The Contribution of Declines in Blood Lead Levels to Reductions in Blood Pressure Levels: Longitudinal Evidence in the Strong Heart Family Study

BACKGROUND

Chronic lead exposure is associated with both subclinical and clinical cardiovascular disease. We evaluated whether declines in blood lead were associated with changes in systolic and diastolic blood pressure in adult American Indian participants from the SHFS (Strong Heart Family Study).

METHODS AND RESULTS

Lead in whole blood was measured in 285 SHFS participants in 1997 to 1999 and 2006 to 2009. Blood pressure and measures of cardiac geometry and function were obtained in 2001 to 2003 and 2006 to 2009. We used generalized estimating equations to evaluate the association of declines in blood lead with changes in blood pressure; cardiac function and geometry measures were considered secondary. Mean blood lead was 2.04 μg/dL at baseline. After ≈10 years, mean decline in blood lead was 0.67 μg/dL. In fully adjusted models, the mean difference in systolic blood pressure comparing the highest to lowest tertile of decline (>0.91 versus <0.27 μg/dL) in blood lead was -7.08 mm Hg (95% CI, -13.16 to -1.00). A significant nonlinear association between declines in blood lead and declines in systolic blood pressure was detected, with significant linear associations where blood lead decline was 0.1 μg/dL or higher. Declines in blood lead were nonsignificantly associated with declines in diastolic blood pressure and significantly associated with declines in interventricular septum thickness.

CONCLUSIONS

Declines in blood lead levels in American Indian adults, even when small (0.1-1.0 μg/dL), were associated with reductions in systolic blood pressure. These findings suggest the need to further study the cardiovascular impacts of reducing lead exposures and the importance of lead exposure prevention.

Comparison of circulating and excreted metals and of autoimmunity between two Great Plains Tribal communities

Metals contaminants of the environment from mine waste have been implicated as contributing agents in autoimmune disease. The current study compares metals and autoimmunity in two Tribal communities residing in the Black Hills and the Bighorn Mountains geographical regions that are scattered with extant hard rock mines. With documented drinking water contamination in both communities, in vivo levels of more than half of the measured serum and urine metals differed between the two communities and were substantially different from their national median values. Serum autoantibodies associated with systemic autoimmune disease were rare or at low-level, but antibodies to denatured (single-stranded) DNA and thyroid-specific autoantibodies were commonly elevated, especially in women. A three-tier statistical modeling process was carried out to examine individual metals exposure as predictors of autoantibody levels. For the most part only weak positive associations between individual metals and systemic autoantibodies were found, although univariate quantile regression analysis showed positive statistical associations of serum lead and antimony with anti-chromatin and anti-histone autoantibodies. Using age and gender-adjusted multivariable statistical models, metals did not predict anti-thyroglobulin or -thyroid peroxidase significantly and metals were generally negative predictors of the other autoantibodies. Overall these results suggest that elevated levels of environmental metals and metalloids in these communities may result in suppression of autoantibodies associated with systemic autoimmune disease.

Feasibility and Acceptability of Using Ecological Momentary Assessment to Evaluate Alcohol Use with American Indian Women

BACKGROUND

Ecological momentary assessments (EMA) are one way to collect timely and accurate alcohol use data, as they involve signaling participants via cell phones to report on daily behaviors in real-time and in a participant's natural environment. EMA has never been used with American Indian populations to evaluate alcohol consumption. The purpose of this project was to determine the feasibility and acceptability of EMA for American Indian women.

METHODS

Eligible participants were American Indian women between the ages of 18 and 44 who were not pregnant and had consumed more than one drink within the past month. All participants received a TracFone and weekly automated messages. Self-reported measures of daily quantity and frequency of alcohol consumption, alcohol type, and context were assessed once per week for four weeks. Baseline measurements also included the Drinking Motives Questionnaire-Revised (DMQ-R) and the Interpersonal Support Evaluation List (ISEL).

RESULTS

Fifteen participants were enrolled in the study. All but one participant completed all data collection time points, and drinking patterns were consistent across the study period. A total of 420 records were completed across 86 drinking days and 334 non-drinking days. Participants reported drinking an average of 5.7 days over the 30-day period and typically consumed 3.99 drinks per drinking occasion. Sixty-six percent of participants met gender-specific cut-points for heavy episodic drinking, with an average of 2.46 binge drinking occasions across the four week study period.

CONCLUSIONS

This proof-of-concept project showed that EMA was both feasible and acceptable for collecting alcohol data from American Indian women. Additional studies are necessary to fully implement EMA with American Indian women to better understand the drinking motives, contexts, patterns, and risk factors in this population.

Behavioral determinants of arsenic-safe water use among Great Plains Indian Nation private well users: results from the Community-Led Strong Heart Water Study Arsenic Mitigation Program

BACKGROUND

The objective of this study was to evaluate the behavioral determinants associated with exclusive use of arsenic-safe water in the community-led Strong Heart Water Study (SHWS) arsenic mitigation program.

METHODS

The SHWS is a randomized controlled trial of a community-led arsenic mitigation program designed to reduce arsenic exposure among private well users in American Indian Great Plains communities. All households received point-of-use (POU) arsenic filters installed at baseline and were followed for 2 years. Behavioral determinants selected were those targeted during the development of the SHWS program, and were assessed at baseline and follow-up.

