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Scott Klarenbach

Publications and source records attributed to Scott Klarenbach.

18 recordsLinked to original sources
PubMed2006

Residence location and likelihood of kidney transplantation.

BACKGROUND: In a universal, public health care system, access to kidney transplantation should not be influenced by residence location. We determined the likelihood of kidney transplantation from deceased donors among Canadian dialysis patients living in 7 geographic regions. Within each region we also determined whether distance from the closest transplant centre was associated with the likelihood of transplantation. METHODS: A random sample of 7034 subjects initiating dialysis in Canada between 1996 and 2000 was studied. We used Cox proportional hazards models to examine the relation between residence location and the likelihood of kidney transplantation from deceased donors over a median period of 2.4 years. RESULTS: There were significant differences in the likelihood of kidney transplantation from deceased donors and predicted waiting times between the different geographic regions. For example, the adjusted relative likelihood of transplantation in Alberta was 3.74 (95% confidence interval [CI] 2.95-4.76) compared with the likelihood in Ontario (p < 0.001). These differences persisted after further adjustment for differences in the rate of deceased organ donation. Within regions, patients who resided 50.1-150 km, 150.1-300 km and more than 300 km from the closest transplant centre had a similar adjusted likelihood of receiving a kidney transplant as those who lived less than 50 km away. INTERPRETATION: The adjusted likelihood of undergoing a kidney transplant from a deceased donor varied substantially between geographic regions in Canada. In contrast, the likelihood of transplantation within regions was not affected by distance from the closest transplant centre.

Aged↗
PubMed2006

The direct and indirect economic costs incurred by living kidney donors-a systematic review.

BACKGROUND: Despite the many benefits of living donor kidney transplantation, economic consequences can result for donors. We reviewed studies which quantified the direct and indirect costs incurred by living kidney donors, in order to understand the strengths and limitations of existing literature. METHODS: We identified relevant studies in MEDLINE, EMBASE and ECONOLIT bibliographic databases, in the Science Citation Index and study reference lists. Any study which reported at least one cost relevant to donors was included. The accuracy of abstracted data was verified by two reviewers and reported in year 2004 US dollars. RESULTS: Thirty-five studies from 12 countries described costs incurred by individuals who donated between the years 1964 and 2003. No study comprehensively quantified all relevant expenses-the sum of select costs considered in one US study averaged Dollars 837 per donor and ranged from Dollars 0 to 28,906. Travel and/or accommodation costs were incurred by 9-99% of donors, and were higher in countries with a larger land mass. Post-discharge analgesics were required by 4-24% of donors, but prescription costs were not reported. Between 14 and 30% of donors incurred costs for lost income, with an average loss of Dollars 3386 in one study from the UK and Dollars 682 in another study from the Netherlands. Costs for dependent care were incurred by 9-44% of donors, while costs for domestic help were incurred by 8% of donors. CONCLUSIONS: Donors incur many types of costs attributable to kidney donation and the total costs are certainly higher than previously reported. To guide informed consent and fair reimbursement policies, further data on all relevant costs, preferably from a detailed prospective multi-centre cohort study, are required.

Compensation and Redress↗
PubMed2006

The effects of nocturnal hemodialysis compared to conventional hemodialysis on change in left ventricular mass: rationale and study design of a randomized controlled pilot study.

BACKGROUND: Nocturnal hemodialysis (NHD) is an alternative to conventional three times per week hemodialysis (CvHD) and has been reported to improve several health outcomes. To date, no randomized controlled trial (RCT) has compared NHD and CvHD. We have undertaken a multi-center RCT in hemodialysis patients comparing the effect of NHD to CvHD on left ventricular (LV) mass, as measured by cardiac magnetic resonance imaging (cMR). METHODOLOGY/DESIGN: All patients in Alberta, Canada, expressing an interest in performing NHD are eligible for the study. Patients enrolled in the study will be randomized to either NHD or CvHD for a six month period. All patients will have a full clinical assessment, including collection of biochemical and cMR data at baseline and at 6 months. Both groups of patients will be monitored biweekly to optimize blood pressure (BP) to a goal of <130/80 mmHg post-dialysis using a predefined BP management protocol. The primary outcome is change in LV mass, a surrogate marker for cardiac mortality, measured at baseline and 6 months. The high sensitivity and reproducibility of cMR facilitates reduction of the required sample size and the time needed between measures compared with echocardiography. Secondary outcomes include BP control, anemia, mineral metabolism, health-related quality of life, and costs. DISCUSSION: To our knowledge, this study will be the first RCT evaluating health outcomes in NHD. The impact of NHD on LV mass represents a clinically important outcome which will further elucidate the potential benefits of NHD and guide future clinical endpoint studies.

