Validation of an obstetric comorbidity index in an external population.

OBJECTIVES: An obstetric comorbidity index has been developed recently with superior performance characteristics relative to general comorbidity measures in an obstetric population. This study aimed to externally validate this index and to examine the impact of including hospitalisation/delivery records only when estimating comorbidity prevalence and discriminative performance of the obstetric comorbidity index. DESIGN: Validation study. SETTING: Alberta, Canada. POPULATION: Pregnant women who delivered a live or stillborn infant in hospital (n = 5995). METHODS: Administrative databases were linked to create a population-based cohort. Comorbid conditions were identified from diagnoses for the delivery hospitalisation, all hospitalisations and all healthcare contacts (i.e. hospitalisations, emergency room visits and physician visits) that occurred during pregnancy and 3 months pre-conception. Logistic regression was used to test the discriminative performance of the comorbidity index. MAIN OUTCOME MEASURES: Maternal end-organ damage and extended length of stay for delivery. RESULTS: Although prevalence estimates for comorbid conditions were consistently lower in delivery records and hospitalisation data than in data for all healthcare contacts, the discriminative performance of the comorbidity index was constant for maternal end-organ damage [all healthcare contacts area under the receiver operating characteristic curve (AUC) = 0.70; hospitalisation data AUC = 0.67; delivery data AUC = 0.65] and extended length of stay for delivery (all healthcare contacts AUC = 0.60; hospitalisation data AUC = 0.58; delivery data AUC = 0.58). CONCLUSIONS: The obstetric comorbidity index shows similar performance characteristics in an external population and is a valid measure of comorbidity in an obstetric population. Furthermore, the discriminative performance of the comorbidity index was similar for comorbidities ascertained at the time of delivery, in hospitalisation data or through all healthcare contacts.

Factors that influence the childbearing intentions of Canadian men.

BACKGROUND: The role of men in the childbearing decision process and the factors that influence men's childbearing intentions have been relatively unexplored in the literature. This study aimed to describe the factors that strongly influence the childbearing intentions of men and to describe differences in these factors according to men's age group. METHODS: A telephone survey (response rate 84%) was conducted with 495 men between the ages of 20 and 45 living in an urban setting who, at the time of contact, did not have biological children. Men were asked about what factors strongly influence their intention to have children. Univariable and multivariable logistic regressions were conducted to determine if these factors were significantly associated with age. RESULTS: Of those sampled, 86% of men reported that at some point in the future they planned to become a parent. The factors that men considered to be most influential in their childbearing intentions were: the need to be financially secure, their partner's interest/desire to have children, their partner's suitability to be a parent and their personal interest/desire to have children. Men who were 35-45 years old had lower odds of stating that financial security (crude OR: 0.32, 95% CI: 0.18-0.54) and partner's interest in having children (crude OR: 0.57, 95% CI: 0.33-0.99) were very influential, but had higher odds of stating that their biological clock (crude OR: 4.37, 95% CI: 1.78-10.76) was very influential in their childbearing intentions than men in the 20-24 year age group. CONCLUSIONS: The factors that influence men's intentions about when to become a parent may change with age. Understanding what influences men to have children, and what they understand about reproductive health is important for education, program and policy development.

Reducing obesity and related chronic disease risk in children and youth: a synthesis of evidence with 'best practice' recommendations.

