Extensive Epidemiological Research Research Articles

Socioeconomic status and cardiovascular disease risk

To the Editor: We congratulate Dr A Steptoe and associates on their extensive epidemiological research concerning cardiovascular risk and its association with pathogen burden depending on socioeconomic status.1 Since the...

Seroprevalence of Brucellosis among Risk Population in Gyeongsangbuk-do, 2006

Cases of human brucellosis in Korea have recently increased due to the increasing incidence of bovine brucellosis. The authors conducted this study to elucidate the status of brucellosis through seroepidemiologic study. We selected our study population from a high risk group. We conducted a questionnaire survey and obtained blood samples to determine the seroprevalence of brucellosis antibodies for 10 days in February, 2005. The titers of brucellosis were measured by the combination of standard tube agglutination test (STA) and enzyme-linked immunosorbent assay (ELISA) test. Our study subjects comprised 1,075 cases: 971 livestock workers, 51 veterinarians, and 53 artificial inseminators. In the STA test, 27 cases (2.5%) had titers of greater than or equal to 1:20. Of 1,068 cases (7 cases were excluded due to previous brucellosis), 7 cases of brucellosis were diagnosed with titers of 1:160, giving a seroprevalence of brucellosis of 0.66%. The seroprevalence in the male group was 0.95%, and that of livestock workers, veterinarians, and artificial inseminators was 0.52%, 4.17%, and 0.00%, respectively. The Spearman's correlation coefficient between the positive rate of bovine brucellosis per capita and household and human brucellosis was 0.806 and 0.744, respectively. The concordance rate between the Korea National Institute of Health and the Gyeongsangbuk-do Institute of Health and Environment by the STA and ELISA tests was 94.7% and 100.0%, respectively. The study results indicated in higher seroprevalence rate among veterinarians than among livestock workers and artificial inseminators. Because veterinarians may be exposed to this high risk, effective working guidelines for veterinarians to guard against brucellosis must be developed. Moreover, more extensive epidemiologic research for laboratory workers and meat handlers is needed.

Neurotoxicants, Micronutrients, and Social Environments: Individual and Combined Effects on Children's Development.

-Systematic research evaluating the separate and interacting impacts of neurotoxicants, micronutrients, and social environments on children's cognition and behavior has only recently been initiated. Years of extensive human epidemiologic and animal experimental research document the deleterious impact of lead and other metals on the nervous system. However, discrepancies among human studies and between animal and human studies underscore the importance of variations in child nutrition as well as social and behavioral aspects of children's environments that mitigate or exacerbate the effects of neurotoxicants. In this monograph, we review existing research on the impact of neurotoxic metals, nutrients, and social environments and interactions across the three domains. We examine the literature on lead, mercury, manganese, and cadmium in terms of dispersal, epidemiology, experimental animal studies, effects of social environments, and effects of nutrition. Research documenting the negative impact of lead on cognition and behavior influenced reductions by the Center for Disease Control in child lead-screening guidelines from 30 micrograms per deciliter (μg/dL) in 1975 to 25 μg/dL in 1985 and to 10 μg/dL in 1991. A further reduction is currently being considered. Experimental animal research documents lead's alteration of glutamate-neurotransmitter (particularly N-methyl-D-aspartate) activity vital to learning and memory. In addition, lead induces changes in cholinergic and dopaminergic activity. Elevated lead concentrations in the blood are more common among children living in poverty and there is some evidence that socioeconomic status influences associations between lead and child outcomes. Micronutrients that influence the effects of lead include iron and zinc. Research documenting the negative impact of mercury on children (as well as adults) has resulted in a reference dose (RfD) of 0.1 microgram per kilogram of body weight per day (μg/kg/day). In animal studies, mercury interferes with glutamatergic, cholinergic, and dopaminergic activity. Although evidence for interactions of mercury with children's social contexts is minimal, researchers are examining interactions of mercury with several nutrients. Research on the effects of cadmium and manganese on child cognition and behavior is just beginning. Experimental animal research links cadmium to learning deficits, manganese to behaviors characteristic of Parkinson's disease, and both to altered dopaminergic functioning. We close our review with a discussion of policy implications, and we recommend interdisciplinary research that will enable us to bridge gaps within and across domains.

