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Kenneth Hill

Publications and source records attributed to Kenneth Hill.

16 recordsLinked to original sources
PubMed2006

Epidemiologic transition interrupted: a reassessment of mortality trends in Thailand, 1980-2000.

BACKGROUND: In the late 1980s and early 1990s a generalized HIV epidemic affected Thailand which was relatively well controlled by an intensive national campaign by the mid 1990s. The extent to which the epidemic has slowed or possibly reversed the epidemiological transition in Thailand is relatively unknown. METHODS: Under-five mortality rates (U5MR) were determined from various sources and weighted least squares regression conducted to determine U5MR over the years 1980-2000. Direct and indirect estimates of the completeness of death registration were used to estimate mortality levels in those aged more than 5 years for the 1980-90 and 1990-2000 periods. Life tables were constructed using the various estimates to determine changes in life-expectancy between the two time periods. RESULTS: U5MR in Thailand is estimated to have been 58/1000 live births in 1980, declining to 30 in 1990 and to 23 in 2000. The vital registration system clearly underestimates U5MR. Successive surveys of Population Change (SPC) imply coverage of death registration improving from 75-77% in 1985-86 to 95% in 1995-96, partly due to a reliance on self-reported registration in the latter survey. In contrast, the General Growth Balance-Synthetic Extinction Generations (GGB-SEG) method suggests coverage worsening from 78-85% in 1980-90 to 64-72% in 1990-2000. Life tables based on SPC adjustments show continued declines in female, and to a lesser extent, male adult mortality with corresponding increases in life-expectancy at birth of around 6 years for both sexes from 1980-90 to 1990-2000. In contrast, the indirect adjustments suggest a substantial increase in male adult mortality with female adult mortality unchanged; life expectancy decreased by 4 years for males and was only marginally higher in females. CONCLUSION: Given the conflicting evidence a definitive assessment of mortality change in Thailand between 1980 and 2000 is difficult to make. Indirect adjustments, based on demographic methods point to a major reversal in mortality decline among males, and a slowing in females. If adult mortality registration has declined, and given the continued under-registration of infant and child deaths, remedial measures are urgently required if the mortality system is to better inform and monitor health development in Thailand.

Adolescent↗
PubMed2006

Stillbirth rates: delivering estimates in 190 countries.

BACKGROUND: While information about 4 million neonatal deaths worldwide is limited, even less information is available for stillbirths (babies born dead in the last 12 weeks of pregnancy) and there are no published, systematic global estimates. We sought to identify available data and use these to estimate the rates and numbers of stillbirths for 190 countries for the year 2000, and provide uncertainty estimates. METHODS: We assessed three sources of stillbirth data according to specified inclusion criteria: vital registration; demographic and health surveys (DHS), based on a new analysis of contraceptive calendar data; and study reports that include published studies identified through systematic literature searches of more than 30,000 abstracts and unpublished studies. A random effects regression model was developed to predict national stillbirth rates and associated uncertainty intervals. FINDINGS: Data from 44 countries with vital registration (71,442 stillbirths), 30 DHS surveys from 16 countries (2989 stillbirths), and 249 study populations from 103 countries (93,023 stillbirths) met the inclusion criteria. Model-based estimates were used for 128 countries. For 62 countries, the observed values were adjusted by a correction factor derived from the model. The resultant stillbirth rates ranged from five per 1000 in rich countries to 32 per 1000 in south Asia and sub-Saharan Africa. The estimated number of global stillbirths is 3.2 million (uncertainty range 2.5-4.1 million). In light of the data limitations and the conservative approach taken, the real number might be higher than this. INTERPRETATION: The numbers of stillbirths are high and there is a dearth of usable data in countries and regions in which most stillbirths occur, with under-reporting being a major challenge. Although our estimates are probably underestimates, they represent a rigorous attempt to measure the numbers of babies dying during the last trimester of pregnancy. Improving stillbirth data is the first step towards making stillbirths count in public-health action.

Data Collection↗
PubMed2006

How should we measure maternal mortality in the developing world? A comparison of household deaths and sibling history approaches.

