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PubMedDate not supplied

Epidemiological study of tuberculosis in Palermo, Italy: IS6110 fingerprinting of Mycobacterium tuberculosis strains isolated in the years 1994-1998.

In some industrialized countries reemergence of tuberculosis has been recorded. Most cases are thought to be caused by reactivation of infections that had been acquired many years before, but in some geographical areas up to 40% of diagnosed infections have been estimated to be newly acquired, based on the results of molecular epidemiological methods. Restriction fragment length polymorphism of the insertion sequence IS6110 of Mycobacterium tuberculosis has been widely used to evaluate epidemiological patterns of transmission in various communities. We have used IS6110 fingerprinting to analyze 101 strains which were isolated between June 1994 and June 1998 from 95 inhabitants of the province of Palermo, Italy, an area with an endemic rate for tuberculosis ranging between 5.1 and 8.0 per 100,000 persons in the last 5 years. 89 different patterns have been obtained, 87.4% of the patients were infected by presumably unrelated isolates. Six microepidemics were also recognized. These data suggest that reactivation largely exceeds recent infection.

AIDS-Related Opportunistic Infections↗

PubMed2003

Interstitial cystitis, gynecologic pelvic pain, prostatitis, and their epidemiology.

AIM: To determine a uniform definition of interstitial cystitis (IC) and to develop a strategy on how to study its epidemiology. METHODS: Initially, the committee reviewed the literature regarding the definition of IC currently being used and information regarding its epidemiology. The committee held three 1-hour hearings and discussions on the opinions of invited IC specialists. The issues were presented and discussed. Consensus was sought when possible. The committee members met and summarized the gist of the three sessions. RESULTS: A consensus emerged as to what constitutes IC. Interstitial cystitis must have the elements of chronic pelvic pain and urinary frequency and/or urgency. It was also the recommendation that the term IC be retained followed by chronic pelvic pain syndrome represented by the acronym IC/CPPS. A strategy on the epidemiologic study of IC/CPPS was also recommended. CONCLUSIONS: A consensus from this workshop has emerged in terms of defining the component of IC, the preferred terminology, and the strategy to study its epidemiology.

Cystitis, Interstitial↗

PubMed2006

The USDA Automated Multiple-Pass Method accurately estimates group total energy and nutrient intake.

The imperative to address the national obesity epidemic has stimulated efforts to develop accurate dietary assessment methods suitable for large-scale applications. This study evaluated the performance of the USDA Automated Multiple-Pass Method (AMPM), the computerized dietary recall designed for the National Health and Nutrition Examination Survey dietary survey, and 2 epidemiological methods [the Block food-frequency questionnaire (Block) and National Cancer Institute's Diet History Questionnaire (DHQ)] using doubly labeled water (DLW) total energy expenditure (TEE) and 14-d estimated food record (FR) absolute nutrient intake as criterion measures. Twenty highly motivated, normal-weight-stable, premenopausal women participated in a free-living study that included 2 unannounced AMPM recalls and completion of the Block and DHQ. AMPM and FR total energy intake (TEI) did not differ significantly from DLW TEE [AMPM: 8982 +/- 2625 kJ; FR: 8416 +/- 2217; DLW: 8905 +/- 1881 (mean +/- SD)]. Conversely, the questionnaires underestimated TEI by approximately 28% (Block: 6365 +/- 2193; DHQ: 6215 +/- 1976; P < 0.0001 vs. DLW). Pearson correlation coefficients for DLW TEE with each dietary method TEI showed a stronger linear relation for AMPM (r = 0.53; P = 0.02) and FR (r = 0.41; P = 0.07) than for the Block (r = 0.25; P = 0.29) and DHQ (r = 0.15; P = 0.53). Most mean absolute FR nutrient intakes were closely approximated by the AMPM but were significantly underestimated by the questionnaires. In highly motivated premenopausal women, the AMPM provides valid measures of group total energy and nutrient intake whereas the Block and DHQ yield underestimations.

Adult↗

PubMed2001

Epidemiologic trends in the hospitalization of elderly Medicare patients for pneumonia, 1991-1998.