Diverging prevalence trends of atopic disorders in Norwegian children. Results from three cross‐sectional studies

During the last decades there has been extensive epidemiological research to explore the increasing prevalence of asthma and allergy in childhood. The worldwide variations in prevalence of these diseases necessitate regional rapports. Furthermore, time-trend analyses with comparable methods are important in order to monitor the rapidly changing prevalence of these diseases. Three cross-sectional questionnaire-based studies of asthma and allergy in schoolchildren were conducted in the counties of Troms and Finnmark, in northern Norway in 1985, 1995 and 2000. The two former studies included children from randomly selected primary schools (n = 1794/1985, n = 1432/1995). The latter study was a part of ISAAC-II Europe study (n = 3853). Identical items of asthma and allergy were employed. The analyses comprised only children 9-11 years of age. The prevalence of asthma was 9.3, 13.2 and 13.8% in 1985, 1995 and 2000, respectively. However, great gender differences were detected; the prevalence of asthma increased in males from 1995 to 2000, from 14.1 to 17.0%, RR = 1.2 (95% CI 1.0-1.5), but decreased in females 1995 to 2000, from 12.3 to 10.5%, RR = 0.9 (95% CI 0.7-1.1). Furthermore, in children with asthma, a changing trend was found in the external factors that perceived symptoms, from typical allergens towards other, unspecific agents. The prevalence of self-reported atopic eczema/dermatitis syndrome (AEDS) was 13.4, 21.1 and 20.8% in 1985, 1995 and 2000, respectively. The prevalence of self-reported allergic rhinoconjunctivitis was in 16.5, 24.7 and 29.6% 1985, 1995 and 2000, respectively, RR (2000/1995) = 1.2 (95% CI 1.1-1.3). The prevalence of asthma in girls has reached a plateau and even decreased from 1995 to 2000 which is in contrast to the asthma prevalence in boys that tends to continuously increase. The prevalence of AEDS which increased substantially between 1985 and 1995 did not change from 1995 to 2000. However, the prevalence of allergic rhinoconjunctivitis increased steadily from 1985, 1995 to 2000.

Trichloroethylene: Johnson et al.’s Response

Trichloroethylene: Johnson et al.’s Response

Bloodborne and sexually transmitted infections in drug abusers in the United States, Latin America, the Caribbean, and Spain.

In the United States, approximately 1 million Americans are infected with human immunodeficiency virus (HIV), and several thousand new infections are reported each year. More than one-third of cases of acquired immunodeficiency syndrome (AIDS) are associated with injection drug use. An estimated 1.8 million adults and children are currently living with HIV in Latin America and the Caribbean, and injection drug abuse remains a major factor in initial exposures to HIV in these parts of the world. Although only 3 cases of AIDS related to drug abuse have been reported in Bolivia, a country with a nascent epidemic, >19,000 cases of AIDS have been reported in Argentina and >22,000 in Brazil, with a significant number associated with injection drug use. Extensive epidemiological and clinical research has been conducted in the United States and elsewhere to determine the extent and nature of the problem and to design and develop interventions (prevention and treatment) for drug abusers infected with HIV. The articles in this supplement present a current view of the nature and extent of the bloodborne and sexually transmitted infections in drug abusers and their partners in the Western Hemisphere.

The reliability of perinatal and neonatal mortality rates: differential under-reporting in linked professional registers vs. Dutch civil registers.

