Hypertension and Kidney Function After Living Kidney Donation.

Importance: Recent guidelines call for better evidence on health outcomes after living kidney donation. Objective: To determine the risk of hypertension in normotensive adults who donated a kidney compared with nondonors of similar baseline health. Their rates of estimated glomerular filtration rate (eGFR) decline and risk of albuminuria were also compared. Design, Setting, and Participants: Prospective cohort study of 924 standard-criteria living kidney donors enrolled before surgery and a concurrent sample of 396 nondonors. Recruitment occurred from 2004 to 2014 from 17 transplant centers (12 in Canada and 5 in Australia); follow-up occurred until November 2021. Donors and nondonors had the same annual schedule of follow-up assessments. Inverse probability of treatment weighting on a propensity score was used to balance donors and nondonors on baseline characteristics. Exposure: Living kidney donation. Main Outcomes and Measures: Hypertension (systolic blood pressure [SBP] ≥140 mm Hg, diastolic blood pressure [DBP] ≥90 mm Hg, or antihypertensive medication), annualized change in eGFR (starting 12 months after donation/simulated donation date in nondonors), and albuminuria (albumin to creatinine ratio ≥3 mg/mmol [≥30 mg/g]). Results: Among the 924 donors, 66% were female; they had a mean age of 47 years and a mean eGFR of 100 mL/min/1.73 m2. Donors were more likely than nondonors to have a family history of kidney failure (464/922 [50%] vs 89/394 [23%], respectively). After statistical weighting, the sample of nondonors increased to 928 and baseline characteristics were similar between the 2 groups. During a median follow-up of 7.3 years (IQR, 6.0-9.0), in weighted analysis, hypertension occurred in 161 of 924 donors (17%) and 158 of 928 nondonors (17%) (weighted hazard ratio, 1.11 [95% CI, 0.75-1.66]). The longitudinal change in mean blood pressure was similar in donors and nondonors. After the initial drop in donors' eGFR after nephrectomy (mean, 32 mL/min/1.73 m2), donors had a 1.4-mL/min/1.73 m2 (95% CI, 1.2-1.5) per year lesser decline in eGFR than nondonors. However, more donors than nondonors had an eGFR between 30 and 60 mL/min/1.73 m2 at least once in follow-up (438/924 [47%] vs 49/928 [5%]). Albuminuria occurred in 132 of 905 donors (15%) and 95 of 904 nondonors (11%) (weighted hazard ratio, 1.46 [95% CI, 0.97-2.21]); the weighted between-group difference in the albumin to creatinine ratio was 1.02 (95% CI, 0.88-1.19). Conclusions and Relevance: In this cohort study of living kidney donors and nondonors with the same follow-up schedule, the risks of hypertension and albuminuria were not significantly different. After the initial drop in eGFR from nephrectomy, donors had a slower mean rate of eGFR decline than nondonors but were more likely to have an eGFR between 30 and 60 mL/min/1.73 m2 at least once in follow-up. Trial Registration: ClinicalTrials.gov Identifier: NCT00936078.

The effect of micro-particle curcumin on chronic kidney disease progression: the MPAC-CKD randomized clinical trial.

BACKGROUND: Curcumin is a commonly used herbal supplement with anti-inflammatory and anti-fibrotic properties. Animal studies and small human trials suggest that curcumin reduces albuminuria in patients with chronic kidney disease (CKD). Micro-particle curcumin is a new, more bioavailable formulation of curcumin. METHODS: To determine whether micro-particle curcumin versus placebo slows the progression of albuminuric CKD we conducted a randomized, double-blind, placebo-controlled trial with 6-month follow-up. We included adults with albuminuria [a random urine albumin-to-creatinine ratio >30 mg/mmol (265 mg/g) or a 24-h urine collection with more than 300 mg of protein] and an estimated glomerular filtration rate (eGFR) between 15 and 60 mL/min/1.73 m2 within the 3 months before randomization. We randomly allocated participants 1:1 to receive micro-particle curcumin capsules (90 mg/day) or matching placebo for 6 months. After randomization, the co-primary outcomes were the changes in albuminuria and the eGFR. RESULTS: We enrolled 533 participants, but 4/265 participants in the curcumin group and 15/268 in the placebo group withdrew consent or became ineligible. The 6-month change in albuminuria did not differ significantly between the curcumin and placebo groups [geometric mean ratio 0.94, 97.5% confidence interval (CI) 0.82 to 1.08, P = .32]. Similarly, the 6-month change in eGFR did not differ between groups (mean between-group difference -0.22 mL/min/1.73 m2, 97.5% CI -1.38 to 0.95, P = .68). CONCLUSIONS: Ninety milligrams of micro-particle curcumin daily did not slow the progression of albuminuric CKD over 6 months. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02369549.