RESULTS

Among participants, exclusive use of arsenic-safe water for drinking and cooking at follow-up was associated with higher self-efficacy for accessing local resources to learn about arsenic (OR: 5.19, 95% CI: 1.48-18.21) and higher self-efficacy to resolve challenges related to arsenic in water using local resources (OR: 3.11, 95% CI: 1.11-8.71). Higher commitment to use the POU arsenic filter faucet at baseline was also a significant predictor of exclusive arsenic-safe water use for drinking (OR: 32.57, 95% CI: 1.42-746.70) and cooking (OR: 15.90, 95% CI: 1.33-189.52) at follow-up. From baseline to follow-up, the SHWS program significantly increased perceived vulnerability to arsenic exposure, self-efficacy, descriptive norms, and injunctive norms. Changing one's arsenic filter cartridge after installation was associated with higher self-efficacy to obtain arsenic-safe water for drinking (OR: 6.22, 95% CI: 1.33-29.07) and cooking (OR: 10.65, 95% CI: 2.48-45.68) and higher perceived vulnerability of personal health effects (OR: 7.79, 95% CI: 1.17-51.98) from drinking arsenic-unsafe water.

CONCLUSIONS

The community-led SHWS program conducted a theory-driven approach for intervention development and evaluation that allowed for behavioral determinants to be identified that were associated with the use of arsenic safe water and changing one's arsenic filter cartridge. These results demonstrate that theory-driven, context-specific formative research can influence behavior change interventions to reduce water arsenic exposure. The SHWS can serve as a model for the design of theory-driven intervention approaches that engage communities to reduce arsenic exposure.

TRIAL REGISTRATION

The SHWS is registered with ClinicalTrials.gov (Identifier: NCT03725592).

Evaluation of a water arsenic filter in a participatory intervention to reduce arsenic exposure in American Indian communities: The Strong Heart Water Study

Many rural populations, including American Indian communities, that use private wells from groundwater for their source of drinking and cooking water are disproportionately exposed to elevated levels of arsenic. However, programs aimed at reducing arsenic in American Indian communities are limited. The Strong Heart Water Study (SHWS) is a randomized controlled trial aimed at reducing arsenic exposure among private well users in American Indian Northern Great Plains communities. The community-led SHWS program installed point-of-use (POU) arsenic filters in the kitchen sink of households, and health promoters delivered arsenic health communication programs. In this study we evaluated the efficacy of these POU arsenic filters in removing arsenic during the two-year installation period. Participants were randomized into two arms. In the first arm households received a POU arsenic filter, and 3 calls promoting filter use (SHWS mobile health (mHealth) & filter arm). The second arm received the same filter and phone calls, and 3 in-person home visits and 3 Facebook messages (SHWS intensive arm) for program delivery. Temporal variability in water arsenic concentrations from the main kitchen faucet was also evaluated. A total of 283 water samples were collected from 50 households with private wells from groundwater (139 filter and 144 kitchen faucet samples). Ninety-three percent of households followed after baseline had filter faucet water arsenic concentrations below the arsenic maximum contaminant level of 10 μg/L at the final visit during our 2 year study period with no difference between study arms (98 % in the intensive arm vs. 94 % in the mHealth & filter arm). No significant temporal variation in kitchen arsenic concentration was observed over the study period (intraclass correlation coefficient = 0.99). This study demonstrates that POU arsenic filters installed for the community participatory SHWS program were effective in reducing water arsenic concentration in study households in both arms, even with delivery of the POU arsenic filter and mHealth program only. Furthermore, we observed limited temporal variability of water arsenic concentrations from kitchen faucet samples collected over time from private wells in our study setting.

Return of Participants' Incidental Genetic Research Findings: Experience from a Case-Control Study of Asthma in an American Indian Community

PURPOSE

The proper communication of clinically actionable findings to participants of genetic research entails important ethical considerations, but has been challenging for a variety of reasons. We document an instance of return of individual genetic results in the context of a very rural American Indian community, in hopes of providing insight to other investigators about potentially superior or inferior courses of action.

METHODS

The original study was a case/control study of asthma among 324 pediatric participants. The study utilized a genotyping microarray assessing over 2 million variants, including one conferring risk for hypertrophic cardiomyopathy for which the American College of Medical Genetics recommends return of results to participants. The study investigators engaged in extensive consultation with the IRB, the Tribal government and local clinicians to better inform our approach.

RESULTS

With some difficulty we were able to notify the 2 participants heterozygous for this variant. One participant welcomed this information and proceeded to obtain further clinical work-up; the other participant declined further follow-up.

CONCLUSION

While demanding of considerable time and effort, the return of clinically actionable genetic results is important from both an ethical perspective and to provide an improved trust relationship with the community of research participants.

Blood cadmium, lead, manganese, mercury, and selenium levels in American Indian populations: The Strong Heart Study

BACKGROUND

Many American Indian (AI) communities are in areas affected by environmental contamination, such as toxic metals. However, studies assessing exposures in AI communities are limited. We measured blood metals in AI communities to assess historical exposure and identify participant characteristics associated with these levels in the Strong Heart Study (SHS) cohort.

METHOD

Archived blood specimens collected from participants (n = 2014, all participants were 50 years of age and older) in Arizona, Oklahoma, and North and South Dakota during SHS Phase-III (1998-1999) were analyzed for cadmium, lead, manganese, mercury, and selenium using inductively coupled plasma triple quadrupole mass spectrometry. We conducted descriptive analyses for the entire cohort and stratified by selected subgroups, including selected demographics, health behaviors, income, waist circumference, and body mass index. Bivariate associations were conducted to examine associations between blood metal levels and selected socio-demographic and behavioral covariates. Finally, multivariate regression models were used to assess the best model fit that predicted blood metal levels.

