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Results for “Biomarker variability”

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PubMed1997

Early prediction of risk in patients with suspected unstable angina using serum troponin T.

BACKGROUND: One-third of patients with rest angina are reported to have detectable cardiac troponin T in the serum and may be at increased risk of serious cardiac events. AIM: To investigate whether a single early estimation of serum troponin T was an independent predictor of serious cardiovascular complications in patients with suspected unstable angina. METHODS: A prospective cohort study in which patients with suspected rest angina had a serum troponin T estimation 14 hours after symptom onset and were classified using discriminator levels of serum troponin T of 0.05 and 0.1 microgram/L as well as a number of other variables. All patients were followed for six months to document any cardiac complications and a stepwise logistic regression analysis was conducted to determine independent risk factors of complications. RESULTS: One hundred and sixty-four patients were evaluated. Using a discriminator level of 0.05 microgram/L 54 patients (33%) had detectable troponin T. The admission ECG was the only independent predictor of cardiac events in hospital--odds ratio 4.0 (95% CI 1.7-9.6). Detectable troponin T did not appear to be an independent predictor of serious complications. During the six-month follow-up period, detectable troponin T using a discriminator of 0.05 microgram/L was an independent predictor of serious complications--odds ratio 3.7 (95% CI 1.8-7.6). CONCLUSIONS: In patients with suspected rest angina, detectable serum troponin T > 0.05 microgram/L is an independent predictor of serious cardiac events during the six-month follow-up period although not during hospitalisation. Using a single, early serum troponin T estimation and other variables available at the time of admission, a high risk subgroup who may benefit from early investigation and revascularisation can be identified.

Aged↗

PubMed2003

Expression of T/NK-cell and plasma cell antigens in nonhematopoietic epithelioid neoplasms. An immunohistochemical study of 447 cases.

We studied the expression of CD2, CD3, CD4, CD5, CD7, CD8, CD56, and CD138 in 447 cases of common human neoplasms with epithelioid features. CD2, CD3, CD4, and CD8 antigens were detected in none of 447 cases of nonhematopoietic tumors. CD5 and CD7 antigens were expressed in 12.3% and 19.5% of cases of nonhematopoietic tumors, respectively. Their expression was found primarily in adenocarcinomas from the gastrointestinal tract, breast, and female reproductive organs. The high expression of CD5 and CD7 antigen in pancreatic ductal carcinoma and cholangiocarcinoma and high expression of CD7 in epithelioid sarcoma may have diagnostic value. One quarter of cases were positive for CD56. Overexpression of CD56 antigen was detected mainly in neuroendocrine tumors or adenocarcinomas with neuroendocrine differentiation. Its consistent overexpression in adrenal cortical and thyroid tumors may have diagnostic usefulness. Virtually all tumor types studied were CD138+ with a variable positivity rate. The negative staining of CD138 in malignant mesothelioma may be useful for separating mesothelioma from metastatic adenocarcinoma.

Antigens, CD↗

PubMed2000

Spontaneously occurring hepatocellular neoplasia in adolescent cynomolgus monkeys (Macaca fascicularis).

