Poststroke Care Pathways and Spasticity Treatment: A Retrospective Study in Alberta.

BACKGROUND: Limited evidence exists regarding care pathways for stroke survivors who do and do not receive poststroke spasticity (PSS) treatment. METHODS: Administrative data was used to identify adults who experienced a stroke and sought acute care between 2012 and 2017 in Alberta, Canada. Pathways of stroke care within the health care system were determined among those who initiated PSS treatment (PSS treatment group: outpatient pharmacy dispensation of an anti-spastic medication, focal chemo-denervation injection, or a spasticity tertiary clinic visit) and those who did not (non-PSS treatment group). Time from the stroke event until spasticity treatment initiation, and setting where treatment was initiated were reported. Descriptive statistics were performed. RESULTS: Health care settings within the pathways of stroke care that the PSS (n = 1,079) and non-PSS (n = 22,922) treatment groups encountered were the emergency department (86 and 84%), acute inpatient care (80 and 69%), inpatient rehabilitation (40 and 12%), and long-term care (19 and 13%), respectively. PSS treatment was initiated a median of 291 (interquartile range 625) days after the stroke event, and most often in the community when patients were residing at home (45%), followed by "other" settings (22%), inpatient rehabilitation (18%), long-term care (11%), and acute inpatient care (4%). CONCLUSIONS: To our knowledge, this is the first population based cohort study describing pathways of care among adults with stroke who subsequently did or did not initiate spasticity treatment. Areas for improvement in care may include strategies for earlier identification and treatment of PSS.

Geographical Variation In Medication and Health Resource Use In Multiple Sclerosis.

BACKGROUND: Understanding disease-modifying therapy (DMT) use and healthcare resource utilization by different geographical areas among people living with multiple sclerosis (pwMS) may identify care gaps that can be used to inform policies and practice to ensure equitable care. METHODS: Administrative data was used to identify pwMS on April 1, 2017 (index date) in Alberta. DMT use and healthcare resource utilization were compared between those who resided in various geographical areas over a 2-year post-index period; simple logistic regression was applied. RESULTS: Among the cohort (n = 12,338), a higher proportion of pwMS who resided in urban areas (versus rural) received ≥ 1 DMT dispensation (32.3% versus 27.4%), had a neurologist (67.7% versus 63.9%), non-neurologist specialist (88.3% versus 82.9%), ambulatory care visit (87.4% versus 85.3%), and MS tertiary clinic visit (59.2% versus 51.7%), and a lower proportion had an emergency department (ED) visit (46.3% versus 62.4%), and hospitalization (20.4% versus 23.0%). Across the provincial health zones, there were variations in DMT selection, and a higher proportion of pwMS who resided in the Calgary health zone, where care is managed by MS tertiary clinic neurologists, had an outpatient visit to a neurologist or MS tertiary clinic versus those who resided in other zones where delivery of MS-related care is more varied. CONCLUSIONS: Urban/rural inequalities in DMT use and healthcare resource utilization appear to exist among pwMS in Alberta. Findings suggest the exploration of barriers with consequent strategies to increase access to DMTs and provide timely outpatient MS care management, particularly for those pwMS residing in rural areas.

Benzodiazepine use in medical cannabis authorization adult patients from 2013 to 2021: Alberta, Canada.

BACKGROUND: Benzodiazepines are a class of medications that are being frequently prescribed in Canada but carry significant risk of harm. There has been increasing clinical interest on the potential "sparing effects" of medical cannabis as one strategy to reduce benzodiazepine use. The objective of this study as to examine the association of medical cannabis authorization with benzodiazepine usage between 2013 and 2021 in Alberta, Canada. METHODS: A propensity score matched cohort study with patients on regular benzodiazepine treatment authorized to use medical cannabis compared to controls who do not have authorization for medical cannabis. A total of 9690 medically authorized cannabis patients were matched to controls. To assess the effect of medical cannabis use on daily average diazepam equivalence (DDE), interrupted time series (ITS) analysis was used to assess the change in the trend of DDE in the 12 months before and 12 months after the authorization of medical cannabis. RESULTS: Over the follow-up period after medical cannabis authorization, there was no overall change in the DDE use in authorized medical cannabis patients compared to matched controls (- 0.08 DDE, 95% CI: - 0.41 to 0.24). Likewise, the sensitivity analysis showed that, among patients consuming ≤5 mg baseline DDE, there was no change immediately after medical cannabis authorization compared to controls (level change, - 0.04 DDE, 95% CI: - 0.12 to 0.03) per patient as well as in the month-to-month trend change (0.002 DDE, 95% CI: - 0.009 to 0.12) per patient was noted. CONCLUSIONS: This short-term study found that medical cannabis authorization had minimal effects on benzodiazepine use. Our findings may contribute ongoing evidence for clinicians regarding the potential impact of medical cannabis to reduce benzodiazepine use. HIGHLIGHTS: • Medical cannabis authorization had little to no effect on benzodiazepine usage among patients prescribed regular benzodiazepine treatment in Alberta, Canada. • Further clinical research is needed to investigate the potential impact of medical cannabis as an alternative to benzodiazepine medication.