Female↗
PubMed2006

A population-based analysis of healthcare utilization of persons with back disorders: results from the Canadian Community Health Survey 2000-2001.

STUDY DESIGN: A retrospective, population-based analysis. OBJECTIVES: To analyze the utilization of a variety of healthcare services for persons with and without a chronic back disorder, and to identify factors associated with specific patterns of healthcare resource use. SUMMARY OF BACKGROUND DATA: Although there have been studies of how chronic back disorders influence the use of specific healthcare services, we do not currently have a broad, population-based overview of how this condition influences healthcare service utilization. METHODS: Person-level data were taken from the 2000-2001 Canadian Community Health Survey (CCHS), a nationwide cross-sectional survey of health determinants, health status, and health system utilization of Canadians. A series of binary logistic regressions examining healthcare resource utilization were performed on a full study sample (n = 113,229), as well as a restricted sample (n = 36,713) with attention focused on subjects with a single diagnosis of a chronic back disorder. RESULTS: Persons with chronic back disorders were more likely to use physician resources (multivariate odds ratio [OR] = 1.2; 95% confidence interval, 1.1-1.2), and nonphysician resources (OR range, 2.1-3.6) compared with persons without the condition, with chiropractic care having an odds ratio of 3.6 (95% confidence interval, 3.5-3.8). Higher socioeconomic status, the presence of activity-limiting pain, and depressive symptoms were associated with a significant increase in utilization of almost all healthcare services. CONCLUSIONS: With increasing disability as indicated by the presence of pain and functional limitations, and the presence of depressive symptoms, the higher the utilization of physician and nonphysician resources, with the exception of chiropractic care, which appears to be used by those with less severe symptoms. Lower socioeconomic status was associated with significantly lower receipt of services for almost all healthcare providers.

Adult↗
PubMed2006

Impact of anemia on hospitalization and mortality in older adults.

Although anemia is common in older adults, its prognostic significance is uncertain. A total of 17 030 community-dwelling subjects 66 years and older were identified between July 1 and December 31, 2001, and followed until December 31, 2004. Cox proportional hazards analyses were performed to determine the associations between anemia (defined as hemoglobin < 110 g/L) and hemoglobin and all-cause mortality, all-cause hospitalization, and cardiovascular-specific hospitalization. Overall, there were 1983 deaths and 7278 first hospitalizations. In patients with normal kidney function, adjusting for age, sex, diabetes mellitus, and comorbidity, anemia was associated with an increased risk for death (hazard ratio [HR], 4.29; 95% confidence interval [CI], 3.55-5.12), first all-cause hospitalization (HR, 2.16; 95% CI, 1.88-2.48), and first cardiovascular-specific hospitalization (HR, 2.49; 95% CI, 1.99-3.12). An inverse J-shaped relationship between hemoglobin and all-cause mortality was observed; the lowest risk for mortality occurred at hemoglobin values between 130 to 150 g/L for women and 140 to 170 g/L for men. Anemia is associated with an increased risk for hospitalization and death in community-dwelling older adults. Consideration should be given to redefine "normal" hemoglobin values in the elderly. Clinical trials are also necessary to determine whether anemia correction improves quality or quantity of life in this population.

Aged↗
PubMed2006

Population-based analysis of obesity and workforce participation.

OBJECTIVE: To describe the relationship between obesity class and workforce participation and the influence of demographic, socioeconomic, and comorbid disease states on this relationship using population-based Canadian data. RESEARCH METHODS AND PROCEDURES: Responses from 73,531 adults surveyed in the Canadian Community Health Survey 2000 to 2001 who provided complete information regarding variables of interest were analyzed. Workforce participation was defined as individuals reporting that they held and were present at a job or business in the week before survey administration. The association between obesity and workforce participation was explored using logistic regression after adjusting for demographic, socioeconomic, and obesity-related comorbidities. RESULTS: In univariate analysis, obese individuals had lower odds of participating in the workforce. In the fully adjusted model, increasing obesity was associated with decreasing odds of workforce participation, with Class I, II, and III obesity having odds ratios (95% confidence interval) of 0.94 (0.89 to 0.99), 0.85 (0.77 to 0.94), and 0.66 (0.57 to 0.78), respectively. Obese individuals were also less likely to be employed and more likely to be absent from work. DISCUSSION: Obesity is associated with lower workforce participation. This association appears to be independent of associated comorbidity and sociodemographic factors. These results indicate that the economic impact of obesity alone on workforce productivity is larger than previous reports suggest.

