Effects of personal air pollution exposure on asthma symptoms, lung function and airway inflammation

BACKGROUND

There is evidence that air pollution increases the risk of asthma hospitalizations and healthcare utilization, but the effects on day-to-day asthma control are not fully understood.

OBJECTIVE

We undertook a prospective single-centre panel study to test the hypothesis that personal air pollution exposure is associated with asthma symptoms, lung function and airway inflammation.

METHODS

Thirty-two patients with a clinical diagnosis of asthma were provided with a personal air pollution monitor (Cairclip NO₂ /O₃ ) which was kept on or around their person throughout the 12-week follow-up period. Ambient levels of NO₂ and particulate matter were modelled based upon satellite imaging data. Directly measured ozone, NO₂ and particulate matter levels were obtained from a monitoring station in central Leicester. Participants made daily electronic records of asthma symptoms, peak expiratory flow and exhaled nitric oxide. Spirometry and asthma symptom questionnaires were completed at fortnightly study visits. Data were analysed using linear mixed effects models and cross-correlation.

RESULTS

Cairclip exposure data were of good quality with clear evidence of diurnal variability and a missing data rate of approximately 20%. We were unable to detect consistent relationships between personal air pollution exposure and clinical outcomes in the group as a whole. In an exploratory subgroup analysis, total oxidant exposure was associated with increased daytime symptoms in women but not men.

CONCLUSIONS AND CLINICAL RELEVANCE

We did not find compelling evidence that air pollution exposure impacts on day-to-day clinical control in an unselected asthma population, but further studies are required in larger populations with higher exposure levels. Women may be more susceptible than men to the effects of air pollution, an observation which requires confirmation in future studies.

Promoting Cardiovascular Health among Older Adults: A Pilot Study with Community Pharmacists

This project enabled us to develop procedures for organizing and running successful pharmacy blood pressure sessions. The knowledge gained from this pilot was used in the multicentred Community Health Awareness Program (CHAP).

Running blood pressure sessions in community pharmacies and using a multidisciplinary approach, including volunteer health educators and support from public health, was a feasible way to raise awareness of cardiovascular health among the older adults who participated in our project.

This pilot project included pharmacist involvement at several stages, from the planning of the blood pressure sessions and development of the documentation forms, to participation in the pilot and feedback after project completion. With its multidisciplinary approach, the pilot showed that it is feasible for a community pharmacist to be involved in research projects that can benefit patient care and enhance their professional roles.

Components of coordinated care

This article reports on the development of an instrument to measure dementia patients' and their families' experiences with care provision. Using the responses of 267 care recipient/caregiver dyads, exploratory factor analysis was used to extract an underlying structure of the dyads' assessments of their experiences with dementia networks of care. The results suggested that from the perspective of the care recipient and caregiver, it is the individuals who they interact with in their care journey that define and shape the evaluation of their experiences. In the early stages of dementia, the family physician plays a central role in helping dyads understand the disease and the networks of care that are available to them; in later stages of the disease, it is the activities of the health care worker who is central to the dyad's lived experiences of the care they are receiving. The third important construct linked to the period when a care recipient and caregiver dyad was increasingly aware that dementia services may be needed and the process of assessment and placement was underway. Having information about what resources are available and how they can be accessed, and being able to complete assessments and placements in a timely fashion, was central to their assessment of care networks.

The Impact of CME

A review of the literature evaluating the effectiveness of Continuing Medical Education (CME) was undertaken using articles from 1935 to 1982.238 studies were reviewed and annotated using previously established and tested assessment criteria. These criteria included the following areas: the study design; the educational or administrative intervention; the evaluation maneuver used to assess the intervention's outcome; the health professionals used as subjects; andfinally, the educational and statistical significance of the study. It would appear that CMEinterventions when broadly defied, have an impact on physician competence and (less consistently though still in a positive direction) on physician performance and patient outcomes. Further research in both the methods and evaluation of CME is necessary.

