Study Of Urban Population Research Articles

Risk-factor profiles for chronic diseases of lifestyle and metabolic syndrome in an urban and rural setting in South Africa

BackgroundChronic lifestyle diseases share similar modifiable risk factors, including hypertension, tobacco smoking, diabetes, obesity, hyperlipidaemia and physical inactivity. Metabolic syndrome refers to the cluster of risk factors that increases the risk for developing type 2 diabetes mellitus (DM) and cardiovascular disease.ObjectivesThe study aimed to assess health status and identify distinct risk-factor profiles for both chronic lifestyle diseases and metabolic syndrome in rural and urban communities in central South Africa.MethodsThe investigation formed part of the Assuring Health for All in the Free State (AHA-FS) study. During interviews by trained researchers, household socio-demographic and health information, diet, risk factors (i.e. history of hypertension and/or diabetes) and habits (e.g. smoking and inadequate physical activity levels) were determined. Adult participants underwent anthropometric evaluation, medical examination and blood sampling.ResultsThe risk-factor profile for chronic lifestyle diseases revealed that self-reported hypertension and physical inactivity were ranked the highest risk factor for the rural and urban groups respectively. The cumulative risk-factor profile showed that 40.1% of the rural and 34.4% of the urban study population had three or more risk factors for chronic lifestyle diseases. Furthermore, 52.2% of rural and 39.7% of urban participants had three or more risk factors for metabolic syndrome.ConclusionThis study confirmed that the worldwide increase in the prevalence of chronic lifestyle diseases can be attributed to a more sedentary lifestyle, especially illustrated in the urban study population, and increasing obesity. The rural study population had a higher prevalence of risk factors for metabolic syndrome.

Differentiation of African Components of Ancestry to Stratify Groups in a Case–Control Study of a Brazilian Urban Population

Balancing the subject composition of case and control groups to create homogenous ancestries between each group is essential for medical association studies. We explored the applicability of single-tube 34-plex ancestry informative markers (AIM) single nucleotide polymorphisms (SNPs) to estimate the African Component of Ancestry (ACA) to design a future case-control association study of a Brazilian urban sample. One hundred eighty individuals (107 case group; 73 control group) self-described as white, brown-intermediate or black were selected. The proportions of the relative contribution of a variable number of ancestral population components were similar between case and control groups. Moreover, the case and control groups demonstrated similar distributions for ACA <0.25 and >0.50 categories. Notably a high number of outlier values (23 samples) were observed among individuals with ACA <0.25. These individuals presented a high probability of Native American and East Asian ancestral components; however, no individuals originally giving these self-described ancestries were observed in this study. The strategy proposed for the assessment of ancestry and adjustment of case and control groups for an association study is an important step for the proper construction of the study, particularly when subjects are taken from a complex urban population. This can be achieved using a straight forward multiplexed AIM-SNPs assay of highly discriminatory ancestry markers.

High serum uric acid level and low urine pH as predictors of metabolic syndrome: a retrospective cohort study in a Japanese urban population

The objective of this study was to evaluate whether hyperuricemia, acidic urine, or their combination predicts metabolic syndrome (MetS). In study 1, 69 094 subjects who received a general health checkup between 1985 and 2005 were included in a cross-sectional study of serum uric acid (SUA) and urine pH in relation to MetS. In study 2, the association of SUA and urine pH with MetS development over a 5-year period was evaluated in 5617 subjects with body mass index less than 25 kg/m 2 at the first examination. In study 1, higher SUA and lower urine pH were both positively correlated to MetS status ( P < .001). The combination of high SUA and low urine pH was significantly associated with higher MetS prevalence compared with the combination of low SUA and high urine pH (odds ratio, 3.383; 95% confidence interval [CI], 3.034-3.784 in men; odds ratio, 4.000; 95% CI, 2.992-5.452 in women). In study 2, the top quartile of SUA levels was associated with higher MetS development compared with the bottom quartile during the 5-year period in men (hazard ratio [HR], 1.793; 95% CI, 1.084-2.966; P = .023). In women, the HR was 3.732 (95% CI, 0.391-35.62; P = .252) for the upper vs the lower half of SUA levels. For urine pH, the HR was 1.955 (95% CI, 1.089-3.509; P = .025) for the bottom vs the top quartile in men. A likelihood ratio test confirmed that high SUA and low urine pH act synergistically in the development of MetS. High SUA, low urine pH, and their combination are predictive risk factors for MetS development.