FINDINGS

All elements were detected in 100% of study participants, with the exception of mercury (detected in 73% of participants). The SHS population had higher levels of blood cadmium and manganese than the general U.S. population 50 years and older. The median blood mercury in the SHS cohort was at about 30% of the U.S. reference population, potentially due to low fish consumption. Participants in North Dakota and South Dakota had the highest blood cadmium, lead, manganese, and selenium, and the lowest total mercury levels, even after adjusting for covariates. In addition, each of the blood metals was associated with selected demographic, behavioral, income, and/or weight-related factors in multivariate models. These findings will help guide the tribes to develop education, outreach, and strategies to reduce harmful exposures and increase beneficial nutrient intake in these AI communities.

Diet Quality and Depression in a Cohort of American Indians: The Strong Heart Family Study

Diet quality has been shown to be inversely associated with depression, but this has not been studied in American Indians (AIs). We examined the prospective association of diet quality and probable depression in a family-based cohort of rural AIs. Using data from the Strong Heart Family Study, we included 1,100 AIs ≥14 years old who were free of probable depression at baseline. We defined probable depression as the presence of moderate or severe depressive symptoms on the Center for Epidemiologic Studies Depression Scale or current use of antidepressant medications. We calculated baseline diet quality from food frequency questionnaires using the Alternative Healthy Eating Index-2010 (AHEI). We used GEE-based multivariate logistic regression to estimate the odds ratio of probable depression at follow up associated with a 10-point higher AHEI score at baseline, adjusted for demographic, psychosocial, and health factors. At follow up, 19% (n = 207) of the sample reported probable depression. Diet quality was not associated with report of probable depression at follow up (OR = 1.16, 95% CI [0.96, 1.39]). Research is needed to examine other temporal dimensions of this relationship and unique aspects of rural AI diets and psychosocial factors that may influence depression.

Adaptations of an RCT during COVID: Case Study in one Rural American Indian Community

The COVID-19 pandemic is global in nature but especially threatens American Indian and Alaska Native (AI/AN) communities due to pre-existing conditions and social determinants of health. Because of the higher risk to AI/AN communities, many tribal nations have been proactive in their policies to keep the virus at bay, including travel restrictions and lockdowns. This affected tribal programs as well as collaborative research projects. One project impacted is the Native CHOICES project, an ongoing randomized controlled trial with an AI/AN community that is focused on the prevention of alcohol-exposed pregnancies. Originally designed to be conducted via in-person motivational interviewing sessions, COVID-19 restrictions precluded the intervention from being delivered in-person as it was designed. The study team received valuable input from the project’s Community Advisory Board (CAB) and community-based staff to establish a feasible and acceptable way of conducting the intervention while respecting tribally-enacted COVID-19 restrictions. The goal of this brief report is to outline not just the process to adapting to COVID-19 but also to provide recommendations for future public health programs, including the ongoing need to consider gaps in access affecting resource-poor settings.

Spatial relationship between well water arsenic and uranium in Northern Plains native lands

Arsenic and uranium in unregulated private wells affect many rural populations across the US. The distribution of these contaminants in the private wells of most American Indian communities is poorly characterized, and seldom studied together. Here, we evaluate the association between drinking water arsenic and uranium levels in wells (n = 441) from three tribal regions in North Dakota and South Dakota participating in the Strong Heart Water Study. Groundwater contamination was extensive; 29% and 7% of wells exceeded maximum contaminant levels for arsenic and uranium respectively. 81% of wells had both arsenic and uranium concentrations at one-tenth of their human-health benchmark (arsenic, 1 μg/L; uranium 3 μg/L). Well arsenic and uranium concentrations were uncorrelated (rs = 0.06); however, there appeared to be a spatial correlation of wells co-contaminated by arsenic and uranium associated with flow along a geologic contact. These findings indicate the importance of measuring multiple metals in well water, and to understand underlying hydrogeological conditions. The underlying mechanisms for the prevalence of arsenic and uranium across Northern Plains Tribal Lands in the US, and in particular the occurrence of both elevated arsenic and uranium in drinking water wells in this region, demands further study.

Cooking for Health: a healthy food budgeting, purchasing, and cooking skills randomized controlled trial to improve diet among American Indians with type 2 diabetes

Background

The prevalence of poor diet quality and type 2 diabetes are exceedingly high in many rural American Indian (AI) communities. Because of limited resources and infrastructure in some communities, implementation of interventions to promote a healthy diet is challenging—which may exacerbate health disparities by region (urban/rural) and ethnicity (AIs/other populations). It is critical to adapt existing evidence-based healthy food budgeting, purchasing, and cooking programs to be relevant to underserved populations with a high burden of diabetes and related complications. The Cooking for Health Study will work in partnership with an AI community in South Dakota to develop a culturally-adapted 12-month distance-learning-based healthy food budgeting, purchasing, and cooking intervention to improve diet among AI adults with type 2 diabetes.