OBJECTIVES: This study determined hospitalization rates of elderly Americans for pneumonia from 1991 through 1998. METHODS: Epidemiologic data were described for 273,143 pneumonia hospitalizations. RESULTS: Annual hospitalizations for aspiration pneumonia increased by 93.5%. Pneumonia hospitalization rates increased steeply with age, especially among men. Black men were at highest risk for aspiration, unspecified, Klebsiella, "other gram-negative," and staphylococcal pneumonia; White men had the highest Haemophilus and pneumococcal pneumonia rates. Among women, Blacks predominated in aspiration and Klebsiella pneumonia; Whites had the highest Haemophilus and bronchopneumonia rates. CONCLUSIONS: An epidemic of hospitalization for aspiration pneumonia smoldered over 8 years. Significant disparities existed in hospitalization risks by race, sex, and principal diagnosis.

Black or African American↗

PubMed2004

[Study on the application of benchmark dose and biological monitoring indexes of fluorides in drinking water].

OBJECTIVE: By using Benchmark Dose (BMD) approach to explore the relations among drinking water fluoride, urine fluoride, serum fluoride and dental fluorosis; and to evaluate the significance of urine fluoride and serum fluoride in control and prevention of endemic fluorosis. METHODS: 512 children (290 in Xinhuai Village, 222 in Wamiao Village) aged 8-13 years were recruited in the study. Epidemiological methods were used to investigate the prevalence of dental fluorosis, and the levels of urine fluoride, serum fluoride, and drinking water fluoride in superficial well. The children were divided into six subgroups by the concentration of fluoride in drinking water: < 0.5 mg/L, 0.5-mg/L, 1.0-mg/L, 2.0-mg/L, 3.0-mg/L and > or = 4.0 mg/L. RESULTS: There was significant dose-response relationship between the drinking water fluoride and the prevalence of dental fluorosis or the prevalence of defect dental fluorosis. The BMDLs (Benchmark Dose Lower Bound) were 1.01 and 1.30 mg/L, respectively. Urine fluoride and serum fluoride also had significant dose-response relationship to the prevalence of dental fluorosis or defect dental fluorosis. The correlation coefficient between drinking water fluoride and urine fluoride was 0.717, and it was 0.855 between drinking water fluoride and serum fluoride, and 0.617 between urine fluoride and serum fluoride. CONCLUSIONS: The currently national standard of fluoride in drinking water in China is safe and reasonable. As a biological monitoring index, the levels of fluoride in serum may be more useful than that in urine in the control and prevention of endemic fluorosis.

Adolescent↗

PubMed2006

Phenon cluster analysis as a method to investigate epidemiological relatedness between sources of Campylobacter jejuni.

AIMS: To develop a method for assessing the relative epidemiological significance of possible infection sources for human campylobacteriosis. METHODS AND RESULTS: Using fluorescent amplified fragment length polymorphism (AFLP), 243 apparently epidemiologically unrelated Campylobacter jejuni isolates were genotyped (77 human, 46 cattle, 49 pet and 71 poultry isolates). In total 136 different phena were identified, of which 48 were clusters grouping at least two isolates. Isolates from different sources were frequently clustered together, underlining the high degree of source mixing and the lack of host specificity of C. jejuni. The phena were classified into different phenon types according to the sources of the isolates they contained. The occurrence of these phenon types was analysed using an area-proportional Euler diagram to describe epidemiological relatedness among C. jejuni isolates. Group separation statistics revealed that 43% of analysed human isolates expressed maximum similarity to other human isolates, 9% to cattle isolates, 21% to pet isolates and 27% to poultry isolates; these results were in accordance with the pattern observed in the phenon cluster analysis. CONCLUSIONS: Based on the grouping of strains into molecular similarity clusters, ecological patterns between sources can be investigated. SIGNIFICANCE AND IMPACT OF THE STUDY: This approach is a new methodological contribution to establish the relative epidemiological significance of concurrent infection sources.

Animals↗

PubMedDate not supplied

Epidemiology of neuroblastoma: analysis of a single institution.