Pathology of Runting in Farmed Saltwater Crocodiles (Crocodylus porosus) in Australia

Extremely poor growth of some individuals within a birth cohort (runting) is a significant problem in crocodile farming. We conducted a pathological investigation to determine if infectious disease is associated with runting in farmed saltwater crocodiles ( Crocodylus porosus) and to look for evidence of other etiologies. In each of 2005 and 2007, 10 normal and 10 runt crocodiles, with an average age of 5.5 months and reared under identical conditions, were sampled. Laboratory testing included postmortem; histological examination of a wide variety of tissues (with quantitation of features that were noted subjectively to be different between groups); hematology; serum biochemistry (total protein, albumin, globulins, total calcium, phosphorus, and iron); bacterial culture of liver and spleen (2005 only); viral culture of liver, thymus, tonsil, and spleen using primary crocodile cell lines (2007 only); and serum corticosterone (2007 only). The only evidence of infectious disease was mild cutaneous poxvirus infection in 45% of normal and 40% of runt crocodiles and rare intestinal coccidia in 5% of normal and 15% of runt crocodiles. Bacterial and viral culture did not reveal significant differences between the 2 groups. However, runt crocodiles exhibited significant ( P < .05) increases in adrenocortical cell cytoplasmic vacuolation and serum corticosterone, decreased production of bone (osteoporosis), and reduced lymphoid populations in the spleen, tonsil, and thymus. Runts also exhibited moderate anemia, hypoalbuminemia, and mild hypophosphatemia. Taken together, these findings suggest an association between runting and a chronic stress response (hyperactivity of the hypothalamic-pituitary-adrenal axis).

Economic appraisal of a community-wide cardiovascular health awareness program

BACKGROUND

Cardiovascular disease (CVD) is a leading cause of hospitalizations, death, and health care costs. Although studies have shown that modifying CVD risk factors at the patient level improves patient prognosis, the effect of community-wide interventions at the population level has been uncertain.

OBJECTIVE

To evaluate the resource use and cost consequences of a community-wide Cardiovascular Health Awareness Program (CHAP).

METHODS

Thirty-nine medium-sized communities in Ontario, Canada, participated in a community cluster randomized controlled trial stratified by population size and geographic location. All community-dwelling elderly residents (>65 years) in each community were included. Family physicians, pharmacists, community nurses, local organizations, and volunteers in the intervention communities implemented the program. Rates and costs of CVD hospitalizations, all hospitalizations, emergency department visits, physician visits, and prescription medication use in the year before and after the intervention were compared for the 19 control and 20 CHAP communities by using province-wide linked administrative databases. The cost of implementing and administrating CHAP in each community was combined with total community health care cost to determine the net cost effect.

RESULTS

CHAP was associated with a reduction in CVD hospitalization costs. There were no differences in utilization rates or costs for overall hospitalizations, in visits to emergency rooms, physicians, or specialists, or in the use of prescription medications. Results were robust over a range of cost assumptions.

CONCLUSIONS

A community-wide CVD awareness program can be implemented and can reduce CVD-related hospitalization costs at the level of the community without a corresponding increase in overall health care costs.

Children's palliative care: a global concern

Children's palliative care (CPC) is a specialty in itself, albeit closely related to adult palliative care (World Health Organization (WHO), 2002). However, although there are many children who require palliative care, in much of the world CPC has a poor profile and is inaccessible to those who need it (Downing et al, 2010; Knapp et al, 2011). The provision of high-quality palliative care for children is a global concern, with 27% of the world population being under the age of 15, rising to as many as 49% in countries such as Uganda (WHO, 2010). It has been estimated that as many as 7 million of these children around the world will need palliative care each year (Rushton et al, 2002), although the true figure is likely to be higher. The public health approach to palliative care is key to the development of CPC services, as is the development of models that integrate services into existing health structures.