Methods

The study will enroll 165 AIs with physician-diagnosed type 2 diabetes who reside on the reservation. Participants will be randomized to an intervention or control arm. The intervention arm will receive a 12-month distance-learning curriculum adapted from Cooking Matters® that focuses on healthy food budgeting, purchasing, and cooking skills. In-person assessments at baseline, month 6 and month 12 will include completion of the Nutrition Assessment Shared Resources Food Frequency Questionnaire and a survey to assess frequency of healthy and unhealthy food purchases. Primary outcomes of interest are: (1) change in self-reported intake of sugar-sweetened beverages (SSBs); and (2) change in the frequency of healthy and unhealthy food purchases. Secondary outcomes include: (1) change in self-reported food budgeting skills; (2) change in self-reported cooking skills; and (3) a mixed-methods process evaluation to assess intervention reach, fidelity, satisfaction, and dose delivered/received.

Discussion

Targeted and sustainable interventions are needed to promote optimal health in rural AI communities. If effective, this intervention will reduce intake of SSBs and the purchase of unhealthy foods; increase the purchase of healthy foods; and improve healthy food budgeting and cooking skills among AIs with type 2 diabetes – a population at high risk of poor health outcomes. This work will help inform future health promotion efforts in resource-limited settings.

Trial registration

This study was registered on ClinicalTrials.gov on October 9, 2018 with Identifier NCT03699709.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10308-8.

Whole Genome Sequence of Xylella fastidiosa ATCC 35879T and Detection of Genome Rearrangements Within Subsp. fastidiosa

Xylella fastidiosa is a Gram-negative and nutritionally fastidious bacterial pathogen causing Pierce's disease (PD) of grapevine and other plant diseases. X. fastidiosa strain ATCC 35879^T which originated from Florida is the designated type strain for the species and for subsp. fastidiosa. In bacterial taxonomy, type strains preserve the characters of the original descriptions. Whole genome sequence of a type strain not only provides a standard reference for bacterial taxonomy, but also facilitates research in other fields such as population diversity and genome evolution. In this study, the whole genome sequence of strain ATCC 35879^T was determined using PacBio RSII format. The ATCC 35879^T genome has a circular chromosome of 2,565,504 bp with 2,904 predicted protein coding genes and 55 RNA genes, and a circular plasmid of 41,753 bp. The chromosomal sequence of strain ATCC 35879^T was compared to that of X. fastidosa subsp. fastidiosa strain M23 from California which causes both PD and almond leaf scorch disease. Genome rearrangements involving a ~ 1,200 K bp region were detected. Genome annotations showed clusters of phage-related genes around the rearrangement junctions, suggesting the likely involvement of phage activities. This is the first report on genome structure variations within strains of X. fastidiosa subsp. fastidiosa.

Dietary determinants of inorganic arsenic exposure in the Strong Heart Family Study

BACKGROUND

Chronic exposure to inorganic arsenic (iAs) in the US occurs mainly through drinking water and diet. Although American Indian (AI) populations have elevated urinary arsenic concentrations compared to the general US population, dietary sources of arsenic exposure in AI populations are not well characterized.

METHODS

We evaluated food frequency questionnaires to determine the major dietary sources of urinary arsenic concentrations (measured as the sum of arsenite, arsenate, monomethylarsonate, and dimethylarsinate, ΣAs) for 1727 AI participants in the Strong Heart Family Study (SHFS). We compared geometric mean ratios (GMRs) of urinary ΣAs for an interquartile range (IQR) increase in reported food group consumption. Exploratory analyses were stratified by gender and study center.

RESULTS

In fully adjusted generalized estimating equation models, the percent increase (95% confidence interval) of urinary ΣAs per increase in reported food consumption corresponding to the IQR was 13% (5%, 21%) for organ meat, 8% (4%, 13%) for rice, 7% (2%, 13%) for processed meat, and 4% (1%, 7%) for non-alcoholic drinks. In analyses stratified by study center, the association with organ meat was only observed in North/South Dakota. Consumption of red meat [percent increase -7% (-11%, -3%)] and fries and chips [-6% (-10%, -2%)] was inversely associated with urinary ΣAs.

CONCLUSIONS

Organ meat, processed meat, rice, and non-alcoholic drinks contribute to ΣAs exposure in the SHFS population. Organ meat is a unique source of ΣAs exposure for North and South Dakota participants and may reflect local food consumption. Further studies should comprehensively evaluate drinking water arsenic in SHFS communities and determine the relative contribution of diet and drinking water to total arsenic exposure.

Active smoking, secondhand smoke exposure and serum cotinine levels among Cheyenne River Sioux communities in context of a Tribal Public Health Policy

INTRODUCTION

American Indians and Alaska Natives face disproportionately high rates of smoking and secondhand smoke (SHS) exposure. The Cheyenne River Sioux Tribe (CRST) is among the few Tribal Nations controlling commercial tobacco exposures in public and work places. We had an opportunity to explore effects of the new commercial tobacco-free policy (implemented in 2015) in an environmental health study (2014-2016) that collected information about commercial tobacco use and SHS prevalence and examined predictor variables of serum cotinine concentrations.

METHODS

Self-reported survey data were used in quantile regression statistical modelling to explore changes in cotinine levels, based on smoking status, smokeless tobacco consumption and SHS exposure.

RESULTS

From enrolled 225 adults, 51% (N=114) were current smokers. Among 88 non-tobacco users, 35 (40%) reported current SHS exposure. Significant differences in cotinine median concentrations were found among participants with and without current SHS exposure. Extremely high cotinine concentrations (~100 times larger than the median) were detected in some non-tobacco users. After implementing the new smoke-free air Tribal policy, cotinine decreased in participants with intermediate (3-15 ng/mL, non-tobacco users with SHS exposure) and high (>15 ng/mL, mainly tobacco users) cotinine levels showing association with an abatement of opportunities for SHS exposure. Significant predictors of cotinine levels were sampling year, current smoking and tobacco chewing. No gender differences were observed in cotinine.