Trajectory of health care resources among adults stopping or reducing treatment frequency of botulinum toxin for chronic migraine treatment in Alberta, Canada.

OBJECTIVE: Understand health resource, medication use, and cost of adults with chronic migraine who received guideline-recommended onabotulinumtoxinA (botulinum toxin) treatment frequency and then continued or reduced/stopped. BACKGROUND: Botulinum toxin may be a beneficial treatment for chronic migraine; the trajectory of health resources utilization among those with continued or reduced/stopped use is unclear. METHODS: A retrospective population-based cohort study utilizing administrative data from Alberta, Canada (2012-2020), was performed. A cohort of adults who received ≥5 botulinum toxin treatment cycles for chronic migraine over 18 months (6-month run-in; 1-year pre-index period) were grouped into those who (1) continued use (≥3 treatments/year), or (2) stopped or reduced use (stopped for 6 months then received 0 or 1-2 treatments/year, respectively) over a 1-year post-index period. Health resources and medication use were described, and pre-post costs were assessed. A second cohort that received ≥3 treatments/year immediately followed by 1 year of stopped or reduced use was considered in sensitivity analysis. RESULTS: Pre-post health resource, medication use, and costs were similar among those with continued use (n = 3336). Among those who stopped or reduced use (n = 1099; 756 stopped, 343 reduced), health resource, medication use, and costs were lower in the post- (total median per-person cost [IQR]: all-cause $4851 [$8090]; migraine-related $835 [$1915]) versus pre- (all-cause $6096 [$7207]; migraine-related $2995 [$1950]) index period (estimated cost ratios [95% CI]: total all-cause 0.86 [0.79, 0.95]; total migraine-related 0.44 [0.40, 0.48]). In the second cohort (n = 3763), return to continued use (≥3 treatments/year) occurred in up to 70.4% in those with reduced use. CONCLUSIONS: Of adults treated with botulinum toxin for chronic migraine, 75.2% had continued use, stable health resource and medication use, and costs over a 2 year period. In those that stopped/reduced use, the observed lower health resource and migraine medication use may indicate improved symptom control, but the resumption of guideline-recommended treatment intervals after reduced use was common.

Characteristics of Adults with Migraine in Alberta, Canada: A Population-Based Study.

BACKGROUND: Migraine, including episodic migraine (EM) and chronic migraine (CM), is a common neurological disorder that imparts a substantial health burden. OBJECTIVE: Understand the characteristics and treatment of EM and CM from a population-based perspective. METHODS: This retrospective population-based cross-sectional study utilized administrative data from Alberta. Among those with a migraine diagnostic code, CM and EM were identified by an algorithm and through exclusion, respectively; characteristics and migraine medication use were examined with descriptive statistics. RESULTS: From 79,076 adults with a migraine diagnostic code, 12,700 met the criteria for CM and 54,686 were considered to have EM. The majority of migraineurs were female, the most common comorbidity was depression, and individuals with CM had more comorbidities than EM. A larger proportion of individuals with CM versus EM were dispensed acute (80.6%: CM; 63.4%: EM) and preventative (58.0%: CM; 28.9%: EM) migraine medications over 1 year. Among those with a dispensation, individuals with CM had more acute (13.6 ± 32.2 vs. 4.6 ± 10.9 [mean ± standard deviation], 95% confidence interval [CI] 7.7-8.3), and preventative (12.6 ± 43.5 vs. 5.0 ± 12.6, 95% CI 6.9-8.4) migraine medication dispensations than EM, over 1-year. Opioids were commonly used in both groups (proportion of individuals dispensed an opioid over 1-year: 53.1%: CM; 25.7%: EM). CONCLUSIONS: Individuals with EM and CM displayed characteristics and medication use patterns consistent with other reports. Application of this algorithm for CM may be a useful and efficient means of identifying subgroups of migraine using routinely collected health data in Canada.