Issues associated with the use of modified texture foods

Use of modified texture foods (MTF) is common in the geriatric population. There is a potential for increased prevalence of use of MTF due in part to longer survival of persons with dementia, those who have suffered from a stroke, as well as other degenerative diseases that affect chewing and swallowing. Unfortunately, little clinical, nutritional and sensory research has been conducted on MTF to inform practice. This review highlights issues identified in the literature to date that influence nutritional and sensory quality and acceptability of these foods. Use of MTF is highly associated with undernutrition, however causality is difficult to demonstrate due to confounding factors such as the requirement for feeding assistance. Knowledge gaps and considerations that need to be taken into account when conducting research are identified.

Knowledge-to-action processes in SHRTN collaborative communities of practice: a study protocol

Background

The Seniors Health Research Transfer Network (SHRTN) Collaborative is a network of networks that work together to improve the health and health care of Ontario seniors. The collaborative facilitates knowledge exchange through a library service, knowledge brokers (KBs), local implementation teams, collaborative technology, and, most importantly, Communities of Practice (CoPs) whose members work together to identify innovations, translate evidence, and help implement changes.

This project aims to increase our understanding of knowledge-to-action (KTA) processes mobilized through SHRTN CoPs that are working to improve the health of Ontario seniors. For this research, KTA refers to the movement of research and experience-based knowledge between social contexts, and the use of that knowledge to improve practice. We will examine the KTA processes themselves, as well as the role of human agents within those processes. The conceptual framework we have adopted to inform our research is the Promoting Action on Research Implementation in Health Services (PARIHS) framework.

Methods/design

This study will use a multiple case study design (minimum of nine cases over three years) to investigate how SHRTN CoPs work and pursue knowledge exchange in different situations. Each case will yield a unique narrative, framed around the three PARIHS dimensions: evidence, context, and facilitation. Together, the cases will shed light on how SHRTN CoPs approach their knowledge exchange initiatives, and how they respond to challenges and achieve their objectives. Data will be collected using interviews, document analysis, and ethnographic observation.

Discussion

This research will generate new knowledge about the defining characteristics of CoPs operating in the health system, on leadership roles in CoPs, and on the nature of interaction processes, relationships, and knowledge exchange mechanisms. Our work will yield a better understanding of the factors that contribute to the success or failure of KTA initiatives, and create a better understanding of how local caregiving contexts interact with specific initiatives. Our participatory design will allow stakeholders to influence the practical usefulness of our findings and contribute to improved health services delivery for seniors.

Cloning and pharmacological characterization of the dog P2X7 receptor

BACKGROUND AND PURPOSE

Human and rodent P2X7 receptors exhibit differences in their sensitivity to antagonists. In this study we have cloned and characterized the dog P2X7 receptor to determine if its antagonist sensitivity more closely resembles the human or rodent orthologues.

EXPERIMENTAL APPROACH

A cDNA encoding the dog P2X7 receptor was isolated from a dog heart cDNA library, expressed in U-2 OS cells using the BacMam viral expression system and characterized in electrophysiological, ethidium accumulation and radioligand binding studies. Native P2X7 receptors were examined by measuring ATP-stimulated interleukin-1beta release in dog and human whole blood.

KEY RESULTS

The dog P2X7 receptor was 595 amino acids long and exhibited high homology (>70%) to the human and rodent orthologues although it contained an additional threonine at position 284 and an amino acid deletion at position 538. ATP possessed low millimolar potency at dog P2X7 receptors. 2'-&3'-O-(4benzoylbenzoyl) ATP had slightly higher potency but was a partial agonist. Dog P2X7 receptors possessed relatively high affinity for a number of selective antagonists of the human P2X7 receptor although there were some differences in potency between the species. Compound affinities in human and dog blood exhibited a similar rank order of potency as observed in studies on the recombinant receptor although absolute potency was considerably lower.

CONCLUSIONS AND IMPLICATIONS

Dog recombinant and native P2X7 receptors display a number of pharmacological similarities to the human P2X7 receptor. Thus, dog may be a suitable species for assessing target-related toxicity of antagonists intended for evaluation in the clinic.