CONCLUSIONS

Our results show decrease in cotinine concentrations in CRST participants since implementation of their 'Smoke-Free Clean Air Act' in 2015.

The Strong Heart Water Study: Informing and designing a multi-level intervention to reduce arsenic exposure among private well users in Great Plains Indian Nations

Elevated arsenic exposure from drinking water is associated with an increased risk of cardiovascular disease, diabetes, kidney disease, and skin, lung, and bladder cancer. Arsenic contamination in groundwater supplies disproportionately affects rural populations using private wells. Arsenic mitigation programs for American Indian communities are limited. There is an urgent need for targeted approaches to reduce arsenic exposure for at-risk communities using private wells. Formative research was conducted to inform and design a community-based arsenic mitigation intervention for Lakota and Dakota Nations in the Great Plains Area of the United States, where, in some communities, one-quarter of private wells are estimated to have elevated arsenic. Formative research included semi-structured interviews, a community workshop, intervention-planning workshops, and a pilot study of the developed intervention. Community members prioritize aesthetic qualities of water (e.g. taste, color), safety, and other situational factors (e.g. cost) when considering their drinking and cooking water. Although water safety is a concern, awareness and concern for arsenic vary substantially within communities. To reduce arsenic exposure, community members recommended communication of water test results, home visits for intervention delivery, and reminders to use arsenic-safe water. Findings informed the development of an intervention to prevent arsenic exposure through drinking water and cooking, including health promotion messages and household items to facilitate use of an arsenic removal device (e.g. tankards to store filtered water). The pilot study indicated promising acceptability and operability of the developed intervention. This research provides a model for the development of environmental health interventions in partnership with American Indian and other private well-using communities.

Arsenic in groundwater in private wells in rural North Dakota and South Dakota: Water quality assessment for an intervention trial

Elevated exposure to arsenic disproportionately affects populations relying on private well water in the United States (US). This includes many American Indian (AI) communities where naturally occurring arsenic is often above 10 µg/L, the current US Environmental Protection Agency safety standard. The Strong Heart Water Study is a randomized controlled trial aiming to reduce arsenic exposure to private well water users in AI communities in North Dakota and South Dakota. In preparation for this intervention, 371 households were included in a community water arsenic testing program to identify households with arsenic ≥10 µg/L by inductively coupled plasma mass spectrometry (ICP-MS). Arsenic ≥10 µg/L was found in 97/371 (26.1%) households; median water arsenic concentration was 6.3 µg/L, ranging from <1-198 µg/L. Silica was identified as a water quality parameter that could impact the efficacy of arsenic removal devices to be installed. A low-range field rapid arsenic testing kit evaluated in a small number of households was found to have low accuracy; therefore, not an option for the screening of affected households in this setting. In a pilot study of the effectiveness of a point-of-use adsorptive media water filtration device for arsenic removal, all devices installed removed arsenic below 1 µg/L at both installation and 9 months post-installation. This study identified a relatively high burden of arsenic in AI study communities as well as an effective water filtration device to reduce arsenic in these communities. The long-term efficacy of a community based arsenic mitigation program in reducing arsenic exposure and preventing arsenic related disease is being tested as part of the Strong Heart Water Study.

Availability and Cost of Healthy Foods in a Large American Indian Community in the North-Central United States

To understand the local food environment in a rural American Indian community, we assessed the availability and price of healthy foods offered at all stores (n = 27) within a 90-mile radius of the town center of a large American Indian reservation. Stores were classified by type, and availability and cost of foods were measured using the Nutrition Environment Measures Survey in Stores (January–February 2016). Healthy foods were available at most grocery stores (>97%), although the price of foods varied considerably among stores. Having quantified the availability and cost of food, efforts must focus on understanding other structural and contextual factors that influence diet in this community.

Time-to-Treatment for Myocardial Infarction: Barriers and Facilitators Perceived by American Indians in Three Regions

Early recognition of acute myocardial infarction (MI), followed by prompt emergency care, improves patient outcomes. Among rural American Indian (AI) populations there are disparities in access to care for MI and processes of care, resulting in poor MI-related health outcomes compared to the general population. We sought to gain an understanding of barriers related to MI time-to-treatment delays using a qualitative approach. We conducted semi-structured interviews and focus groups with AI key informants and community members in three Indian Health Service regions. Major barriers to care included long travel distance to care and lack of supporting infrastructure; distrust of the health care system; low overall literacy and basic health literacy; priority of family care-giving; and lack of specialized medical facilities and specialists. Findings suggest that improved time-to-treatment facilitators include educating the local community about the causes and consequences of MI and culturally-sensitive health communication, as well as addressing the quality of local systems of care and the community's perception of these systems. Pursuing these strategies may improve quality of care and reduce MI-related morbidity and mortality in rural AI populations.

Cranial Magnetic Resonance Imaging in Elderly American Indians: Design, Methods, and Implementation of the Cerebrovascular Disease and Its Consequences in American Indians Study

The Cerebrovascular Disease and its Consequences in American Indians (CDCAI) Study recruited surviving members of a 20-year, longitudinal, population-based cohort of American Indians focused on cardiovascular disease, its risk factors, and its consequences. The goal of the CDCAI Study is to characterize the burden, risk factors, and manifestations of vascular brain injury identified on cranial MRI. The CDCAI Study investigators enrolled 1,033 participants aged 60 and older from 11 American Indian communities and tribes in the Northern Plains, Southern Plains, and Southwestern United States. In addition to cranial MRI performed according to standardized protocols, participants underwent extensive medical interview, clinical examination, neurocognitive testing, physical function evaluation, electrocardiogram, and provided blood and urine specimens. Participants also self-administered questionnaires covering demographics, quality of life, and medical history. This report describes the design, implementation, and some of the unique challenges of this study and data collection.