Spontaneous hepatic neoplasms were identified in two adolescent (<5 years of age) male cynomolgus monkeys (Macaca fascicularis). Monkey No. 1 had a solitary hepatocellular carcinoma (HCC). Monkey No. 2 had multiple discrete tumors consisting of several poorly circumscribed HCCs and a mixed hepatocholangiocellular carcinoma (MHC). Metastases were not evident in either monkey. Histochemical and immunohistochemical stains were used to assess phenotypic alterations in the tumors. Many or most neoplastic hepatocytes (NHs) of both monkeys stained positive for low-molecular-weight cytokeratin (LMWCK), cytokeratin (CK) 8, and CK 18. In monkey No. 1, small aggregates of NHs were positive for carcinoembryonic antigen (CEA), glutathione S-transferase-pi (GST), and alpha-fetoprotein (AFP), but NHs were uniformly negative for CK 7. NHs in monkey No. 2 were negative for CEA and AFP but were multifocally positive for GST and CK 7. Broad-spectrum cytokeratin (BSCK), high-molecular-weight cytokeratin (HMWCK), and CK 19 did not react with NHs of either animal. Neoplastic cells forming ductlike structures in the MHC of monkey No. 2 stained with LMWCK, CK 7, CK8, CK 18, BSCK, and GST but not with HMWCK or CK 19. Tumors in both monkeys had enhanced pericellular fibronectin staining. Nonneoplastic parenchyma of both monkeys contained multiple discrete foci of cellular alteration and scattered aggregates of hepatocytes with strong cytoplasmic staining for fibronectin. Staining patterns of these tumors demonstrate immunophenotypic heterogeneity of the neoplastic cells within individual tumors and variability among tumors. This information may serve as a useful reference for others encountering similar lesions in primates.

Animals↗

PubMed2006

Influence of gender on the prognostic value of troponin I after elective percutaneous coronary interventions.

OBJECTIVE: To evaluate the association between troponin I concentrations (TnI) in patients submitted to elective percutaneous coronary interventions (PCI) and adverse coronary events (ACE) during a six month follow-up period. METHODS: One hundred and eleven patients who had been submitted to an elective PCI were consecutively selected during a one year timeframe. The patients had stable angina (SA), unstable angina (UA) or silent ischemia (SI) and were asymptomatic for at least 72 hours before the procedure. TnI concentrations were measured between 8 and 24 hours after the PCI. Each patient was contacted by telephone six months later and interviewed regarding ACE which were defined as death, myocardial infarction, new revascularization and recurrent ischemia. RESULTS: Twenty-four patients showed elevated concentrations of TnI (21.6%) after the PCI regardless of clinical characteristics or procedure complications. Those who presented elevated TnI concentrations had higher event rates: 66.7 vs. 42.5% (RR=1.57; CI 95%=1.08-2.28). This risk seems to be higher in the subgroups of females and patients with a previous diagnosis of unstable angina. Multivariate analysis confirmed that gender was the only effect modifying co-variable associated with ACE risk, which is higher for females with elevated TnI concentrations (OR=7.22; CI 95%=1.4 -36.9) and unaltered for males (OR=1.26; CI 95%=0.35-4.55). CONCLUSION: Elevated TnI concentrations were a common occurrence after PCI and is a factor related to the development of ACE in the mid term. However, when adjusted for other variables, this effect is only maintained in female patients.

Aged↗

PubMed1999

A phase I study of recombinant interferon-beta in patients with advanced malignant disease.

