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The global use of >3000 per-and polyfluoroalkyl substances (PFASs) has given rise to chemical regulatory action. However, limited information exists regarding current and historical emissions for the majority of PFASs under currently implemented regulations. This study employed suspect and nontarget screening to examine the temporal trends of legacy and unregulated PFASs in liver of the endangered beluga whale (Delphinapterus leucas) population from the St. Lawrence Estuary in Canada collected from 2000 to 2017. A suite of 54 PFASs were tentatively identified, and were grouped into nine structurally distinct classes. Single-hydrogenated perfluoro carboxylic acids (H-PFCAs), single-hydrogenated sulfonamides (H-Sulfonamides), as well as other select sulfonamides were detected for the first time in wildlife. Greater concentrations of the majority of PFASs were determined in newborns and juveniles than in adults, suggesting effective placental and lactational transfer of PFASs. Legacy per-and polyfluoroalkyl acids and perfluorooctane sulfonamide in beluga whale liver were found to significantly decrease in concentration between 2000 and 2017, while unregulated short-chain PFAS alternatives, H-PFCAs, and odd-chain FTCAs were found to increase over time. The implementation of suspect and nontarget screening revealed class-specific temporal trends of PFASs in SLE beluga whales, and supported continuous emissions of unregulated PFASs into the environment.

Several meta-analyses of observational studies have been performed to examine the association between general obesity, as measured by body mass index (BMI), and lung cancer. These meta-analyses suggest an inverse relation between high BMI and this cancer. In contrast to general obesity, abdominal obesity appears to play a role in the development of lung cancer. However, the association between abdominal obesity (as measured by waist circumference (WC) (BMI adjusted) and waist to hip ratio (WHR)) and lung cancer is not fully understood due to sparse available evidence regarding this association. PubMed and Web of Science databases were searched for studies assessing the association between abdominal obesity and lung cancer up to October 2016. The summary relative risks (RRs) with 95% confidence intervals (CIs) were calculated with a random-effects model. Six prospective cohort studies with 5827 lung cancer cases among 831,535 participants were included in our meta-analysis. Each 10 cm increase in WC and 0.1 unit increase in WHR were associated with 10% (RR 1.10; 95% CI 1.04, 1.17; I2 = 27.7%, p-heterogeneity = 0.198) and 5% (RR 1.05; 95% CI 1.00, 1.11; I2 = 25.2%, p-heterogeneity = 0.211) greater risks of lung cancer, respectively. According to smoking status, greater WHR was only positively associated with lung cancer among former smokers (RR 1.11; 95% CI 1.00, 1.23). In contrast, greater WC was associated with increased lung cancer risk among never smokers (RR 1.11; 95% CI 1.00, 1.23), former smokers (RR 1.12; 95% CI 1.03, 1.22) and current smokers (RR 1.16; 95% CI 1.08, 1.25). The summary RRs for highest versus lowest categories of WC and WHR were 1.32 (95% CI 1.13, 1.54; I2 = 18.2%, p-heterogeneity = 0.281) and 1.10 (95% CI 1.00, 1.23; I2 = 24.2%, p-heterogeneity = 0.211), respectively. In summary, abdominal obesity may play an important role in the development of lung cancer.

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To systematically and quantitatively review the relation of abdominal obesity, as measured by waist circumference (WC) and waist to hip ratio (WHR), to total gastroesophageal cancer, gastric cancer (GC), and esophageal cancer. PubMed and Web of Science databases were searched for studies assessing the association between abdominal obesity and gastroesophageal cancer (GC and/or esophageal cancer) up to August 2016. A random-effect model was used to calculate the summary relative risks (RRs) and 95% confidence intervals (CIs). Seven prospective cohort studies – one publication included two separate cohorts – from six publications were included in the final analysis. A total of 2130 gastroesophageal cancer cases diagnosed amongst 913182 participants. Higher WC and WHR were significantly associated with increased risk of total gastroesophageal cancer (WC: RR 1.68, 95% CI: 1.38, 2.04; WHR: RR 1.49, 95% CI: 1.19, 1.88), GC (WC: RR 1.48, 95% CI: 1.24, 1.78; WHR: 1.33, 95% CI: 1.04, 1.70), and esophageal cancer (WC: RR 2.06, 95% CI: 1.30, 3.24; WHR: RR 1.99, 95% CI: 1.05, 3.75).Findings from our subgroup analyses showed non-significant positive associations between gastric non-cardia adenocarcinoma (GNCA) and both measures of abdominal adiposity, while gastric cardia adenocarcinoma (GCA) was positively associated with WC but not with WHR. On analysis restricted to studies that adjusted for body mass index (BMI), WC was positively associated with GC and esophageal cancer, whereas WHR was positively associated with risk of GC only. Although limited, the findings from our meta-analysis suggest the potential role of abdominal obesity in the etiology of gastric and esophageal cancers.