Prevalence of sexually transmitted diseases and human immunodeficiency virus among women attending prenatal services in Apia, Samoa

There is no routine prenatal screening for sexually transmitted diseases (STDs) and human immunodeficiency virus (HIV) in pregnancy in Samoa. Testing for chlamydial infection is not available. To gather information on pregnant women, a prevalence survey was conducted in Apia, Samoa, utilizing two prenatal hospital clinics. Pregnant ( n = 427) women were tested for Neisseria gonorrhoeae, Chlamydia trachomatis and Trichomonas vaginalis using polymerase chain reaction (PCR), and for syphilis ( n = 441) by rapid plasmid reagin (RPR) and HIV ( n = 441) by enzyme-linked immunosorbent assay (ELISA). Results were: chlamydia 30.9% (132); trichomoniasis 20.8%; gonorrhoea 3.3%; syphilis 0.5%; and HIV 0%. Overall 42.7% had at least 1 STD. Young women aged <25 years were three times more likely to have a STD than older women (odds ratio = 3.0, 95% confidence intervals 2.0, 4.5). The lack of inexpensive, reliable field diagnostics remain a barrier to sustainable STD control programmes for pregnant women living in developing countries.

Pharmacokinetics and pharmacodynamics of the myotoxic venom of Pseudechis australis (mulga snake) in the anesthetised rat

CONTEXT

Myotoxicity is a common clinical effect of snake envenoming and results from either local or systemic myotoxins in snake venoms. Although numerous myotoxins have been isolated from snake venoms, there has been limited study on the relationship between the time course of venom concentrations (pharmacokinetics) and the time course of muscle injury measured as a rise in creatine kinase (CK) (pharmacodynamics).

OBJECTIVE

The aim of this study was to develop an in vivo model of myotoxicity to investigate the time course of myotoxicity and the effect of antivenom.

MATERIALS AND METHODS

Anesthetised rats were administered Pseudechis australis (mulga snake) venom either through i.v., i.m. or s.d. route, including a range of doses (5-100 μg/kg). Serial blood samples were collected for measurement of venom using enzyme immunoassay and measurement of CK and creatinine. Antivenom was administered before, 1 and 6 h after venom administration to investigate its effect on muscle injury. Plots of venom and CK versus time were made and the area under the curve (AUC) was calculated.

RESULTS

There was a significant dose-dependent increase in CK concentration after administration of P. australis venom, which was greatest for i.v. administration. Timed measurement of venom concentrations showed a rapid absorption through s.d. and i.m. routes and a delayed rise in CK concentrations following any route. Antivenom prevented myotoxicity shown by a decrease in the CK AUC, which was most effective if given earliest. There was a rise in creatinine following i.v. venom administration.

CONCLUSION

The study shows the delayed relationship between venom absorption and the rise in CK, consistent with the delayed onset of myotoxicity in human envenoming. Antivenom prevented myotoxicity more effectively if given earlier.

Recurrent femoral hernia and associated ovarian pathology

The following case describes an ovarian tumour presenting in a highly unusual manner-in the form of a recurrent femoral hernia. Recurrent femoral herniae are unusual and should prompt awareness of underlying pathology causing increased intra-abdominal pressure.

Haemolytic uraemic syndrome associated with interfamilial spread of E. coli O26:H11

In September 2000, haemolytic uraemic syndrome (HUS) was diagnosed in a 10-month-old child with a prodromal history of vomiting and diarrhoea (non-bloody). Investigation revealed that a self-limiting gastrointestinal illness (mean duration 48 h) had occurred among immediate and extended family in the 2 weeks prior to the child's admission. The epidemiology of the illness suggested person-to-person spread. Five children (close family contacts) had E. coli O26 verocytotoxin (VT1 and VT2) isolated from stools. Stool culture and serology from the index case were negative for shiga toxin-producing E. coli (STEC) organisms. Control measures in accordance with the Public Health Laboratory Service (PHLS), verocytotoxogenic organisms (VTEC) guidelines were applied to prevent further spread among the extended family and contacts. Despite detailed food and environmental exposure histories, the source of the illness was not identified. This incident highlights the importance of investigation of cases of post-diarrhoeal HUS, for potential shiga toxin E. coli aetiology.

Cervical screening history in patients with early stage carcinoma of the cervix

This study aimed to examine whether a decade of heightened publicity on issues relating to cervical screening has changed the screening profile of women presenting with cervical cancer at the National Maternity Hospital. The screening history of 100 women diagnosed with early/surgically treated cervical cancer between 1998 and 2002 was compared with a similar study conducted in 1982 /1990. The percentage of women never screened was similar - 24 %( 2002) and 23% (1990). The interval between last recorded smear and diagnosis of disease was greater than 5 years in 45.6% and 41.7% respectively. Overall 60% of women in the recent period had either failed to avail of screening or were not screened within 5 years of diagnosis compared with 64% in 1990. Multiparous women comprised 90% of the study group and 50% of those inadequately screened were attending their general practitioner on a regular basis - therefore affording a potential for opportunistic screening The current method of screening has failed in this group and has not improved in 10 years despite of increased population awareness and greater opportunities for screening than ever before and would support an argument for a National Screening Program.