Health resource utilization and cost before versus after initiation of second-generation long-acting injectable antipsychotics among adults with schizophrenia in Alberta, Canada: a retrospective, observational single-arm study.

BACKGROUND: Long-acting injectable (LAI) antipsychotics, along with community treatment orders (CTOs), are used to improve treatment effectiveness through adherence among individuals with schizophrenia. Understanding real-world medication adherence, and healthcare resource utilization (HRU) and costs in individuals with schizophrenia overall and by CTO status before and after second generation antipsychotic (SGA)-LAI initiation may guide strategies to optimize treatment among those with schizophrenia. METHODS: This retrospective observational single-arm study utilized administrative health data from Alberta, Canada. Adults (≥ 18 years) with schizophrenia who initiated a SGA-LAI (no use in the previous 2-years) between April 1, 2014 and March 31, 2016, and had ≥ 1 additional dispensation of a SGA-LAI were included; index date was the date of SGA-LAI initiation. Medication possession ratio (MPR) was determined, and paired t-tests were used to examine mean differences in all-cause and mental health-related HRU and costs (Canadian dollars), comprised of hospitalizations, physician visits, emergency department visits, and total visits, over the 2-year post-index and 2-year pre-index periods. Analyses were stratified by presence or absence of an active CTO during the pre-index and/or post-index periods. RESULTS: Among 1,211 adults with schizophrenia who initiated SGA-LAIs, 64% were males with a mean age of 38 (standard deviation [SD] 14) years. The mean overall antipsychotic MPR was 0.39 (95% confidence interval [CI] 0.36, 0.41) greater during the 2-year post-index period (0.84 [SD 0.26]) compared with the 2-year pre-index period (0.45 [SD 0.40]). All-cause and mental health-related HRU and costs were lower post-index versus pre-index (p < 0.001) for hospitalizations, physician visits, emergency department visits, and total visits; mean total all-cause HRU costs were $33,788 (95% CI -$38,993, -$28,583) lower post- versus pre-index ($40,343 [SD $68,887] versus $74,131 [SD $75,941]), and total mental health-related HRU costs were $34,198 (95%CI -$39,098, -$29,297) lower post- versus pre-index ($34,205 [SD $63,428] versus $68,403 [SD $72,088]) per-patient. Forty-three percent had ≥ 1 active CTO during the study period; HRU and costs varied according to CTO status. CONCLUSIONS: SGA-LAIs are associated with greater medication adherence, and lower HRU and costs however the latter vary according to CTO status.

Effect of Clinical Decision Support With Audit and Feedback on Prevention of Acute Kidney Injury in Patients Undergoing Coronary Angiography: A Randomized Clinical Trial.