To evaluate the safety, toxicity, and maximum tolerated dose (MTD) of IFN beta-1a (Rebif, Serono Laboratories, Inc.) in patients with malignant diseases unresponsive to standard therapies and to assess the pharmacodynamics and pharmacokinetics associated with IFN beta-1a administration, an open-label, single-center phase I study was designed. Thirty-four patients were enrolled and treated with IFN beta-1a. All had measurable solid neoplasms or evaluable hematological malignancies. All patients received a single i.v. bolus dose of IFN-beta-1a on day 1, followed 7 days later by daily s.c. injections for 28 consecutive days. Successive groups of three patients received increasingly higher doses (in geometric progression from 1.5 million international units (MIU)/m2 to 24 MIU/m2) until dose-limiting toxicities were noted. Pharmacokinetic and biological studies, including measurement of the activity of 2',5'-oligoadenylate synthetase (2',5'-OAS) in peripheral blood mononuclear cells and serum levels of soluble Tac (CD 25) and beta-2 microglobulin, were performed on patients who agreed to participate. i.v. and s.c. doses of IFN beta-1a up to 24 MIU/m2 were administered. The most frequent adverse events (AEs) were constitutional symptoms. Grade III AEs during i.v. dosing included fever, elevation of bilirubin, and infection unrelated to therapy. No grade IV events were seen. AEs noted during continuous s.c. therapy included fever, liver transaminase increase, albuminuria, fatigue, nausea, myalgia, and rigors. Dose-limiting toxicities were encountered during s.c. dosing at the 24-MIU/m2 and 18-MIU/m2 dose levels and included gastrointestinal toxicity, elevations of aspartate aminotransferase and alanine aminotransferase, and albuminuria. The s.c. MTD was determined to be 12 MIU/m2, although there was great variability in the individual patient's ability to tolerate IFN beta-1a. 2',5'-OAS activity, thought to be indicative of IFN activity, increased within hours after i.v. and s.c. dosing, with the level remaining persistently elevated during the s.c. daily injections. The highest peak level was attained in the 6-MIU/m2 group. There was no evidence that the increase in 2',5'-OAS activity decayed with repetitive dosing, nor was there evidence of accumulation in this pharmacodynamic marker. Serum beta-2-microglobulin levels showed a modest time- and dose-dependent increase after s.c. administration of IFN beta-1a, with the largest increase seen at the 24-MIU/m2 dose level. There were no clear dose-dependent responses noted in soluble Tac serum levels. IFN beta-1a was well-tolerated when administered by a single i.v. bolus injection at doses up to and including 24 MIU/m2. Daily s.c. injections for at least 28 days were well-tolerated at doses up to and including 12 MIU/m2, with some patients tolerating doses twice as high as this. The MTD for the i.v. route could not be clearly determined according to the guidelines of the protocol. However, i.v. bolus doses up to 24 MIU/m2 were relatively well-tolerated. For the s.c. route, the MTD was determined to be 12 MIU/m2, but there was great interpatient variability, with some patients able to tolerate higher doses.

2',5'-Oligoadenylate Synthetase↗

PubMed2002

Long-term variability of bone turnover markers in patients with non-metastatic breast cancer.

Variability of bone marker measurements is a major problem in their clinical application. Most studies on marker variability have been performed in healthy subjects and over relatively short intervals of time. We prospectively evaluated the long-term variability of bone markers in 102 postmenopausal women diagnosed with primary breast cancer. During follow up (8-48, median 30 mo.), no patient developed bone metastases or other skeletal disease. Patients were seen every 3 months and exactly timed blood/urine specimens were obtained. All analyses were performed after study end by the same technician, using a single batch of reagents per analyte. The coefficient of variation was calculated as CV (%) = square root(sigma(CVi2)/n) (CVi = SD/mean x 100; n = n of CVi). The least significant change (LSC) was then LSC (%) = Z x CV x square root(2). Z = 1.96 for a 95% confidence interval (LSC-95). In a subset of n = 10 patients with no potential interference during follow-up, lowest CVs were recorded for serum (s) calcium (5%), sTAP (12%) and sBAP (14%). The LSC-95 for these markers were 14%, 33% and 39%, respectively. Highest CVs were seen with urine (56%) and serum (42%) CTX (LSC-95: 155%, 117% resp.). We conclude that in breast cancer patients without bone metastases, long-term variability varied greatly between markers. For certain markers, the LSC seems considerably higher than previously reported.

Adult↗

PubMed2004

Lysosomal storage disorders.

This study was conducted to assess the variability of clinical expression of Lysosomal storage disorders (LSDs) and the selection of specific enzyme investigation to reach the differential diagnosis. Initially 150 children in the age range of 15 days to 13 years were screened for common metabolic disorder and based on screening results, clinical signs and symptoms, 30 children(4 mo-12 yr) of these were selected for the leukocyte enzyme study. Of these 21 were confirmed to have LSDs. The most common disorder was GM2-gangliosidosis (47.61%, 10/21) followed by mucopolysaccharidosis (33.33%; 7/21). All showed variable phenotypic expression. Metachromatic leukodystrophy (MLD) was observed in 9.5% (2/21) of children with arylsulphatase A enzyme deficiency, while two children had shown pseudodeficiency of arylsulphatase A. One case each of galactosialidosis and GMI-gangliosidosis were observed. We conclude that children with developmental delay, seizures, dysmorphic features and organomegaly, with or without positive urinary screening for common metabolic disorders, need to be investigated further for LSDs. Variability of clinical expression is commonly observed in LSDs which require further confirmation by specific leukocyte enzyme study.