Certain glucose-lowering medications have been implicated in the risk of fracture.While there is convincing evidence from randomized controlled trials (RCTs) that thiazolidinedione use is associated with a higher risk of fracture, the effects of metformin, insulin, and sulphonylureas on the risk of fracture remain equivocal because these medications are not generally investigated in RCTs. A meta-analysis of observational studies to provide further insights into the association between the use of metformin, insulin, sulphonylureas, or thiazolidinediones and the risk of fracture was performed. PubMed and Web of Science databases were searched to identify relevant observational studies. A random effects model was used to estimate the summary relative risks (RRs) with 95% confidence intervals (CIs). The use of insulin (RR 1.49, 95% CI 1.29, 1.73; n = 23 studies), sulphonylureas (RR 1.30, 95% CI 1.18, 1.43; n = 10), and thiazolidinediones (RR 1.24, 95% CI 1.13, 1.35; n = 14) was associated with an increased risk of fracture, whereas the use of metformin was associated with a reduced risk of fracture (RR 0.86, 95% CI 0.75, 0.99; n = 12). Regarding types of thiazolidinediones, both pioglitazone (RR 1.38, 95% CI 1.23, 1.54; n = 5) and rosiglitazone (RR 1.34, 95% CI 1.14, 1.58; n = 5) were positively associated with the risk of fracture. In summary, there is compelling evidence to discourage the use of thiazolidinediones in individuals with an increased risk of fracture, whereas metformin appears to have a good safety profile for the risk of fracture. The reduced risk of fracture with metformin could possibly be due to the reduced overall risk of fracture among metformin users, as this medication is typically prescribed in the early stages of type 2 diabetes mellitus. The use of insulin or sulphonylureas may increase fracture risk; this risk is most likely attributed to an increased risk of hypoglycaemia-induced falls. Further confirmation by additional RCTs is required to determine whether the observed association between the use of metformin, insulin, or sulphonylureas and the risk of fracture is due to treatment with these medications or confounding factors.

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PurposeTo report calculated crystalline lens power and describe the distribution of ocular biometry and its association with refractive error in older Chinese adults.MethodsRandom clustering sampling was used to identify adults aged 50 years and above in Xuhui and Baoshan districts of Shanghai. Refraction was determined by subjective refraction that achieved the best corrected vision based on monocular measurement. Ocular biometry was measured by IOL Master. The crystalline lens power of right eyes was calculated using modified Bennett-Rabbetts formula.ResultsWe analyzed 6099 normal phakic right eyes. The mean crystalline lens power was 20.34 ± 2.24D (range: 13.40–36.08). Lens power, spherical equivalent, and anterior chamber depth changed linearly with age; however, axial length, corneal power and AL/CR ratio did not vary with age. The overall prevalence of hyperopia, myopia, and high myopia was 48.48% (95% CI: 47.23%–49.74%), 22.82% (95% CI: 21.77%–23.88%), and 4.57% (95% CI: 4.05–5.10), respectively. The prevalence of hyperopia increased linearly with age while lens power decreased with age. In multivariate models, refractive error was strongly correlated with axial length, lens power, corneal power, and anterior chamber depth; refractive error was slightly correlated with best corrected visual acuity, age and sex.ConclusionLens power, hyperopia, and spherical equivalent changed linearly with age; Moreover, the continuous loss of lens power produced hyperopic shifts in refraction in subjects aged more than 50 years.