Importance: Contrast-associated acute kidney injury (AKI) is a common complication of coronary angiography and percutaneous coronary intervention (PCI) that has been associated with high costs and adverse long-term outcomes. Objective: To determine whether a multifaceted intervention is effective for the prevention of AKI after coronary angiography or PCI. Design, Setting, and Participants: A stepped-wedge, cluster randomized clinical trial was conducted in Alberta, Canada, that included all invasive cardiologists at 3 cardiac catheterization laboratories who were randomized to various start dates for the intervention between January 2018 and September 2019. Eligible patients were aged 18 years or older who underwent nonemergency coronary angiography, PCI, or both; who were not undergoing dialysis; and who had a predicted AKI risk of greater than 5%. Thirty-four physicians performed 7820 procedures among 7106 patients who met the inclusion criteria. Participant follow-up ended in November 2020. Interventions: During the intervention period, cardiologists received educational outreach, computerized clinical decision support on contrast volume and hemodynamic-guided intravenous fluid targets, and audit and feedback. During the control (preintervention) period, cardiologists provided usual care and did not receive the intervention. Main Outcomes and Measures: The primary outcome was AKI. There were 12 secondary outcomes, including contrast volume, intravenous fluid administration, and major adverse cardiovascular and kidney events. The analyses were conducted using time-adjusted models. Results: Of the 34 participating cardiologists who were divided into 8 clusters by practice group and center, the intervention group included 31 who performed 4327 procedures among 4032 patients (mean age, 70.3 [SD, 10.7] years; 1384 were women [32.0%]) and the control group included 34 who performed 3493 procedures among 3251 patients (mean age, 70.2 [SD, 10.8] years; 1151 were women [33.0%]). The incidence of AKI was 7.2% (310 events after 4327 procedures) during the intervention period and 8.6% (299 events after 3493 procedures) during the control period (between-group difference, -2.3% [95% CI, -0.6% to -4.1%]; odds ratio [OR], 0.72 [95% CI, 0.56 to 0.93]; P = .01). Of 12 prespecified secondary outcomes, 8 showed no significant difference. The proportion of procedures in which excessive contrast volumes were used was reduced to 38.1% during the intervention period from 51.7% during the control period (between-group difference, -12.0% [95% CI, -14.4% to -9.4%]; OR, 0.77 [95% CI, 0.65 to 0.90]; P = .002). The proportion of procedures in eligible patients in whom insufficient intravenous fluid was given was reduced to 60.8% during the intervention period from 75.1% during the control period (between-group difference, -15.8% [95% CI, -19.7% to -12.0%]; OR, 0.68 [95% CI, 0.53 to 0.87]; P = .002). There were no significant between-group differences in major adverse cardiovascular events or major adverse kidney events. Conclusions and Relevance: Among cardiologists randomized to an intervention including clinical decision support with audit and feedback, patients undergoing coronary procedures during the intervention period were less likely to develop AKI compared with those treated during the control period, with a time-adjusted absolute risk reduction of 2.3%. Whether this intervention would show efficacy outside this study setting requires further investigation. Trial Registration: ClinicalTrials.gov Identifier: NCT03453996.

Secular Changes in Mortality and Hospitalization over Time in People with Kidney Failure or Severe CKD as Compared with Other Noncommunicable Diseases.

BACKGROUND: Few new treatments have been developed for kidney failure or CKD in recent years, leading to perceptions of slower improvement in outcomes associated with CKD or kidney failure than for other major noncommunicable diseases. METHODS: Our retrospective cohort study included 548,609 people with an incident noncommunicable disease, including cardiovascular diseases, diabetes, various cancers, and severe CKD or kidney failure treated with renal replacement (KF-RRT), treated in Alberta, Canada, 2004-2015. For each disease, we assessed presence or absence of 8 comorbidities; we also compared secular trends in relative (compared to a referent year of 2004) and absolute risks of mortality and mean annual days in the hospital associated with each disease after 1 year and 5 years. RESULTS: Comorbidities increased significantly in number over time for all noncommunicable diseases except diabetes, and increased most rapidly for CKD and KF-RRT. Significant but relatively small reductions over time in the risk ratio of mortality at 1 year occurred for nearly all noncommunicable diseases. Secular trends in the absolute risk of mortality were similar; CKD and KF-RRT had a relatively favorable ranking at 1 year. Breast cancer, KF-RRT, diabetes, and colorectal cancer displayed the largest relative reductions in number of hospital days at 1 year. Significant absolute reductions in the number of hospital days were observed for both KF-RRT and CKD; the former had the highest absolute reduction among all noncommunicable diseases. Results were similar at 5 years. CONCLUSIONS: We observed secular reductions in mortality and annual hospital days at 1 year and 5 years among incident patients with KF-RRT and severe CKD, as well as several other common noncommunicable diseases.

Screening for Asymptomatic Coronary Artery Disease in Waitlisted Kidney Transplant Candidates: A Cost-Utility Analysis.