Adolescent↗

PubMed2005

Gene expression in kidney cancer is associated with cytogenetic abnormalities, metastasis formation, and patient survival.

Current diagnosis of renal cancer consists of histopathologic examination of tissue sections and classification into tumor stages and grades of malignancy. Until recently, molecular differences between tumor types were largely unknown. To examine such differences, we did gene expression measurements of 112 renal cell carcinoma and normal kidney samples on renal cell carcinoma-specific cDNA microarrays containing 4,207 genes and expressed sequence tags. The gene expression patterns showed deregulation of complete biological pathways in the tumors. Many of the molecular changes corresponded well to the histopathologic tumor types, and a set of 80 genes was sufficient to classify tumors with a very low error rate. Distinct gene expression signatures were associated with chromosomal abnormalities of tumor cells, metastasis formation, and patient survival. The data highlight the benefit of microarrays to detect novel tumor classes and to identify genes that are associated with patient variables and tumor properties.

Adult↗

PubMed1991

[Molecular epidemiological markers of Legionella pneumophila in the Valencian Community (I). Plasma levels].

We have investigated the presence of plasmids in 96 Legionella pneumophila serogroup 1 strains isolated from clinical and environmental samples from the Valencia area. Our results show a higher incidence of a 83 MD plasmid present in clinical as well as in environmental isolates, and a 120 MD plasmid with lower incidence and observed exclusively in strains isolated from one area. The variability in plasmid detection from L. pneumophila and the effect on it in a hospital after disinfection treatment is considered.

Biomarkers↗

PubMed1994

[Predictive value of certain clinical parameters in the myelodysplastic syndromes].

Myelodysplasic Syndromes (MDS) are a group of hematological entities whose feature is their evolution, in a variable percentage, to acute non-lymphoid leukemia (ANLL) with a very poor prognosis despite the new therapeutical advances. Our purpose was to study the predictive value of certain clinical parameters at the time of the diagnosis, in order to identify the patients with the worst prognosis and, thus, the ones in which the adoption of more aggressive therapeutical measures than a simple support therapy would be justified. This is why we conducted a predictive analysis of 22 hematological variables (13 quantitative and 9 qualitative in 41 patients diagnosed of MDS). Based on the results of such study, we conclude that the average survival of the patients with MDS ranges between 11 and 33 months, 17% evolving to ANLL. The predictive parameters of poor prognosis are younger ages, leukocytary count, neutrophil and platelet count, as well as the degree of medullary blastosis. The following variables did not have any predictive value: sec, multinuclearity, macroblastic maturity, karyorrhexis, increase of immature forms, hypoglanularity in the white series and megakaryocytic count.

Biomarkers↗

PubMed1993

Factors predicting outcome of rheumatoid arthritis: results of a followup study.

OBJECTIVE: To determine prognostic factors in rheumatoid arthritis (RA). METHODS: One hundred thirty-two women with definite RA were followed yearly from an early phase of the disease (symptoms < 5 years) for a mean duration of 6 years. The prognostic value of the first available clinical and laboratory variables and assessments of functional ability was related to several outcome measures (physician's opinion of disease severity, disease activity, radiological abnormalities, functional ability and number of prescribed 2nd-line drugs) by single predictor analysis and by logistic regression. RESULTS: The variables most predictive for one or more of the outcome measures were number of swollen joints, Ritchie score, health assessment questionnaire score, radiographical abnormalities, positive IgM rheumatoid factor (RF), positive IgG-RF, HLA-DR4, and an elevated percentage serum agalactosyl IgG. The accuracy of predicting outcome was calculated from several combinations of these variables, and varied between 70 and 80%. The accuracy based on a combination of the commonly available variables (number of swollen joints, IgM-RF and the erosion score), closely approximated the maximal accuracy that could be achieved. CONCLUSION: The outcome of RA can be predicted by a combination of variables that are commonly available in the clinical setting.