Childhood obesity is a global epidemic and rising trends in overweight and obesity are apparent in both developed and developing countries. Available estimates for the period between the 1980s and 1990s show the prevalence of overweight and obesity in children increased by a magnitude of two to five times in developed countries (e.g. from 11% to over 30% in boys in Canada), and up to almost four times in developing countries (e.g. from 4% to 14% in Brazil). The goal of this synthesis research study was to develop best practice recommendations based on a systematic approach to finding, selecting and critically appraising programmes addressing prevention and treatment of childhood obesity and related risk of chronic diseases. An international panel of experts in areas of relevance to obesity provided guidance for the study. This synthesis research encompassed a comprehensive search of medical/academic and grey literature and the Internet covering the years 1982-2003. The appraisal approach developed to identify best practice was unique, in that it considered not only methodological rigour, but also population health, immigrant health and programme development/evaluation perspectives in the assessment. Scores were generated based on pre-determined criteria with programmes scoring in the top tertile of the scoring range in any one of the four appraisal categories included for further examination. The synthesis process included identification of gaps and an analysis and summary of programme development and programme effectiveness to enable conclusions to be drawn and recommendations to be made. The results from the library database searches (13,158 hits), the Internet search and key informant surveys were reduced to a review of 982 reports of which 500 were selected for critical appraisal. In total 158 articles, representing 147 programmes, were included for further analysis. The majority of reports were included based on high appraisal scores in programme development and evaluation with limited numbers eligible based on scores in other categories of appraisal. While no single programme emerged as a model of best practice, synthesis of included programmes provided rich information on elements that represent innovative rather than best practice under particular circumstances that are dynamic (changing according to population subgroups, age, ethnicity, setting, leadership, etc.). Thus the findings of this synthesis review identifies areas for action, opportunities for programme development and research priorities to inform the development of best practice recommendations that will reduce obesity and chronic disease risk in children and youth. A lack of programming to address the particular needs of subgroups of children and youth emerged in this review. Although immigrants new to developed countries may be more vulnerable to the obesogenic environment, no programmes were identified that specifically targeted their potentially specialized needs (e.g. different food supply in a new country). Children 0-6 years of age and males represented other population subgroups where obesity prevention programmes and evidence of effectiveness were limited. These gaps are of concern because (i) the pre-school years may be a critical period for obesity prevention as indicated by the association of the adiposity rebound and obesity in later years; and (ii) although the growing prevalence of obesity affects males and females equally; males may be more vulnerable to associated health risks such as cardiovascular disease. Other gaps in knowledge identified during synthesis include a limited number of interventions in home and community settings and a lack of upstream population-based interventions. The shortage of programmes in community and home settings limits our understanding of the effectiveness of interventions in these environments, while the lack of upstream investment indicates an opportunity to develop more upstream and population-focused interventions to balance and extend the current emphasis on individual-based programmes. The evidence reviewed indicates that current programmes lead to short-term improvements in outcomes relating to obesity and chronic disease prevention with no adverse effects noted. This supports the continuation and further development of programmes currently directed at children and youth, as further evidence for best practice accumulates. In this synthesis, schools were found to be a critical setting for programming where health status indicators, such as body composition, chronic disease risk factors and fitness, can all be positively impacted. Engagement in physical activity emerged as a critical intervention in obesity prevention and reduction programmes. While many programmes in the review had the potential to integrate chronic disease prevention, few did; therefore efforts could be directed towards better integration of chronic disease prevention programmes to minimize duplication and optimize resources. Programmes require sustained long-term resources to facilitate comprehensive evaluation that will ascertain if long-term impact such as sustained normal weight is maintained. Furthermore, involving stakeholders in programme design, implementation and evaluation could be crucial to the success of interventions, helping to ensure that needs are met. A number of methodological issues related to the assessment of obesity intervention and prevention programmes were identified and offer insight into how research protocols can be enhanced to strengthen evidence for obesity interventions. Further research is required to understand the merits of the various forms in which interventions (singly and in combination) are delivered and in which circumstances they are effective. There is a critical need for the development of consistent indicators to ensure that comparisons of programme outcomes can be made to better inform best practice.

Regional differences in the replication rate of cultured rat microvascular endothelium from retroperitoneal and epididymal fat pads.

Study of the vascular endothelium has been greatly facilitated by the development of specific cell culture systems isolated from various tissues. We report herein a simple method for establishing a propagating cell culture system of microvascular endothelial cells derived from rat adipose tissue. In addition to the characteristic cobblestone appearance on light microscopy, the microvascular endothelial cells in culture also demonstrated the presence of other markers for large vessel endothelia. Electron microscopy revealed endothelium-specific Weibel-Palade bodies and abundant pinocytotic vesicles. Both retroperitoneal and epididymal endothelia demonstrated the presence of factor VIII antigen by immunofluorescent staining and prostacyclin production. Although there was no appreciable morphological difference between cultured retroperitoneal and epididymal microvascular endothelia, the replication rate of the former was significantly higher than that of the latter (P less than .05). Excessive replication of endothelial cells may play a role in the regional differences of adipose tissue mass in an organism.

Factors that influence emergency department visits for asthma.