RATIONALE & OBJECTIVE: On account of the high prevalence of cardiovascular disease in patients with kidney failure, clinical practice guidelines recommend regular screening for asymptomatic coronary artery disease (CAD) in patients on the kidney transplant waitlist. To date, the cost-effectiveness of such screening has not been evaluated. A Canadian-Australasian randomized controlled trial of screening kidney transplant candidates for CAD (CARSK) is currently is being conducted to answer this question. We conducted a cost-utility analysis to determine, before completion of the trial, the cost-effectiveness of no further screening versus regular screening for asymptomatic CAD and to evaluate potential influential variables that may affect results of the economic evaluation. STUDY DESIGN: A modeled cost-utility analysis. SETTING & POPULATION: A theoretical cohort of adult Australian and New Zealand kidney transplant candidates on the waitlist. INTERVENTION: No further screening for asymptomatic CAD versus regular protocolized screening (annual or second yearly) for CAD after kidney transplant waitlisting. OUTCOMES: Incremental cost-effectiveness ratio, reported as cost per quality-adjusted life-year (QALY). MODEL, PERSPECTIVES, & TIMEFRAME: Markov microsimulation model, health system perspective and over a lifetime horizon. RESULTS: In the base case, the incremental cost-effectiveness ratio of no further screening was $11,122 per QALY gained when compared with regular screening. No further screening increased survival by 0.49 life-year or 0.35 QALY. One-way sensitivity analyses identified the costs of transplantation in the first year and CAD prevalence as the most influential variables. Probabilistic sensitivity analyses showed that 94% of the simulations were cost-effective below a willingness-to-pay threshold of $50,000 per QALY gained. LIMITATIONS: Rates of cardiovascular events in waitlisted candidates and transplant recipients are limited in the contemporary era. The results may not be generalizable to populations outside Australia and New Zealand. CONCLUSIONS: No further screening for CAD after waitlisting is likely to be cost-effective and may improve survival. Precision around CAD prevalence estimates and health care resource use will reduce existing uncertainty.

Canadian-Australasian Randomised trial of screening kidney transplant candidates for coronary artery disease-A trial protocol for the CARSK study.

Transplantation is the preferred treatment for patients with kidney failure, but the need exceeds the supply of transplantable kidneys, and patients routinely wait >5 years on dialysis for a transplant. Coronary artery disease (CAD) is common in kidney failure and can exclude patients from transplantation or result in death before or after transplantation. Screening asymptomatic patients for CAD using noninvasive tests prior to wait-listing and at regular intervals (ie, annually) after wait-listing until transplantation is the established standard of care and is justified by the need to avoid adverse patient outcomes and loss of organs. Patients with abnormal screening tests undergo coronary angiography, and those with critical stenoses are revascularized. Screening is potentially harmful because patients may be excluded or delayed from transplantation, and complications after revascularization are more frequent in this population. CARSK will test the hypothesis that eliminating screening tests for occult CAD after wait-listing is not inferior to regular screening for the prevention of major adverse cardiac events defined as the composite of cardiovascular death, nonfatal myocardial infarction, urgent revascularization, and hospitalization for unstable angina. Secondary outcomes include the transplant rate, safety measures, and the cost-effectiveness of screening. Enrolment of 3,306 patients over 3 years is required, with patients followed for up to 5 years during wait-listing and for 1 year after transplantation. By validating or refuting the use of screening tests during wait-listing, CARSK will ensure judicious use of health resources and optimal patient outcomes.

A Cost Analysis and Cost-Utility Analysis of a Community Pharmacist-Led Intervention on Reducing Cardiovascular Risk: The Alberta Vascular Risk Reduction Community Pharmacy Project (RxEACH).

BACKGROUND: A randomized trial (the Alberta Vascular Risk Reduction Community Pharmacy Project) showed that a community pharmacist-led intervention was efficacious for reducing cardiovascular (CV) risk. However, the cost of this strategy is unknown. OBJECTIVES: We examined the short- and long-term cost of a pharmacist-led intervention to reduce CV risk compared to usual care. METHODS: We conducted a trial-based cost analysis from the perspective of a publicly funded healthcare system. Over 3 and 12 months of follow-up, we examined specific intervention costs (pharmacy claims), related intervention costs (laboratory tests and medications), and ongoing healthcare costs (physician claims, emergency department visits, and hospital admissions). We also used the validated CV Disease Policy Model-Canada to estimate the long-term effects. RESULTS: A total of 684 participants (mean age 62, 57% male) were included. Overall, there were no significant differences in healthcare costs at 3 or 12 months between the usual care and intervention groups (P = .127). The CV disease-related healthcare cost of managing a patient over a lifetime was estimated to be Can$45 530 (95% uncertainty interval [UI], 45 460-45 580) and Can$40 750 (95% UI, 37 780-43 620) in usual care and intervention groups, respectively, an incremental cost savings of Can$4770 per patient (95% UI, 1900-7760). The intervention dominated usual care (better outcomes and lower costs) across 3-year, 5-year, 10-year, and lifetime horizons. CONCLUSION: This economic analysis suggests that a clinical pathway-driven pharmacist-led intervention (previously shown to reduce CV risk) was associated with similar measured healthcare costs over 1 year, and lower extrapolated healthcare costs over a patient lifetime. This strategy could be broadly implemented to realize its benefits.