Convergence of Prevalence Rates of Diabetes and Cardiometabolic Risk Factors in Middle and Low Income Groups in Urban India: 10-Year Follow-Up of the Chennai Urban Population Study

The aim of this study was to look for temporal changes in the prevalence of diabetes and cardiometabolic risk factors in two residential colonies in Chennai. Chennai Urban Population Study (CUPS) was carried out between 1996-1998 in Chennai in two residential colonies representing the middle income group (MIG) and lower income group (LIG), respectively. The MIG had twice the prevalence rate of diabetes as the LIG and higher prevalence rates of hypertension, obesity, and dyslipidemia. They were motivated to increase their physical activity, which led to the building of a park. The LIG was given standard lifestyle advice. Follow-up surveys of both colonies were performed after a period of 10 years. In the MIG, the prevalence of diabetes increased from 12.4 to 15.4% (24% increase), while in the LIG, it increased from 6.5 to 15.3% (135% increase, p < .001). In the LIG, the prevalence rates of central obesity (baseline vs follow-up, male: 30.8 vs 50.9%, p < .001; female: 16.9 vs 49.8%, p < .001), hypertension (8.4 vs 20.1%, p < .001), hypercholesterolemia (14.2 vs. 20.4%, p < .05), and hypertriglyceridemia (8.0 vs 23.5%, p < .001) significantly increased and became similar to that seen in the MIG. There is a rapid reversal of socioeconomic gradient for diabetes and cardiometabolic risk factors in urban India with a convergence of prevalence rates among people in the MIG and LIG. This could have a serious economic impact on poor people in developing countries such as India.

Rural-urban differences of neonatal mortality in a poorly developed province of China

BackgroundThe influence of rural-urban disparities in children's health on neonatal death in disadvantaged areas of China is poorly understood. In this study of rural and urban populations in Gansu province, a disadvantaged province of China, we describe the characteristics and mortality of newborn infants and evaluated rural-urban differences of neonatal death.MethodsWe analyzed all neonatal deaths in the data from the Surveillance System of Child Death in Gansu Province, China from 2004 to 2009. We calculated all-cause neonatal mortality rates (NMR) and cause-specific death rates for infants born to rural or urban mothers during 2004-09. Rural-urban classifications were determined based on the residence registry system of China. Chi-square tests were used to compare differences of infant characteristics and cause-specific deaths by rural-urban maternal residence.ResultsOverall, NMR fell in both rural and urban populations during 2004-09. Average NMR for rural and urban populations was 17.8 and 7.5 per 1000 live births, respectively. For both rural and urban newborn infants, the four leading causes of death were birth asphyxia, preterm or low birth weight, congenital malformation, and pneumonia. Each cause-specific death rate was higher in rural infants than in urban infants. More rural than urban neonates died out of hospital or did not receive medical care before death.ConclusionsNeonatal mortality declined dramatically both in urban and rural groups in Gansu province during 2004-09. However, profound disparities persisted between rural and urban populations. Strategies that address inequalities of accessibility and quality of health care are necessary to improve neonatal health in rural settings in China.

An analysis of urban population structure and dynamics through the automated management of the registry office

1. The issue of limitations in generating information in current public demographic documentation has been repeatedly raised by experts for a long time, with regard to experimental researches on population structure, movement and territorial distribution which, besides presenting their own independent scientific content, most of the time represent a basis and a necessary condition for every modern socio-economic survey. To the purpose of such surveys, the lack of a reference to municipal units as a maximum term of specification for demographic data, has been particularly stressed several times. In fact, while this criterion prevents from tracing back the analysis of population phenomena to homogeneous geo-economic areas, which are identifiable within a borough or partially belonging to several boroughs, at the same time, in comparison to big cities, it makes it completely impossible to make an in-depth and systematic study of urban population’s settlement and demographic behaviour. Rather than being caused by flaws in scientific research, these limitations and insufficiency of demographic data sources have so far mainly originated from practical factors, which are linked to the elaboration and classification, in main offices, of a large mass of data deriving from censual surveys or obtained through current data collection. However, nowadays it seems urgent to reconsider from a technical and organizational point of view the issue of statistical-demographic records, whose generation has to be done in time scales and forms that are in line with scientific research requirements and with the operational demands of our times. The way to be followed is an effective use of modern computers in order to adapt the management of public statistical services to the new opportunities they have opened in terms of fast time scales and affordable costs for the processing of large quantities of data and basic information.