Riding the wave of primary care research: development of a primary health care research centre

PROBLEM BEING ADDRESSED

Family medicine departments and primary health care research centres across the country are growing in size and complexity and therefore require increasingly sophisticated management strategies. Conducting effective and relevant research relies on a stable and efficient organization. OBJECTIVE OF THE PROGRAM To focus on the needs of individuals, teams, and the organization in order to ensure the success of research projects.

PROGRAM DESCRIPTION

In order to ensure the success of research projects, the C.T. Lamont Primary Health Care Research Centre (CTLC) in Ottawa, Ont, used the following strategies: ensuring organizational support (ie, protected time for research and sustained funding for some investigators); arranging financial and infrastructure support; building skills and confidence (eg, education sessions); organizing linkages and collaborations (eg, forums among staff members); creating appropriate dissemination (eg, newsletter, website); and providing continuity and sustainability.

CONCLUSION

In order to ensure progress in primary health care research, the CTLC created solutions that focused on the individual, team, and organizational levels. With its management strategies, the CTLC was successful in maintaining a high-functioning team and a well-organized research organization.

Comparison of Bayesian and classical methods in the analysis of cluster randomized controlled trials with a binary outcome: the Community Hypertension Assessment Trial (CHAT)

Background

Cluster randomized trials (CRTs) are increasingly used to assess the effectiveness of interventions to improve health outcomes or prevent diseases. However, the efficiency and consistency of using different analytical methods in the analysis of binary outcome have received little attention. We described and compared various statistical approaches in the analysis of CRTs using the Community Hypertension Assessment Trial (CHAT) as an example. The CHAT study was a cluster randomized controlled trial aimed at investigating the effectiveness of pharmacy-based blood pressure clinics led by peer health educators, with feedback to family physicians (CHAT intervention) against Usual Practice model (Control), on the monitoring and management of BP among older adults.

Methods

We compared three cluster-level and six individual-level statistical analysis methods in the analysis of binary outcomes from the CHAT study. The three cluster-level analysis methods were: i) un-weighted linear regression, ii) weighted linear regression, and iii) random-effects meta-regression. The six individual level analysis methods were: i) standard logistic regression, ii) robust standard errors approach, iii) generalized estimating equations, iv) random-effects meta-analytic approach, v) random-effects logistic regression, and vi) Bayesian random-effects regression. We also investigated the robustness of the estimates after the adjustment for the cluster and individual level covariates.

Results

Among all the statistical methods assessed, the Bayesian random-effects logistic regression method yielded the widest 95% interval estimate for the odds ratio and consequently led to the most conservative conclusion. However, the results remained robust under all methods – showing sufficient evidence in support of the hypothesis of no effect for the CHAT intervention against Usual Practice control model for management of blood pressure among seniors in primary care. The individual-level standard logistic regression is the least appropriate method in the analysis of CRTs because it ignores the correlation of the outcomes for the individuals within the same cluster.

Conclusion

We used data from the CHAT trial to compare different methods for analysing data from CRTs. Using different methods to analyse CRTs provides a good approach to assess the sensitivity of the results to enhance interpretation.

Influenza vaccination and decisional conflict among regulated and unregulated direct nursing care providers in long-term-care homes

The purpose of this study was to determine whether direct nursing care providers have decisional conflict about receiving influenza vaccinations and characteristics associated with decisional conflict. The researchers used a self-administered questionnaire mailed to direct nursing care providers in two long-term-care organizations. Most direct nursing care providers in both organizations (80% and 93%, respectively) intended to get the influenza vaccine. Unregulated direct nursing care providers had more decisional conflict than regulated providers, especially related to feeling uninformed about the pros and cons of influenza vaccination. Unclear valuing of the pros and cons of influenza vaccination was related to the age of the direct care providers in both organizations. Decisional conflict and influenza vaccination practices may be determined, in part, by age and by the culture of a health care organization. A decision aid to improve knowledge and clarify values may improve decision quality and increase influenza vaccination rates.

Blood Pressure Awareness and Self-Monitoring Practices among Primary Care Elderly Patients

Background:

Seniors are perceived as relatively passive recipients of health care, and levels and predictors of blood pressure awareness and self-monitoring in these patients are poorly understood.

