The gender-specific adverse association of polycyclic aromatic hydrocarbons on skeletal muscle mass and strength in the general adults and the possible mechanisms in experimental rats.

Whether polycyclic aromatic hydrocarbons (PAHs) exposure is associated with muscle mass and muscle strength has been scantly investigated. The cross-sectional associations of urinary PAH metabolites with appendicular skeletal muscle mass and hand grip strength in adults were first investigated in the National Health and Nutrition Examination Survey (NHANES). Laboratory study was further carried out to examine the effect of PAHs on skeletal muscle mass and strength. 2742 and 2462 US adults were finally analyzed for muscle mass and muscle strength, respectively. In male participants, urinary PAH metabolites were found to show an inverse relationship with muscle mass and grip strength. In female participants, no significant relationship was found between urinary PAH metabolites with muscle mass or grip strength. In male Sprague-Dawley (SD) rats, administration of B [a]P induced muscle atrophy when compared with the control. However, muscle mass and strength were not significantly altered in female rats. The variations in muscle morphology parameters were accompanied by significant decrease in plasma testosterone levels in the B [a]P-treated male rats. Testosterone co-treatment significantly mitigated B [a]P mediated damages in skeletal muscle in male rats. The results of the present study indicate that there may be a gender-specific causal relationship between the PAHs and muscle atrophy.

Exposure to phthalates is associated with grip strength in US adults.

The potential association of exposure to phthalates with muscle strength was reported in previous animal experiments. However, their association was rarely directly investigated in general populations. Thus, we aimed to ascertain the association of exposure to phthalates with grip strength using cross-sectional analysis which included 2436 individuals aged ≥ 20 years from the National Health and Nutrition Examination Survey (NHANES) during 2011-2014. The multivariable linear regression models were performed with the adjustment of related covariates. The results suggested that a one-unit increase in log-transformed phthalate metabolites (µg/g creatinine) was inversely associated with grip strength, including Mono-(2-ethyl)-hexyl phthalate (ß: -2.727 kg, 95% CI: -3.452, -2.002), Mono-(2-ethyl-5-hydroxyhexyl) phthalate (ß: -3.721 kg, 95% CI: -4.836, -2.607), Mono-(2-ethyl-5-oxohexl) phthalate (ß: -4.669 kg, 95% CI: -5.761, -3.577), Mono-2-ethyl-5-carboxypentyl phthalate (ß: -4.756 kg, 95% CI: -5.957, -3.554), Mono-carboxyoctyl phthalate (ß: -1.324 kg, 95% CI: -2.412, -0.235), Mono-carboxynonyl phthalate (ß: -2.036 kg, 95% CI: -3.185, -0.886), Mono-benzyl phthalate (ß: -2.940 kg, 95% CI: -3.853, -2.026), Mono-n-butyl phthalate (ß: -2.100 kg, 95% CI: -3.474, -0.726), Mono-isobutyl phthalate (ß: -2.982 kg, 95% CI: -4.331, -1.633), and Mono-ethyl phthalate (ß: -1.709 kg, 95% CI: -2.368, -1.050). In subgroup analyses, the associations remained largely unchanged when the samples were stratified by gender and age; However they became ambiguous among underweight subjects when the samples were stratified by BMI status. Overall, exposure to phthalates was inversely associated with grip strength among US adults, regardless of their genders and ages. The suggestive potential BMI status-specific effects of phthalates on grip strength were observed.

Bone mineral density and osteoporosis in relation to all-cause and cause-specific mortality in NHANES: A population-based cohort study.