Joint associations of obesity and estimated GFR with clinical outcomes: a population-based cohort study.

BACKGROUND: Despite the interrelationships between obesity, eGFR and albuminuria, few large studies examine how obesity modifies the association between these markers of kidney function and adverse clinical outcomes. METHODS: We examined the joint associations between obesity, eGFR and albuminuria on four clinical outcomes (death, end-stage renal disease [ESRD], myocardial infarction [MI], and placement in a long-term care facility) using a population-based cohort with procedures from Alberta. Obesity was defined by body mass index ≥35 kg/m2 as defined by a fee modifier applied to an eligible procedure. RESULTS: We studied 1,293,362 participants, of whom 171,650 (13.3%) had documented obesity (BMI ≥ 35 kg/m2 based on claims data) and 1,121,712 (86.7%) did not. The association between eGFR and death was J-shaped for participants with and without documented obesity. After full adjustment, obesity tended to be associated with slightly lower odds of mortality (OR range 0.71-1.02; p for interaction between obesity and eGFR 0.008). For participants with and without obesity, the adjusted odds of ESRD were lowest for participants with eGFR > 90 mL/min*1.73m2 and increased with lower eGFR, with no evidence of an interaction with obesity (p = 0.37). Although albuminuria and obesity were both associated with higher odds of ESRD, the excess risk associated with obesity was substantially attenuated at higher levels of albuminuria (p for interaction 0.0006). The excess risk of MI associated with obesity was observed at eGFR > 60 mL/min*1.73m2 but not at lower eGFR (p for interaction < 0.0001). Participants with obesity had a higher adjusted likelihood of placement in long-term care than those without, and the likelihood of such placement was higher at lower eGFR for those with and without obesity (p for interaction = 0.57). CONCLUSIONS: We found significant interactions between obesity and eGFR and/or albuminuria on the likelihood of adverse outcomes including death and ESRD. Since obesity is common, risk prediction tools for people with CKD might be improved by adding information on BMI or other proxies for body size in addition to eGFR and albuminuria.

Statin use and the risk of acute kidney injury in older adults.

BACKGROUND: As more patients at lower cardiovascular (CV) risk are treated with statins, the balance between cardiovascular benefits and the risk of adverse events becomes increasingly important. METHODS: We did a population-based cohort study (May 1, 2002 to March 30, 2013) using province-wide laboratory and administrative data in Alberta. We studied new statin users aged 66 years of age and older who were not receiving renal replacement therapy at baseline. We assessed statin use at 30-day intervals to allow time-varying assessment of statin exposure in Cox proportional hazards models that examined the relation between statin use and hospitalization with acute kidney injury (AKI). RESULTS: Of the 128,140 new statin users, 47 and 46% were prescribed high- and medium-intensity regimens at the index date. During median follow-up of 4.6 years (interquartile range 2.2, 7.4), 9118 individuals were hospitalized for AKI. Compared to non-use, the use of high- and medium-intensity statin regimens was associated with significant increases in the adjusted risks of hospitalization with AKI: hazard ratios 1.16 [95% confidence interval (CI) 1.10, 1.23] and 1.07 (95% CI 1.01, 1.13), respectively. Risks of AKI were higher among women than men, and among users of angiotensin converting enzyme inhibitors/angiotensin receptor blockers than non-users, and among diuretic users (p for interaction 0.002, 0.01, and 0.04 respectively). CONCLUSIONS: We found a graded, independent association between the intensity of statin use and the risk of hospitalization with AKI, although the absolute magnitude of the excess risk was small.

Correction to: Methods for identifying 30 chronic conditions: application to administrative data.

Following publication of the original manuscript [1], the authors noted several errors in Table 1. Details of the requested corrections are shown below.