BACKGROUND: Asthma can usually be controlled through allergen avoidance and/or appropriate medication. An emergency department visit for an acute exacerbation of asthma often represents a breakdown in asthma management. Emergency department treatment results in significant health care expenditures and reflects a compromised quality of life. OBJECTIVES: To identify risk factors associated with an emergency department visit for asthma. METHODS: This case-control study compared 299 people (76% of 390 cases contacted) who attended one of two emergency departments in Alberta in 1992 and 1993 for an acute exacerbation of asthma (cases) with 212 unmatched community controls with asthma who were located by random digit dialing. Cases and controls were asked to complete a mailed questionnaire to obtain data regarding severity, visits to doctors and emergency departments, medication use, allergies and other triggers, and smoking history. Data analysis included bivariate analysis of risk factors and multivariate model development using logistic regression. RESULTS: The response rate was similar between cases and controls. Cases were younger than controls (odds ratio [OR] 2.16, 95% CI 1.34 to 3.48) and more often reported their asthma to be severe (OR 4.25, 95% CI 2.24 to 8.06), and had experienced nocturnal symptoms (stratified OR range 1.36 to 6.82). Cases used more health care services in the previous year, had been admitted to hospital at some time for asthma (OR 1.62, 95% CI 1.10 to 2.38) and used more medication than controls. CONCLUSIONS: Physicians and other health care workers should be sensitive to the risk factors and target interventions to high risk individuals.

Characteristics of preterm delivery and low birthweight among 113,994 infants in Alberta: 1994-1996.

This study examined the impact of infant and maternal factors on preterm delivery and low birthweight (LBW) in Alberta between January 1, 1994 and December 31, 1996. Data on 113,994 births were collected from vital statistics registration birth data. Logistic regression models for preterm and LBW delivery suggested the key risk factors were multiple and still birth (odds ratios > 22.0). Other characteristics included female gender, birth defects, nulliparous women, maternal age 35 and greater, unmarried, history of abortion, maternal smoking, maternal street drug use, and having less than 4 prenatal visits (odds ratios 0.86-2.54). Interactions between smoking and alcohol, and smoking and parity were noted. Efforts to improve the currently low rates (8.2%) of smoking cessation during pregnancy are required. Social, economic and medical factors associated with delayed childbearing and birth outcomes should be investigated.

Street drug use during pregnancy: potential programming effects on preschool wheeze.

Street drug use during pregnancy is detrimental to fetal development. Although the prevalence of wheeze is high in offspring of substance-abusing mothers, nothing is known about the role of street drug use during pregnancy in its development. We investigated the impact of maternal street drug use and distress during pregnancy on the development of wheeze and allergy in preschool children. Questionnaire data were accessed from the Community Perinatal Care trial of 791 mother-child pairs in Calgary, Alberta. Using logistic regression, the association between maternal substance use and distress during pregnancy, and wheeze and allergy at age 3 years was determined in boys and girls. After adjusting for alcohol use during pregnancy, pre- and postnatal tobacco use, preterm birth, duration of exclusive breastfeeding, daycare attendance and maternal socioeconomic status, maternal street drug use during pregnancy [odds ratio (OR): 5.02, 95% confidence interval (CI): 1.30-19.4] and severe maternal distress during pregnancy (OR: 5.79, 95% CI: 1.25-26.8) were associated with wheeze in girls. In boys, an independent association was found between severe distress during pregnancy (OR: 3.85, 95% CI: 1.11-13.3) and allergies, but there was no association with maternal street drug use. In conclusion, we found an association between maternal street drug use and wheeze in preschool girls that could not be accounted for by maternal distress, smoking or alcohol use during pregnancy. Prenatal programming effects of street drugs may explain this association.

A review of 19 fatal injuries associated with backcountry skiing.

A review of circumstances surrounding 19 backcountry deaths in Alberta, Canada, between 1980 and 1991 suggests several factors that increase the risk of injury or death. This study provides a descriptive profile of a fatally injured backcountry skier and the circumstances surrounding his or her death. The individual most likely to suffer a fatal injury while participating in a backcountry ski activity is a 36-year-old man. He is typically an experienced backcountry skier who chooses to ski in areas where the avalanche hazard is known to be moderate to extreme. Delineating the personal characteristics of those at risk for backcountry injury and identifying situations that put them at risk will enable better design of education programs. Targeting high-risk groups may also reduce the incidence of death from this activity.

A review of fatal injuries associated with downhill skiing.

