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Paula Stewart

Publications and source records attributed to Paula Stewart.

8 recordsLinked to original sources

Ovine prion protein variant A(136)R(154)L(168)Q(171) increases resistance to experimental challenge with bovine spongiform encephalopathy agent.

Susceptibility and incubation periods of transmissible spongiform encephalopathies, such as scrapie in sheep, are modulated by the PrP gene. The standard model of association between ovine PrP genetics and classical scrapie susceptibility is based on PrP genotypes with respect to codons 136, 154 and 171, e.g. alanine-arginine-glutamine (ARQ). It is demonstrated here that a proline to leucine substitution in codon 168 of the ovine PrP protein gene is associated with increased resistance to experimental bovine spongiform encephalopathy (BSE) inoculation. The ARL(168)Q PrP allele was found in heterozygous ARP(168)Q/ARL(168)Q sheep that have so far survived intravenous BSE challenge three times longer than BSE-challenged homozygous ARP(168)Q/ARP(168)Q sheep, which develop disease in around 700 days. In contrast, the L141F polymorphism does not appear to be associated with susceptibility to intravenous BSE challenge.

Alleles↗

In a retrospective study of chronic obstructive pulmonary disease inpatients, respiratory comorbidities were significantly associated with prognosis.

BACKGROUND AND OBJECTIVE: Comorbidities may be related to the prognosis for chronic obstructive pulmonary disease (COPD). We examined respiratory comorbidities associated with length of stay and in-hospital mortality among COPD patients. METHODS: We used the Hospital Person Oriented Information (HPOI) database of Statistics Canada for a 5-year period. Over 4 years (fiscal years 1994-1995 to 1998-1999), 143,135 records listed COPD as the most responsible diagnosis for men and 122,065 records for women aged 40 years or more, and 75,780 men and 69,539 women were admitted to hospital at least once. Logistic regression modeling was used to examine the relationships between respiratory comorbidities and hospital outcomes adjusting for covariates. RESULTS: Of the COPD patients, 10% had pneumonia-influenza and 3% had asthma as comorbid conditions. Women had a higher prevalence of asthma than men. The median length of stay at hospital was approximately 7 days, and 95% of patients were discharged alive. The odds ratio (95% confidence interval) for pneumonia-influenza in relation to in-hospital death was 3.56 (3.31, 3.83) for men and 3.29 (3.00, 3.61) for women. For comorbid asthma the corresponding odds ratios were 0.56 (0.36, 0.61) and 0.54 (0.35, 0.57), respectively. CONCLUSIONS: COPD inpatients with pneumonia-influenza had a worse prognosis and those with asthma had a better prognosis.

Adult↗

Changing age-pattern of hospitalisation risk of chronic obstructive pulmonary disease in men and women in Canada.

OBJECTIVE: To examine the changing pattern of age distributions of hospitalisation for chronic obstructive pulmonary disease (COPD) among Canadian men and women. DESIGN: Retrospective cohort study. PARTICIPANTS: 257,604 COPD inpatients aged 55-90 years with 463,089 hospital admissions during a 3-year study period (1994/95, 1995/96 and 1996/97) in Canada. MAIN OUTCOME MEASURES: COPD listed as one of the first five underlying diagnoses (broad definition, 463,089 hospitalisations) or as first diagnosis (narrow definition, 142,770 hospitalisations). RESULTS: Overall, men were more likely to have hospitalisations for COPD and had a higher proportion of death at hospital than did women. The 3-year cumulative incidence was 42.2/1,000 for the broadly defined COPD hospitalisation and 14.0/1,000 for the narrowly defined COPD hospitalisation, and steadily increased with increasing age. The relative risk for women versus men gradually increased with decreasing age, and was significantly greater than unity in the 55-59 year group for narrowly defined COPD hospitalisation. CONCLUSIONS: In terms of impact on secondary care COPD is a disease of the elderly and is becoming more common in women, particularly in younger age groups.

Age Distribution↗

Ecological measures of socioeconomic status and hospital readmissions for asthma among Canadian adults.

BACKGROUND: Lack of an association between area-based socioeconomic status (SES) and readmission for asthma was investigated in a country with a universal health care system. METHODS: Data linkage analysis was conducted based on hospitalization data from Statistics Canada's Person-oriented Information Database and area-based SES data from the 1996 Census. Hospital records for 8333 asthma patients aged 20-64 years in all Canadian provinces except Quebec who were admitted in 1995/1996 were linked to determine the number of patients who were rehospitalized within the same fiscal year. The area-based SES of the patients was defined according to the average personal income and proportion of residents with a university degree in an enumeration area (EA). Incidence rates of readmission for asthma were calculated based on the total years at risk. Cox's proportional hazard model was used to adjust for age, sex, province, and length of stay for first admission. RESULTS: The incidence rate of asthma rehospitalization was 31.6 per 100 person-years for men and 37.2 per 100 person-years for women. Neither average EA income or education level was significantly associated with rehospitalization for asthma. Women living in poor areas tended to have an increased incidence of asthma rehospitalization, but the difference was not significant after adjustment for covariates using the Cox regression model. CONCLUSION: Socioeconomic status measured at the neighborhood level has no significant impact on rehospitalization for asthma among Canadian adults.