BACKGROUND: Neuroblastoma is the fourth most frequent cancer among all pediatric neoplasms Epidemiological studies may shed more light on the disease and aid in improving treatment of patients with neuroblastoma. PATIENTS AND METHODS: Epidemiology data are presented for 333 children with neuroblastoma or ganglioneuroblastoma and 11 children with ganglioneuroma who were treated at the Institute of Mother and Child in Warsaw, Poland, from 1962 to 1996. RESULTS: Analysis of the stage of the disease, age, sex and survival of children with neuroblastoma demonstrated comparable distribution of good and intermediate stages versus the stages with a poor prognosis. CONCLUSION: Comprehensive analysis of epidemiological data on the stage of cancer, age, sex and survival in patients with neuroblastoma provides a basis for better prognosis of the disease and cost-efficient treatment.

Adolescent↗

PubMed1998

Diarrhea in returning Austrian tourists: epidemiology, etiology, and cost-analyses.

BACKGROUND: Between 1995 and 1997, stool samples of 322 Austrian tourists returning from abroad with diarrhea were examined for bacteria, parasites and viruses. METHODS: Epidemiologic data were collected from information furnished by physicians and hospitals and from questionnaires. Moreover, testing expenses and additional cost for treated cases were evaluated. RESULTS: In 97 of 322 patients examined (30%), one or more pathogens were detected in the stool. Bacteria were found in 38 patients (39%), parasites in 33 patients (34%) and viruses in 26 patients (27%). In 6 patients, mixed infections with parasites and viruses were detected and in 5 patients with bacteria and viruses. Among bacteria, Campylobacter jejuni was most frequent; among parasitic infections, Giardia lamblia. Significant correlations were established between the country of destination, age, travel style and length of stay. Forty-four percent of all patients visited Asia (including Turkey), 27% Africa, 18% Latin America, and only 10% southern Europe. The group between 20 and 29 years of age was most frequently affected (p<.001), the group between 0 and 19 years of age least. Fifty-seven percent stayed in a hotel without frequent changes of location; 43% undertook a trekking trip; and of those, 75% belonged to the group aged between 20 and 39. In terms of the correlation between travel style and pathogen, it was found that 74% of patients with bacterial infections stayed in a hotel (avg. 57.9%; p<.05) whereas 64% of all patients with parasitic infections undertook a trekking trip (avg. 42%; p<.001). Thirty-six percent of all patients with parasitic infections spent their vacation in India (avg. 13%; p<.001). The length of stay of patients with bacterial infections was shorter than average (72% spent between 1 and 2 weeks abroad, avg. 49.8%). Patients with parasitic infections spent significantly more time abroad than average (42% more than 2 months; avg. 17.7%; p<.001). Average cost of specific antimicrobial therapy was U.S.$31 whereas the average cost of identifying a patient needing such treatment was almost U.S.$580. CONCLUSION: Optimal detection rate and cost reduction for the diagnosis require precise history, adequate collection of samples using adequate transport media, and rapid transfer to the laboratory.

Adolescent↗

PubMed2004

Surveillance for retinopathy of prematurity in a Danish country. Epidemiological experience over 20 years.

PURPOSE: An updated analysis of the trends in a Danish county regarding retinopathy of prematurity (ROP), outlining its natural history over the years 1982-2001. METHODS: Epidemiological data are given of the 132 infants in the county with birth years 1998-2001 prospectively under surveillance for ROP. The customary national screening limits of gestational age (GA) and birthweight (BW) of 32 weeks/1750 g were generally adhered to. The findings are compared to five previous consecutive reports of a similar set-up, now making a total of 1123 who have been under surveillance. RESULTS: With focus on the 20 years' newborns at a higher risk for ROP in the county (GA/BW both under the above limits; n=591) the continuous improvement up to 1998--as reflected by ROP frequency, its severity, and risk levels according to GA/BW--appears to have been interrupted. Compared to the previous 4-year period, the percentage acquiring ROP in 1998-2001 increased from 10 to 31%, and four recent cases qualified for retinal ablation therapy, compared with zero in the previous 4-year period. However, there were no advanced stages (of at least ROP 3) in infants above 30 weeks/1500 g at delivery. CONCLUSIONS: (a) Using the ROP also as a neonatal treatment quality parameter, the present trend (progress stopped) should be followed attentively. So far, we have no clues regarding therapy-related or other causality. (b) Despite the suggested worsening, a lowering of the ophthalmic GA and BW screening limits now seems justifiable. With a view also to the high-risk Copenhagen data and the national childhood visual impairment register, a reduction of the values to 31 weeks/1500 g should be considered.

