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It is well recognized that both maternal and fetal genes could contribute to susceptibility for obstetric complications. Logistic regression models are usually adopted to model the separate or joint action of maternal and fetal lo...
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It is well recognized that both maternal and fetal genes could contribute to susceptibility for obstetric complications. Logistic regression models are usually adopted to model the separate or joint action of maternal and fetal loci with case-control data. The standard likelihood ratio tests (LRTs) can be used to test the significance of appropriate odds ratio parameters. This method, although simple to implement, fails to exploit a unique feature of genetic epidemiology studies of obstetric complications. Specifically, it does not take into consideration the correlation between the maternal and offspring genomes. We propose novel LRT that take advantage of this information by incorporating the fact that half of a child's genome is inherited from the mother. Our methods have substantially improved power for detecting marginal, main, and interactive maternal and fetal genotype effects, as evidenced by results from extensive simulation studies. We demonstrate our new methods by applying them to the analysis of data from a pilot study of preeclampsia.
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Breast cancer incidence is higher in developed countries with higher rates of estrogen receptor positive (ER+) tumors. ER+ tumors are caused by estrogenic exposures although known exposures explain approximately 50% of breast canc...
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Breast cancer incidence is higher in developed countries with higher rates of estrogen receptor positive (ER+) tumors. ER+ tumors are caused by estrogenic exposures although known exposures explain approximately 50% of breast cancer risk. Unknown risk factors causing high breast cancer incidence exist that are estrogenic and development-related. Xenoestrogens are such risk factors but are difficult to study since developed countries lack unexposed populations. Developing countries have urban-rural populations with differential exposure to xenoestrogens. This study assessed urban-rural breast cancer incidence classified by hormone receptor status using data from Gharbiah population-based cancer registry in Egypt from 2001 to 2006. Urban ER+ incidence rate (per 100,000 women) was 2-4 times (IRR = 3.36, 95% CI = 4.84, 2.34) higher than rural incidence rate. ER-incidence rate was 2-3 times (IRR = 1.86, 95% CI = 2.38, 1.45) higher in urban areas than in rural areas. Our findings indicate that urban women may probably have a higher exposure to xenoestrogens.
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Genetic association studies of obstetric complications may genotype case and control mothers, or their respective newborns, or both case-control mothers and their children. The relatively high prevalence of many obstetric complica...
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Genetic association studies of obstetric complications may genotype case and control mothers, or their respective newborns, or both case-control mothers and their children. The relatively high prevalence of many obstetric complications and the availability of both maternal and offspring's genotype data have provided motivation to study new methods for testing for deviations from Hardy-Weinberg equilibrium (HWE). We propose four novel test statistics, each of which uses a different type of data as follows: (1) a test using maternal case-control genotype data, (2) a test using offspring genotype data, (3) a combination of the first and second tests, and (4) a test based on the joint classification of case-control maternal-child genotype data. The selection of case and control mothers (and thus their children) is accounted for by weighting both maternal and child contributions to the test statistics with sampling probabilities. Our tests thus do not require that the phenotype be rare as is the case for HWE tests using only controls, and are particularly suitable for genetic association studies of relatively common complications such as premature birth. The third and fourth tests described above utilize both maternal and child genotype data and appropriately account for the correlation between maternal and child genotypes. On the basis of extensive simulation studies to compare the type-I error and power for proposed tests, we recommend the third combined test statistic for routine use in the analysis of case-control studies of mother-child pairs.
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Hepatitis C virus (HCV) infection is gaining increasing attention as a global health crisis. Egypt reports the highest prevalence of HCV worldwide, ranging from 6% to more than 40% among regions and demographic groups. Predicting ...
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Hepatitis C virus (HCV) infection is gaining increasing attention as a global health crisis. Egypt reports the highest prevalence of HCV worldwide, ranging from 6% to more than 40% among regions and demographic groups. Predicting the impact of the epidemic has been difficult because of the long-latency period and low-resource setting. Accordingly, we sought to estimate historic incidence and predict the future impact of HCV using Markov simulation modelling techniques. Age-specific HCV incidence rates (IRs) were estimated using previously acquired age-specific HCV prevalence data. Data for this analysis were from a highly detailed, community-based seroprevalence study from 2003. Future HCV-related morbidity and mortality were estimated using a computer cohort simulation of HCV natural history in the Egyptian population. Population and natural history parameters were defined using results from a meta-analysis and existing comprehensive literature reviews. Incidence model estimates ranged from 2.01 to 25.47 HCV cases per 1000 person-years (PYs). The highest IRs were calculated among those over 35 years of age. Our Markov model predicted 127,821 deaths from chronic liver disease and 117,556 deaths from hepatocellular carcinoma in Egypt over the next 20 years. During this period, it was estimated that HCV would yield 750,210 PY of decompensated cirrhosis, 132,894 PY of hepatocellular carcinoma, and a total loss of 32.86 million years of life compared to a non-infected cohort. Our results support the claim of high HCV incidence in Egypt and suggest that HCV may lead to a substantial health and, consequently, economic burden over the next 10-20 years.