A phase I clinical and pharmacokinetic study of the multi-drug resistance protein-1 (MRP-1) inhibitor sulindac, in combination with epirubicin in patients with advanced cancer

PURPOSE

Multi-drug resistance mediated by ATP-binding cassette trans-membrane protein pumps is an important cause of cancer treatment failure. Sulindac has been shown to be a competitive substrate for the clinically important resistance protein, multi-drug resistance protein-1 (MRP-1), and thus might enhance the anti-cancer activity of substrate chemotherapeutic agents, e.g. anthracyclines.

METHODS

We conducted a dose-escalating, single arm, prospective, open label, non-randomised phase I trial of epirubicin (75 mg/m(2)) in combination with escalating oral doses of sulindac (0-800 mg) in patients with advanced cancer to identify an appropriate dose of sulindac to use in future resistance studies. Anthracycline and sulindac pharmacokinetics were studied in cycles 1 and 3.

RESULTS

Seventeen patients (8 breast, 3 lung, 2 bowel, 1 melanoma, 1 renal, 1 ovarian and 1 of unknown primary origin, 16/17 having had prior chemotherapy) were enrolled. Eight patients received a full six cycles of treatment; 14 patients received three or more cycles. Dose-limiting toxicity was observed in two patients at 800 mg sulindac (1 renal impairment, 1 fatal haemoptysis in a patient with advanced lung cancer), and sulindac 600 mg was deemed to be the maximum tolerated dose. Sulindac had no effect on epirubicin pharmacokinetics. Among 15 patients with evaluable tumour, two partial responses were seen (malignant melanoma and breast cancer). Four others had prolonged stable disease.

CONCLUSION

Epirubicin 75 mg/m(2) and sulindac 600 mg are the recommended doses for phase II studies for these agents in combination.

Risk factors for disease progression in patients with lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH): a systematic analysis of expert opinion

Disease progression has become an important issue for the management of lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH). Although several risk factors have been identified, no specific patient risk profiles have been established that can be useful in the day-to-day management of LUTS/BPH. In this study, an international panel of urologists developed a risk classification based on the attribution of a risk score to 243 unique patient profiles. From the perspective of clinical decision making, it was concluded that postvoid residual, symptom severity and maximum flow rate are the most relevant determinants of the risk of disease progression.

Tonsillectomy--cold dissection vs. hot dissection: a prospective study

Throughout the years, investigators and surgeons have developed new techniques for tonsillectomy aiming to lessen the postoperative morbidity and complications of tonsillectomy. It is generally accepted that the ideal method should decrease operative time, blood loss, postoperative haemorrhage and morbidity. To compare the technique and post-operative morbidity of two different tonsillectomy methods: cold dissection and bipolar electrodissection. A prospective study including a total of 545 children (Age: 3-16 yrs) undergoing tonsillectomy at The Children's University Hospital in Dublin, Ireland, from January 2003 to December 2003. The incidence of primary, secondary haemorrhage and postoperative pain was compared between both techniques. The overall rate of haemorrhage was 3.6% (20 patients) this included primary haemorrhage in 0.3% (2 patients) and secondary haemorrhage in 3.3% (18 patents). Primary haemorrhage occurred only in the electrodissection technique. As regards to secondary haemorrhage it was higher in the electrodissection technique 2.3% (12 patients) compared to 1% (6 patients) of the cold dissection technique. Patients rated pain to be more severe in the electrodissection technique compared to the cold dissection technique. Cold dissection tonsillectomy technique is still considered to be a safe and effective method with less posoperative morbidity complications as evidenced from our study.

Integrating risk profiles for disease progression in the treatment choice for patients with lower urinary tract symptoms/benign prostatic hyperplasia: a combined analysis of external evidence and clinical expertise

The RAND appropriateness method was used to explore the relevance of risk factors for disease progression in the treatment choice for patients with lower urinary tract symptoms/benign prostatic hyperplasia (LUTS/BPH). A total of, 12 international experts assessed the appropriateness of various treatments for 243 risk profiles. Highest appropriateness rates were found for alpha1-adrenoceptor antagonists (68% of profiles) and combination therapy (46%). A large prostate volume was the dominant argument in favour of 5alpha-reductase inhibitors and combination therapy, but was irrelevant for the choice of surgery. Considerable postvoid residual, severe symptoms and poor maximum flow rate were the most important factors in favour of surgery.

Guidelines for the management of hepatitis C in general practice: a semi-qualitative interview survey of GPs’ views regarding content and implementation

BACKGROUND

Hepatitis C is a common infection among people who attend GPs for methadone maintenance treatment.

AIM

To determine the views of GPs towards clinical guidelines for the management of hepatitis C among current or former injecting drug users in advance of their implementation.

METHODS

A purposive sample of 14 GPs (10% of the total prescribing methadone at the time the guidelines were developed) was invited to review a pre-publication draft of the guidelines and interviewed regarding content, presentation, perceived barriers to implementation and suggested interventions to facilitate effective implementation of the guidelines.

RESULTS

GPs indicated the guidelines were useful but suggested aspects of presentation should be clarified. Organisational issues were identified as the principal barriers to effective implementation, with the provision of additional nursing support the principal intervention suggested to facilitate implementation.

CONCLUSIONS

Interviewing intended recipients may be an important step in ensuring clinical practice guidelines are effectively implemented.