Official Dutch perinatal mortality rates are based on birth and death certificates. These civil registration data are not detailed enough for international comparisons or extensive epidemiological research. In this study, we linked and extrapolated three national, incomplete, professional registers from midwives, obstetricians and paediatricians, containing detailed perinatal information. This linkage and extrapolation resulted in one detailed professional database which is representative of all Dutch births and from which gestational age-specific perinatal mortality rates could be calculated. The reliability of these calculated mortality rates was established by comparing them with the rates derived from the national civil registers. The professional database reported more perinatal deaths and fewer late neonatal deaths than the civil registers. The under-reporting in the civil registers amounted to 1.2 fewer perinatal deaths per 1000 births and was most apparent in immature newborns. We concluded that under-reporting of perinatal and neonatal deaths depends on the data source used. Mortality rates for the purpose of national and international comparison should, therefore, be defined with caution. This study also demonstrated that combining different incomplete professional registers can result in a more reliable database containing detailed perinatal information. Such databases can be used as the basis for extensive perinatal epidemiological research.

THE EPIDEMIOLOGY OF RHEUMATOID ARTHRITIS

Studies of the descriptive epidemiology of RA indicate a population prevalence of 0.5% to 1% and a highly variable annual incidence (12-1200 per 100,000 population) depending on gender, race/ethnicity, and calendar year. Secular trends in RA incidence over time have been shown in several studies, supporting the hypothesis of a host-environment interaction. People with RA have a significantly increased risk of death compared with age- and sex-matched controls without RA from the same community. The determinants of this excess mortality remain unclear; however, reports suggest increased risk from gastrointestinal, respiratory, cardiovascular, infectious, and hematologic diseases among RA patients compared with controls. Despite extensive epidemiologic research, the etiology of RA is unknown. Several risk factors have been suggested as important in the development or progression of RA. These include genetics, infectious agents, oral contraceptives, smoking, and formal education. Epidemiologic research is an essential contributor to our understanding of RA.

Information and Social Support Regarding Breastfeeding: A Survey of Mothers in Seoul, South Korea

Background. Pediatric societies throughout the world recommend breastfeeding as the optimal form of infant nutrition. This recommendation is based on extensive epidemiologic research that documents the health, developmental, psychological, social, economic, and environmental benefits to infants, mothers, families, and society. The purpose of this study was to examine breastfeeding information and emotional support received by mothers prenatally, hospital breastfeeding practices, and the relationship between information and support received and breastfeeding initiation and planned feeding method post discharge from the hospital. Methods. A 36-item questionnaire was distributed during the Spring 2000 to mothers who delivered babies at maternity centers in Seoul, South Korea. A sample of 52 mothers was surveyed at the time of hospital discharge. The questionnaire was developed based on the literature and reviewed by experts including internationally board certified lactation consultants, a nutritionist, and perinatal nurses. The survey instrument consists of five components: sociodemographic information, breastfeeding information received by mothers prenatally, emotional support regarding the mothers’ infant feeding choice, breastfeeding initiation and supplementation, and hospital breastfeeding practices. Results. Fifty-two breastfeeding mothers at three hospitals completed the survey. The majority of the mothers were 26 to 35 years of age, college graduates, married, had uncomplicated vaginal or planned cesarean deliveries, and primiparas. Forty-nine mothers responded that they decided to breastfeed during their pregnancy. Mothers reported that the information they received during pregnancy was provided primarily by their mothers, or friends and other relatives. The majority of mothers reported that others influenced their infant-feeding decision. Forty mothers reported receiving emotional support for their infant feeding choice during their pregnancy with mothers or mothers-in-law and friends providing the greatest support. Discussion. Women obtain information prenatally about breastfeeding from many sources-family, friends, written materials, prenatal classes, and health care professionals. There are benefits and drawbacks to information received from multiple sources. Additionally, research has shown that a woman’s infant-feeding decision is affected by the type of professional and social support the mother receives. Postpartum professional support for new breastfeeding mothers encompasses multiple dimensions ranging from a follow-up telephone call from the hospital nursing staff to referral to a community resource. Prenatal breastfeeding education on a community-wide basis can provide essential information for future mothers, families, and community support networks. Additional research needs to be done exploring the impact of prenatal, postpartum, and post-discharge support for women on breastfeeding initiation and duration rates.

