Epidemiology Study (epidemiology + study)

Distribution by Scientific Domains


Selected Abstracts


Lack of association between serum adiponectin levels and the Pro12Ala polymorphism in Asian Indians

DIABETIC MEDICINE, Issue 4 2007
V. Radha
Abstract Aims, The aim of the study was to investigate the association of serum adiponectin levels with the Pro12Ala polymorphism of the peroxisome proliferator activated receptor-, (PPARG) gene in Asian Indians. Methods, We selected 400 diabetic subjects, 200 with the Pro12Pro genotype (100 male and 100 female) and 200 with the Pro12Ala genotype (100 male and 100 female) and 400 age- and sex-matched normal glucose tolerance subjects with similar genotype profiles from the Chennai Urban Rural Epidemiology Study. Fasting serum adiponection levels were measured using radioimmunoassay. The Pro12Ala polymorphism was genotyped by PCR,restriction fragment length polymorphism using BstUI. Results, All clinical and biochemical parameters were similar in the subjects with the Pro12Pro and Pro12Ala genotypes. There was no significant difference in serum adiponectin values between subjects with the Pro12Pro and Pro12Ala genotypes (males 5.4 vs. 5.8 µg/ml, P = 0.546; females 6.9 vs. 7.2 µg/ml, P = 0.748). Adiponectin values did not differ among these two genotypes even when categorized based on their diabetes status (normal glucose tolerance Pro12Pro 7.9 vs. Pro12Ala 7.7 µg/ml, P = 0.994; diabetes Pro12Pro 4.7 vs. Pro12Ala 5.4 µg/ml, P = 0.622). Conclusion, The Pro12Ala polymorphism of the PPARG gene is not associated with serum adiponectin levels in Asian Indians. [source]


Peroxisome proliferator-activated receptor-, co-activator-1, (PGC-1,) gene polymorphisms and their relationship to Type 2 diabetes in Asian Indians

DIABETIC MEDICINE, Issue 11 2005
K. S. Vimaleswaran
Abstract Aims The objective of the present investigation was to examine the relationship of three polymorphisms, Thr394Thr, Gly482Ser and +A2962G, of the peroxisome proliferator activated receptor-, co-activator-1 alpha (PGC-1,) gene with Type 2 diabetes in Asian Indians. Methods The study group comprised 515 Type 2 diabetic and 882 normal glucose tolerant subjects chosen from the Chennai Urban Rural Epidemiology Study, an ongoing population-based study in southern India. The three polymorphisms were genotyped using polymerase chain reaction,restriction fragment length polymorphism (PCR,RFLP). Haplotype frequencies were estimated using an expectation,maximization (EM) algorithm. Linkage disequilibrium was estimated from the estimates of haplotypic frequencies. Results The three polymorphisms studied were not in linkage disequilibrium. With respect to the Thr394Thr polymorphism, 20% of the Type 2 diabetic patients (103/515) had the GA genotype compared with 12% of the normal glucose tolerance (NGT) subjects (108/882) (P = 0.0004). The frequency of the A allele was also higher in Type 2 diabetic subjects (0.11) compared with NGT subjects (0.07) (P = 0.002). Regression analysis revealed the odds ratio for Type 2 diabetes for the susceptible genotype (XA) to be 1.683 (95% confidence intervals: 1.264,2.241, P = 0.0004). Age adjusted glycated haemoglobin (P = 0.003), serum cholesterol (P = 0.001) and low-density lipoprotein (LDL) cholesterol (P = 0.001) levels and systolic blood pressure (P = 0.001) were higher in the NGT subjects with the XA genotype compared with GG genotype. There were no differences in genotype or allelic distribution between the Type 2 diabetic and NGT subjects with respect to the Gly482Ser and +A2962G polymorphisms. Conclusions The A allele of Thr394Thr (G , A) polymorphism of the PGC-1 gene is associated with Type 2 diabetes in Asian Indian subjects and the XA genotype confers 1.6 times higher risk for Type 2 diabetes compared with the GG genotype in this population. [source]


Data management and quality assurance for an International project: the Indo,US Cross-National Dementia Epidemiology Study

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 6 2002
Rajesh Pandav
Abstract Background Data management and quality assurance play a vital but often neglected role in ensuring high quality research, particularly in collaborative and international studies. Objective A data management and quality assurance program was set up for a cross-national epidemiological study of Alzheimer's disease, with centers in India and the United States. Methods The study involved (a) the development of instruments for the assessment of elderly illiterate Hindi-speaking individuals; and (b) the use of those instruments to carry out an epidemiological study in a population-based cohort of over 5000 persons. Responsibility for data management and quality assurance was shared between the two sites. A cooperative system was instituted for forms and edit development, data entry, checking, transmission, and further checking to ensure that quality data were available for timely analysis. A quality control software program (CHECKS) was written expressly for this project to ensure the highest possible level of data integrity. Conclusions This report addresses issues particularly relevant to data management and quality assurance at developing country sites, and to collaborations between sites in developed and developing countries. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Bone Loss, Weight Loss, and Weight Fluctuation Predict Mortality Risk in Elderly Men and Women