Adult↗
PubMed2006

Differences in use of peritoneal dialysis and survival among East Asian, Indo Asian, and white ESRD patients in Canada.

BACKGROUND: Racial differences in health outcomes in general are well documented; however, few studies examined the impact of East Asian and Indo Asian race on choice of dialytic modality and survival among patients with end-stage renal disease (ESRD). METHODS: We compared the use of peritoneal dialysis (PD) and survival among East Asian, Indo Asian, and white patients with ESRD initiating dialysis therapy in Canada between January 1, 1990, and December 31, 2000. RESULTS: Of 10,338 patients, 5.7% were East Asian, 3.2% were Indo Asian, and 91% were white. After controlling for sociodemographics and comorbidities, East Asian and Indo Asian patients were significantly more likely to initiate dialysis therapy on PD compared with white patients (odds ratio, 1.63; 95% confidence interval [CI], 1.36 to 1.96; odds ratio, 1.52; 95% CI, 1.21 to 1.93, respectively), with no difference in likelihood of technique failure. East Asian and Indo Asian patients had a lower risk for death after the initiation of dialysis therapy (irrespective of modality) compared with white patients, with adjusted hazard ratios of 0.66 (95% CI, 0.58 to 0.76) for East Asian patients and 0.63 (95% CI, 0.53 to 0.75) for Indo Asian patients. The survival benefit for East Asian and Indo Asian patients was similar in the subgroup that initiated dialysis therapy with PD. CONCLUSION: We found that Asian patients with ESRD were more likely to initiate dialysis therapy using PD, with improved survival after the initiation of dialysis therapy, compared with white patients. Elucidation of factors in East Asian and Indo Asian ESRD populations that result in improved outcomes may have implications for ESRD treatment for other racial groups.

Aged↗
PubMed2005

Access flow in arteriovenous accesses by optodilutional and ultrasound dilution methods.

BACKGROUND: Most large studies evaluating the diagnostic properties of access blood flow (Qa) in arteriovenous (AV) accesses have used the Transonic HD01 (Transonic Systems Inc, Ithaca, NY) device, and recommended thresholds for angiography are based on data from these studies. There has been little exploration of how the use of other devices might affect the feasibility or performance of screening in AV accesses. METHODS: We compared 2 devices for measuring Qa: the Transonic HD01 and the Crit-Line TQA III (Hemametrics, Salt Lake City, UT). We studied 124 adults with end-stage renal disease and a functioning AV access (fistula or graft). Qa was measured with both devices in immediate succession during a single dialysis treatment. The primary outcome was the technical feasibility of the Qa measurement. We also compared mean Qa values measured by the Crit-Line III and Transonic devices. RESULTS: Qa measurements were less likely to be technically feasible when the Crit-Line III device was used compared with the Transonic device (86.3% versus 100%; P < 0.001). In patients with valid measurements, mean Qa measured using the Crit-Line III was significantly less than that measured using the Transonic HD01 device (886 +/- 557 versus 1,148 +/- 685 mL/min; P < 0.001). The mean difference was 261 mL/min (95% confidence interval [CI], 117 to 405) and was greater at higher levels of Qa. On average, Qa measured by means of the Crit-Line III device was 73% as high as that measured using the Transonic device (95% CI, 63 to 84). There was poor agreement between devices about whether criteria for angiography were met (kappa < 0.1). The proportion of patients for whom angiography was indicated (based on results from the Crit-Line device) was significantly greater than when only results from the Transonic device were considered (40.3% versus 7.3%; P < 0.001). CONCLUSION: Consideration should be given to device-specific Qa thresholds for angiography or, alternatively, standardization of Qa results between manufacturers. Clinicians should be aware that Qa results cannot be compared directly between different devices, and access monitoring should be performed using a single technique in any given patient. Additional studies are required before the Crit-Line TQA device can be recommended for widespread use.

Absorptiometry, Photon↗
PubMed2004

Establishment and maintenance of vascular access in incident hemodialysis patients: a prospective cost analysis.