Reviewed here are those circumstances surrounding 18 downhill skiing deaths in Alberta, Canada. Variables that elevate the risk of injury and death are highlighted. This study profiles the fatally injured skier. The individual most likely to die while downhill skiing is an experienced male skier, average age 31 years. He loses control while skiing too fast and strikes an object, resulting in fatal blunt trauma injuries. The ability to define characteristics of the individual at risk of a fatal ski injury is important to the design and implementation of injury prevention programs. Public education targeted to those at risk may reduce the incidence of death and injury in downhill skiing.

A review of fatal bear maulings in Alberta, Canada.

Occasionally, encounters with a grizzly or a black bear have proved fatal. We describe the characteristics of fatal bear maulings and the circumstances that provoked them. The actions of wild bears are compared with those of bears that have become comfortable around people (wild/"habituated" bears). A description of eight deaths that occurred in the province of Alberta, Canada, between 1973 and 1988 will underscore the above.

Horse-related fatalities in the Province of Alberta, 1975-1990.

People use horses for work and recreational purposes on farms and ranches in Alberta, Canada. This retrospective descriptive review examines the records of all those people killed while around horses between 1975 and 1990. The intent is to ascertain features common to these injuries and to suggest prevention strategies. Records from the Office of the Chief Medical Examiner of Alberta revealed that 38 people were involved in horse-related fatalities between 1975 and 1990 and that 22 died of head injuries. All 38 deaths were classified as accidental. Some of these might have been prevented, or injuries might have been minimized by riders' wearing approved riding helmets. Public education encouraging the proper use of protective headgear is necessary if there is to be a reduction in the severity of these injuries.

Breast milk supplementation for preterm infants: parental preferences and postdischarge lactation duration.

Breast milk supplementation is frequently used to improve preterm infant growth and to achieve satisfactory intakes of minerals and vitamins. In the North American market there are commercial preparations: two powders and a liquid. The nutritional data available suggest these products are similar and their utilization is based on healthcare team choice. Parental perception about supplementation has not been previously evaluated although parental attitudes are known to impact on lactation success. The objectives of this paper are to determine parental preference and breastfeeding duration for very-low-birth-weight infants given commercial breast milk enrichment products. The study design is a randomized clinical trial with parental interviews. Sixty-three families with 71 infants were enrolled. Parents expressed their preference for the addition of a powder over a liquid preparation (p<0.01). Those mothers whose infants received the liquid enrichment had a shorter lactation relative to their goal, compared with the mothers of the infants who received the powder (p = 0.017). Parents prefer a powder product for breast milk supplementation and this choice positively impacts on the duration of breastfeeding for very-low-birth-weight infants.

Autoerotic asphyxial deaths: analysis of nineteen fatalities in Alberta, 1978 to 1989.

This paper presents an unusual form of sexual (masturbatory) activity and brings this unusual cause of death to wider medical attention and understanding. All 19 cases of autoerotic asphyxial death that occurred between 1978 and 1989 in the province of Alberta, Canada were reviewed. The fatal victim of autoerotic asphyxia is typically a single male aged 15 to 29 years. Autoerotic sexual activity is typically performed in isolation; often there is evidence of repetitive practice. The accidental death usually results when the "safety" mechanism designed to alleviate neck compression fails. Often the first sign of the activity (usually a surprise to family and friends) is death itself. Physicians who are alert to the practice may suggest counselling when patients present with sexual concerns, unusual marks around the neck or evidence of abrasions to limbs suggesting bondage or other masochistic practices.

Effects of in vitro fertilization on low birth weight, preterm delivery, and multiple birth.

PURPOSE: To quantify the contribution of in vitro fertilization (IVF) on changes in the rates of low birth weight (LBW), preterm delivery, very low birth weight, and multiple births during the past 3 years. METHODS: Data on IVF pregnancies from 1994 to 1996 within Alberta were reviewed. Population data were obtained from the Provincial notice of a live or stillbirth. RESULTS: The IVF component of increased LBW rate in the province was 17.8% for infants <2500 g and 43.5% for those born <1500 g. IVF accounted for 10.5% of the provincial rate increase in deliveries <37 weeks' gestation and 66.2% of those <30 weeks' gestation. IVF accounted for 21.4% of the twins and all of the sets of triplets in the province. CONCLUSION: During a 3-year period IVF has affected the incidence of LBW, preterm delivery, and multiple birth. IVF is a substantial contributor to changes in very low birth weight and delivery before 30 weeks, which is partly related to multiple births.

Influence of paracrine factors on preadipocyte replication and differentiation.