OBJECTIVE: A reduction in the maternal mortality ratio (MMR) is one of six health-related Millennium Development Goals (MDGs). However, there is no consensus about how to measure MMR in the many countries that do not have complete registration of deaths and accurate ascertainment of cause of death. In this study, we compared estimates of pregnancy-related deaths and maternal mortality in a developing country from three different household survey measurement approaches: a module collecting information on deaths of respondents' sisters; collection of information about recent household deaths with a time-of-death definition of maternal deaths; and a verbal autopsy instrument to identify maternal deaths. METHODS: We used data from a very large nationally-representative household sample survey conducted in Bangladesh in 2001. A total of 104 323 households were selected for participation, and 99 202 households (95.1% of selected households, 98.8% of contacted households) were successfully interviewed. FINDINGS: The sisterhood and household death approaches gave very similar estimates of all-cause and pregnancy-related mortality; verbal autopsy gave an estimate of maternal deaths that was about 15% lower than the pregnancy-related deaths. Even with a very large sample size, however, confidence intervals around mortality estimates were similar for all approaches and exceeded +/- 15%. CONCLUSION: Our findings suggest that with improved training for survey data collectors, both the sisterhood and household deaths methods are viable approaches for measuring pregnancy-related mortality. However, wide confidence intervals around the estimates indicate that routine sample surveys cannot provide the information needed to monitor progress towards the MDG target. Other approaches, such as inclusion of questions about household deaths in population censuses, should be considered.

Adolescent↗
PubMed2005

Transforming growth factor-beta1 induces Nox4 NAD(P)H oxidase and reactive oxygen species-dependent proliferation in human pulmonary artery smooth muscle cells.

Transforming growth factor-beta1 (TGF-beta1) is abundantly expressed in pulmonary hypertension, but its effect on the pulmonary circulation remains unsettled. We studied the consequences of TGF-beta1 stimulation on freshly isolated human pulmonary artery smooth muscle cells (HPASMC). TGF-beta1 initially promoted differentiation, with upregulated expression of smooth muscle contractile proteins. TGF-beta1 also induced expression of Nox4, the only NAD(P)H oxidase membrane homolog found in HPASMC, through a signaling pathway involving Smad 2/3 but not mitogen-activated protein (MAP) kinases. TGF-beta1 likewise increased production of reactive oxygen species (ROS), an effect significantly reduced by the NAD(P)H oxidase flavoprotein inhibitor diphenylene iodonium (DPI) and by Nox4 siRNAs. In the absence of TGF-beta1, Nox4 was present in freshly cultured cells but progressively lost with each passage in culture, paralleling a decrease in ROS production by HPASMC over time. At a later time point (72 h), TGF-beta1 promoted HPASMC proliferation in a manner partially inhibited by Nox4 small interfering RNA and dominant negative Smad 2/3, indicating that TGF-beta1 stimulates HPASMC growth in part by a redox-dependent mechanism mediated through induction of Nox4. HPASMC activation of the MAP kinases ERK1/2 was reduced by the NAD(P)H oxidase inhibitors DPI and 4-(2-aminoethyl)benzenesulfonyl fluoride, suggesting that TGF-beta1 may facilitate proliferation by upregulating Nox4 and ROS production, with transient oxidative inactivation of phosphatases and augmentation of growth signaling cascades. These findings suggest that Nox4 is the relevant Nox homolog in HPASMC. This is the first observation that TGF-beta1 regulates Nox4, with important implications for mechanisms of pulmonary vascular remodeling.

Cell Proliferation↗
PubMed2005

Maternal, neonatal and community factors influencing neonatal mortality in Brazil.

Child mortality (the mortality of children less than five years old) declined considerably in the developing world in the 1990s, but infant mortality declined less. The reductions in neonatal mortality were not impressive and, as a consequence, there is an increasing percentage of infant deaths in the neonatal period. Any further reduction in child mortality, therefore, requires an understanding of the determinants of neonatal mortality. 209,628 birth and 2581 neonatal death records for the 1998 birth cohort from the city of São Paulo, Brazil, were probabilistically matched. Data were from SINASC and SIM, Information Systems on Live Births and Deaths of Brazil. Logistic regression was used to find the association between neonatal mortality and the following risk factors: birth weight, gestational age, Apgar scores at 1 and 5 minutes, delivery mode, plurality, sex, maternal education, maternal age, number of prior losses, prenatal care, race, parity and community development. Infants of older mothers were less likely to die in the neonatal period. Caesarean delivery was not found to be associated with neonatal mortality. Low birth weight, pre-term birth and low Apgar scores were associated with neonatal death. Having a mother who lives in the highest developed community decreased the odds of neonatal death, suggesting that factors not measured in this study are behind such association. This result may also indicate that other factors over and above biological and more proximate factors could affect neonatal death.

