Waist to Height Ratio and Metabolic Syndrome as lung dysfunction predictors

Relationship between commonly defined metabolic health phenotypes and obesity with lung function in a working population: A cross-sectional study

BACKGROUND

Four phenotypes relate metabolism and obesity: metabolically healthy (MHO) and unhealthy (MUO) people with obesity and metabolically healthy (MHNO) and unhealthy (MUNO) people without obesity. No studies have addressed the association between these categories and lung function in the working population.

OBJECTIVES

The aim was to determine the relationship of phenotypes to lung ageing as measured by lung age and its relationship to lung dysfunction.

METHODS

A descriptive cross-sectional study was conducted in a working population. The outcome variable was lung function assessed by lung age. The four phenotypes of obesity and metabolic health (MHNO, MHO, MUO and MUNO) were determined using NCEP-ATP III criteria. Lung dysfunctions were classified into restrictive, obstructive, and mixed patterns.

RESULTS

The mean age of the participants was 43.7 years, ranging from 18 to 67 years. Of the 1860 workers, 51.3 % were women. The prevalences found were 71.4 %, 12 %, 10.6 % and 6 % for MHNO, MUO, MHO, and MUNO, respectively. MHO (β = 0.66; p = 0.591) was not associated with increased lung ageing compared with MHNO, but MUO (β = 7.1; p < 0.001) and MUNO (β = 6.6; p < 0.001) were. Concerning pulmonary dysfunctions, MUNO (OR = 1.93; p < 0.001) and MUO (OR = 2.91; p < 0.001) were found to be related to the presence of a restrictive pattern, and MUNO (OR = 2.40; p = 0.028) to the mixed pattern.

CONCLUSION

The results show that metabolic abnormalities, not obesity, are responsible for premature lung ageing and, therefore, lung function decline. In our study, having obesity without metabolic abnormality was not significantly associated with the presence of dysfunctional respiratory patterns.

The relationship between cardiometabolic index and pulmonary function among U.S. adults: insights from the National Health and Nutrition Examination Survey (2007-2012)

BACKGROUND

Previous findings have revealed that disorders of lipid metabolism may be a risk factor for pulmonary function damage; however, the combined effect of dyslipidemia and central obesity on pulmonary function is unclear. The cardiometabolic index (CMI) is a composite of serum lipids (triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C)) and visceral fat parameters (waist-to-height ratio (WHtR)). This research aimed to investigate the link between CMI and pulmonary function, employing large-scale demographic data sourced from the National Health and Nutrition Examination Survey (NHANES) database.

METHODS

This cross-sectional study used data involving 4125 adults aged 20 and above collected by NHANES between 2007 and 2012. We defined CMI as the exposure variable and measured outcomes using forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC to evaluate pulmonary function. Weighted multiple linear regression models and subgroup analyses were employed to investigate separate relationships between CMI and pulmonary function. In addition, to investigate variations across different strata and evaluate the robustness of the findings, interaction tests and sensitivity analyses were conducted.

RESULTS

Results from the weighted multiple linear regression analysis indicated a unit increase in log2-CMI was associated with a reduction of 82.63 mL in FEV1 and 112.92 mL in FVC. The negative association remained significant after transforming log2-CMI by quartile (Q). When the log2-CMI level reached Q4, β coefficients (β) were -128.49 (95% CI: -205.85, -51.13), -169.01 (95% CI: -266.72, -71.30), respectively. According to the interaction test findings, the negative association linking log2-CMI with FEV1 and FVC persists regardless of confounding factors including age, gender, BMI, physical activity (PA), and smoking status. A subsequent sensitivity analysis provided additional confirmation of the stability and reliability of the results. For females, the inflection points for the nonlinear relationships between log2-CMI and FEV1, as well as log2-CMI and FVC, were identified at 2.33 and 2.11, respectively. While in males, a consistent negative association was observed.

CONCLUSIONS

Our findings suggest that higher CMI is associated with lower FEV1 and FVC. CMI may serve as a complementary consideration to the assessment and management of pulmonary function in clinical practice.

Association between viral hepatitis and metabolic syndrome in lung function impairment: A Taiwan community-based study

OBJECTIVES

Metabolic syndrome (MetS) and hepatitis C virus (HCV) are associated with a higher risk of impaired pulmonary function (iPF). This study aimed to investigate the relationships among MetS, iPF, and viral hepatitis.

METHODS

This community-based study enrolled participants undergoing annual health check-ups in southern Taiwan between March and December 2019. We performed multivariable logistic regression analyses adjusted for demographics and characteristics to identify the factors associated with iPF.

RESULTS

A total of 2337 participants completed examinations, of whom 928 (39.7%) had iPF. The participants with iPF were elderly (68.8  ±  12.8 years old) and predominately female (63%). MetS increased the risk of iPF (odds ratio (OR) 1.51, 95% confidence interval (CI) 1.27-1.81, p < 0.001). Beyond age (OR 1.03, 95% CI 1.02-1.04) and smoking (OR 1.309, 95% CI 1.004-1.705), female sex (OR 0.74, 95% CI 0.59-0.93) and high education level (OR 0.96, 95% CI 0.94-0.98, p < 0.001) protected against iPF. HCV was not significantly associated with iPF (OR 1.17, 95% CI 0.90-1.52, p  =  0.235) in multivariable analysis. MetS was associated with a higher risk of iPF in the non-HBV/HCV group (OR 1.86, 95% CI 1.54-2.26) and HBV alone group (OR 3.44, 95% CI 1.89-6.28), but not in the HCV alone group (OR 1.02, 95% CI 0.64-1.62).