Prevalence of dental caries and treatment needs for school going children in rural and urban areas of Guntur District, Andhra Pradesh

Background and Objective: Dental caries is the most prevalent dental affliction of childhood and the most common cause of tooth loss in children. Even though many caries prevalence studies have been conducted in different parts of the country, still there is a great deficiency in comparative studies between urban and rural population, particularly in southern Indian states. Hence the objective of this study was to provide the baseline data of caries prevalence. Materials and Methods: A total of 1862 children of both the sexes in the age groups between 7-12yrs and 13-16yrs from various government residential schools in rural and urban areas of Guntur district were examined using WHO (1997) criteria and the data was analyzed. Results: The overall prevalence of caries in the study population was 45.91%.In rural population, 47.04% of children had caries and mean deft/DMFT was 2.637 where as in urban population, 40.52% had caries and mean deft/DMFT was 2.723.Though the caries prevalence was more in rural population, DMFT scores was slightly high in urban study population when compared to rural study population, but it was not statistically significant. The decayed component contributed maximum to total DMFT .Overall, caries was more prevalent among males and prevalence of dental caries was increasing with advancement of age. Regarding treatment needs, 50.32% of rural children and 45.52% of urban children required dental treatment for varies reasons and it is in accordance with dental caries prevalence of different age groups. Conclusion: Dental caries showed to be a significant health issue in the school children requiring immediate attention.

A longitudinal study of epilepsy in Kolkata, India

This study aimed to determine the prevalence, incidence, and mortality rates of epilepsy in the city of Kolkata, India. This is the first such longitudinal study in a heterogeneous urban Indian population. A two-stage door-to-door survey of a stratified random sample was undertaken within the municipal limits of Kolkata. Trained field workers detected and interviewed the cases using a simple screening questionnaire, and the detailed follow-up was done by neurologists. The survey was conducted annually for five consecutive years from March 2003 through February 2008. A total of 52,377 (52.74% men) individuals were screened. There were 309 prevalent and 66 incident cases of active epilepsy. The prevalence and average annual incidence rate (AAIR) with 95% confidence interval (CI), age-standardized to World Standard Population, were 572.8 (509.79-641.54) per 100,000 and 27.27 (21.03-34.80) per 100,000 per year, respectively. The age-specific incidence rates of epilepsy showed bimodal distribution. During the 5-year period, 20 cases of active epilepsy died. The average annual mortality rate (AAMR) was 7.63 (95% CI 4.45-11.26) per 100,000 population per year. Compared to the general population of Kolkata, the all-cause standardized mortality ratio (SMR) for persons with epilepsy was 2.58 overall (men 3.67; women 1.77). There was no significant difference between slum and nonslum dwellers in epidemiologic parameters. The AAIR of epilepsy is comparable to that observed in developed countries, but AAMR is higher. The all-cause SMR for epilepsy relative to the general population is, however, similar to that of developed nations.

Prevalência de diabetes melito e fatores associados em população urbana adulta de baixa escolaridade e renda do sertão nordestino brasileiro

Diabetes mellitus (DM) is a public health problem in Brazil. The objective of this study was to investigate the prevalence of DM and its relation with socio-demographic features and other cardiovascular risk factors in a adult population from the wilderness of Pernambuco, Brazil. In 2008/2009 a cross-sectional study in the adult urban population of Canãa district, city of Triunfo, in the wilderness of Pernambuco/Brazil was conducted. A representative sample of 198 individuals, with average age of 57.7 years, 80% with primary education and 81.3% with a monthly income of less than 1 minimum wage was randomly selected. A prevalence of diabetes of 13.6% and 7.6% of disglycemia (6.6% of impaired fasting glycemia, and 1.0% of impaired glucose tolerance) was found. Among those with diabetes, 24% had no prior diagnosis. Among diabetics, metabolic syndrome (MS) and arterial hypertension (AH) were diagnosed in 87.5% and 68%, respectively. Besides these, there was a positive and significant association between DM and BMI, and between DM and MS. These data demonstrate a high prevalence of DM in the adult urban population from the wilderness of Pernambuco/Brazil. These results as well as their association with obesity and MS, indicate that more effective interventions are necessary for the prevention of these diseases also outside principal urban centers.

