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Background: A large clinical dataset of vitamin B12 measurements (over 12,000 patients) and Schilling tests (over 700 patients) has been assembled from participating Manitoba laboratories (1995–2000) in order to assess clinical outcomes (as defined from administrative health data) in relation to tests of cobalamin [Cbl] deficiency. In order to control for Cbl replacement, it is necessary to confirm that Cbl replacement can be accurately determined from administrative data sources such as the Drug Program Information Network (DPIN) and/or medical claims for therapeutic injections. DPIN is known to be reliable for oral prescription drugs, but parenteral Cbl may be more difficult to identify and non-prescription oral Cbl would not be recorded. We believe that the preferred route of Cbl administration in Manitoba was parenteral during 1995–2000, but this needs to be confirmed. Methods: Cases (expected to have a high likelihood for Cbl replacement) consisted of all adult hospital discharges between 1995 and 2000 with a diagnosis of pernicious anemia or other Cbl deficiency anemia (ICD-9-CM 281.0, 281.1) who survived for at least one year post-discharge without personal care home admission (n=388). Matched controls (3 controls for each case) with a low likelihood for Cbl replacement were similarly defined from hospital discharges without any ICD-9-CM neurologic or haematologic diagnosis (n=1,164). Controls were matched with cases for gender, birth year and hospitalization year. For each case and control the number of Cbl dispensations (ATC code B03BA01) and therapeutic injections (tariff code #8954) were tabulated during the first three years post-discharge. Sensitivities (fraction of cases receiving Cbl replacement) and specificities (fraction of controls not receiving Cbl replacement) were calculated for different cutoffs of Cbl dispensations, therapeutic injections and combinations according to year of diagnosis (YOD) and overall. Weighted linear regression between YOD and sensitivity was performed to look for an effect of recent oral Cbl replacement. Results: Sensitivity for the a priori operational definition (≥2 Cbl dispensations) was 0.59±0.02 with specificity 0.96±0.01. Using one or more Cbl dispensations improved sensitivity to 0.71±0.02 with similar specificity of 0.95±0.01. Therapeutic injections alone were less useful (≥1 injection sensitivity of 0.65±0.02 with specificity of 0.92±0.01, ≥2 injections sensitivity of 0.61±0.02 with specificity of 0.95±0.01). The combination that maximized sensitivity + specificity was ≥1 dispensation or ≥2 therapeutic injections (sensitivity 0.80±0.02, specificity 0.93±0.01). Sensitivity measurements did not show any significant relationship with YOD. Conclusions: The optimal definition for Cbl therapy based upon administrative health data appears to be at least one Cbl dispensation identified in the DPIN database or at least two therapeutic injections identified from medical claims. In assessing clinical outcomes in relation to Cbl testing and replacement, we propose to validate findings derived with the primary combined definition through secondary analyses using independent definitions of Cbl replacement (≥1 dispensation alone or ≥2 therapeutic injections alone). Overall sensitivity was lower than expected but may reflect that some cases are not prescribed Cbl replacement post-discharge. Sensitivity was unrelated to YOD arguing against oral Cbl replacement as the explanation.

Background and Methods: In 1996 we created the population-based University of Manitoba IBD Database. In 1997 there were 5102 subjects in this database who were current residents of Manitoba. In 1994, Manitoba Health established the Drug Program Information Network (DPIN) which identified all ambulatory prescription drugs (Rx) dispensed to each individual resident of the province. All residents have a personal health identification number and use of this number in a scrambled format allowed for linkage of the IBD database with the DPIN database. We analyzed all Rx and costs for fiscal year 1997, & stratified our analysis by age, gender, urban vs. non-urban residence & by income. Results: 87.5% of subjects received Rx in 1997 (IBD users). There was a direct significant relationship between increasing age and # different Rx IIBD user and total Rx costslIBD user (in adults only). Females used a greater # of different Rxluser but there was no difference in costs/user by gender. There was no difference in # different Rx/user or costs/user for urban vs non-urban residence or by income level. Increased age was associated with increased # different Rx for the following classes of drugs: alimentary, cardiovascular, respiratory, neural, but no difference by age for the use of immunomodulatory, antibiotics, musculoskeletal, dermatologic, hematologic, g-u or hormonal drugs. Only 7.8% used immunomodulatory Rx but these accounted for the greatest cost/user ($1404). The next most costly class was alimentary Rx at $534/user; used by 64.5%. There was increased # alimentary Rxluser with increasing age. Conclusions: Gender and urban residence do not impact on prescription drug use of IBD patients. There is increased use of Rx, including alimentary Rx with age but no differences in immunomodulatory, or antibiotic Rx. (Supported by the Crohn's Colitis Foundation Canada)