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2007
Nguyen D Nguyen
Abstract Low baseline BMD, rate of BMD loss, weight loss, and weight fluctuation are significant predictors of all-cause mortality in elderly men and women, independent of each other and of age, incident fracture, and concomitant diseases. Introduction: Although low BMD has been shown to be associated with mortality in women, the effect of BMD is affected by weight and weight change and the contribution of these factors to mortality risk, particularly in men, is not known. This study examined the association between baseline BMD, rate of bone loss, weight loss, and weight fluctuation and all-cause mortality risk in elderly men and women. Materials and Methods: Data from 1059 women and 644 men, ,60 years of age (as of 1989), of white background who participated in the Dubbo Osteoporosis Epidemiology Study were analyzed. All-cause mortality was recorded annually between 1989 and 2004. BMD at the femoral neck was measured by DXA (GE-LUNAR) at baseline and at approximately every 2 yr afterward. Data on incident osteoporotic fractures and concomitant diseases, including cardiovascular diseases, all types of cancer, and type I/II diabetes mellitus, was also recorded. Results: In the multivariable Cox's proportional hazards model with adjustment for age, incident fractures, and concomitant diseases, the following variables were independent risk factors of all-cause mortality in men: rate of BMD loss of at least 1%/yr, rate of weight loss of at least 1%/yr, and weight fluctuation (defined by the CV) of at least 3%. In women, in addition to the significant factors observed in men, lower baseline BMD was also an independent risk factor of mortality. In both sexes, baseline weight was not an independent and significant predictor of mortality risk. Approximately 36% and 22% of deaths in women and men, respectively, were attributable to the four risk factors. Conclusions: These data suggest that, although low BMD was a risk factor of mortality in women, it was not a risk factor of mortality in men. However, high rates of BMD loss, weight loss, and weight fluctuation were also independent predictors of all-cause mortality in elderly men and women, independent of age, incident fracture, and concomitant diseases. [source]


Residual Lifetime Risk of Fractures in Women and Men,,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2007
Nguyen D Nguyen
Abstract In a sample of 1358 women and 858 men, ,60 yr of age who have been followed-up for up to 15 yr, it was estimated that the mortality-adjusted residual lifetime risk of fracture was 44% for women and 25% for men. Among those with BMD T-scores , ,2.5, the risks increased to 65% in women and 42% in men. Introduction: Risk assessment of osteoporotic fracture is shifting from relative risk to an absolute risk approach. Whereas BMD is a primary predictor of fracture risk, there has been no estimate of mortality-adjusted lifetime risk of fracture by BMD level. The aim of the study was to estimate the residual lifetime risk of fracture (RLRF) in elderly men and women. Materials and Methods: Data from 1358 women and 858 men ,60 yr of age as of 1989 of white background from the Dubbo Osteoporosis Epidemiology Study were analyzed. The participants have been followed for up to 15 yr. During the follow-up period, incidence of low-trauma, nonpathological fractures, confirmed by X-ray and personal interview, were recorded. Incidence of mortality was also recorded. BMD at the femoral neck was measured by DXA (GE-LUNAR) at baseline. Residual lifetime risk of fracture from the age of 60 was estimated by the survival analysis taking into account the competing risk of death. Results: After adjusting for competing risk of death, the RLRF for women and men from age 60 was 44% (95% CI, 40,48) and 25% (95% CI, 19,31), respectively. For individuals with osteoporosis (BMD T-scores , ,2.5), the mortality-adjusted lifetime risk of any fracture was 65% (95% CI, 58,73) for women and 42% (95% CI, 24,71) for men. For the entire cohort, the lifetime risk of hip fracture was 8.5% (95% CI, 6,11%) for women and 4% (95% CI, 1.3,5.4%) for men; risk of symptomatic vertebral fracture was 18% (95% CI, 15,21%) for women and 11% (95% CI, 7,14%) for men. Conclusions: These estimates provide a means to communicate the absolute risk of fracture to an individual patient and can help promote the identification and targeting of high-risk individuals for intervention. [source]