Despite the importance of hemodialysis vascular access, the cost of vascular access care has not been studied in detail. A prospective cost analysis was performed among incident hemodialysis patients to determine the cost of vascular access care overall and on the basis of access type. Detailed clinical and demographic information, as well as data on access type, was collected for all local incident hemodialysis patients between July 1, 1999, and November 1, 2001. A comprehensive measure of total vascular access costs, including surgery, radiology, hospitalization for access complications, physician costs, costs for management of outpatient bacteremia, and vascular access monitoring costs, was obtained. Costs are reported in 2002 Canadian dollars (1 CAN dollar = 0.69 US dollar). A total of 239 consecutive incident hemodialysis patients were identified, 49, 157, and 33 of whom were dialyzed exclusively with a catheter or had a native arteriovenous fistula or synthetic graft attempted, respectively. In year 1, 18.4% of all hospital admissions were for vascular access-related complications. The mean cost of all vascular access care in year 1 was 6890 CAN dollars(median 4020 dollars; interquartile range [IQR] 2440 dollars to 7540 dollars). The mean cost of access care per patient-year at risk for maintaining a catheter exclusively, attempting an arteriovenous fistula, or attempting a graft was 9180 dollars (median 3812 dollars; IQR 2250 dollars to 7762 dollars), 7989 dollars (median 4641 dollars ; IQR 3035 dollars to 8832 dollars), and 11,685 dollars (median 8152 dollars; IQR 3395 dollars to 12,908 dollars), respectively (P = 0.01). Vascular access care is responsible for a significant proportion of health care costs in the first year of hemodialysis. These results support clinical practice guidelines that recommend preferential placement of a native fistula.

Aged↗
PubMed2004

A health production function for persons with back problems: results from the Canadian Community Health Survey of 2000.

STUDY DESIGN: A retrospective, population-based analysis. OBJECTIVES: To analyze the relation between health outcomes and resources used by persons with back problems in an everyday setting. SUMMARY OF BACKGROUND DATA: The Canadian Community Health Survey (2000) contains self-reported variables on change in health status, use of health resources, and socioeconomic characteristics of a population sample. METHODS: We use a health production function approach, in which we explore the association between change in health status and a series of utilization variables for persons with a single diagnosis of back pain using a regression equation. The independent variables include use of family physicians, chiropractors, physiotherapists, and exercise. RESULTS: Change in health status was negatively and significantly associated with family practice, chiropractic, and physiotherapy visits and positively associated with physical activity. The magnitudes of the results were small. CONCLUSIONS: Our results indicate that exercise is an important factor in back problems, while persons who seek formal care do not improve.

Adult↗
PubMed2004

Refining the measurement of the economic burden of chronic diseases in Canada.

This article presents an analysis of the economic burden of a number of chronic diseases in Canada. In the analysis, we adjusted our measure of utilization of physician and hospital services for co-existing chronic diseases, which we found to be widely prevalent and to have an impact on resource use. Using data from the 1999 National Population Health Survey, we developed resource use rankings for several chronic conditions and decomposed these measures into prevalence and per-person utilization components. Our results indicate that, for the diseases with the greatest impact, resource use measures are driven more by disease prevalence than intensity of resource use. The diseases with the highest overall degree of resource use are back pain, arthritis or rheumatism, high blood pressure and migraines for people under 60; and arthritis or rheumatism and high blood pressure for people over 60. Our methods can be used to forecast the overall relative impact of resource use due to disease prevalence and per-person resource use intensity for various conditions.

Adult↗
PubMed2003

Management of anemia with quotidian hemodialysis.

BACKGROUND: Most patients with end-stage renal disease have chronic anemia caused by inadequate erythropoietin (EPO) synthesis and require therapy with exogenous EPO to maintain recommended hematocrit and hemoglobin levels. METHODS: The London Daily/Nocturnal Hemodialysis Study compared anemia control among patients on either short daily, long nocturnal, or conventional thrice-weekly hemodialysis (HD) therapy. Patients were administered iron, either orally (900 mg/d) or intravenously (50 to 125 mg every 1 to 4 weeks), to maintain serum ferritin levels at greater than 45 ng/mL (100 microg/L) or transferrin saturations greater than 20%. EPO was administered by subcutaneous injection at frequencies ranging from twice weekly to once every second week to maintain hemoglobin levels within the target range of 11 to 12 g/dL (110 to 120 g/L). RESULTS: Both the daily HD and nocturnal HD study groups showed increased hemoglobin levels at later times compared with baseline levels, although only nocturnal HD patients had a statistically significant increase in hemoglobin levels at 18 months (11.94 g/dL [119.4 g/L] versus 10.95 g/dL [109.5 g/L] at baseline; P = 0.047). Both the daily HD and control groups showed a trend for decreased EPO dose requirements at later times compared with baseline, although these decreases were not statistically significant. The nocturnal HD group showed increased EPO dose requirements, although not statistically significant. CONCLUSION: Quotidian HD is associated with an increased quantity of blood loss that can account for some of the increased requirements in EPO dose. Additional studies with larger numbers of patients are needed to fully elucidate the effects of quotidian HD on anemia.

