Marie DesMeules

Hemodialysis versus peritoneal dialysis: A comparison of adjusted mortality rates

Although kidney transplantation is the preferred treatment method for patients with ESRD, most patients are placed on dialysis either while awaiting transplantation or as their only therapy. The question of which dialytic method provides the best patient survival remains unresolved. Survival analyses comparing hemodialysis and continuous ambulatory peritoneal dialysis/continuous cyclic peritoneal dialysis (CAPD/CCPD), a newer and less costly dialytic modality, have yielded conflicting results. Using data obtained from the Canadian Organ Replacement Register, we compared mortality rates between hemodialysis and CAPD/CCPD among 11,970 ESRD patients who initiated treatment between 1990 and 1994 and were followed-up for a maximum of 5 years. Factors controlled for include age, primary renal diagnosis, center size, and predialysis comorbid conditions. The mortality rate ratio (RR) for CAPD/CCPD relative to hemodialysis, as estimated by Poisson regression, was 0.73 (95% confidence interval: 0.68 to 0.78). No such relationship was found when an intent-to-treat Cox regression model was fit. Decreased covariable-adjusted mortality for CAPD/CCPD held within all subgroups defined by age and diabetes status, although the RRs increased with age and diabetes prevalence. The increased mortality on hemodialysis compared with CAPD/CCPD was concentrated in the first 2 years of follow-up. Although continuous peritoneal dialysis was associated with significantly lower mortality rates relative to hemodialysis after adjusting for known prognostic factors, the potential impact of unmeasured patient characteristics must be considered. Notwithstanding, we present evidence that CAPD/CCPD, a newer and less costly method of renal replacement therapy, is not associated with increased mortality rates relative to hemodialysis.

Socioeconomic status and cardiovascular disease: risks and implications for care

Socioeconomic status (SES) refers to an individuals social position relative to other members of a society. Low SES is associated with large increases in cardiovascular disease (CVD) risk in men and women. The inverse association between SES and CVD risk in high-income countries is the result of the high prevalence and compounding effects of multiple behavioral and psychosocial risk factors in people of low SES. However, strong and consistent evidence shows that parental SES, childhood and early-life factors, and inequalities in health services also contribute to elevated CVD risk in people of low SES who live in high-income countries. In addition, place of residence can affect CVD risk, although the data on the influence of wealth distribution and work-related factors are inconsistent. Studies on the effects of SES on CVD risk in low-income and middle-income countries is scarce, but evidence is emerging that the increasing wealth of these countries is beginning to lead to replication of the patterns seen in high-income countries. Clinicians should address the association between SES and CVD by incorporating SES into CVD risk calculations and screening tools, reducing behavioral and psychosocial risk factors via effective and equitable primary and secondary prevention, undertaking health equity audits to assess inequalities in care provision and outcomes, and by use of multidisciplinary teams to address risk factors over the life course.

Individual, social, environmental, and physical environmental correlates with physical activity among Canadians: a cross-sectional study

BackgroundThe identification of various individual, social and physical environmental factors affecting physical activity (PA) behavior in Canada can help in the development of more tailored intervention strategies for promoting higher PA levels in Canada. This study examined the influences of various individual, social and physical environmental factors on PA participation by gender, age and socioeconomic status, using data from the 2002 nationwide survey of the Physical Activity Monitor.MethodsIn 2002, 5,167 Canadians aged 15–79 years, selected by random-digit dialling from household-based telephone exchanges, completed a telephone survey. The short version of the International Physical Activity Questionnaire was used to collect information on total physical activity. The effects of socio-economical status, self-rated health, self-efficacy, intention, perceived barriers to PA, health benefits of PA, social support, and facility availability on PA level were examined by multiple logistic regression analyses.ResultsSelf-efficacy and intention were the strongest correlates and had the greatest effect on PA. Family income, self-rated health and perceived barriers were also consistently associated with PA. The effects of the perceived health benefits, education and family income were more salient to older people, whereas the influence of education was more important to women and the influence of perceived barriers was more salient to women and younger people. Facility availability was more strongly associated with PA among people with a university degree than among people with a lower education level. However, social support was not significantly related to PA in any subgroup.ConclusionThis study suggests that PA promotion strategies should be tailored to enhance peoples confidence to engage in PA, motivate people to be more active, educate people on PAs health benefits and reduce barriers, as well as target different factors for men and women and for differing socio-economic and demographic groups.