Birth Weight↗

PubMed2006

Analysis of cancer risk and BRCA1 and BRCA2 mutation prevalence in the kConFab familial breast cancer resource.

INTRODUCTION: The Kathleen Cuningham Foundation Consortium for Research into Familial Breast Cancer (kConFab) is a multidisciplinary, collaborative framework for the investigation of familial breast cancer. Based in Australia, the primary aim of kConFab is to facilitate high-quality research by amassing a large and comprehensive resource of epidemiological and clinical data with biospecimens from individuals at high risk of breast and/or ovarian cancer, and from their close relatives. METHODS: Epidemiological, family history and lifestyle data, as well as biospecimens, are collected from multiple-case breast cancer families ascertained through family cancer clinics in Australia and New Zealand. We used the Tyrer-Cuzick algorithms to assess the prospective risk of breast cancer in women in the kConFab cohort who were unaffected with breast cancer at the time of enrolment in the study. RESULTS: Of kConFab's first 822 families, 518 families had multiple cases of female breast cancer alone, 239 had cases of female breast and ovarian cancer, 37 had cases of female and male breast cancer, and 14 had both ovarian cancer as well as male and female breast cancer. Data are currently held for 11,422 people and germline DNAs for 7,389. Among the 812 families with at least one germline sample collected, the mean number of germline DNA samples collected per family is nine. Of the 747 families that have undergone some form of mutation screening, 229 (31%) carry a pathogenic or splice-site mutation in BRCA1 or BRCA2. Germline DNAs and data are stored from 773 proven carriers of BRCA1 or BRCA1 mutations. kConFab's fresh tissue bank includes 253 specimens of breast or ovarian tissue--both normal and malignant--including 126 from carriers of BRCA1 or BRCA2 mutations. CONCLUSION: These kConFab resources are available to researchers anywhere in the world, who may apply to kConFab for biospecimens and data for use in ethically approved, peer-reviewed projects. A high calculated risk from the Tyrer-Cuzick algorithms correlated closely with the subsequent occurrence of breast cancer in BRCA1 and BRCA2 mutation positive families, but this was less evident in families in which no pathogenic BRCA1 or BRCA2 mutation has been detected.

Adult↗

PubMed1979

[The epidemiological approach to depression (author's transl)].

The epidemiological method is indispensable to the clinical investigator, the practising clinician and the public health worker. In the field of mood disorders epidemiological inquiry has been hampered by the subjective nature of the phenomena under study, the problems of assessment and diagnosis, observer bias and the unrepresentative nature of small population samples. Nontheless, it is argued that the difficulties are similar to those encountered elsewhere in medicine and examples are given of epidemiological contributions to an understanding of depression.

Adolescent↗

PubMedDate not supplied

Beyond LOEL's, p values, and vote counting: methods for looking at the shapes and strengths of associations.

Determining the shape of dose-response relationships, including the possible existence of thresholds, is a central concern in the epidemiology of neurotoxins. Assessing the strengths of associations within a paper, and for the literature as a whole, are also critical concerns. Modern statistical and epidemiologic methods have considerable advantages for answering these questions. This is illustrated by using non-parametric smoothing to look for the existence of thresholds or non-linearities in the neurotoxic effects of lead, the use of multiple analyses and robust methods to test the stability of the association between dentine lead and children's IQ in the study of Needleman et al., 1979, and the examination of the stability of the association between full scale IQ and blood lead across studies. Non-parametric smoothing shows the dose response relationship between McCarthy score and blood lead reported by Bellinger et al., (1991) has no threshold down to blood lead levels of 1 microgram/dl. The association between blood lead and hearing threshold reported by Schwartz and Otto (1991) also has no threshold down to the lowest concentrations seen in that study. The association between dentine lead and IQ in the Needleman et al. (1979) data holds in the full data set with no exclusions and with control for age, is insensitive to exclusions of subjects or inclusions of other covariates, and to the use of robust estimation techniques. Nonparametric smoothing shows the association is supported across the entire range of lead exposure and is not driven by a few outliers. Examination of effect size estimates from the IQ-blood lead studies shows moderately good concordance. This suggests a causal relationship. A meta-analysis of those studies indicates that an increase in blood lead from 10 micrograms/dl to 20 micrograms/dl is associated with a reduction of 2.5 points in full scale IQ. The effect was highly significant.