Adult↗
PubMed2002

The effect of renal insufficiency on workforce participation in the United States: an analysis using National Health and Nutrition Examination Survey III data.

BACKGROUND: End-stage renal disease is associated with workforce nonparticipation, but no previous study has assessed the impact of renal insufficiency on employment status from a population standpoint. METHODS: To determine whether renal insufficiency is independently associated with labor force participation, an analysis was performed using observational data from the Third National Health and Nutrition Examination Survey, which represents a cross-sectional sample of the US population. Five thousand five hundred fifty-eight subjects of the civilian noninstitutionalized US population aged 18 to 64 years provided complete information regarding key variables. A logistic regression equation with workforce participation as the dependent variable was created. Explanatory variables included age, sex, race, marital status, census region, and education, as well as the health-state indicators of general health status, presence or absence of diabetes, hypertension, stroke, congestive heart failure, myocardial infarction, and an indicator of renal function. Renal dysfunction was defined by serum creatinine values greater than 1.7 mg/dL (150 micromol/L) for women and greater than 2.0 mg/dL (180 micromol/L) for men. RESULTS: Renal dysfunction was independently associated with labor force nonparticipation, with an odds ratio of 7.94 (95% confidence interval, 1.60 to 39.43). This relationship remained statistically significant after subjects with markedly elevated serum creatinine levels were excluded. CONCLUSION: A previously unrecognized independent association between renal function and labor force participation was identified. This group of patients warrants further attention regarding identification of specific factors leading to nonemployment, potential for workforce rehabilitation, and assessment of the impact of renal insufficiency in other functional spheres.

Adolescent↗
PubMedDate not supplied

Reduced requirement for erythropoietin with quotidian hemodialysis therapy.

Quotidian (daily) hemodialysis has many potential advantages over conventional three times weekly hemodialysis, including improved control of anemia. However, previous reports do not consistently describe beneficial effects regarding anemia and erythropoietin requirements. We sought to determine whether erythropoietin dose is altered in this form of therapy, and elucidate the potential contributing factors. An analysis of an ongoing, nonrandomized, prospective trial of daily nocturnal, daily short, and their cohort of conventional hemodialysis controls was performed. Those patients who had completed 15 months of the trial were analyzed, which include nine patients in the quotidian dialysis group and nine cohort controls receiving conventional three times weekly dialysis. At 15 months, the weekly Kt/V in the quotidian group was 6.8 (+/-0.6) and 4.5 (+/-0.4) in the conventional group (p = 0.001). Mean erythropoietin dose fell in the quotidian group from 87 (+/-66) to 53 (+/-50) U/week per kg (p = 0.020). The mean hemoglobin rose from 115 (+/- 18) to 129 (+/- 14) g/L (p = 0.008). There was no significant change in erythropoietin dose or hemoglobin in the conventional hemodialysis group. Serum ferritin and the transferrin-saturation did not change significantly and remained above 100 microg/L and 20%, respectively, throughout. Serum albumin and C-reactive protein were similar between the quotidian and conventional dialysis groups and did not change over time. In patients who were receiving conventional thrice weekly hemodialysis, initiation of quotidian hemodialysis led to a 39% reduction in erythropoietin dose at 15 months, most likely due to the increased dose of delivered dialysis.

Adult↗
PubMedDate not supplied

Public investment in providing information for chronic disease prevention for adults in Alberta.

BACKGROUND: The World Health Organization in 2000 cited specific chronic diseases (chronic obstructive pulmonary disease, heart disease, diabetes and certain cancers) as major and preventable health hazards. There have subsequently been calls for increased investment in prevention activities. Currently there is no information on the economic magnitude of these promotion activities. In this study, we present an estimate of the investment in Alberta, by public organization, for chronic disease prevention activities which provide information that promotes behaviour changes in adults at risk. METHODS: We surveyed board members of the Alberta Healthy Living Network (AHLN) to obtain economic data and information on activities related to chronic disease (primary) prevention. We also asked for further contacts on programs in other agencies. We continued the ("snowball") process until no new agencies were identified. Agencies provided the information on a survey form. RESULTS: In 2003 in Alberta, the cost of publicly provided information to change risk behaviours related to chronic diseases for persons over 20 was dollars 24.9 million. This investment was diffused over a large number of bodies. Anti-smoking programs used the largest proportion of the money. The total cost per person at risk was about dollars 15. Regional Health Authorities spend about 1/10th of 1% of their budget on these activities. DISCUSSION: There are difficulties in collecting and organizing society-level data on chronic disease prevention. Nevertheless, all indications are that the amount of resources devoted in this area is small, and much smaller than has been suggested.

Adult↗