Folic acid supplements to prevent neural tube defects: trends in East of Ireland 1996-2002

Promotion of folic acid to prevent neural Tube Defects (NTD) has been ongoing for ten years in Ireland, without a concomitant reduction in the total birth prevalence of NTD. The effectiveness of folic acid promotion as the sole means of primary prevention of NTD is therefore questionable. We examined trends in folic acid knowledge and peri-conceptional use from 1996-2002 with the aim of assessing the value of this approach. From 1996-2002, 300 women attending ante-natal clinics in Dublin hospitals annually were surveyed regarding their knowledge and use of folic acid. During the period the proportion who had heard of folic acid rose from 54% to 94% between 1996 and 2002 (c2 test for trend: p<0.001). Knowledge that folic acid can prevent NTD also rose from 21% to 66% (c2 test for trend: p<0.001). Although the proportion who took folic acid during pregnancy increased from 14% to 83% from 1996 to 2002 (c2 test for trend: p<0.001), peri-conceptional intake did not rise above 24% in any year. There is a high awareness of folic acid and its relation to NTD, which is not matched by peri-conceptional uptake. The main barrier to peri-conceptional uptake is the lack of pregnancy planning. To date promotional campaigns appear to have been ineffective in reducing the prevalence of NTD in Ireland. Consequently, fortification of staple foodstuffs is the only practical and reliable means of primary prevention of NTD.

The North Dublin randomized controlled trial of structured diabetes shared care

BACKGROUND

A new diabetes shared care service was introduced in North Dublin. It was designed as a randomized controlled trial with a complex intervention comprising education of participating practitioners, the introduction of a community-based diabetes nurse specialist, local agreement on clinical protocols and structured communication across the primary-secondary care interface.

OBJECTIVES

Our aim was to assess the feasibility and effectiveness of a structured diabetes shared care service in a mixed health care system and to analyse the impact on total patient care.

METHODS

A Cluster randomized controlled trial lasting 18 months was carried out in 183 patients with type 2 diabetes from 30 general practices in North Dublin. Biophysical outcomes (HbA1c, blood pressure, body mass index), psychosocial measures (smoking status and Diabetes Clinic Treatment Satisfaction and Diabetes Well-being scores) and process outcomes were collected.

RESULTS

There were significant improvements in diabetes care delivery and in psychosocial outcomes, but no significant improvements in biomedical outcomes. Process data collection revealed a significant increase in diabetes care-related activity for participating patients with an increase in structured annual reviews and fewer patients defaulting from care. There were also significant improvements in information exchange between primary and secondary care.

CONCLUSION

Structured diabetes shared care, in a mixed health care system, can produce significant improvements in diabetes care delivery and in psychosocial outcomes for patients, with improved information exchange across the primary-secondary care interface.

A qualitative investigation of the views and health beliefs of patients with Type 2 diabetes following the introduction of a diabetes shared care service

AIMS

A qualitative research approach was adopted in order to explore the views and health beliefs of patients with Type 2 diabetes who had experienced a new structured diabetes shared care service.

METHODS

Patients from 15 general practices were randomly selected and invited to attend three focus groups. Two independent researchers adopted the "Framework" technique to analyse the transcribed data and identify key themes expressed by patients.

RESULTS

Themes relating to diabetes included frustration, victimization and powerlessness in relation to living with diabetes, controlling blood sugar, medication and economic barriers to care. Differences in emphases between patients and healthcare providers emerged. Patients were generally positive about shared care and largely identified it with the nurses involved.

CONCLUSION

This research highlights the importance of an in-depth exploration of patients' views during changes in diabetes care delivery to identify service delivery failures and gaps in patient knowledge such as lack of awareness of the extent of macrovascular risk.

Does neostigmine increase gastric emptying in the critically ill?--results of a pilot study

OBJECTIVE

Based on the successful use of neostigmine for the treatment of acute colonic pseudo-obstruction, we hypothesised that neostigmine would increase gastric emptying and improve tolerance to enteral feeding in the critically ill patient.

METHODS

Eleven patients intolerant of enteral feeds due to high gastric aspirates, were randomised to receive a 'study infusion' consisting of either neostigmine (0.4 mg/hr) or 0.9% saline. If, after 12 hours the patient was deemed intolerant of the nasogastric feed, the rate of the 'study infusion' was doubled. Those who remained intolerant after 24 hours of the 'study infusion' were 'crossed-over' and continued on the other infusion for a further 24 hours. Gastric emptying was assessed in each group before and after the infusion by measuring the hourly rates of feed "absorption" [(delivery rate + returned aspirates) - total aspirates] and paracetamol absorption using the area under a time-concentration curve at 120 minutes (AUC120). Differences within and between groups were analysed using Students t test and one-way analysis of variance.

RESULTS

Six patients received neostigmine first and 5 received the placebo first. Four of the 6 patients receiving the neostigmine first compared with all of those receiving placebo first required to be 'crossed-over' to the other infusion. While the hourly rates of feed "absorption" were greater for patients receiving neostigmine than for placebo, these differences did not achieve statistical significance. The mean paracetamol AUC120 for all patients who received neostigmine was 3996 mg/min/L while that for placebo was 1929 mg/min/L (p = 0.21).

CONCLUSIONS

These data suggest that while neostigmine may have a positive effect on gastric emptying and enteral feed absorption in critically ill patients, the results did not reach statistical significance and an adequately powered study will be required to confirm this effect.