Delays incurred during acute myocardial infarction: a comparative study of rural and urban populations in Greece

Treatment delay during myocardial infarction may be due to a number of factors, such as age, sex, socioeconomic status and interpretation of symptoms. However, whether residence plays a role has not been fully investigated and, if known, could provide information that will help target specific populations. This study investigated whether urban and rural residents in Greece differ in the time required to seek and receive medical assistance during acute myocardial infarction, according to their characteristics and the determinants of their delay. This was an observational study (with a structured interview) conducted in one academic and one regional hospital on the island of Crete, Greece, consisting of 348 patients with confirmed myocardial infarction. Patients from rural and urban areas did not differ in the decision time before seeking medical assistance (180 min vs 240 min, p=0.058). Those living in rural areas experienced a longer delay in reaching hospital once they sought assistance (50 min vs 20 min, p<0.0001). The total median delay time (4.25 hours for rural and 4.75 hours for urban patients, p=0.9) was positively affected by female sex and negatively affected by a patient's belief that symptoms were serious, and that they were heart-related. Strategies should be developed to reduce the treatment delay during myocardial infarction for residents of both urban and rural areas, especially for women. Patients interpreting symptoms as being serious and originating from the heart are important for a shorter delay. A better health system is needed in rural Greece in order to deal more effectively with medical emergencies such as myocardial infarction.

Dietary exposure to essential and toxic trace elements from a Total diet study in an adult Lebanese urban population

This study assesses, by the Total diet study approach, the adequacy of micronutrient intake (Co, Cu, Fe, Mn, Ni, Zn) and the dietary exposure of a Lebanese adult urban population to two toxic elements (Cd, Pb). The foods that made up the average ‘total diet’ were derived from a previous individual consumption survey. A total of 1215 individual foods were collected, prepared and cooked prior to analysis. Analytical quantification was performed using inductively coupled plasma mass spectrometry. Average daily intakes of Co (11.4 μg/day), Cu (1104.19 μg/day), Fe (13.00 mg/day), Mn (2.04 mg/day), Ni (126.27 μg/day) and Zn (10.97 mg/day) were below toxicological reference values and were found to satisfy nutritional recommendations, except for manganese in men and iron in women. Average dietary exposure to Pb and Cd represented 3.2% and 21.7% of the respective provisional tolerable weekly intakes. Estimates of dietary intakes of iron appeared to be inadequate for 63% of adult women. These findings should constitute a current measure of assessing the adequacy and safety of foods consumed in Lebanon and may be a basis for future monitoring studies.

Epidemiology of Cardiovascular Disease in Type 2 Diabetes: The Indian Scenario

Noncommunicable diseases, of which coronary artery disease (CAD) and diabetes top the list, have overtaken communicable diseases with respect to overall mortality, even in developing countries like India. High prevalence rates of diabetes and CAD are seen not only in affluent migrant Indians, but also in those living within the subcontinent. Indeed the epidemic of diabetes and CAD is now spreading to the middle- and lower-income groups in India. The risk for CAD is two to four times higher in diabetic subjects, and in Indians, CAD occurs prematurely, i.e., one to two decades earlier than in the West. Thus there is an urgent need for studies on CAD in diabetic and nondiabetic subjects in India. The Chennai Urban Population Study, a population-based study in Chennai, in South India, showed a prevalence of CAD of 11%, which is 10 times more than what it was in 1970. Clustering of risk factors for CAD such as hyperglycemia, central body obesity, dyslipidemia, and hypertension tends to occur, and interplay of these risk factors could explain the enhanced CAD risk in Indians. Additionally, low-grade inflammation and a possible inherent genetic susceptibility are other contributing factors. Preventive measures such as lifestyle modification with healthy diet, adequate physical activity, and decrease in stress could help prevent the twin epidemics of diabetes and CAD.