OBJECTIVE: The majority of the published studies ascertaining the relationships between low bone mineral density (BMD) and mortality highlighted the elderly population with limited sample size. Our study aimed to ascertain the relationships in general population. METHODS: This study ascertained the relationships between BMD levels in femur and lumbar spine with all-cause and cause-specific mortality in the National Health and Nutrition Examination Survey (NHANES) (n = 15,076, mean age 48.6 years). Cox proportional hazards models were adopted to calculate the hazard ratios (HR) and the corresponding 95% confidence intervals (CIs) for mortality. RESULTS: During a 6.8-year median follow-up, 1216 men and women in the cohort died. There was a higher risk of all-cause mortality among participants with osteoporosis compared with normal in the regions of total femur (HR = 1.36, 95% CI = 1.07-1.73), femur neck (HR = 1.41, 95% CI = 1.11-1.78), intertrochanter (HR = 1.34, 95% CI = 1.05-1.72), as well as overall (HR = 1.36, 95% CI = 1.09-1.69). Non-linear dose-response analyses showed a statistically significant L-shaped association for all-cause mortality with BMD increment in the regions of total femur, femur neck, trochanter, and intertrochanter. The protective role of higher BMD level in femur for decreased risk of cancer mortality and heart diseases mortality was more evident in male participants and female participants, respectively. CONCLUSIONS: In summary, our results revealed that maintaining normal BMD is critical to lower the risk of mortality. The association between higher BMD level in femur and decreased risk of cancer as well as heart diseases mortality varies by gender.

Associations of urinary levels of phenols and parabens with osteoarthritis among US adults in NHANES 2005-2014.

Phenols and parabens are two major classes of endocrine-disrupting compounds (EDCs) that may be related to multiple human diseases. However, there has been no studies examining the association between phenols as well as parabens and osteoarthritis (OA). We assessed the link between urinary concentrations of triclosan (TCS), benzophenone-3 (BP-3), bisphenol A (BPA), and parabens with OA based on the data collected from National Health and Nutrition Examination Survey in multivariable logistic regression models. Among all the 7114 participants included, the weighted percentage of OA was 12.11% (n = 807). Compared with participants at tertile 1, those at tertile 2 of urinary BP-3, and tertile 3 of urinary BP-3 were more likely to show increased OA prevalence in a fully adjusted model, with odd ratio (OR) as 1.34 [95% confidence interval (CI): 1.01-1.78], 1.55 (95 CI%: 1.17-2.06), and 1.66 (95 CI%: 1.23-2.24), respectively. In subgroup analyses stratified by potential confounders, various subgroups remained to show statistically significant positive association between urinary BP-3 and OA prevalence. Otherwise, we observed no statistically significant associations between urinary TCS, BPA or parabens with OA. In conclusion, this serves as the first study in which we found that the urinary concentration of BP-3 was positively correlated to prevalence of OA among the US population.

Relationship between polycyclic aromatic hydrocarbons and rheumatoid arthritis in US general population, NHANES 2003-2012.

The purpose of this study was to explore the association between urinary concentrations of polycyclic aromatic hydrocarbon (PAH) metabolites and the prevalence of rheumatoid arthritis (RA). Cross-sectional data were analyzed from the National Health and Nutrition Examination Survey (NHANES) 2003-2012 using levels of nine monohydroxylated urinary PAH metabolites as exposure. Multivariable logistic regression was used to examine the association between urinary biomarkers of PAHs and RA. All of the models were adjusted for age, sex, race, education level, marital status, smoking, BMI, physical activity, energy, diabetes, and survey cycle. Ultimately, 6,072 adults (3,108 men and 2,964 women) 20 years of age or older were analyzed. In the quartile analyses, compared with the lowest quartile, increased RA prevalence was observed in the participants with the highest quartile of 2-hydroxynapthalene (OR = 1.89, 95% CI = 1.28-2.78), 3-hydroxyfluorene (OR = 1.55, 95% CI = 1.07-2.25), 2-hydroxyfluorene (OR = 1.51, 95% CI = 1.02-2.24), 3-hydroxyphenanthrene (OR = 1.50, 95% CI = 1.09-2.07), and 9-hydroxyfluorene (OR = 1.60, 95% CI = 1.10-2.33) in a fully adjusted model, respectively. In the subgroup analysis of current smokers, compared with the participants with lower urinary PAH scores, those with higher scores had a dramatically increased prevalence of RA (OR = 15.46, 95% CI = 3.11-76.75) in the adjusted model. There was a significant interaction between all of the urinary PAH metabolite levels and smoking status in the relationship with RA (P < 0.05). High levels of urinary PAH metabolites are positively associated with RA prevalence in the US general population. PAH exposure and smoking may potentially interact to increase the prevalence of RA. Further prospective studies are needed to clarify the possible effect of PAHs on RA.