Animals↗

PubMed1995

Spatial statistical methods in environmental epidemiology: a critique.

Despite recent advances in the available statistical methods for geographical analysis, there are many constraints to their application in environmental epidemiology. These include problems of data availability and quality, especially the lack in most situations of environmental exposure measurements. Methods for disease 'cluster' investigation, point source exposures, small-area disease mapping and ecological correlation studies are critically reviewed, with the emphasis on practical applications and epidemiological interpretation. It is shown that, unless dealing with rare diseases, high specificity exposures and high relative risks, cluster investigation is unlikely to be fruitful, and is often complicated by the post hoc nature of such studies. However, it is recognized that in these circumstances proper assessment of the available data is often required as part of the public health response. Newly available methods, particularly in Bayesian statistics, offer an appropriate framework for geographical analysis and disease mapping. Again, it is uncertain whether they will give important clues as to aetiology, although they do give valuable description. Perhaps the most satisfactory approach is to test a priori hypotheses using a geographical database, although problems of interpretation remain.

Adult↗

PubMed2003

Multilocus variable-number tandem repeat analysis distinguishes outbreak and sporadic Escherichia coli O157:H7 isolates.

Escherichia coli O157:H7 is a major cause of food-borne illness in the United States. Outbreak detection involves traditional epidemiological methods and routine molecular subtyping by pulsed-field gel electrophoresis (PFGE). PFGE is labor-intensive, and the results are difficult to analyze and not easily transferable between laboratories. Multilocus variable-number tandem repeat (VNTR) analysis (MLVA) is a fast, portable method that analyzes multiple VNTR loci, which are areas of the bacterial genome that evolve quickly. Eighty isolates, including 21 isolates from five epidemiologically well-characterized outbreaks from Pennsylvania and Minnesota, were analyzed by PFGE and MLVA. Strains in PFGE clusters were defined as strains that differed by less than or equal to one band by using XbaI and the confirmatory enzyme SpeI. MLVA was performed by comparing the number of tandem repeats at seven loci. From 6 to 30 alleles were found at the seven loci, resulting in 64 MLVA types among the 80 isolates. MLVA correctly identified the isolates from all five outbreaks if only a single-locus variant was allowed. MLVA differentiated strains with unique PFGE types. Additionally, MLVA discriminated strains within PFGE-defined clusters that were not known to be part of an outbreak. In addition to being a simple and validated method for E. coli O157:H7 outbreak detection, MLVA appears to have a sensitivity equal to that of PFGE and a specificity superior to that of PFGE.

Base Sequence↗

PubMed1993

Neurotoxic syndromes and occupational exposure to solvents.

Neurotoxic syndromes due to occupational solvent exposure present a worldwide health problem, the magnitude of which varies from country to country. Apart from the relatively clear-cut exposure-effect relationships in acute solvent intoxications, those caused by long-term, low-level occupational exposure to solvents are more difficult to detect. Controversial opinions and even debate are frequently encountered in literature on this matter. This is partly due to differences in neurobehavioral methods used, partly to difficulties in obtaining accurate information about exposure. These effects can be studied in humans using biochemical, clinical, and epidemiological methods. It is thus quite conceivable that direct comparison of the results obtained by different methods is not always possible. Moreover, exposure to a variable mixture of solvents is frequent in an occupational setting which is problematic from the toxicological point of view. The clinical pictures of "chronic" occupational solvent intoxications are, with few exceptions, quite nonspecific in nature and share several common features regardless of the underlying chemical exposure. The development of manifest disease is insidious and high interindividual variation of symptoms and signs exists. Some solvents cause primarily peripheral neuropathy. Deterioration in many psychological and neurophysiological functions can be seen. The most common subjective symptoms of solvent intoxication are headache, tiredness, memory disturbances, and dizziness. Clinical findings comprise signs of the central nervous system depression (psychoorganic syndrome, tiredness), dizziness, disturbances in coordination, and general neurasthenic signs. From the clinical point of view, it is important to define the criteria for a diagnosis. In different countries the diagnostic criteria for solvent intoxication may vary considerably, which provides additional difficulties in interpreting the results of studies in this field.