Background Population-based administrative data have been used to study osteoporosis-related fracture risk factors and outcomes, but there has been limited research about the validity of these data for ascertaining fracture cases. The objectives of this study were to: (a) compare fracture incidence estimates from administrative data with estimates from population-based clinically-validated data, and (b) test for differences in incidence estimates from multiple administrative data case definitions. Methods Thirty-five case definitions for incident fractures of the hip, wrist, humerus, and clinical vertebrae were constructed using diagnosis codes in hospital data and diagnosis and service codes in physician billing data from Manitoba, Canada. Clinically-validated fractures were identified from the Canadian Multicentre Osteoporosis Study (CaMos). Generalized linear models were used to test for differences in incidence estimates. Results For hip fracture, sex-specific differences were observed in the magnitude of under- and over-ascertainment of administrative data case definitions when compared with CaMos data. The length of the fracture-free period to ascertain incident cases had a variable effect on over-ascertainment across fracture sites, as did the use of imaging, fixation, or repair service codes. Case definitions based on hospital data resulted in under-ascertainment of incident clinical vertebral fractures. There were no significant differences in trend estimates for wrist, humerus, and clinical vertebral case definitions. Conclusions The validity of administrative data for estimating fracture incidence depends on the site and features of the case definition.

Background Traditional non-steroidal anti-inflammatory drugs (NSAIDs) are a widely used class of therapy in the treatment of chronic pain and inflammation. The drugs are effective and can be relatively inexpensive thanks to available generic versions. Unfortunately the traditional NSAIDs are associated with gastrointestinal complications in a small proportion of patients, requiring costly co-therapy with gastro-protective agents. Recently, a new class of non-steroidal anti-inflammatory agents known as coxibs has become available, fashioned to be safer than the traditional NSAIDs but priced considerably higher than the traditional generics. To help physicians choose appropriately and cost-effectively from the expanded number of anti-inflammatory therapies, scientific bodies have issued clinical practice guidelines and third party payers have published restricted reimbursement policies. The objective of this study is to determine whether an educational intervention can prompt physicians to adjust their prescribing in accordance with these expert recommendations. Methods This is an ongoing, randomized controlled trial. All primary care physicians in Manitoba, Canada have been randomly assigned to a control group or an intervention study group. The educational intervention being evaluated consists of an audit and feedback mechanism combined with optional participation in a Continuing Medical Education interactive workshop. The primary outcome of the study is the change, from pre-to post-intervention, in physicians' appropriate prescribing of non-steroidal anti-inflammatory therapies for patients requiring chronic treatment. Three classes of non-steroidal anti-inflammatory therapies have been identified: coxib therapy, traditional NSAID monotherapy, and traditional NSAID therapy combined with gastro-protective agents. Appropriate prescribing is defined based on international clinical practice guidelines and the provincial drug reimbursement policy in Manitoba.

Background Increased 99mTc-sestamibi stress lung-to-heart ratio (sLHR) has been shown to predict cardiac outcomes similar to pulmonary uptake of thallium. Peak heart rate and use of pharmacologic stress affect the interpretation of lung thallium uptake. The current study was performed to determine whether 99mTc-sestamibi sLHR measurements are affected by stress-related variables, and whether this in turn affects prognostic utility. Methods sLHR was determined in 718 patients undergoing 99mTc-sestamibi SPECT stress imaging. sLHR was assessed in relation to demographics, hemodynamic variables and outcomes (mean follow up 5.6 ± 1.1 years). Results Mean sLHR was slightly greater in males than in females (P < 0.01) and also showed a weak negative correlation with age (P < 0.01) and systolic blood pressure (P < 0.01), but was unrelated to stress method or heart rate at the time of injection. In patients undergoing treadmill exercise, sLHR was also positively correlated with peak workload (P < 0.05) but inversely with double product (P < 0.05). The combined explanatory effect of sex, age and hemodynamic variables on sLHR was less than 10%. The risk of acute myocardial infarction (AMI) or death increased by a factor of 1.7–1.8 for each SD increase in unadjusted sLHR, and was unaffected by adjustment for sex, age and hemodynamic variables (hazard ratios 1.6–1.7). The area under the ROC curve for the unadjusted sLHR was 0.65 (95% CI 0.59–0.71, P < 0.0001) and was unchanged for the adjusted sLHR (0.65, 95% CI 0.61–0.72, P < 0.0001). Conclusion Stress-related variables have only a weak effect on measured sLHR. Unadjusted and adjusted sLHR provide equivalent prognostic information for prediction of AMI or death.