Other Confounders (other + confounder)

Distribution by Scientific Domains


Selected Abstracts


Brachial-ankle pulse wave velocity and cardiovascular risk factors in the non-diabetic and newly diagnosed diabetic Chinese: Guangzhou Biobank Cohort Study-CVD

DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 2 2010
Lin Xu
Abstract Background Increased arterial stiffness is an important cause of cardiovascular disease (CVD). We examined determinants of arterial stiffness in subjects across strata of glycaemic status. Methods A total of 1249 subjects from a sub-study of the Guangzhou Biobank Cohort Study (GBCS-CVD) had brachial-ankle pulse wave velocity (baPWV) measured by automatic oscillometric method. Major cardiovascular risk factors including glycosylated haemoglobin A1c (HbA1c), high sensitivity C-reactive protein (hsCRP), fasting triglyceride, low- and high-density lipoprotein cholesterol and both fasting and post 2-h oral glucose-load glucose, systolic and diastolic blood pressure were assessed. Results In all, 649, 479 and 121 subjects were classified into normoglycaemia, impaired glucose metabolism (IGM) and newly diagnosed diabetes groups, respectively. Both age and systolic blood pressure were significantly associated with increased baPWV in all three groups (all p < 0.001). In both normoglycaemic and IGM groups, hsCRP and HbA1c were positively associated with baPWV (p from 0.04 to < 0.001), whereas current smoking and triglyceride were associated with baPWV in the normoglycaemic and IGM group, respectively (p = 0.04 and 0.001). No gender difference in baPWV was observed in the normoglycaemic or IGM groups. However, in the newly diagnosed diabetes group, men had higher baPWV than women (p = 0.01). Conclusions In the normoglycaemic and IGM subjects, after adjusting for age, blood pressure and other confounders, increasing HbA1c was associated with increased baPWV, suggesting a pathophysiological role of chronic glycaemia that can contribute to vascular disease risk in persons without diabetes. Copyright © 2010 John Wiley & Sons, Ltd. [source]


Prediagnostic levels of C-peptide, IGF-I, IGFBP -1, -2 and -3 and risk of endometrial cancer,

INTERNATIONAL JOURNAL OF CANCER, Issue 2 2004
Annekatrin Lukanova
Abstract Conditions related to chronic hyperinsulinemia, such as obesity, noninsulin dependent diabetes mellitus and polycystic ovary syndrome, are associated with an increased risk of endometrial cancer. Elevated plasma IGF-I and decreased levels of IGF-binding proteins have been shown to be associated with increased risk of several cancer types that are frequent in affluent societies. We investigated for the first time in a prospective study the association of pre-diagnostic blood concentrations of C-peptide (a marker of pancreatic insulin production), IGF-I, IGFBP-1, -2 and -3 with endometrial cancer risk. A case-control study was nested within 3 cohorts in New York (USA), Umeå (Sweden) and Milan (Italy). It included 166 women with primary invasive endometrial cancer and 315 matched controls, of which 44 case and 78 control subjects were premenopausal at recruitment. Endometrial cancer risk increased with increasing levels of C-peptide (ptrend = 0.0002), up to an odds ratio (OR) of 4.76 [95% confidence interval (CI) = 1.91,11.8] for the highest quintile. This association remained after adjustment for BMI and other confounders [OR for the top quintile = 4.40 (1.65,11.7)]. IGFBP-1 levels were inversely related to endometrial cancer [ptrend = 0.002; OR in the upper quintile = 0.30 (0.15,0.62)], but the association was weakened and lost statistical significance after adjustment for confounders [ptrend = 0.06; OR in the upper quintile = 0.49 (0.22,1.07)]. Risk was unrelated to levels of IGF-I, IGFBP-2 and IGFBP-3. Chronic hyperinsulinemia, as reflected by increased circulating C-peptide, is associated with increased endometrial cancer risk. Decrease in the prevalence of chronic hyperinsulinemia, through changes in lifestyle or medication, is expected to prevent endometrial cancer. © 2003 Wiley-Liss, Inc. [source]