Adult↗

PubMed2026

Circulating Tumor DNA in Bladder Cancer: Current Clinical Evidence and Emerging Multi-Omics Perspectives-A Narrative Review.

Background: Circulating tumor DNA (ctDNA) analysis has emerged as a promising tool for real-time disease monitoring in muscle-invasive bladder cancer (MIBC). This narrative review summarizes current clinical evidence regarding ctDNA across disease stages. Methods: We examine recent translational and clinical findings, incorporating key prospective data from practice-changing trials, as well as insights into minimal residual disease (MRD) detection, treatment escalation and de-escalation strategies, and systemic barriers to adoption. Results: Postoperative ctDNA positivity consistently identifies patients with molecular residual disease (MRD) who face a substantially higher risk of recurrence and mortality, frequently preceding radiographic relapse by several months. Prospective evidence now validates ctDNA as a predictive biomarker to guide adjuvant immunotherapy escalation, while sustained ctDNA negativity correlates with high long-term disease-free survival. Beyond plasma ctDNA, emerging multi-compartment liquid biopsies-integrating urinary tumor DNA (utDNA)-demonstrate enhanced sensitivity, particularly in bladder-sparing and local surveillance settings. Furthermore, integrating genomic ctDNA profiling with novel post-transcriptional layers like epitranscriptomics offers a functional framework to capture tumor adaptation under therapeutic pressure. However, clinical translation remains constrained by a lack of assay harmonization, variable analytical sensitivity, and the need for standardized intervention thresholds. Conclusions: Longitudinal liquid biopsies are rapidly shifting MIBC management from static, stage-based paradigms toward dynamic, molecularly informed precision oncology. While ctDNA-guided strategies show robust clinical utility, prospective interventional validation and technical standardization are required before widespread routine integration.

biomarkers↗

PubMed1997

Density of the human crystalline lens is related to the macular pigment carotenoids, lutein and zeaxanthin.

PURPOSE: Although oxidative stress may play an important role in the development of age-related cataract, the degree of protection reported for antioxidant vitamins and carotenoids has been inconsistent across studies. These varied results may be due in part to the lack of good biomarkers for measuring the long-term nutritional status of the eye. The present experiments investigated the relationship between retinal carotenoids (i.e., macular pigment), used as a long-term measure of tissue carotenoids, and lens optical density, used as an indicator of lens health. METHODS: Macular pigment (460 nm) and lens (440, 500, and 550 nm) optical density were measured psychophysically in the same individuals. Groups of younger subjects--7 females (ages 24 to 36 years), and 5 males (ages 24 to 31 years)--were compared with older subjects--23 older females (ages 55 to 78 years), and 16 older males (ages 48 to 82 years). RESULTS: Lens density (440 nm) increased as a function of age (r = 0.65, p < 0.001), as expected. For the oldest group, a significant inverse relationship (y = 1.53-0.83x, r = -0.47, p < 0.001) was found between macular pigment density (440 nm) and lens density (440 nm). No relationship was found for the youngest group (p < 0.42). CONCLUSIONS: The main finding of this study was an age-dependent, inverse relationship between macular pigment density and lens density. Macular pigment is composed of lutein and zeaxanthin, the only two carotenoids that have been identified in the human lens. Thus, an inverse relationship between these two variables suggests that lutein and zeaxanthin, or other dietary factors with which they are correlated, may retard age-related increases in lens density.