Adolescent↗
PubMed2005

Using indirect methods to understand the impact of forced migration on long-term under-five mortality.

Despite the large numbers of displaced persons and the often-lengthy periods of displacement, little is known about the impact of forced migration on long-term under-five mortality. This paper looks at the Brass Method (and adaptations of this method) and the Preceding Birth Technique in combination with a classification of women by their migration and reproductive histories, in order to study the impact of forced migration on under-five mortality. Data came from the Demography of Forced Migration Project, a study on mortality, fertility and violence in the refugee and host populations of Arua District, Uganda and Yei River District, Sudan. Results indicate that women who did not migrate in a situation of conflict and women who repatriated before the age of 15, had children with the highest under-five mortality rates compared with women who were currently refugees and women who repatriated after the age of 15.

Adolescent↗
PubMed2005

Socioeconomic differentials in supplementation of vitamin A: evidence from the Philippines.

The efficacy of supplementation of vitamin A in child survival has been well-demonstrated. However, the effectiveness of a programme of vitamin A supplementation at the population level has been rarely examined. Understanding how programmes reach disadvantaged children can help improve the design of initiatives of vitamin A supplementation. The differentials in receipt of vitamin A by socioeconomic status were assessed using data from the Philippines. Factors associated with receipt of vitamin A during the last six months were examined using the Philippines Demographic and Health Surveys conducted in 1993 and 1998. In total, 6,970 and 6,118 children aged 12-59 months were included in 1993 and 1998 respectively. Logistic regression was used for identifying associations between the outcome and the household socioeconomic variables. The coverage of national-level vitamin A supplementation increased from 27% in 1993 to 79% in 1998. However, children whose mothers did not complete primary education and children living in poor households were less likely to receive supplementation. This disparity increased between the surveys: the adjusted odds of vitamin A intake by poor households compared to middle-class households declined from 0.73 [95% confidence interval (CI) 0.61-0.87) in 1993 to 0.52 (95% CI 0.42-0.63)] in 1998, resulting in an increased health inequity. The vitamin A programme in the Philippines was not uniformly successful in reaching the most vulnerable children. Approaches targeting vulnerable households or approaches not requiring mothers to travel to distribution centres may be more promising.

Child, Preschool↗
PubMed2004

Probabilistic record linkage and an automated procedure to minimize the undecided-matched pair problem.

Probabilistic record linkage allows the assembling of information from different data sources. We present a procedure when a one-to-one relationship between records in different files is expected but not found. Data were births and infant deaths, 1998-birth cohort, city of São Paulo, Brazil. Pairs for which a one-to-one relationship was obtained and a best-link was found with the highest weight were taken as unequivocally matched pairs and provided information to decide on the remaining pairs. For these, an expected relationship between differences in dates of death and birth registration was found; and places of birth and death registration for neonatal deaths were likely to be the same. Such evidence was used to solve for the remaining pairs. We reduced the number of non-uniquely matched records and of uncertain matches, and increased the number of uniquely matched pairs from 2,249 to 2,827. Future research using record linkage should use strategies from first record linkage runs before a full clerical review (the standard procedure under uncertainty) to efficiently retrieve matches.

Birth Rate↗
PubMed2004

Mortality in China 1964-2000.

This paper uses data from censuses and surveys to re-estimate mortality levels and trends in China from the 1960s to 2000. We use the General Growth Balance method to evaluate the completeness of death reporting above the youngest ages in three censuses of the People's Republic of China from 1982 to 2000, concluding that reporting quality is quite high, and revisit the completeness of death recording in the 1973-75 Cancer Epidemiology Survey. Estimates of child mortality from a variety of direct and indirect sources are reviewed, and best estimates arrived at. Our estimates show a spectacular improvement in life expectancy in China: from about 60 years in the period 1964-82 to nearly 70 years in the period 1990-2000, with a further improvement to over 71 years by 2000. We discuss why survival rates continue improving in China despite reduced government involvement in and increasing privatization of health services, with little insurance coverage.