DISCUSSION

MetS was an independent predictor of iPF, especially the restrictive type, and had different effects in the HBV/non-viral hepatitis and HCV groups. Female sex and education were inversely associated with iPF.

Comparison of the predictive value of anthropometric indicators for the risk of benign prostatic hyperplasia in southern China

This study aimed to compare the predictive value of six selected anthropometric indicators for benign prostatic hyperplasia (BPH). Males over 50 years of age who underwent health examinations at the Health Management Center of the Second Xiangya Hospital, Central South University (Changsha, China) from June to December 2020 were enrolled in this study. The characteristic data were collected, including basic anthropometric indices, lipid parameters, six anthropometric indicators, prostate-specific antigen, and total prostate volume. The odds ratios (ORs) with 95% confidence intervals (95% CIs) for all anthropometric parameters and BPH were calculated using binary logistic regression. To assess the diagnostic capability of each indicator for BPH and identify the appropriate cutoff values, receiver operating characteristic (ROC) curves and the related areas under the curves (AUCs) were utilized. All six indicators had diagnostic value for BPH (all P ≤ 0.001). The visceral adiposity index (VAI; AUC: 0.797, 95% CI: 0.759-0.834) had the highest AUC and therefore the highest diagnostic value. This was followed by the cardiometabolic index (CMI; AUC: 0.792, 95% CI: 0.753-0.831), lipid accumulation product (LAP; AUC: 0.766, 95% CI: 0.723-0.809), waist-to-hip ratio (WHR; AUC: 0.660, 95% CI: 0.609-0.712), waist-to-height ratio (WHtR; AUC: 0.639, 95% CI: 0.587-0.691), and body mass index (BMI; AUC: 0.592, 95% CI: 0.540-0.643). The sensitivity of CMI was the highest (92.1%), and WHtR had the highest specificity of 94.1%. CMI consistently showed the highest OR in the binary logistic regression analysis. BMI, WHtR, WHR, VAI, CMI, and LAP all influence the occurrence of BPH in middle-aged and older men (all P ≤ 0.001), and CMI is the best predictor of BPH.

Impact of Body Composition Parameters on Lung Function in Athletes

Background: Given the potential risk of unhealthy weight management, the monitoring of body composition in athletes is advised. However, limited data reveal how body composition measurements can benefit athlete health and, in particular, respiratory function. The aim of this study is to evaluate the impact of body composition on pulmonary function in a population of adult athletes. Methods: Data from 435 competitive adult athletes regarding body compositions parameters and spirometry are retrospectively analyzed. Results: Our study population consists of 335 males and 100 female athletes. Muscle mass and fat-free mass are significantly and positively associated with forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) in the male and female population, while waist-to-height ratio is negatively associated with FEV1, FVC, and FEV1/FVC in the male population. In multivariable analysis, muscle mass and fat-free mass show significant association with FEV1 and FVC in both males and females (p < 0.05), and waist-to-height ratio is significantly and inversely associated with FEV1 and FVC in males (p < 0.05). Conclusions: Fat-free mass and muscle mass are positively and independently associated with FEV1 and FVC in athletes of both genders, and waist-to-height ratio is inversely associated with FEV1 and FVC only among male athletes. These findings suggest that body composition in athletes may be helpful in monitoring respiratory function.

Dynamic Metabolic Risk Profiling of World Trade Center Lung Disease: A Longitudinal Cohort Study

Rationale: Metabolic syndrome (MetSyn) increases the risk of World Trade Center (WTC) lung injury (LI). However, the temporal relationship of MetSyn, exposure intensity, and lung dysfunction is not well understood. Objective: To model the association of longitudinal MetSyn characteristics with WTC lung disease to define modifiable risk. Methods: Firefighters, for whom consent was obtained (N = 5,738), were active duty on September 11, 2001 (9/11). WTC-LI (n = 1,475; FEV₁% predicted <lower limit of normal [LLN]) and non-WTC-LI (n = 4,263; FEV₁% predicted ⩾LLN at all exams) was the primary outcome, and FVC% predicted <LLN and FEV₁/FVC <0.70 were secondary outcomes. We assessed 1) the effect of concurrent MetSyn on longitudinal lung function by linear mixed models, 2) the temporal effect of MetSyn and exposure by Weibull proportional hazards, 3) the effects of MetSyn's rate of change by two-stage models, and 4) the nonlinear joint effect of longitudinal MetSyn components by a partially linear single-index model (PLSI). Measurements and Main Results: WTC-LI cases were more often ever-smokers, arrived in the morning (9/11), and had MetSyn. Body mass index ⩾30 kg/m² and high-density lipoprotein <40 mg/dl were most contributory to concurrent loss of FEV₁% predicted and FVC% predicted while conserving FEV₁/FVC. Body mass index ⩾30 kg/m² and dyslipidemia significantly predicted WTC-LI, FVC% predicted <LLN in a Weibull proportional hazards model. Dynamic risk assessment of WTC-LI on the basis of MetSyn and exposure showed how reduction of MetSyn factors further reduces WTC-LI likelihood in susceptible populations. PLSI demonstrates that MetSyn has a nonlinear relationship with WTC lung disease, and increases in cumulative MetSyn risk factors exponentially increase WTC-LI risk. An interactive metabolic-risk modeling application was developed to simplify PLSI interpretation. Conclusions: MetSyn and WTC exposure contribute to the development of lung disease. Dynamic risk assessment may be used to encourage treatment of MetSyn in susceptible populations. Future studies will focus on dietary intervention as a disease modifier.