Adult↗

PubMed2026

Enhanced risk stratification in hypertrophic cardiomyopathy through the integration of extracellular volume fraction on cardiovascular magnetic resonance.

AIMS: This study investigated the incremental prognostic value of cardiovascular magnetic resonance (CMR)-derived extracellular volume fraction (ECV), a marker of diffuse interstitial fibrosis, beyond late gadolinium enhancement (LGE) in hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: We analysed 990 consecutive HCM patients (median age 58 years, male 68.3%) who underwent CMR between 2012 and 2024. LGE and global ECV were quantified, and their associations with the primary endpoint of HCM-related events-a composite of sudden cardiac death (SCD) events, heart failure (HF) events, and HCM-related death-were assessed. During a median follow-up of 3.2 years, 64 (6.5%) patients experienced the primary endpoint. While LGE (median 7.1%, IQR 2.3-16.9%) and ECV (median 29.0%, IQR 26.6-32.0%) were moderately correlated (R = 0.604, P < 0.001), both were significantly associated with increased risk of the primary endpoint and individual outcomes of SCD and HF events, and optimal cutoffs were determined as LGE ≥ 27% and ECV ≥ 35%. Patients with ECV ≥ 35% had more symptoms, a more severe phenotype with greater systolic and diastolic dysfunction, and more pathogenic gene variants. Notably, ECV remained a significant predictor of the primary endpoint (adjusted HR 1.08, 95% CI 1.02-1.15, per 1%) after adjustment for key disease variables, including left ventricular ejection fraction and LGE. Elevated ECV effectively identified high-risk individuals even among lower-risk subgroups, including those with low LGE burden. CONCLUSION: Increased ECV is an independent predictor of HCM-related outcomes. ECV may serve as a novel imaging biomarker to refine risk stratification in HCM patients who do not meet traditional LGE-based high-risk criteria.

Humans↗

PubMed2006

Inflammation and dementia: epidemiologic evidence.

Based on experimental and neuropathologic studies, inflammation is postulated to play a central role in processes leading to neurodegeneration as well as vascular injury. To better understand the role of inflammation in cognitive disorders (CD), identify potential biomarkers for CD, and select individuals who may have a genetic susceptibility to CD, several different measures of inflammation have been employed in epidemiologic studies of CD, which are reviewed here. An inverse association of non-steroidal anti-inflammatory medications has been consistently reported. More variable are reports on the associations of various serum markers of cytokines to CD. There are few epidemiologic studies that have examined the association of CD and single nucleotide polymorphisms (SNP) regulating cytokines, although these have been examined in clinical case-control series. Data are summarized on the association of interleukin-1 SNPs from the Honolulu Asia Aging Study. There are many outstanding questions about the role of inflammation in CD and how best to measure it in the context of population-based studies.

Acute-Phase Proteins↗

PubMed2025

Advancing translational exposomics: bridging genome, exposome and personalized medicine.

Understanding the interplay between genetic predisposition and environmental and lifestyle exposures is essential for advancing precision medicine and public health. The exposome, defined as the sum of all environmental exposures an individual encounters throughout their lifetime, complements genomic data by elucidating how external and internal exposure factors influence health outcomes. This treatise highlights the emerging discipline of translational exposomics that integrates exposomics and genomics, offering a comprehensive approach to decipher the complex relationships between environmental and lifestyle exposures, genetic variability, and disease phenotypes. We highlight cutting-edge methodologies, including multi-omics technologies, exposome-wide association studies (EWAS), physiology-based biokinetic modeling, and advanced bioinformatics approaches. These tools enable precise characterization of both the external and the internal exposome, facilitating the identification of biomarkers, exposure-response relationships, and disease prediction and mechanisms. We also consider the importance of addressing socio-economic, demographic, and gender disparities in environmental health research. We emphasize how exposome data can contextualize genomic variation and enhance causal inference, especially in studies of vulnerable populations and complex diseases. By showcasing concrete examples and proposing integrative platforms for translational exposomics, this work underscores the critical need to bridge genomics and exposomics to enable precision prevention, risk stratification, and public health decision-making. This integrative approach offers a new paradigm for understanding health and disease beyond genetics alone.