Adult↗

Hospital readmissions for asthma in children and young adults in Canada.

To examine the incidence rate of hospital readmission for asthma in relation to sex and age among Canadian children and young adults, we used data from 86,863 subjects under age 20 years when they had a first admission for asthma as 1 of first 5 diagnoses in Canada between April 1, 1994 and March 31, 1997. We calculated age- and sex-specific incidence rates, and used the Cox proportional hazards model for multivariate analysis. Of these subjects, 20,277 (23.3%) were readmitted to hospital for asthma during the study period. After adjusting for length of stay for first admission and province, the rate ratio for females vs. males was 0.86 for those under age 1 year, and close to unity for the 1-4-year and 5-9-year age groups, whereas it was 1.47 and 1.35 for the 10-14-year and 15-19-year age groups, respectively. The data showed similar trends for rehospitalization asthma as a primary diagnosis. The incidence rate of rehospitalization showed little sex difference between ages 1-9 years, but was markedly higher in females than in males 10-19 years of age. Airway size, female hormonal changes, increased use of cosmetic products, and cigarette smoking among adolescent girls may contribute to the age- and sex-differences in adolescence.

Adolescent↗

Sex difference in hospitalization due to asthma in relation to age.

To describe the sex and age differences in asthma hospitalization among the Canadian population, we conducted an analysis based on a total of 9,486,173 hospital records in Canada for a 3-year period (1994/1995, 1995/1996, and 1996/1997), including 204,304 asthma patients and 288,977 asthma-related records. Asthma as one of the first five diagnoses, accounted for 3.0% of total hospitalizations, which was almost constant across the 3-year study period. The 3-year cumulative incidence of asthma hospitalization was substantially higher for young boys than girls, and it was reversed for adults. The incidence ratio for females vs. males for asthma hospitalization reached 2.8 for individuals 25 to 34 years of age, decreased gradually with increasing age, and then approached unity for those aged 80 years or more. The data suggest that sex is an important determinant for asthma, and the sex effect varies considerably over a life span.

Adolescent↗

Community education on preterm birth. Does it change practice?

OBJECTIVE: To evaluate how well physicians and other prenatal care providers educate women about early recognition of and appropriate response to the signs and symptoms of preterm labour (PTL). To assess use of antenatal steroids for babies born at less than 34 weeks' gestation. DESIGN: Before-after study using a population-based approach. SETTING: Health care providers' offices, hospitals, and prenatal classes in Ottawa, Ont. PARTICIPANTS: Prenatal care providers, women in hospital after giving birth, prenatal class participants. INTERVENTIONS: Prenatal care providers received information and educational materials on PTL and preterm birth (PTB). They passed this information on to pregnant women at their 18- to 20-week prenatal visits. Teachers of prenatal classes gave the same information in early-series classes. Clinical practice guidelines were developed, and hospital staff received education on appropriate response to PTL. MAIN OUTCOME MEASURES: Use of educational materials and steroid treatment. RESULTS: Statistically significant increases were seen in the numbers of care providers who had educational material about PTL and PTB, who reported giving the educational material to all women, and who reported discussing signs and symptoms of PTL and PTB with all women; women who reported that their care providers talked with them about PTL and PTB, and women delivering preterm (< 34 weeks) babies who received steroids. CONCLUSION: Providing knowledge and standardized educational materials to health care providers can help improve preventive practice for PTL and educate women about PTL.

Female↗

State of the Art Compendium: Canadian Thoracic Society recommendations for the management of chronic obstructive pulmonary disease.

Chronic obstructive pulmonary disease (COPD) is a common cause of disability and death in Canada. Moreover, morbidity and mortality from COPD continue to rise, and the economic burden is enormous. The main goal of the Canadian Thoracic Society's evidence-based guidelines is to optimize early diagnosis, prevention and management of COPD in Canada. The main message of the guidelines is that COPD is a preventable and treatable disease. Targeted spirometry is strongly recommended to expedite early diagnosis in smokers and former smokers who develop respiratory symptoms, and who are at risk for COPD. Smoking cessation remains the single most effective intervention to reduce the risk of COPD and to slow its progression. Education, especially self-management plans, are key interventions in COPD. Therapy should be escalated on an individual basis in accordance with the increasing severity of symptoms and disability. Long-acting anticholinergics and beta-2-agonist inhalers should be prescribed for patients who remain symptomatic despite short-acting bronchodilator therapy. Inhaled steroids should not be used as first line therapy in COPD, but have a role in preventing exacerbations in patients with more advanced disease who suffer recurrent exacerbations. Acute exacerbations of COPD cause significant morbidity and mortality and should be treated promptly with bronchodilators and a short course of oral steroids; antibiotics should be prescribed for purulent exacerbations. Patients with advanced COPD and respiratory failure require a comprehensive management plan that incorporates structured end-of-life care. Management strategies, consisting of combined modern pharmacotherapy and nonpharmacotherapeutic interventions (eg, pulmonary rehabilitation and exercise training) can effectively improve symptoms, activity levels and quality of life, even in patients with severe COPD.

Canada↗