Adolescent↗
PubMed2004

Traumatic events and symptoms of post-traumatic stress disorder amongst Sudanese nationals, refugees and Ugandans in the West Nile.

OBJECTIVES: To compare the incidence of traumatic events and its association with symptoms of post-traumatic stress disorder in three population groups in northern Uganda and southern Sudan. METHODS: Household and individual level data collected through a single-round cross-sectional demographic survey. SETTING: The sub-counties of Yivu, Odupi and Midia in the northern Ugandan district of Arua and of Otogo in Yei River district in southern Sudan. PARTICIPANTS: Residents of these Ugandan and Sudanese sub-counties were categorized on the basis of citizenship and refugee status (i.e. as Ugandan nationals, Sudanese nationals or Sudanese refugees). The random sample population consisted of 3,323 adults (mean age: 30 years; 75% female) from 1,831 national and refugee households. RESULTS: Sudanese refugees reported the highest number of violent events experienced or witnessed ever and in the past one year . Witnessing of traumatic events, ever and in the past year , significantly predicted PTSD in surveyed population. Sex, age, education and occupation were also significantly associated with the development of PTSD symptoms. The population prevalence of PTSD was estimated to be 48% for Sudanese stayees, 46% for Sudanese refugees and 18% for Ugandan nationals. CONCLUSIONS: Symptoms of PTSD in war-affected Sudanese populations can be partly explained by traumatic event exposures. The high prevalence of violence and symptoms of PTSD in refugee populations highlight the need for better protection and security in refugee settlements. Humanitarian agencies must consider the provision of mental health services for populations affected by war and forced migration.

Adult↗
PubMed2004

Determinants of personal demand for an AIDS vaccine in Uganda: contingent valuation survey.

OBJECTIVE: To assess the factors affecting demand for an HIV/AIDS vaccine among adults in their prime earning and childbearing years and the impact of vaccination on risk behaviour in a high-prevalence, low-income country. METHODS: A contingent valuation survey of 1677 adults aged 18-60 years was conducted in 12 districts in Uganda. Respondents were asked about a hypothetical vaccine to prevent HIV infection. Households were randomly assigned survey questionnaires with one of two levels of vaccine efficacy (50% or 95%) and one of five prices. The influence of demographic characteristics, vaccine efficacy, self-assessed risk of infection, price, and household assets on vaccine demand was assessed using multivariate regression analysis. FINDINGS: Altogether, 94% (1576/1677) of respondents would be willing to be vaccinated with a free HIV/AIDS vaccine; 31% (78/251) would not be willing to be vaccinated at a price of 5000 Ugandan shillings (2.86 U.S. dollars). Household wealth, vaccine price, and risk behaviour were significant determinants of individual demand. Demand was equally high for both low-efficacy and high-efficacy vaccines. Respondents believed that condom use would be slightly less necessary with a high-efficacy vaccine (655/825; 79.4%) than a low-efficacy vaccine (690/843; 81.8%). However, reported condom use with partners other than spouses in the absence of a vaccine was much lower (137/271; 50.6%), with 26% (175/670) of men and 9.5% (96/1007) of women reporting having had partners other than their spouses during the past year. CONCLUSION: The high demand for an AIDS vaccine of any level of efficacy can be explained by the heavy toll of AIDS in Uganda: 72% (990/1371) of respondents had lost a family member to the disease. An AIDS vaccine would be self-targeting: those with a greater chance of becoming infected and spreading HIV would be more likely to seek a vaccine, improving the efficiency of vaccination programmes. However,,high levels of risk behaviour in the population suggest that a low-efficacy vaccine alone would have only a limited impact on the epidemic.

Adolescent↗
PubMed2002

Anti-Hu antibodies in Merkel cell carcinoma.

Anti-Hu antibody is an antineuronal autoantibody found in a subset of patients with paraneoplastic neurological disease. The antibody was first associated with small cell carcinoma of the lung and is most often used as a marker for this neoplasm in patients presenting with suspected paraneoplastic syndromes. Here we report a patient with a multifaceted neurological disorder in the setting of Merkel cell carcinoma. The patient's serum contained antibodies against the Hu antigen, and the expression of the Hu antigen was demonstrated in the patient's tumor.

Aged↗