Predictors and outcomes of persistent or age‐limited registered criminal behavior: a 30‐year longitudinal study of a Swedish urban population

This study uses data from the longitudinal research program Individual Development and Adaptation, where an entire school-grade cohort of children in a middle-size Swedish city (n approximately 1.300) has been followed from ages 10 to 43 and 48 for women and men, respectively. Our findings indicate that the patterns of offending across the life-course differ between genders, where males seem to initiate their offending earlier than females. Further, there are very few women on a persistent offending-trajectory. Focusing on precursors to as well as consequences of offending as indexed in official registers, our results indicate that individuals in the persistent offender group have the most pronounced adjustment problems in school- as well as in middle age. Individual characteristics and behaviors (e.g., aggression, hyperactivity, antisocial behavior) vary systematically between individuals with different developmental offending patterns. The combination of an unstable upbringing and own antisocial behavior seems to be especially predictive for criminality. For persistent offenders, the prevalence of alcohol and psychiatric problems at adult age is high for males and extremely high for females (nine out of ten and six out of ten for each of the two problem types for females). Further, the importance for adjustment of the two-dimensional variation in the number of crimes committed during adolescence and adult age seems to have been surprisingly well captured by the "crude" division into the four offender groups that were used.

Low genetic variability, female‐biased dispersal and high movement rates in an urban population of Eurasian badgers Meles meles

1. Urban and rural populations of animals can differ in their behaviour, both in order to meet their ecological requirements and due to the constraints imposed by different environments. The study of urban populations can therefore offer useful insights into the behavioural flexibility of a species as a whole, as well as indicating how the species in question adapts to a specifically urban environment. 2. The genetic structure of a population can provide information about social structure and movement patterns that is difficult to obtain by other means. Using non-invasively collected hair samples, we estimated the population size of Eurasian badgers Meles meles in the city of Brighton, England, and calculated population-specific parameters of genetic variability and sex-specific rates of outbreeding and dispersal. 3. Population density was high in the context of badger densities reported throughout their range. This was due to a high density of social groups rather than large numbers of individuals per group. 4. The allelic richness of the population was low compared with other British populations. However, the rate of extra-group paternity and the relatively frequent (mainly temporary) intergroup movements suggest that, on a local scale, the population was outbred. Although members of both sexes visited other groups, there was a trend for more females to make intergroup movements. 5. The results reveal that urban badgers can achieve high densities and suggest that while some population parameters are similar between urban and rural populations, the frequency of intergroup movements is higher among urban badgers. In a wider context, these results demonstrate the ability of non-invasive genetic sampling to provide information about the population density, social structure and behaviour of urban wildlife.