Central Nervous System↗

PubMed1988

The contribution of the IARC monographs program to the identification of cancer risk factors.

The differences between cancers that occur as a consequence of occupational exposure and other cancers are not only their preventability but, more importantly, their social unacceptability. Occupational cancer occurs, by definition, among individuals who have been exposed to carcinogens because of their occupation, and most, if not all, of these individuals are drawn from the less favoured social classes. This is probably one reason why mortality from cancer and from all causes is greater in people in classes IV and V than in those in I and II. We cannot precisely quantify the proportion of cases, among the total number of cancer cases observed, attributable to occupational exposures. It is very likely, however, in some of the most industrialized countries, although not in certain developing countries, that the number of those cancers that are indisputably due to occupational exposure is not increasing and is perhaps decreasing. This is due to the combined effect of two factors: the banning of certain chemicals, as, for instance, aromatic amines--even if this did not take place in all countries and, where it did, not at the same time; and improved working conditions, as, for instance, in the case of vinyl chloride. We do not know, however, to what extent low levels of exposure to which the general population is commonly exposed, as well as workers in occupations where levels of exposure to carcinogens have recently been significantly reduced, play a role in the causation of human cancer. While it is important to stress that a large proportion of the chemicals to which humans are exposed, either because of their occupation or in the general environment, and for which experimental evidence of carcinogenicity is available, have not been the object of epidemiological surveys, it is also important to realize that epidemiological methods are generally insufficient to provide reliable information on risks generated by low levels of exposure. It is certainly important to encourage epidemiological surveillance, but it should at the same time be made clear that the epidemiological approach will never entirely replace the considered use of experimental data in the implementation of primary prevention.

Humans↗

PubMed2005

[Anlysis on features of dead cases with human Streptococcus suis infections].

OBJECTIVE: To describe the clinical and epidemiological features of dead cases with human Streptococcus suis infections, and to find the target population for preventing death and the related indicators. METHODS: Epidemiological investigation on human Streptococcus suis infections was implemented used unified questionnaires. Analysis on dead cases and survival cases (as contrast) was done. RESULTS: The population with highest fatality rate was in 40-49 age group. 97.37% of dead cases had toxic shock syndrome. The mean interval from onset to admission was 0.76 days, and the mean course was 2.11 days. The progression among dead cases was faster than that among survival cases. Chief clinical manifestations of dead cases that are more frequent than survival cases are purpura (73.68%), diarrhea (50.0%), dyspnea (21.05%), conjunctival congestion (34.21%), etc. Renal impairment and liver involvement in dead cases were more significant than that in survival cases. No significant difference between mean incubation period, exposure rates of main risk factors in dead cases and in survival cases was found. CONCLUSION: Preventing toxic shock syndrome might reduce the fatality rate. The target population for preventing death is aged > or = 40. Liver function and renal function testing might be indicators for monitoring the progression of human Streptococcus suis infections.

Adult↗

PubMed2006

[Heritability analysis on skeletal angle III malocclusion].

PURPOSE: To explore the significance of genetic factor in the pathogenesis of skeletal angle III malocclusion. METHODS: A case-control study of 96 probands, 200 controls and their relatives was performed and the data were analyzed with genetic epidemiologic methods. SPSS11.5 software package was used for Chi-square test. RESULTS: The prevalence rates of skeletal angle III malocclusion in the first-degree relatives and second-degree relatives in the proband group were 9.00% and 1.88%,respectively,which were higher than that in the first-degree relatives in the control group(0.96%). The heritability in the first-degree relatives was 0.74+/-0.092.The results of segregation analysis didn't suggest that skeletal angle III malocclusion followed a pattern of autosomal recessive inheritance. CONCLUSION: Skeletal angle III malocclusion has characteristics of polygenetic disease. Genetic factor might play an important role in the pathogenesis of skeletal angle III malocclusion.

Case-Control Studies↗