Lung function, insulin resistance and incidence of cardiovascular disease: a longitudinal cohort study

JOURNAL OF INTERNAL MEDICINE, Issue 5 2003
G. Engström
Abstract., Engström G, Hedblad B, Nilsson P, Wollmer P, Berglund G, Janzon L (University of Lund, Malmö University Hospital, Malmö, Sweden). Lung function, insulin resistance and incidence of cardiovascular disease: a longitudinal cohort study. J Intern Med 2003; 253: 574,581. Objectives., To explore whether a reduced lung function is a risk factor for developing diabetes and insulin resistance (IR), and whether such relationship contributes to the largely unexplained association between lung function and incidence of cardiovascular disease (CVD). Design., Forced vital capacity (FVC) was assessed at baseline. Incidence of diabetes and IR [according to the homeostasis model assessment (HOMA) model] was assessed in a follow-up examination after 13.9 ± 2.6 and 9.4 ± 3.6 years for men and women, respectively. After the follow-up examination, incidence of CVD (stroke, myocardial infarction or cardiovascular death) was monitored over 7 years. Setting., Populations-based cohort study. Subjects., Initially nondiabetic men (n = 1436, mean age 44.6 years) and women (n = 896, mean age 49.8 years). Results., Prevalence of IR at the follow-up examination was 34, 26, 21 and 21%, respectively, for men in the first (lowest), second, third and fourth quartile of baseline FVC (P for trend <0.0001). The corresponding values for women were 30, 29, 25 and 17%, respectively (P for trend <0.001). Adjusted for potential confounders, the odds ratio (OR) for IR (per 10% increase in FVC) was 0.91 (CI: 0.84,0.99) for men and 0.89 (CI: 0.80,0.98) for women. FVC was similarly significantly associated with the incidence of diabetes (OR = 0.90, CI: 0.81,1.00), adjusted for sex and other confounders. The incidence of CVD after the follow-up examination was significantly increased only amongst subjects with low FVC who had developed IR (RR = 1.7, CI: 1.02,2.7). Conclusion., Subjects with a moderately reduced FVC have an increased risk of developing IR and diabetes. This relationship seems to contribute to the largely unexplained association between reduced lung function and incidence of CVD. [source]


Influence of glutathione- S -transferase theta (GSTT1) and mu (GSTM1) gene polymorphisms on the susceptibility of hepatocellular carcinoma in Taiwan,

JOURNAL OF SURGICAL ONCOLOGY, Issue 4 2010
Chia-Chun Kao MD
Abstract Background and Objectives Hepatocellular carcinoma (HCC) is one of the most frequent malignant neoplasms worldwide and is the second leading cause of cancer death in Taiwan. Genetic polymorphism has been reported as a factor for increased susceptibility of HCC. Glutathione- S -transferases theta (GSTT1) and mu (GSTM1) play essential roles in detoxification of ingested xenobiotics and modulation of the susceptibility of gene-related cancer. The aim of this study was to estimate the relationships between these two gene polymorphisms and HCC risk and clinicopathological status in Taiwanese. Methods Polymerase chain reaction (PCR) was used to determine gene polymorphisms of 102 patients with HCC and 386 healthy controls. Results Both gene polymorphisms were not associated with the clinical pathological status of HCC and serum levels of liver-related clinical pathological markers. While no relationship between GSTM1 gene polymorphism and HCC susceptibility was found, individuals of age <56 years old with GSTT1 present genotype have a risk of 2.77-fold (95% CI: 1.09,7.09) for HCC compared to that with null variant, after adjustment for other confounders. Conclusions GSTT1 and GSTM1 null genotypes do not associate with increased risk of HCC. J. Surg. Oncol. 2010;102:301,307. © 2010 Wiley-Liss, Inc. [source]