Objectives:

To determine the extent to which seniors are aware of their blood pressure status and targets and to examine correlates of blood pressure awareness and self-monitoring.

Methods:

We conducted a cross-sectional analysis of a 32-item baseline questionnaire that was completed by patients aged 65 years and older who were attending pharmacy-based cardiovascular health promotion sessions. The study comprised sociodemographic data, as well as data on health-related quality of life, knowledge of current blood pressure readings and targets, and treatment and monitoring of blood pressure in the previous year.

Results:

Of the 983 respondents, 379 (38.5%) recalled their most recent blood pressure reading. For one-third of these respondents (323/983), their physicians relayed blood pressure targets; of these, 26.9% (87/323) reported targets consistent with current guidelines. Overall, 47.1% (463/983) reported monitoring blood pressure in the past year. Multivariate logistic regression analysis revealed that older patients (aged 80 years and older) were less likely to know their blood pressure readings, compared with those who were younger. Patients with a postsecondary education, those who were diagnosed with high blood pressure, and those who were told their target blood pressure were more apt to know their readings, relative to those less educated, undiagnosed, or unaware of their target blood pressure. Participants who were aged 80 years and older were a negative predictor of self-monitoring in multivariate analysis, whereas living with someone, previous diagnosis of high blood pressure, and being advised of their target blood pressure were positive predictors.

Conclusion:

Seniors had a relatively poor understanding of their blood pressure readings and targets, but a subset was considerably more knowledgeable and potentially suited to be more involved in blood pressure self-management.

Understanding the influence of the complex relationships among informal and formal supports on the well-being of caregivers of persons with dementia

This study examined the direct and indirect relationships between caring for a person with dementia and caregiver health. A conceptual model of the caregiver stress process considered informal caregiver characteristics, sources of caregiver stress, and the influence of informal and formal support on the well-being of the caregivers of persons with dementia. Structural equation modeling was used to test specific hypotheses in a sample of 327 caregivers of people with dementia who were living in the community, as part of the first wave of the Canadian Study of Health and Aging. Our findings show that the negative impact of the increasing disability of the care recipient on the psychological well-being of the caregiver was mediated mostly by the use of informal support systems and marginally by the use of formal support systems. The use of informal support by caregivers was associated with a decreased use of formal supports. The relationship between caregiver characteristics and their psychological health was mediated by the use of formal support but not by the use of informal support systems.

Degradation of extracellular matrix components by defined proteinases from the greenbottle larva Lucilia sericata used for the clinical debridement of non-healing wounds

BACKGROUND

Larvae of the greenbottle fly Lucilia sericata are used routinely for the clinical treatment of difficult necrotic and infected wounds. Degradation by proteinases contained in larval excretory/secretory (ES) products is thought to contribute to wound debridement by removal of dead tissue. However, proteinase activity may also affect host tissue remodelling processes.

OBJECTIVES

To identify proteolytic enzymes derived from L. sericata ES products with activities against fibrin and extracellular matrix (ECM) components.

METHODS

Larval proteinase activities were assayed in vitro using class-specific substrates and inhibitors. Their action against fibrin and ECM components was examined using sodium dodecyl sulphate-polyacrylamide gel electrophoresis.

RESULTS

Three classes of proteolytic enzyme were detected in the secretions using fluorescein isothiocyanate-labelled casein as a model substrate. The predominant activity belonged to serine proteinases (pH optima 8-9) of two different subclasses (trypsin-like and chymotrypsin-like), with a weaker aspartyl proteinase (pH 5) and a metalloproteinase (pH 9) with exopeptidase characteristics also present. Using skin-relevant ECM components as substrates L. sericata ES products solubilized fibrin clots and degraded fibronectin, laminin and acid-solubilized collagen types I and III. Hydrolysis of ECM macromolecules was inhibited by preincubating ES products with phenylmethylsulphonyl fluoride but not 4-amidinophenylmethylsulphonyl fluoride, indicating that degradation was due to the 'chymotrypsin-like' serine proteinase.