Age- and sex-related prevalence of diabetes mellitus among immigrants to Ontario, Canada

Background: The majority of immigrants to Canada originate from the developing world, where the most rapid increase in prevalence of diabetes mellitus is occurring. We undertook a population-based study involving immigrants to Ontario, Canada, to evaluate the distribution of risk for diabetes in this population. Methods: We used linked administrative health and immigration records to calculate age-specific and age-adjusted prevalence rates among men and women aged 20 years or older in 2005. We compared rates among 1 122 771 immigrants to Ontario by country and region of birth to rates among long-term residents of the province. We used logistic regression to identify and quantify risk factors for diabetes in the immigrant population. Results: After controlling for age, immigration category, level of education, level of income and time since arrival, we found that, as compared with immigrants from western Europe and North America, risk for diabetes was elevated among immigrants from South Asia (odds ratio [OR] for men 4.01, 95% CI 3.82–4.21; OR for women 3.22, 95% CI 3.07–3.37), Latin America and the Caribbean (OR for men 2.18, 95% CI 2.08–2.30; OR for women 2.40, 95% CI: 2.29–2.52), and sub-Saharan Africa (OR for men 2.31, 95% CI 2.17–2.45; OR for women 1.83, 95% CI 1.72–1.95). Increased risk became evident at an early age (35–49 years) and was equally high or higher among women as compared with men. Lower socio-economic status and greater time living in Canada were also associated with increased risk for diabetes. Interpretation: Recent immigrants, particularly women and immigrants of South Asian and African origin, are at high risk for diabetes compared with long-term residents of Ontario. This risk becomes evident at an early age, suggesting that effective programs for prevention of diabetes should be developed and targeted to immigrants in all age groups.

Meat and Fish Consumption and Cancer in Canada

In this study, we examined the association between meat and fish intake and the risk of various cancers. Mailed questionnaires were completed by 19,732 incident, histologically confirmed cases of cancer of the stomach, colon, rectum, pancreas, lung, breast, ovary, prostate, testis, kidney, bladder, brain, non-Hodgkins lymphomas (NHL), and leukemia and 5,039 population controls between 1994 and 1997 in 8 Canadian provinces. Measurement included information on socioeconomic status, lifestyle habits, and diet. A 69-item food frequency questionnaire provided data on eating habits 2 yr before data collection. Odds ratios and 95% confidence intervals were derived through unconditional logistic regression. Total meat and processed meat were directly related to the risk of stomach, colon, rectum, pancreas, lung, breast (mainly postmenopausal), prostate, testis, kidney, bladder, and leukemia. Red meat was significantly associated with colon, lung (mainly in men), and bladder cancer. No relation was observed for cancer of the ovary, brain, and NHL. No consistent excess risk emerged for fish and poultry, which were inversely related to the risk of a number of cancer sites. These findings add further evidence that meat, specifically red and processed meat, plays an unfavorable role in the risk of several cancers. Fish and poultry appear to be favorable diet indicators.

A review of the cost of cardiovascular disease

In Canada, 74,255 deaths (33% of all deaths) in 2003 were due to cardio-vascular disease (CVD). As one of the most costly diseases, CVD represents a major economic burden on health care systems. The purpose of the present study was to review the literature on the economic costs of CVD in Canada and other developed countries (United States, Europe and Australia) published from 1998 to 2006, with a focus on Canada. Of 1656 screened titles and abstracts, 34 articles were reviewed including six Canadian studies and 17 American studies. While considerable variation was observed among studies, all studies indicated that the costs of treating CVD-related conditions are significant, outlining a convincing case for CVD prevention programs.

A meta-analysis of randomized control trials of home-based secondary prevention programs for coronary artery disease.

Background A variety of different types of secondary prevention programs for coronary heart disease (CHD) exist. Home-based programs have become more common and may be more accessible or preferable to some patients. This review compared the benefits and costs of home-based programs with usual care and cardiac rehabilitation. Methods A meta-analysis following a systematic search of 19 databases, existing reviews, and references was designed. Studies evaluated home-based interventions that addressed more than one main CHD risk factor using a randomized trial with a usual care or cardiac rehabilitation comparison group with data extractable for CHD patients only and reported in English as a full article or thesis. Results Thirty-nine articles reporting 36 trials were reviewed. Compared with usual care, home-based interventions significantly improved quality of life [weighted mean difference: 0.23; 95% confidence interval (95% CI): 0.02-0.45], systolic blood pressure (weighted mean difference: − 4.36mmHg; 95% CI: − 6.50 to − 2.22), smoking cessation (difference in proportion: 14%; 95% CI: 0.02-0.26), total cholesterol (standardized mean difference: − 0.33; 95% CI: − 0.57 to − 0.08), and depression (standardized mean difference: − 0.33; 95% CI: − 0.59 to − 0.07). Effect sizes were small to moderate and trials were of low-to-moderate quality. Comparisons with cardiac rehabilitation could not be made because of the small number of trials and high levels of heterogeneity. Conclusion Home-based secondary prevention programs for CHD are an effective and relatively low-cost complement to hospital-based cardiac rehabilitation and should be considered for stable patients less likely to access or adhere to hospital-based services. Eur J Cardiovasc Prev Rehabil 17:261-270