Regional adipose tissue growth may be modulated by paracrine factors that influence preadipocyte replication and/or differentiation. To investigate this hypothesis, we have studied the effects of culture media conditioned by adipose microvascular endothelial cells, preadipocytes, or mature fat cells, on rat preadipocyte replication and differentiation in vitro. Endothelial cell-conditioned medium (ECCM) stimulated preadipocyte replication while medium conditioned by mature fat or preadipocytes had little effect. ECCM contained heat and trypsin sensitive polypeptides, with molecular masses in the 18-35 kDa range. Mature fat-conditioned medium, but not medium enriched with triacylglycerols, induced differentiation in about 50 percent of preadipocytes. This effect was greatly reduced in cells derived from genetically obese JCR:LA-corpulent (cp) rats compared to those derived from lean JCR:LA-cp or Sprague-Dawley rats. The present studies demonstrate the presence of paracrine factors which may play a role in regulating regional adipose tissue growth.

Sudden death from asthma in 108 children and young adults.

To identify factors that may contribute to asthma mortality, 108 acute asthma deaths were reviewed. Information was obtained from medical records, next-of-kin, and autopsy records. The fatal asthmatic was characterized by early-onset asthma, severe disease requiring systemic corticosteroids, and prior hospitalization. Risk factors associated with gender, season, employment, and region were also identified. The fatal attack was characterized by an identifiable trigger, delay in seeking medical attention, and rapid deterioration in clinical status. Death due to asthma was confirmed in 95% of autopsied cases. Adrenal cortical abnormalities were recorded for 18.7% of cases. We conclude that, in addition to established risk factors, complications associated with the use of systemic steroids may contribute to the risk for sudden death in this age group.

Features that distinguish those who die from asthma from community controls with asthma.

To evaluate risk factors for asthma mortality, an unmatched case-control study was undertaken in the Canadian prairie provinces of Alberta, Saskatchewan, and Manitoba. Those between the ages of 5 and 50 (inclusive) who died from an acute exacerbation of asthma were compared to a control group of people with asthma from the same geographical areas who were contacted using random-digit dialing. Because no deaths occurred among residents less than 15 years old, this analysis was limited to cases and controls between 15 and 50 years old. Of the 38 deaths that occurred between November 1992 and October 1995, data were obtained from next of kin for 35 (92.1%). Of the 210 potential controls that were identified, 142 returned completed questionnaires (67.6%). Cases were more likely than controls to have asthma reported to be severe, to have experienced nocturnal symptoms, to have had cardiopulmonary resuscitation (CPR)/intubation, and to have had more healthcare utilization in the previous year. Medication use was also more common among cases compared to controls. Specific asthma triggers were reported more often for cases than controls; weather changes, excitement, depression, and stress showed the greatest case control differences. Although a number of very strong risk factors for death from asthma were identified, death from asthma is so rare in this age group that it is not possible to label an individual as "likely" to die from asthma. Nonetheless, patients, caregivers, and health professionals should be aware of indicators that would suggest greater risk.

Maternal haemolysis, elevated liver enzymes and low platelets syndrome: perinatal and neurodevelopmental neonatal outcomes for infants weighing less than 1250 g.

OBJECTIVES: To study mortality and short-term morbidity of infants born to women with HELLP (haemolysis, elevated liver enzymes, and low platelets) syndrome and to compare the long-term neurodevelopmental morbidity of a subgroup with birth weight (BWT) less than 1250 g (study group) with weight matched controls. METHODS: Retrospective chart review and prospective neurodevelopmental follow-up through a Perinatal Follow-up clinic. Analysis of perinatal and neonatal data for women diagnosed with HELLP from 1993 to 1996. Neurodevelopmental outcome for the study group was compared to a group of weight matched controls. RESULTS: A total of 109 infants (mean gestational age 32.6 weeks, mean BWT 1766 g) were born to 104 women with HELLP syndrome. There was a significant decrease in mortality (P = 0.002) and morbidity (P < 0.05) with increasing gestational age and birthweight. No significant differences in neonatal mortality and morbidity were present between the infants weighing less than 1250 g study and weight matched control group. However, at 3 years, the study group had fewer children with cerebral palsy (P = 0.024) and mental disability (P trend = 0.07). Mean cognitive index was 99 versus 91 in the controls (P = 0.101). CONCLUSION: Improved health outcomes occur with increased gestational age. Infants with BWT less than 1250 g born to women with HELLP syndrome were not at risk of increased neurodevelopmental disability compared to controls.