CONCLUSIONS

These data suggest that a combination of L. sericata ES proteinases involving chymotrypsin-like and trypsin-like activities could potentially influence wound healing events when maggots are introduced into necrotic and infected wounds, with the chymotrypsin-like activity involved in the remodelling of ECM components.

Factors associated with long-term institutionalization of older people with dementia: data from the Canadian Study of Health and Aging

BACKGROUND

In Canada, half the people with dementia live in institutions. Factors associated with institutionalization should be identified with the goal of implementing strategies not only to permit those with dementia to stay in their homes as long as is feasible but also to ensure that steps are taken for timely institutionalization when appropriate.

METHODS

Informal caregivers of 326 individuals with dementia living in the community were identified and interviewed as part of the Canadian Study of Health and Aging (CSHA). These subjects were contacted again 2.5 and 5 years after the baseline interview to collect information on the status of their care recipients. Survival analyses using clinical data for the individuals with dementia and data from the interviews with their informal caregivers were carried out using Cox proportional hazard modeling to estimate the hazard ratio (HR).

RESULTS

Over the 5-year period, 166 individuals with dementia (50.9%) were institutionalized and the median time to admission was 41 months. From the multivariate analysis, the factors significantly associated with institutionalization were: type of dementia (Alzheimer's disease: HR = 1.83), severity of disability (mild: 1.51; moderate: 2.34; total impairment: 4.02), caregiver's age over 60 (1.83), caregiver not a spouse or child (1.55), and severe caregiver burden (1.71). Caregiver's burden was associated with the care-receiver's behavioral disturbance (partial r =.55) and the caregiver's depressive mood (r =.55).

CONCLUSIONS

Screening caregivers for burden and depression and designing interventions to decrease the consequences of behavioral disturbance on caregivers would be relevant avenues to explore to decrease institutionalization of people with dementia.

Reproductive changes in fluctuating house mouse populations in southeastern Australia

House mice (Mus domesticus) in the Victorian mallee region of southeastern Australia show irregular outbreaks. Changes in reproductive output that could potentially drive changes in mouse numbers were assessed from 1982 to 2000. Litter size in females is positively correlated with body size. When standardized to an average size female, litter size changes seasonally from highest in spring to lowest in autumn and winter. Litter size is depressed throughout breeding seasons that begin when the abundance of mice is high, but is similar in breeding seasons over which the abundance of mice increases rapidly or remains low. Breeding begins early and is extended on average by about five weeks during seasons when mouse abundance increases rapidly. The size at which females begin to reproduce is larger during breeding seasons that begin when mouse abundance is high. An extended breeding season that begins early in spring is necessary for the generation of a house mouse plague, but it is not in itself sufficient. Reproductive changes in outbreaks of house mice in Australia are similar but not identical to reproductive changes that accompany rodent population increases in the Northern Hemisphere. We conclude that food quality, particularly protein, is a probable mechanism driving these reproductive changes, but experimental evidence for field populations is conflicting.

Short-term adverse health effects in a community exposed to a large polyvinylchloride plastics fire

The purpose of this study was the documentation of the short-term morbidity and mortality experiences of an urban community exposed to the airborne byproducts of a large polyvinylchloride plastics fire. The authors administered a survey to representatives of each household who had lived in an area evacuated during the fire. A time-series analysis was performed on emergency room visits and admissions for all hospitals in the city. Chloracne surveillance was instituted. Sixty-two percent of the individuals surveyed from the evacuation area reported no health concerns or symptoms related to the fire. Thirty-eight percent of the residents reported symptoms, and less than 2% of those surveyed reported that they sought medical attention for their health concerns. There was no evidence of increased hospital admissions or emergency room use during and immediately following the fire. No cases of chloracne were reported, and no deaths or serious injuries occurred during the fire. Polyvinylchloride plastics recycling plants pose potential health hazards to civilian populations. Public health authorities should be prepared to assess population health status rapidly and to disseminate relevant health information in a timely way during a crisis.