Incidence of Hip and Other Osteoporotic Fractures in Elderly Men and Women: Dubbo Osteoporosis Epidemiology Study,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2004
Kevin P Chang
Abstract In this prospective 12-year study in men and women 60 years of age and older, there was a 4,6% per year reduction in the incidence rate of overall osteoporotic fractures, but the study was unable to exclude any change in the hip fracture incidence rate. Approximately one-half of hip fractures occurred before 80 years in men and two-thirds before 85 years in women. The age distribution of hip fractures underlines the need for earlier intervention in osteoporosis. Introduction: Although hip fracture is the major osteoporotic fracture in terms of health outcomes, quality of life, and costs, there is a paucity of long-term data on secular changes in men and women within a defined community. This long-term prospective population-based study over 12 years from 1989 to 2000 specifically examined the age distribution and secular changes in the incidence rates of hip and other osteoporotic fractures in men and women 60 years of age and older in a predominantly white population in Dubbo, Australia. Materials and Methods: Hip and all other clinical fractures were ascertained by reviewing all radiography reports from the two area radiology services, ensuring complete ascertainment of all clinical osteoporotic fractures. Results and Conclusion: Among the 1055 symptomatic atraumatic fractures (after excluding pathological fractures), there was a significant reduction in the overall fracture incidence rate in women (4% per year; p = 0.0003) and men (6% per year; p = 0.0004) over the 12 years. There were 229 hip fractures (175 in women and 54 in men) within 39,357 person-years of observation. The overall rate ± SE of hip fracture was 759 ± 57 per 100,000 person-years in women and 329 ± 45 per 100,000 person-years in men, with an exponential increase with age. With advancing age, the incidence rate of hip fractures in men approached that in women; the female:male ratio fell from 4.5 (95% CI: 1.3,15.7) to 1.5 (0.9,2.5) and 1.9 (1.2,2.8) in the 60,69, 70,79, and 80+ year age groups, respectively. In women, the absolute number of fractures and incidence rate continuously increased with age; however, in men, the absolute number of hip fractures peaked at 80,84 years of age and then decreased. Most importantly, despite the continuing increase with age, almost one-half (48%) of the hip fractures occurred before the age of 80 years in men, and 66% of hip fractures occurred before the age of 85 years in women. The overall hip fracture incidence is comparable with other white (except Sweden) and Asian groups as well as two other Australian studies. This study could not exclude a change in hip fracture incidence rate, even in those 80 years of age and over among whom the incidence of hip fractures was the highest. The incidence data highlight the fact that a large proportion of hip fractures occurs in those under 80 years of age, particularly in men. This age distribution underlines the need for earlier intervention in osteoporosis in women and particularly in men to achieve the most cost-effective outcomes. [source]


Bleeding on probing differentially relates to bacterial profiles: the Oral Infections and Vascular Disease Epidemiology Study

JOURNAL OF CLINICAL PERIODONTOLOGY, Issue 6 2008
Ryan T. Demmer
Abstract Aim: Various bacterial species are differentially prevalent in periodontal health, gingivitis or periodontitis. We tested the independent associations between three bacterial groupings and gingival inflammation in an epidemiological study. Material and Methods: In 706 Oral Infections and Vascular Disease Epidemiology Study (INVEST) participants 55 years, bleeding on probing (BoP), pocket depth (PD) and subgingival plaque samples (n=4866) were assessed in eight sites per mouth. Eleven bacterial species were quantitatively assayed and grouped as follows: (i) aetiologic burden (EB, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia); (ii) putative burden (PB, Campylobacter rectus, Eikenella corrodens, Fusobacterium nucleatum, Micromonas micros, Prevotella intermedia); (iii) health-associated burden (HAB, Actinomyces naeslundii, Veillonella parvula). Results: After mutual adjustment for EB, PB and HAB, the BoP prevalence increased by 45% ( p<0.0001) across increasing quartiles of EB while BoP decreased by 13% ( p<0.0001) across increasing quartiles of HAB. Mean PD increased 0.8 mm and decreased 0.3 mm from the first to fourth quartiles of EB (p<0.0001) and HAB ( p<0.0001), respectively. Among 1214 plaque samples with fourth quartile EB, 60% were collected from sites with PD 3 mm. Conclusion: Bacterial species believed to be aetiologically related to periodontitis were associated with BoP in sites with minimal PD and/or attachment level (AL). Species presumed to be associated with periodontal health demonstrated inverse associations with BoP. [source]


Interactions between genetic and reproductive factors in breast cancer risk in a population-based sample of African-American families