Migration and health in Canada: health in the global village

Background: Immigration has been and remains an important force shaping Canadian demography and identity. Health characteristics associated with the movement of large numbers of people have current and future implications for migrants, health practitioners and health systems. We aimed to identify demographics and health status data for migrant populations in Canada. Methods: We systematically searched Ovid MEDLINE (1996–2009) and other relevant web-based databases to examine immigrant selection processes, demographic statistics, health status from population studies and health service implications associated with migration to Canada. Studies and data were selected based on relevance, use of recent data and quality. Results: Currently, immigration represents two-thirds of Canada’s population growth, and immigrants make up more than 20% of the nation’s population. Both of these metrics are expected to increase. In general, newly arriving immigrants are healthier than the Canadian population, but over time there is a decline in this healthy immigrant effect. Immigrants and children born to new immigrants represent growing cohorts; in some metropolitan regions of Canada, they represent the majority of the patient population. Access to health services and health conditions of some migrant populations differ from patterns among Canadian-born patients, and these disparities have implications for preventive care and provision of health services. Interpretation: Because the health characteristics of some migrant populations vary according to their origin and experience, improved understanding of the scope and nature of the immigration process will help practitioners who will be increasingly involved in the care of immigrant populations, including prevention, early detection of disease and treatment.

Neonatal characteristics as risk factors for preschool asthma

Childhood asthma usually begins early in life. Neonatal characteristics are reportedly predictive of symptom onset. This investigation utilized data from a provincial health organization to evaluate the effect of several birth characteristics on asthma incidence and hospitalization for asthma during age 0-4. Using logistic regression, the odds ratios (OR) for the following variables indicate a significant (p < 0.05) association with physician-diagnosed preschool asthma: male gender (OR = 1.72), birthweight < 1500 g (OR = 2.11), prematurity (OR = 1.34), respiratory distress syndrome (RDS) in the presence (OR = 2.95) or absence (OR = 1.61) of bronchopulmonary dysplasia (BPD), and transient tachypnea of the newborn (TTN; OR = 1.36). Male gender (OR = 1.91), birthweight < 1500 g (OR = 2.56), RDS with and without BPD (OR = 3.35 and 2.50, respectively), TTN (OR = 2.08), and severe birth asphyxia (OR = 1.94) showed an important association with hospitalization due to asthma. Neonatal characteristics are important determinants for the risk of preschool asthma, even after mutual adjustment.

Survival experience among elderly end-stage renal disease patients. A controlled comparison of transplantation and dialysis.

Renal transplantation is a relatively recent treatment option among the elderly with end-stage renal disease (ESRD). Since little is known regarding the clinical benefits of transplantation relative to dialysis in this age group, this study compares transplantation and dialysis among the elderly with respect to patient survival. Data utilized in this investigation were obtained from the Canadian Organ Replacement Register (CORR). The study population consisted of the 6400 patients aged 60 and over at registration, diagnosed between 1987 and 1993, for whom data on comorbid conditions were available. Survival probability, death rates, age-standardized mortality ratios (SMRs) and Cox regression analysis were employed to evaluate the survival experience among the transplant and dialysis groups. Transplant recipients were matched (by age, underlying diagnosis leading to ESRD, and number of comorbid conditions) to 2 randomly selected patients who did not undergo transplantation. Using Cox regression, the time-dependent hazard ratio for transplantation versus dialysis patients was estimated at 0.47 (P < 0.0001), indicating that even after adjusting for other known prognostic factors, elderly patients who received a transplant experienced significantly greater survival probability than those who remained on dialysis. When transplant patients were matched to randomly selected dialysis patients with the constraint that the corresponding dialysis patient have at least as much follow-up time as the transplant patient had waiting time, five-year survival rates were 81% and 51% for the transplant and dialysis groups, respectively (P < 0.0001). These results support the potential advantage of transplantation among the elderly, and may have important implications for renal care in this age group.