Humans↗

PubMedDate not supplied

Polycyclic aromatic hydrocarbon-DNA adducts in white blood cells and urinary 1-hydroxypyrene in foundry workers.

In an ongoing comprehensive evaluation of biological markers, workers in or near an iron foundry with varying exposure to polycyclic aromatic hydrocarbons (PAH) were analyzed for molecular response to this exposure. Exposure to benzo(a)pyrene, determined by personal monitors worn by the workers (2 to 60 ng/m3), was considerably lower than in a previous study at this foundry (< 50 to 200 ng/m3) (F.P. Perera et al., Cancer Res., 48: 2288-2291, 1988). Two biomarkers, 1-hydroxypyrene in urine measured by high-performance liquid chromatography with fluorescence detection (a measure of internal dose) and PAH-DNA adducts in WBC measured by immunoassay (a measure of biologically effective dose) were assessed to demonstrate their relationship to the lowest exposures yet analyzed in foundry workers. In addition, these markers were analyzed for dose response and interindividual variability. Cigarette smoking, but not age or charbroiled food, influenced the level of 1-hydroxypyrene but not PAH-DNA adducts. When workers were classified into three exposure categories (low, medium, and high), mean 1-hydroxypyrene levels were 2.7, 1.8, and 3.6 mumol/mol creatinine, respectively. Comparisons by analysis of variance showed a significant difference between the groups after controlling for smoking (P = 0.02), but a trend test using multivariate linear regression analysis was not significant (r = 0.27; P = 0.07). Substantial interindividual variation was demonstrated by the 19- to 20-fold range in the values within each of the three exposure groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed2006

Associations between CB-153 and p,p'-DDE and hormone levels in serum in middle-aged and elderly men.

BACKGROUND: Animal and epidemiologic data indicate that exposure to persistent organochlorine pollutants (POPs) may disrupt the hypothalamus-pituitary-thyroid (HPT) and the hypothalamus-pituitary-gonadal (HPG) axes. We have assessed whether the POP-biomarkers 2,2'4,4',5,5'-hexachlorobiphenyl (CB-153) and 1,1-dichloro-2,2-bis(4-chlorophenyl)-ethene (p,p'-DDE) affect thyrotropin (TSH), thyroid hormones, gonadotropins or sex hormone concentrations in men. METHODS: Lipid adjusted serum concentrations of CB-153, and p,p'-DDE, were determined in 196 men (median age 59 years, range 48-82). Hormone analyses in serum were performed with immunoassays. The effect of CB-153 and p,p'-DDE (as continuous or categorized variables) were evaluated by linear regression models, adjusting for potential confounders. RESULTS: There was a significant positive association between p,p'-DDE and TSH. An increase of 100 ng/g lipid of p,p'-DDE corresponded to an increase of 0.03 mU/l (95% Confidence Interval (CI) 0.01, 0.05) in TSH level. The explanatory value (R(2)) of the multivariate model was only 7%. Moreover, there was a significant negative association between p,p'-DDE and estradiol. An increase of 100 ng/g lipid of p,p'-DDE corresponded to a decrease of 0.57 pmol/l (95% CI -1.0, -0.12) in estradiol level. The R(2)-value was only 4%. No associations were observed between any of the POP biomarkers and the other hormones. CONCLUSIONS: The positive association between p,p'-DDE and TSH and the negative association between p,p'-DDE and estradiol, among middle-aged and elderly men, were not accompanied by associations between the POP-markers and thyroxin, testosterone, and gonadotropins, respectively. The results gives some additional support for that POP exposure may affect HPT- and HPG-axes also in humans, but the overall epidemiological data are still not coherent enough to allow any firm conclusions.

Aged↗