60 Hz EMF health effects-a scientific uncertainty

Extensive epidemiological and laboratory research has been conducted over the last 15 years on the biological and health consequences of exposure to ELF EMFs. Some epidemiological studies have found weak associations between exposure to power-frequency EMFs and some forms of cancer, such as leukemia; while other studies have failed to find such associations. The primary limitation with most epidemiological studies has been with the methods of exposure assessment. Rigorous methods of exposure assessment that can be associated with biological effects are clearly needed. Epidemiological studies also continue to suffer from significant methodological difficulties associated with the effects of confounding factors. These difficulties hinder interpretation and acceptance of epidemiological findings. Laboratory studies have noted a wide variety of interesting biological effects resulting from exposure to power-frequency EMFs. The most significant and replicated findings are an apparent change in ion efflux at cell membranes in response to limited ranges and intensities of ELF electric fields, an effect of ELF magnetic fields on melatonin production, and effects on enzyme activity. Several concerns exist with regard to the laboratory findings. One concern is that the field strengths used are often orders of magnitude greater than commonly encountered in the home or office. Another concern is that much of the laboratory evidence remains to be independently confirmed. Lastly, a credible mechanism by which commonly encountered (milligauss) power-frequency EMFs could produce human health effects such as cancer still needs to be developed. Thus, the significance of the laboratory findings to human health is questionable. Though the evidence on ELF EMF health effects is mixed, it cannot be dismissed out of hand. >

Pathology of the vulva and vagina

Extensive clinical, epidemiologic and pathologic research published in the past year has enhanced our understanding of the pathogenesis and natural history of human papillomavirus induced female genital tract lesions, and refined diagnostic and therapeutic modalities in management of these patients. Current experience with vulvar intraepithelial neoplasia as well as diagnosis and treatment of squamous cell carcinoma of the vagina and vulva are discussed. Advanced imaging techniques and immunohistochemical studies are employed in diagnosis and classification of less common neoplasms. New antibiotics and potent topical steroids are available for treatment of inflammatory vulvovaginitis, particularly in cases of recurrent candidiasis and lichen sclerosus. Persistent or resistant vulvovaginitis may benefit from an interdisciplinary approach to diagnosis and treatment.

Transcultural counselling and psychotherapy in the 1990s

Abstract Transcultural counselling has its origins in practice rather than theory. There still remains a unified method to develop, and extensive epidemiological and clinical research to carry out, The growing body of work in the field of mental illness and racism, however, has encouraged clinical counsellors in the UK to describe, prescribe, develop and publish their work much more widely. Some recent developments are outlined against the background of political and social changes in Britain in the nineties. Implications for research, training and service delivery are examined.

Transcultural Counselling and Psychotherapy in the 1990s

Abstract Transcultural counselling has its origins in practice rather than theory. There still remains a unified method to develop, and extensive epidemiological and clinical research to carry out, The growing body of work in the field of mental illness and racism, however, has encouraged clinical counsellors in the UK to describe, prescribe, develop and publish their work much more widely. Some recent developments are outlined against the background of political and social changes in Britain in the nineties. Implications for research, training and service delivery are examined.

Polymedicine: known and unknown drug interactions.

Despite more than 15 years of extensive scrutiny, adverse drug interactions, especially in the elderly, remain a problem for the clinician. A two-pronged approach is suggested to contend with drug interactions: detection or avoidance of known drug interactions; and predictions and characterization of hitherto unknown interactions. The former approach is aided by critical reference sources on the subject and the use of drug interaction screening aids such as drug interactions alert lists or rotating drug discs. Computers are becoming increasingly important not only for the detection of potential drug interactions but also for the delineation of drug therapy options. Ultimately, computers can be used to predict interactions on the basis of physiochemical, pharmacokinetic, and pharmacodynamic data. For the present, extensive epidemiologic research programs can serve to ferret out interactions. Limited accessibility to such program data bases mandates a high index of suspicion in prepared and well-informed observers if the drug interaction problem is to be dealt with.