Periodontal diseases and cancer

Chronic periodontitis and aggressive periodontitis are inflammatory forms of periodontal disease (figure) caused by microorganisms from plaque biofilm that forms around the teeth. Chronic inflammation of the periodontium results in continuous release of cytokines, prostaglandins, bacterial toxins, and many other destructive enzymes from cells in the area. This chronic process leads to formation of periodontal pockets and progressive destruction of connective tissue and alveolar bone. 1 Pihlstrom B Michalowicz B Johnson N Periodontal diseases. Lancet. 2005; 366: 1809-1820 Summary Full Text Full Text PDF PubMed Scopus (2535) Google Scholar Chronic periodontitis and aggressive periodontitis are the most common causes of tooth loss in adults. Many studies have shown an association between periodontal diseases and systemic manifestations of cardiovascular disease, diabetes, and premature low-weight birth. 1 Pihlstrom B Michalowicz B Johnson N Periodontal diseases. Lancet. 2005; 366: 1809-1820 Summary Full Text Full Text PDF PubMed Scopus (2535) Google Scholar However, there is no evidence for a causal effect. A recent study assessed periodontitis and premature death in young adults in urban regions of Sweden. 2 Söder B Jin L Klinge B Söder P Periodontitis and premature death: a 16-year longitudinal study in a Swedish urban population. J Periodontal Res. 2007; 42: 361-366 Crossref PubMed Scopus (49) Google Scholar The findings showed that young individuals with periodontitis and missing molar teeth, compared with those with no periodontitis, had increased risk of premature death because of cancer, circulatory, and digestive diseases. In this issue of The Lancet Oncology, Michaud and colleagues 3 Michaud DS Liu Y Meyer M Giovannucci E Joshipura K Periodontal disease, tooth loss, and cancer risk in male health professionals: a prospective cohort study. Lancet Oncol. 2008; 9: 550-558 Summary Full Text Full Text PDF PubMed Scopus (261) Google Scholar present important data from a prospective study that shows an increase in cancer risk in a large population of well-characterised US male health professionals who self-reported having periodontal disease with alveolar bone loss. Their findings showed a significant association between periodontal disease and haematological, kidney, and pancreatic cancer. The cancer risk persisted in individuals who never smoked. In a previous study, 4 Michaud D Joshipura K Giovannucci E Fuchs C A prospective study of periodontal disease and pancreatic cancer in US male health professionals. J Natl Cancer Inst. 2007; 99: 171-175 Crossref PubMed Scopus (205) Google Scholar Michaud and co-workers suggested an association between periodontal disease and pancreatic cancer in the same population of health professionals. They concluded that plausible biological mechanisms, such as systemic inflammation or increased concentrations of carcinogenic compounds (or both) as a result of bacteria in the oral cavity of those with periodontal disease, could be involved in the development of cancer. Furthermore, a recent case–control study suggested that chronic periodontitis is associated with increased risk of developing tongue cancer. 5 Tezal M Sullivan M Reid M et al. Chronic periodontitis and the risk of tongue cancer. Arch Otolaryngol Head Neck Surg. 2007; 133: 450-454 Crossref PubMed Scopus (130) Google Scholar However, other researchers believe that the association between periodontal disease and cancer might be spurious. 6 Hujoel P Drangsholt M Spiekerman C Weiss N An exploration of the periodontitis-cancer association. Ann Epidemiol. 2003; 13: 312-316 Summary Full Text Full Text PDF PubMed Scopus (192) Google Scholar Therefore, future studies that assess in more detail potential mechanisms for the association between periodontal diseases and cancer are warranted. (A) Diagnosis should include clinical presentation, periodontal pocket probings, and radiographical assessment of bone levels. Note that the gingival tissues are red and swollen, and the level of the gingival margins is irregular. (B) Radiograph of top teeth shows only the tips of the roots inserted in alveolar bone (arrow). Periodontal disease, tooth loss, and cancer risk in male health professionals: a prospective cohort studyPeriodontal disease was associated with a small, but significant, increase in overall cancer risk, which persisted in never-smokers. The associations recorded for lung cancer are probably because of residual confounding by smoking. The increased risks noted for haematological, kidney, and pancreatic cancers need confirmation, but suggest that periodontal disease might be a marker of a susceptible immune system or might directly affect cancer risk. Full-Text PDF

Relation between age and coronary heart disease (CHD) risk in Asian Indian patients with diabetes: A cross-sectional and prospective cohort study

Objective Non-migrant Asian Indians have a high prevalence of diabetes and coronary heart disease (CHD). Since the relation between age and CHD risk in this population is not known, the appropriateness of existing age threshold for patients with diabetes to be suitable for primary CHD prevention with statins is not known. We aimed to determine an age threshold above which patients develop a higher risk of CHD and would merit routine statin prescription. Design Cross-sectional analysis of 1087 patients with diabetes from the Chennai Urban Rural Epidemiological Studies (CURES). CHD risk assessment was calculated using the United Kingdom Prospective Study (UKPDS) risk engine, externally validated by using data obtained from the 7-year follow-up cohort of the Chennai Urban Population Study (CUPS). Relation between age and CHD risk was determined and the age threshold for increased CHD risks was calculated using line of best fit. Results UKPDS risk engine overestimates CHD event rates by 50% in this population. Age is a strong independent predictor of CHD risk. Transition from low to moderate-risk category for men and women with diabetes occurred at ages 37 and 50 years, respectively. Sensitivity for fulfilling this CHD risk criteria are 98.7% for men and 87.1% for women. Conclusions Statins should be routinely prescribed to all Asian Indian men and women with diabetes above the ages of 37 and 50 years, respectively. For patients below these age thresholds, decision to initiate statins should be based on patient's individual cardiovascular risk factors. This strategy may facilitate public health efforts to reduce CHD events in India.