Association Between Urinary Triclosan With Bone Mass Density and Osteoporosis in US Adult Women, 2005‒2010.

CONTEXT: Laboratory studies have demonstrated that triclosan (TCS) can cause significant interstitial collagen accumulation and an increase in trabecular bone. However, little is known about the relationship between TCS exposure and human bone health. METHODS: We used 2005 to 2010 National Health and Nutrition Examination Survey data to examine the association between urinary TCS concentration and bone mineral density (BMD) and osteoporosis in US adult women aged ≥20 years. After inclusion and exclusion, 1848 women were analyzed. RESULTS: After adjustment for other covariates, we observed significant associations between tertile 3 of TCS concentration and lower BMD in regions of the total femur (ß = -0.016; 95% CI = -0.032, -0.000), intertrochanteric region (ß = -0.022; 95% CI = -0.042, -0.002), and lumbar spine (ß = -0.014; 95% CI = -0.029, 0.001), respectively, relative to tertile 1. Compared with women at tertile 1, those at tertile 3 were more likely to have increased prevalence of osteoporosis in the intertrochanteric region (OR = 2.464; 95% CI = 1.190, 5.105). CONCLUSION: This epidemiological study investigated the association between urinary TCS concentration and BMD and osteoporosis in US adult women. We found urinary TCS concentration was negatively associated with BMD and was positively associated with the prevalence of osteoporosis. The evidence was stronger in postmenopausal women than in premenopausal women. Future prospective studies are needed to validate these findings.

Association between total sleep time and all cancer mortality: non-linear dose-response meta-analysis of cohort studies.

OBJECTIVE: Appropriate total sleep time is reported to be associated with several important health outcomes. However, the relationship between total sleep time and all cancer mortality is not well defined because of inconsistent results from published studies, and no dose-response meta-analysis was performed to evaluate the exact dose-response relationship. METHODS: We conducted a literature search of PubMed and Web of Science to identify all relevant epidemiological studies published before August 9, 2018. We performed categorical and non-linear dose-response meta-analyses to quantify the association between total sleep time and all cancer mortality. RESULTS: Finally, we included 14 cohort studies in the present meta-analyses enrolling 866,877 participants with 43,021 cancer deaths. We found that total sleep time less than seven hours was not significantly associated with increased risk of all cancer mortality [relative risk (RR) = 1.02; 95% confidence interval (CI) = 0.99-1.05]. However, four to five hours total sleep time was related to an 8% increased risk of all cancer mortality (RR = 1.08; 95% CI = 1.02-1.13) in dose-response meta-analysis. Furthermore, long total sleep time (≥8 hours) was weakly associated with all cancer mortality (RR = 1.05; 95% CI = 1.02-1.08). However, the increment in total sleep time longer than nine hours was notably associated with an increased risk of cancer mortality. CONCLUSION: The current meta-analysis provides evidence of a positive association between total sleep time of four to five hours and total sleep time longer than eight hours with the risk of all cancer mortality among the general population. Additional studies are needed to establish causality.

Long noncoding RNA CCAT1 polymorphisms are associated with the risk of colorectal cancer.

Colorectal cancer associated transcript 1 (CCAT1) is a novel long noncoding RNA, whose overexpression is evident in both early phase of tumorigenesis and later disease stages in colorectal cancer (CRC). No study has explored the relationship between CCAT1 polymorphisms and CRC risk. In the present study, a case-control study was conducted to investigate the association between CCAT1 polymorphisms and CRC risk in Chinese population. We identified that CCAT1 rs67085638 polymorphism was associated with an increased risk of CRC (OR = 1.72, 95%CI = 1.14-2.58, P = 0.009 in heterozygote codominant model; OR = 1.67, 95%CI = 1.13-2.47, P = 0.010 in dominant model). Moreover, CCAT1 rs7013433 polymorphism was associated with late clinical stage (OR = 1.82, 95%CI = 1.16-2.86, P = 0.009 in heterozygote codominant model; OR = 1.72, 95%CI = 1.13-2.63, P = 0.012 in dominant model). Our finding proposed a link between CCAT1 polymorphisms with CRC risk as well as different clinical stages.