A population-based cohort study defines prognoses in severe chronic kidney disease.

In older people with chronic kidney disease (CKD) and comorbidities, the risk of death or disability may overshadow the risk of kidney failure. To help refine this we did a retrospective population-based cohort study to evaluate the relative likelihood of adverse outcomes as functions of age and comorbidity burden among 47,228 adults with severe non-dialysis dependent CKD. We identified comorbidities using 29 validated algorithms applied to administrative data and assessed death, end-stage renal disease (ESRD), cardiovascular disease (CVD) events, and long-term care. Over five years of follow-up, 53.4% of participants died, 24.1% had a CVD event, 14.3% were placed into long-term care and 5.3% developed ESRD. Death was 145 times more likely and 11 times more likely than ESRD for participants aged 80 years or more and 60-79 years, respectively; long-term care was 30 times more likely and 1.7 times as likely as ESRD for participants aged 80 years or more and 60-79 years, respectively. Increasing comorbidity burden was similarly associated with increased risk of death and long-term care placement but reduced the likelihood of ESRD, and the risks of increasing age were similarly incremental. Thus, among patients with severe CKD, older age and/or higher comorbidity burden, death and long-term care placement are markedly more likely than ESRD. Hence, clinicians, patients and families should all consider the relative magnitude of these risks when making decisions about renal replacement.

Concentrations of Trace Elements in Hemodialysis Patients: A Prospective Cohort Study.

BACKGROUND: Low concentrations and excessive concentrations of trace elements have been commonly reported in hemodialysis patients, but available studies have several important limitations. STUDY DESIGN: Random sample of patients drawn from a prospective cohort. SETTING & PARTICIPANTS: 198 incident hemodialysis patients treated in 3 Canadian centers. MEASUREMENTS: We used mass spectrometry to measure plasma concentrations of the 25 elements at baseline, 6 months, 1 year, and 2 years following enrollment in the cohort. We focused on low concentrations of zinc, selenium, and manganese and excessive concentrations of lead, arsenic, and mercury; low and excessive concentrations of the other 19 trace elements were treated as exploratory analyses. Low and excessive concentrations were based on the 5th and 95th percentile plasma concentrations from healthy reference populations. RESULTS: At all 4 occasions, low zinc, selenium, and manganese concentrations were uncommon in study participants (≤5.1%, ≤1.8%, and ≤0.9% for zinc, selenium, and manganese, respectively) and a substantial proportion of participants had concentrations that exceeded the 95th percentile (≥65.2%, ≥74.2%, and ≥19.7%, respectively). Almost all participants had plasma lead concentrations above the 95th percentile at all time points. The proportion of participants with plasma arsenic concentrations exceeding the 95th percentile was relatively constant over time (9.1%-9.8%); the proportion with plasma mercury concentrations that exceeded the 95th percentile varied between 15.2% and 29.3%. Low arsenic, platinum, tungsten, and beryllium concentrations were common (>50%), as were excessive cobalt, manganese, zinc, vanadium, cadmium, selenium, barium, antimony, nickel, molybdenum, lead, and chromium concentrations. CONCLUSIONS: There was no evidence that low zinc, selenium, or manganese concentrations exist in most contemporary Canadian hemodialysis patients. Some patients have excessive plasma arsenic and mercury concentrations, and excessive lead concentrations were common. These findings require further investigation.

Association of Preference-Based Health-Related Quality of Life with Weight Loss in Obese Adults.

BACKGROUND: The obesity epidemic is linked to substantial health care resource use, reduction in workforce and home productivity, and poor health-related quality of life (HRQOL). Changes in body mass index (BMI) are associated with improvements in HRQOL; the nature of this relationship, however, has not been reliably described. OBJECTIVES: To determine the independent association between changes in BMI and change in utility-based HRQOL. METHODS: Data were prospectively collected on 500 severely obese adult patients enrolled in a single-center obesity management clinic. Univariable and multivariable linear regressions were performed, adjusting for the effect of the intervention itself, obesity-related comorbidities, BMI at enrollment, age, and sex. RESULTS: A 1-unit reduction in BMI was associated with a 0.0075 (95% confidence interval 0.0041-0.0109) increase in the EuroQol five-dimensional questionnaire score. This relationship was unaltered in various analyses, and is likely applicable to any health-care-induced changes in BMI. CONCLUSIONS: The quantification of this association advances the understanding of the clinical benefits of interventions that affect BMI, and can inform more robust cost-utility analyses.