GENETIC EPIDEMIOLOGY, Issue 4 2002
Valérie Chaudru
Abstract Incidence of breast cancer (BC) varies among ethnic groups, with higher rates in white than in African-American women. Until now, most epidemiological and genetic studies have been carried out in white women. To investigate whether interactions between genetic and reproductive risk factors may explain part of the ethnic disparity in BC incidence, a genetic epidemiology study was conducted, between 1989 and 1994, at the Howard University Cancer Center (Washington, DC), which led to the recruitment of 245 African-American families. Segregation analysis of BC was performed by use of the class D regressive logistic model that allows for censored data to account for a variable age of onset of disease, as implemented in the REGRESS program. Segregation analysis of BC was consistent with a putative dominant gene effect (P < 0.000001) and residual sister-dependence (P < 0.0001). This putative gene was found to interact significantly with age at menarche (P = 0.048), and an interaction with a history of spontaneous abortions was suggested (P = 0.08). A late age at menarche increased BC risk in gene carriers but had a protective effect in non-gene carriers. A history of spontaneous abortions had a protective effect in gene carriers and increased BC risk in non-gene carriers. Our findings agree partially with a similar analysis of French families showing a significant gene × parity interaction and a suggestive gene × age at menarche interaction. Investigating gene × risk factor interactions in different populations may have important implications for further biological investigations and for BC risk assessment. Genet. Epidemiol. 22:285,297, 2002. © 2002 Wiley-Liss, Inc. [source]


Adiponectin and type 2 diabetes in Samoan adults

AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2009
Julia R. Dibello
Objective: Previous studies have established an association between adiponectin and type 2 diabetes. It is unclear whether adiponectin will be useful among Samoan Islanders, characterized by markedly elevated levels of obesity, in differentiating those at risk of developing type 2 diabetes. Methods: Cross-sectional, genetic epidemiology study of obesity in American Samoa and Samoa 2002,2003 (n = 1,599). Logistic regression provided adjusted odds ratios and 95% confidence intervals for the association between adiponectin, diabetes, and prediabetes (impaired fasting glucose). Results: There is a significant decreasing trend in the odds of diabetes and prediabetes across increasing quintiles of adiponectin with an OR of 2.8 (95% CI: 1.6, 5.0) and 2.9 (95% CI: 1.5, 5.7), respectively, in the lowest relative to the highest quintile of adiponectin (P -for-trend = 0.004 and 0.001). Conclusions: Adiponectin is an important correlate, independent of other risk factors, of the pathogenesis of type 2 diabetes among Samoan islanders and may help distinguish those at higher risk of developing this disease. Am. J. Hum. Biol. 2009. © 2008 Wiley-Liss, Inc. [source]


Evaluation of aneuploidy and DNA damage in human spermatozoa: applications in field studies

ANDROLOGIA, Issue 4-5 2000
S. D. Perreault
With the goal of incorporating measures of sperm nuclear integrity in an epidemiology study, semen samples from young Czech men were analysed for sperm aneuploidy and sperm chromatin structure in addition to routine measures of sperm production and quality. The exposure in question was to high seasonal air pollution containing reactive polyaromatic hydrocarbons potentially capable of affecting spermatogenesis and damaging sperm DNA. The sperm aneuploidy assay uses fluorescence in situ hybridization to label selected sperm chromosomes; as applied in this study, the sex chromosomes (X,Y) and chromosome 8 were targeted. The sperm chromatin structure assay detects sperm nuclei with increased susceptibility to denaturation, a feature that is associated with DNA damage. Logistically, these assays were relatively easy to incorporate into the study design. The aneuploidy assay provided information suggesting that exposure to high levels of air pollution may increase the risk of sperm aneuploidy and that it is important to control for exposure to cigarette smoke and/or alcohol in such studies. The sperm chromatin structure assay provided valuable baseline information about Czech semen donors and data suggestive of an adverse effect of smoking and air pollution on spermatozoa that merits further investigation. [source]


The first documented case of Aspergillus cardiac surgical site infection in Sweden: an epidemiology study using arbitrarily primed PCR

APMIS, Issue 8 2009
ANNA BERGMAN
Bergman A, Lignell A, Melhus Ĺ. The first documented case of Aspergillus cardiac surgical site infection in Sweden: an epidemiology study using arbitrarily primed PCR. APMIS 2009; 117: 568,74. Here we report two rare cases of severe thoracic Aspergillus fumigatus infections after lung and heart surgery at the same thoracic intensive care unit at the same time. The main objective was to identify a possible source of transmission. With arbitrarily primed polymerase chain reaction a patient-to-patient transmission could rapidly be ruled out as the cause of the first documented case of aspergillosis after open-heart surgery in Sweden. Although no definitive source was identified, a genetically similar strain was found in a contaminated supply room. [source]