Combined association of urinary volatile organic compounds with chronic bronchitis and emphysema among adults in NHANES 2011-2014: The mediating role of inflammation.

Evidence on the association of volatile organic compounds (VOCs) with chronic bronchitis (CB) and emphysema is spare and defective. To evaluate the relationship between urinary metabolites of VOCs (mVOCs) with CB and emphysema, and to identify the potential mVOC of paramount importance, data from NHANES 2011-2014 waves were utilized. Logistic regression was conducted to estimate the independent association of mVOCs with respiratory outcomes. Least absolute shrinkage and selection operator (LASSO) regression was performed to screen a parsimonious set of CB- and emphysema-relevant mVOCs that were used for further co-exposure analyses of weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR). Mediation analysis was employed to detect the mediating role of inflammatory makers in such associations. In single exposure analytic model, nine mVOCs were individually and positively associated with CB, while four mVOCs were with emphysema. In WQS regression, positive association between LASSO selected mVOCs and CB was identified (OR = 1.82, 95% CI: 1.25 to 2.69), and N-acetyl-S-(4-hydroxy-2-butenyl)-l-cysteine (MHBMA3) weighted the highest. Results from BKMR further validated such combined association and the significance of MHBMA3. As for emphysema, significantly positive overall trend of mVOCs was only observed in BKMR model and N-acetyl-S-(N-methylcarbamoyl)-l-cysteine (AMCC) contributed most to the mixed effect. White blood cell count (WBC) and lymphocyte number (LYM) were mediators in the positive pattern of mVOCs mixture with CB, while association between mVOCs mixture and emphysema was significantly mediated by LYM and segmented neutrophils num (NEO). This study demonstrated that exposure to VOCs was associated with CB and emphysema independently and combinedly, which might be partly speculated that VOCs were linked to activated inflammations. Our findings shed novel light on VOCs related respiratory illness, and provide a new basis for the contribution of certain VOCs to the risk of CB and emphysema, which has potential public health implications.

Urinary polyaromatic hydrocarbons are associated with adult emphysema, chronic bronchitis, asthma, and infections: US NHANES, 2011-2012.

Links between environmental chemicals and human health have emerged over the last few decades, but the effects from polyaromatic hydrocarbons were less studied, compared to other commonly known environmental chemicals such as heavy metals, phthalates, arsenic, phenols, pesticides, etc. Therefore, the aim of the study was to examine the relationships of urinary polyaromatic hydrocarbons and adult respiratory health conditions using a large human sample in a national and population-based setting in recent years. Data were retrieved from United States National Health and Nutrition Examination Surveys, 2011-2012 including demographics, self-reported health conditions, and urinary polyaromatic hydrocarbons. Statistical analyses including chi-square test, t test, and survey-weighted logistic regression modeling were performed. Of 5560 American adults aged 20-80, urinary 2-hydroxyfluorene and 3-hydroxyfluorene were positively associated with emphysema (OR, 1.60, 95 % CI 1.26 to 2.03, P = 0.001 and OR, 1.42, 95 % CI 1.15 to 1.77, P = 0.003, respectively) and chronic bronchitis (OR, 1.42, 95 % CI 1.04 to 1.94, P = 0.031 and OR, 1.40, 95 % CI 1.03 to 1.91, P = 0.036, respectively), while 2-hydroxynaphthalene (2-naphthol) was likely to be borderline associated with emphysema and chronic bronchitis. Conversely, urinary 1-hydroxyphenanthrene, 3-hydroxyphenanthrene, 1-hydroxypyrene, and 4-hydroxyphenanthrene were inversely associated with asthma and infections. Urinary polyaromatic hydrocarbons are associated with adult respiratory health conditions, although the causality cannot be established. For future research, studies using large human sample across regions to longitudinally monitor would be suggested. For practice and policy-making, regulation on minimizing polyaromatic hydrocarbons exposure to protect respiratory health might need to be considered in future health and environmental policies and intervention programs.

[Muscle catabolism in patients with chronic obstructive pulmonary disease]. / Catabolismo muscular en pacientes con enfermedad pulmonar obstructiva crónica.

BACKGROUND AND OBJECTIVES: Chronic obstructive pulmonary disease (COPD) is accompanied by muscle involvement. Pseudouridine, a catabolite of RNA, has been used in other conditions to assess muscle catabolism. We have examined the excretion of pseudouridine in patients with different stages of COPDs evolution. SUBJECTS AND METHODS: We have defined four population groups: control group (without disease), chronic bronchitis group, emerging COPD group, and advanced COPD group. Pseudouridine was determined by high performance liquid chromatography, RESULTS: Pseudouridine extraction (pseudouridine/creatinine ratio) was (mean+19.9 (6.6) µmol/mmol in control group and was found to be very increased in all the patients with pulmonary condition: chronic bronchitis, 44.1 (60.75) µmol/mmol, 81.6 (56.8) µmol/mmol in emerging COPD group and 140.1 (68) µmol/mmol in advanced COPD for all the comparisons with normal subjects and among patients with lung disease). Age and gender did not affect pseudouridine excretion. CONCLUSIONS: The urinary excretion of pseudouridine is increased in chronic bronchitis and COPD and is related to disease stage. Its excretion is independent of age and gender.