Hypoxia inducible factor-1, gene polymorphism G1790A and its interaction with tobacco and alcohol consumptions increase susceptibility to hepatocellular carcinoma,

JOURNAL OF SURGICAL ONCOLOGY, Issue 2 2010
Pei-Ching Hsiao MD
Abstract Background and Objectives The aim of this study was to examine the potential associations of two hypoxia inducible factor-1, (HIF-1,) gene polymorphisms, C1772T and G1790A, with the susceptibility and clinicopathological status of hepatocellular carcinoma. Methods A total of 449 subjects, including 347 healthy controls and 102 patients with hepatocellular carcinoma, were recruited in this study and subjected to polymerase chain reaction,restriction fragment length polymorphism (PCR-RFLP) analyses to estimate the impact of these two polymorphic variants on hepatocellular carcinoma. Results G1790A heterozygotes showed a higher risk for hepatocellular carcinoma, compared with GG genotypes after adjusting for other confounders (AOR,=,3.97; 95%CI,=,1.70,9.22), indicating a significant association between hepatocellular carcinoma susceptibility and G1790A polymorphism. Moreover, results also revealed the presence of synergistic effect between gene polymorphism of HIF-1, G1790A and environmental risk factors, such as tobacco and alcohol consumptions while there was no significant association between HIF-1, gene polymorphism and clinicopathological parameters of hepatocellular carcinoma. Conclusions Genetic polymorphism at G1790A of HIF-1, is an important factor for determining the susceptibility to hepatocellular carcinoma. The interaction effects of G1790A heterozygotes to tobacco and to alcohol consumption significantly increase the risk to develop hepatocellular carcinoma. J. Surg. Oncol. 2010;102:163,169. © 2010 Wiley-Liss, Inc. [source]


Second trimester amniotic fluid annexin A5 levels and subsequent development of intrauterine growth restriction

PRENATAL DIAGNOSIS, Issue 10 2008
Ozgur Dundar
Abstract Objective The purpose of this study was to investigate the levels of annexin A5 in second trimester amniotic fluid, and evaluate its correlation with subsequent development of intrauterine growth restriction (IUGR). Method A total of 264 women undergoing mid-trimester amniocentesis between January 2007 and December 2007 were enrolled for the study. Amniocentesis was performed for routine indications. After delivery, outcome data were obtained. Results Maternal age, frequency of nulliparity, fetal sex and gestational week at amniocentesis were similar between groups. As expected, prevalence of smoking was higher in IUGR developing mothers. Significant positive correlations were present between annexin A5 levels and gestational age at amniocentesis (P = 0.02) and maternal age (P = 0.01). Linear regression analysis revealed that annexin A5 levels were positively correlated with patient's age. Smoking women had significantly lower annexin A5 levels in the mid-trimester amniotic fluid (9.9 ± 2.3 and 10.7 ± 1.3 ng/mL, P = 0.01). Logistic regression analysis demonstrated that after controlling for gestational age at amniocentesis, smoking, maternal age, and maternal hypertension, annexin A5 was not significantly associated with IUGR (P = 0.07). Conclusion Amniotic fluid annexin A5 levels in the mid-trimester are not associated with IUGR at birth after controlling for maternal smoking and other confounders. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Robust Quantitative Trait Association Tests in the Parent-Offspring Triad Design: Conditional Likelihood-Based Approaches