Childhood asthma epidemiology: Insights from comparative studies of rural and urban populations

Asthma is one of the most common chronic respiratory disorders. Many epidemiology studies have suggested an increasing trend of asthma in many different regions of the world but the exact reasons explaining such trend remain unclear. Nevertheless, changing environmental factors are most likely important in explaining the trend of asthma. Studies in the past decade have clearly shown a mark difference in the prevalence between urban and rural regions. The consistent findings of a markedly lower prevalence of asthma in children and adults who have been brought up in a farming environment clearly indicate the importance of environmental influence of asthma development. Although the exact protective environmental factors in the rural region remain to be defined, there have been many studies suggesting that early exposure to microbes or microbial products may play a role in modulating the immune system so as to reduce the future risk of asthma and allergies. Advances in the understanding of the genetic predisposition and how these genetic factors may interact with specific environment factors are of paramount importance for the future development of primary preventive strategies for asthma.

An observational study of the relationship between lumbar epidural space depth and body mass index in Michigan parturients

Studies of urban parturient populations demonstrate increasing prevalence of obesity, which contributes to difficult epidural catheter placement. The aim of this study was to characterize the relationship between lumbar epidural space depth and body mass index in United States parturients from Michigan. We studied the records of 2009 parturients at or beyond 36 weeks' gestation. In addition to lumbar epidural space depth and body mass index, we recorded maternal age, gestational age and vertebral interspace of epidural placement. A multi-linear regression model was created with centimeter depth from skin to lumbar epidural space as the dependent variable and body mass index as the independent variable, adjusted for maternal age, gestational age and vertebral interspace. Lumbar epidural space depth was (mean +/- SD) 5.3 cm+/-1.21, with more than 96% of catheters placed at L2-3 or L3-4. Mean body mass index was 31.5+/-6.2 kg/m(2). Mean maternal age was 29.3+/-5.7 years while mean gestational age was 39.3+/-1.3 weeks. In a multi-linear regression model, body mass index and maternal age were significant predictors of centimeter depth. When adjusted for maternal age, gestational age and vertebral interspace of catheter placement, body mass index was associated with an increase in depth (P<0.0001, R(2)=0.3646). Maternal age, when adjusted for body mass index and vertebral interspace, was associated with a decreased depth (P=0.0014). When maternal age, gestational age and vertebral interspace are controlled for, increasing body mass index is associated with increasing depth, while increasing maternal age is associated with decreasing depth.

Impact of the 2004 mass drug administration for the control of lymphatic filariasis, in urban and rural areas of the Western province of Sri Lanka

Lymphatic filariasis is targeted to be eliminated globally, at least as a public-health problem, by 2020. The comprehensive strategy for achieving this goal includes the interruption of the transmission of the causative parasites, by drastically reducing the prevalences of microfilaraemia in at-risk communities. In a descriptive, comparative, cross-sectional and community-based study, the impact of the 2004 mass drug administration (MDA) on filarial infection, in selected areas of the Western province of Sri Lanka, has now been assessed 1-2 and 11 months after the administration of the diethylcarbamazine-albendazole combination employed. Using the cluster-sampling method, urban study populations were selected in the Colombo districts and rural ones were selected in the Gampaha district. After obtaining informed written consent, 2 ml venous blood were collected, between 20.00 and 24.00 hours, from each subject. Personal details and drug compliance in the 2004 MDA were recorded. The samples of 'night' blood were checked for microfilariae, using membrane filtration, and for filarial antigenaemia, using commercial (NOW) immunochromatographic test kits. Eighty-four (4.10%) of the 2034 subjects examined 1-2 months after the 2004 MDA but only four (0.20%) of the 1974 subjects checked 11 months after the MDA were found antigenaemic and/or microfilaraemic (P<0.001). Between the two follow-ups, the overall prevalences of both antigenaemia (4.03% v. 0.15%; P<0.001) and microfilaraemia (0.20% v. 0.05%; P=0.38) fell, although only the reduction in antigenaemia was statistically significant. The prevalence of infection (as indicated by antigenaemia and/or microfilaraemia) fell significantly within each of the two study districts (P<0.001). Although, when the prevalence of infection was high, drug compliance appeared to be an important determinant of the reduction of antigenaemia (P=0.04), the 20% difference in compliance between urban and rural areas had no apparent effect on the corresponding prevalences of infection recorded at either follow-up.

Understanding the differences between contrasting HIV epidemics in east and west Africa: results from a simulation model of the Four Cities Study

Objective: To determine if the differences in risk behaviours, the proportions of males circumcised and prevalences of sexually transmitted infections (STIs) observed in two African cities with low prevalence of...