A Systematic Review of the Cost-Effectiveness of Long-Term Mechanical Circulatory Support.

BACKGROUND: Mechanical circulatory support (MCS) is an option for the treatment of medically intractable end-stage heart failure. MCS therapy, however, is resource intensive. OBJECTIVE: The purpose of this report was to systematically review the MCS cost-effectiveness literature as it pertains to the treatment of adult patients in end-stage heart failure. METHODS: We conducted a systematic search and narrative review of available cost- effectiveness and cost-utility analyses of MCS in adult patients with end-stage heart failure. RESULTS: Eleven studies analyzing the cost-effectiveness or cost-utility of MCS were identified. Seven studies focused on bridge to transplantation, three studies focused on destination therapy, and one study presented analyses of both strategies. Two articles evaluated the cost-effectiveness of the HeartMate II (Thoratec Corp., Pleasanton, CA). Incremental cost-effectiveness ratios between MCS and medical management ranged between $85,025 and $200,166 for bridge to transplantation and between $87,622 and $1,257,946 for destination therapy (2012 Canadian dollars per quality-adjusted life-year). Sensitivity analyses indicated that improvements in survival and quality of life and reductions in device and initial hospital-stay costs may improve the cost-effectiveness of MCS. CONCLUSIONS: Current studies suggest that MCS is likely not cost-effective with reference to generally accepted or explicitly stated thresholds. Refined patient selection, complication rates, achieved quality of life, and device/surgical costs, however, could modify the cost-effectiveness of MCS.

Comorbidity as a driver of adverse outcomes in people with chronic kidney disease.

Chronic kidney disease (CKD) is associated with poor outcomes, perhaps due to a high burden of comorbidity. Most studies of CKD populations focus on concordant comorbidities, which cause CKD (such as hypertension and diabetes) or often accompany CKD (such as heart failure or coronary disease). Less is known about the burden of mental health conditions and discordant conditions (those not concordant but still clinically relevant, like dementia or cancer). Here we did a retrospective population-based cohort study of 530,771 adults with CKD residing in Alberta, Canada between 2003 and 2011. Validated algorithms were applied to data from the provincial health ministry to assess the presence/absence of 29 chronic comorbidities. Linkage between comorbidity burden and adverse clinical outcomes (mortality, hospitalization or myocardial infarction) was examined over median follow-up of 48 months. Comorbidities were classified into three categories: concordant, mental health/chronic pain, and discordant. The median number of comorbidities was 1 (range 0-15) but a substantial proportion of participants had 3 and more, or 5 and more comorbidities (25 and 7%, respectively). Concordant comorbidities were associated with excess risk of hospitalization, but so were discordant comorbidities and mental health conditions. Thus, discordant comorbidities and mental health conditions as well as concordant comorbidities are important independent drivers of the adverse outcomes associated with CKD.

Relocation of remote dwellers living with hemodialysis: a time trade-off survey.

BACKGROUND: There has been little research exploring the experience of dialysis therapy for people living in remote communities. Remote residence location has previously been associated with excess mortality in hemodialysis (HD) patients, suggesting that relocation to a referral center might improve outcomes. It is unknown whether patients view this approach as acceptable. METHODS: We studied 121 remote-dwelling chronic HD patients using the time trade-off method applied to hypothetical scenarios. RESULTS: Participants indicated that they would trade a median of 6 years of life in their current location (including current social supports) (95% CI 2.25-7) for 10 years of life in a referral center without any of their existing social supports (meaning they would be willing to forgo 4 years of life to remain in their current residence location). When current social supports were assumed to continue in both locations, people were only willing to forego a median of 2 years of life (95% CI 1-4) to remain in their current location. Older participants were much less willing to accept relocation than younger participants; the median time trade-off associated with relocation and without social supports was 2 years for participants aged <50 years, 3 years for those aged 50-69.9 years and 9 years for those aged ≥70 years. CONCLUSIONS: Hemodialysis patients currently living remotely were willing to forgo much of their remaining life expectancy rather than relocate-especially among older participants. These findings suggest that decisions about relocation should be accompanied by discussion of anticipated changes in quality of life and life expectancy.