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OBJECTIVE: While antenatal care does not directly contribute to reducing maternal mortality, it may play an indirect role by encouraging women to deliver with a skilled birth attendant or in a health facility. We investigated whet...
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OBJECTIVE: While antenatal care does not directly contribute to reducing maternal mortality, it may play an indirect role by encouraging women to deliver with a skilled birth attendant or in a health facility. We investigated whether the frequency of visits and select characteristics of antenatal care were associated with facility delivery. METHOds: We selected a population-representative sample of households in a rural district of western Tanzania. Women who had given birth within five years were asked about their most recent delivery and antenatal care. RESULTS: Of 1,204 women interviewed, 1,195 (99.3%) made at least one antenatal care visit, while only 438 (36.4%) delivered in a health facility. In adjusted analysis, women were significantly more likely to deliver in a health facility if they attended antenatal care at a government health center (OR 3.17, 95% CI: 1.60-6.30) or a mission facility (OR 2.87, 95% CI: 1.36-6.07), rather than a government dispensary. Women were significantly less likely to deliver in a health facility if their nearest health facility was outside their village (OR 0.38, 95% CI: 0.22-0.66). CONCLUSION: Though facility utilization for antenatal care is frequent, most women who accessed antenatal care did not deliver in a health facility. Women who obtained antenatal care at higher level government facilities or mission facilities, which offered better quality of care, were more likely to deliver in any facility. Improving the quality of antenatal care may improve the health of mothers through encouraging women to return to facilities for delivery.
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OBJECTIVES: To assess the current evidence for the role of breastfeeding in the development of early onset inflammatory bowel disease (IBD) with a systematic review. STUDY DESIGN: An electronic database search was performed (Janua...
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OBJECTIVES: To assess the current evidence for the role of breastfeeding in the development of early onset inflammatory bowel disease (IBD) with a systematic review. STUDY DESIGN: An electronic database search was performed (January 1966-January 2008) with keywords related to IBD and breastfeeding, looking specifically for studies that reported outcome in early-onset disease (<16 years of age) and "any exposure" to breast milk as the variables. Meta-analysis of studies included for review was then performed by using a random effects model, and results were expressed as odds ratios (OR) with 95% CIs. RESULTS: A total of 79 articles were identified, 20 of which were found describing breastfeeding in relation to the development of IBD; 8 of these articles included separate early-onset groups. One study did not describe "any exposure" to breast milk for the early onset group, so 7 studies were included in the meta-analysis. Breast milk exposure had a significant protective effect (OR, 0.69; 95% CI, 0.51-0.94; P = .02) in developing early-onset IBD. A non-significant difference was demonstrated for ulcerative colitis and Crohn's disease individually (OR, 0.72; 95% CI, 0.51-1.02; P = .06; OR, 0.64; 95% CI, 0.38-1.07; P = .09, respectively). CONCLUSIONS: The current evidence demonstrates a possible protective effect for breast milk in the development of early onset IBD. However, the quality of existing data is generally poor. These findings need to be investigated in well-designed prospective studies.
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THE THOUGHT OF BRINGING a new information system up live or taking down an old one and replacing it with something else brings joy to some and fear to others. But to all it brings the certain knowledge that the ways in which tasks...
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THE THOUGHT OF BRINGING a new information system up live or taking down an old one and replacing it with something else brings joy to some and fear to others. But to all it brings the certain knowledge that the ways in which tasks are currently done, the ways in which care is rendered for patients, and the mechanisms through which we communicate with the health care team will certainly and fundamentally change. And although the change may be needed, it is still a change, and that is not a comfortable thought for most of us. In addition, it is known that implementations of these systems can result in unintended consequences, both positive and negative, that can have profound impact on the health care environment and, subsequently, the safety of patients and the efficiency of staff.1 The most significant of these consequences are related to new/more work, workflow, system demands, communications, emotions, and dependence on technology.
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