ANNALS OF HUMAN GENETICS, Issue 2 2009
J.-Y. Wang
Summary Association studies, based on either population data or familial data, have been widely applied to mapping of genes underlying complex diseases. In family-based association studies, using case-parent triad families, the popularly used transmission/disequilibrium test (TDT) was proposed for avoidance of spurious association results caused by other confounders such as population stratification. Originally, the TDT was developed for analysis of binary disease data. Extending it to allow for quantitative trait analysis of complex diseases and for robust analysis of binary diseases against the uncertainty of mode of inheritance has been thoroughly discussed. Nevertheless, studies on robust analysis of quantitative traits for complex diseases received relatively less attention. In this paper, we use parent-offspring triad families to demonstrate the feasibility of establishment of the robust candidate-gene association tests for quantitative traits. We first introduce the score statistics from the conditional likelihoods based on parent-offspring triad data under various genetic models. By applying two existing robust procedures we then construct the robust association tests for analysis of quantitative traits. Simulations are conducted to evaluate empirical type I error rates and powers of the proposed robust tests. The results show that these robust association tests do exhibit robustness against the effect of misspecification of the underlying genetic model on testing powers. [source]


Corticosteroid phobia and other confounders in the treatment of childhood atopic dermatitis explored using parent focus groups

AUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 3 2010
Saxon D Smith
ABSTRACT Background/Objectives:, Anxieties associated with corticosteroid treatment and preference for ,safer natural therapy' are common in parents of children with atopic dermatitis. We used focus groups to explore the source of these attitudes. Methods:, The study involved 16 parents. Parents expressed difficulties with living with and treating atopic dermatitis which were categorized into themes using qualitative data analysis software. Results:, Themes identified include: emotional impact of atopic dermatitis; difficulty in accepting ,control' verses ,cure'; topical corticosteroid negative perceptions; anxiety and confusion with treatment; preference for ,natural' therapy; and attitude-changing positive experiences. Conclusions:, Our findings illustrate the emotional impact of atopic dermatitis and the frustration with the lack of potential cure. ,Corticosteroid phobia' was universal among parents in our cohort and is a fear generated by doctors, pharmacists, close acquaintances and information from the internet. Participants expressed high levels of parental guilt linked to a desire for an eradicable ,cause' for atopic dermatitis, despite intellectually understanding this is a genetically determined condition. Parents were willing to change attitudes with accurate information from perceived reliable sources, positive hospitalization experiences and a relationship with a trusted dermatologist. Parents' suggestions to improve confidence included the provision of readily available information and better access to doctor- and nurse-led paediatric dermatology services. [source]


Lens opacity and refractive influences on the measurement of retinal vascular fractal dimension

ACTA OPHTHALMOLOGICA, Issue 6 2010
Haitao Li
Acta Ophthalmol. 2010: 88: e234,e240 Abstract. Purpose:, To examine the influence of lens opacity and refraction on the measurement of retinal vascular fractal dimension (Df). Methods:, Optic disc photographs (right eyes) of 3654 baseline Blue Mountains Eye Study participants (aged 49,97 ) were digitized. Retinal vascular Df was quantified using a computer-based program. Summated severity scores for nuclear, cortical and posterior subcapsular (PSC) cataract were assessed from lens photographs. Refraction data were converted to spherical equivalent refraction (SER), as sum spherical plus 0.5 cylinder power. Axial length was measured at 10-year follow-up examinations using an IOL master. Results:, Mean Df of the retinal vasculature was 1.444 ± 0.023 for 2859 eligible participants. Increasing lens opacity scores were associated with significant reduction in Df (, = ,0.0030, p < 0.0001). Both cortical and PSC cataract involving central lens area were associated with reduced Df, after controlling for confounding factors (ptrend , 0.0105). Increasing myopia severity was associated with reduced Df after adjusting for lens opacity scores and other confounders (ptrend < 0.0001). The slope of Df decrease per SER reduction was 0.0040 in eyes with SER , ,4D, compared to ,0.0016 in eyes with SER > ,4D. For axial length quintiles, there were no significant differences in mean Df in all groups except a reduction in the fifth quintile (axial length ,24.15 mm) (all p < 0.05). Conclusion:, Ocular media opacity independently influenced retinal vascular Df measurement, but we found no evidence supporting any refractive axial magnification effect on this measure. Myopic refraction ,,4D was associated with a reduction in Df, suggesting rarefaction of retinal vasculature associated with high myopia. [source]