough had worse accompanying respiratory symptoms, more often comorbidities including GERD and diabetes, greater healthcare utilisations, lower lung function and higher blood inflammation (all p<0.05).

CONCLUSION

There is dose-response relationship between BMI and chronic cough, and chronic cough risk is twofold to threefold higher in obese individuals from the general population. This increased risk was partly mediated by GERD, low vegetable intake and occupational exposure, supporting that there may be benefit to gain by ameliorating some of these factors in obese individuals with chronic cough.

Risk factors for exacerbations and pneumonia in patients with chronic obstructive pulmonary disease: a pooled analysis

Background

Patients with chronic obstructive pulmonary disease (COPD) are at risk of exacerbations and pneumonia; how the risk factors interact is unclear.

Methods

This post-hoc, pooled analysis included studies of COPD patients treated with inhaled corticosteroid (ICS)/long-acting β₂ agonist (LABA) combinations and comparator arms of ICS, LABA, and/or placebo. Backward elimination via Cox’s proportional hazards regression modelling evaluated which combination of risk factors best predicts time to first (a) pneumonia, and (b) moderate/severe COPD exacerbation.

Results

Five studies contributed: NCT01009463, NCT01017952, NCT00144911, NCT00115492, and NCT00268216. Low body mass index (BMI), exacerbation history, worsening lung function (Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage), and ICS treatment were identified as factors increasing pneumonia risk. BMI was the only pneumonia risk factor influenced by ICS treatment, with ICS further increasing risk for those with BMI <25 kg/m². The modelled probability of pneumonia varied between 3 and 12% during the first year. Higher exacerbation risk was associated with a history of exacerbations, poorer lung function (GOLD stage), female sex and absence of ICS treatment. The influence of the other exacerbation risk factors was not modified by ICS treatment. Modelled probabilities of an exacerbation varied between 31 and 82% during the first year.

Conclusions

The probability of an exacerbation was considerably higher than for pneumonia. ICS reduced exacerbations but did not influence the effect of risks associated with prior exacerbation history, GOLD stage, or female sex. The only identified risk factor for ICS-induced pneumonia was BMI <25 kg/m². Analyses of this type may help the development of COPD risk equations.

The COPD Comorbidome in the Light of the Degree of Dyspnea and Risk of Exacerbation

The BODE group designed a bubble chart, analogous to the solar system, which depicts the prevalence of each disease and its association with mortality and called it a "comorbidome". Although this graph was used to represent mortality and, later, the risk of needing hospital admission, it was not applied to visualize the association between a set of comorbidities and the categories of the GOLD 2017 guidelines, neither according to the degree of dyspnea nor to the risk of exacerbation. For the purpose of knowing to which extent each comorbidity associates with each of the two conditions-most symptomatic group (groups B and D) and highest risk of exacerbation (groups C and D)-we performed a analysis based on the comorbidome. 439 patients were included. Cardiovascular comorbidity (especially cardiac and renal disease) is predominantly observed in patients with a higher degree of dyspnea, whereas bronchial asthma and stroke occur more frequently in subjects at higher risk of exacerbation. This is the first time that the comorbidome is presented based on the categories of the GOLD 2017 document, which we hope will serve as a stimulus for scientific debate.

Impact of BMI on exacerbation and medical care expenses in subjects with mild to moderate airflow obstruction

Background and objective

The rate of obesity is increasing in Asia, but the clinical impact of body mass index (BMI) on the outcome of chronic obstructive pulmonary disease (COPD) remains unknown. We aimed to assess this impact while focusing on the risk of exacerbation, health-care utilization, and medical costs.

Methods

We examined 43,864 subjects registered in the Korean National Health and Nutrition Examination Survey (KNHANES) database from 2007 to 2012, and linked the data of COPD patients who had mild to moderate airflow obstruction (n = 1,320) to National Health Insurance (NHI) data. COPD was confirmed by spirometry. BMI was used to stratify patients into four categories: underweight (BMI <18.5 kg/m²), normal range (18.5–22.9 kg/m²), overweight (23–24.9 kg/m²), and obese (≥25 kg/m²).

Results

Of the 1,320 patients with COPD with mild to moderate airflow obstruction, 27.8% had a BMI ≥25 kg/m². Compared with normal-weight patients, obese patients tended to experience fewer exacerbations (incidence rate ratio [IRR] 0.88; 95% CI 0.77–0.99; P = 0.04), although this association was not significant in a multivariable analysis. COPD-related health-care utilization and medical expenses were higher among underweight patients than the other groups. After adjustment, the risk of COPD-related hospitalization was highest among underweight and higher among overweight patients vs normal-weight patients (adjusted IRRs: 7.12, 1.00, 1.26, and 1.02 for underweight, normal, overweight, and obese groups, respectively; P = 0.01).

Conclusion

Decreased weight tends to negatively influence prognosis of COPD with mild to moderate airflow obstruction, whereas higher BMI was not significantly related to worse outcomes.

Impact of overweight and obesity on acute exacerbations of COPD - subgroup analysis of the Taiwan Obstructive Lung Disease cohort

Purpose

A low body mass index (BMI) is a poor prognostic marker of acute exacerbations and mortality in patients with COPD. However, the impact of overweight and obesity on COPD-related outcomes is uncertain. The aim of this study was to examine whether a high BMI is associated with the frequent exacerbator phenotype (≥2/year) in Taiwanese patients with COPD.

Patients and methods

Data were obtained from the Taiwan Obstructive Lung Disease study, a retrospective, observational nationwide survey of COPD patients conducted at 12 hospitals in Taiwan. Multivariate logistic regression models were used to explore the association between BMI and other factors with the frequency of COPD exacerbations in these patients.

Results

Among the whole study cohort (n=1,096), 735 (67.1%) had no exacerbations and 148 (13.5%) were frequent exacerbators in the previous year. The BMI values of the patients with 0, 1, and ≥2 exacerbations were 23.6, 23.5, and 22.6 kg/m², respectively. In all, 256 (23.4%) and 196 (17.9%) patients were overweight (27 kg/m² > BMI ≥24 kg/m²) and obese (BMI ≥27 kg/m²), respectively. Even after adjusting for multiple factors, overweight and obesity were associated with the frequency of exacerbations (odds ratio [95% confidence interval] 0.49 [0.28–0.87, P=0.015] and 0.49 [0.26–0.94, P=0.033], respectively).

Conclusion

Our results suggest that overweight and obesity are associated with a lower frequency of COPD exacerbations in Taiwan.

Metabolic Disorder in Chronic Obstructive Pulmonary Disease (COPD) Patients: Towards a Personalized Approach Using Marine Drug Derivatives

Metabolic disorder has been frequently observed in chronic obstructive pulmonary disease (COPD) patients. However, the exact correlation between obesity, which is a complex metabolic disorder, and COPD remains controversial. The current study summarizes a variety of drugs from marine sources that have anti-obesity effects and proposed potential mechanisms by which lung function can be modulated with the anti-obesity activity. Considering the similar mechanism, such as inflammation, shared between obesity and COPD, the study suggests that marine derivatives that act on the adipose tissues to reduce inflammation may provide beneficial therapeutic effects in COPD subjects with high body mass index (BMI).