Trimethoprim-sulfamethoxazole and the risk of a hospital encounter with hyperkalemia: a matched population-based cohort study.

BACKGROUND: Trimethoprim-sulfamethoxazole (TMP-SMX) can cause hyperkalemia by reducing renal potassium excretion. We assessed the risk of hyperkalemia after initiating TMP-SMX versus amoxicillin and determined if this risk is modified by a patient's baseline kidney function [estimated glomerular filtration rate (eGFR)]. METHODS: We conducted a population-based cohort study in Ontario, Canada involving adults ≥66 years of age newly treated with TMP-SMX (n = 58 999) matched 1:1 with those newly treated with amoxicillin (2008-2020). The primary outcome was a hospital encounter with hyperkalemia defined by a laboratory serum potassium value ≥5.5 mmol/L within 14 days of antibiotic treatment. Secondary outcomes included a hospital encounter with acute kidney injury (AKI) and all-cause hospitalization. Risk ratios (RRs) were obtained using a modified Poisson regression. RESULTS: A hospital encounter with hyperkalemia occurred in 269/58 999 (0.46%) patients treated with TMP-SMX versus 80/58 999 (0.14%) in those treated with amoxicillin {RR 3.36 [95% confidence interval (CI) 2.62-4.31]}. The absolute risk of hyperkalemia in patients treated with TMP-SMX versus amoxicillin increased progressively with decreasing eGFR (risk difference of 0.12% for an eGFR ≥60 ml/min/1.73 m2, 0.42% for eGFR 45-59, 0.85% for eGFR 30-44 and 1.45% for eGFR <30; additive interaction P < .001). TMP-SMX versus amoxicillin was associated with a higher risk of a hospital encounter with AKI [RR 3.15 (95% CI 2.82-3.51)] and all-cause hospitalization [RR 1.43 (95% CI 1.34-1.53)]. CONCLUSIONS: The 14-day risk of a hospital encounter with hyperkalemia was higher in patients newly treated with TMP-SMX versus amoxicillin and the risk was highest in patients with a low eGFR.

Higher-Dose Gabapentinoids and the Risk of Adverse Events in Older Adults With CKD: A Population-Based Cohort Study.

RATIONALE & OBJECTIVE: Gabapentinoids are opioid substitutes whose elimination by the kidneys is reduced as kidney function declines. To inform their safe prescribing in older adults with chronic kidney disease (CKD), we examined the 30-day risk of serious adverse events according to the prescribed starting dose. STUDY DESIGN: Population-based cohort study. SETTING & PARTICIPANTS: 74,084 older adults (64% women; median age, 79 [interquartile range, 73-85] years) with CKD (defined for this study as an estimated glomerular filtration rate <60 mL/min/1.73 m2 and excluding those receiving dialysis) and a newly prescribed gabapentinoid between 2008 and 2020 in Ontario, Canada. EXPOSURE: Higher-dose gabapentinoids (gabapentin >300 mg/d or pregabalin >75 mg/d) versus lower-dose gabapentinoids (gabapentin ≤300 mg/d or pregabalin ≤75 mg/d). OUTCOMES: The primary composite outcome was the 30-day risk of a hospital visit with encephalopathy, a fall, or a fracture or a hospitalization with respiratory depression. ANALYTICAL APPROACH: Comparison groups were balanced on indicators of baseline health using inverse probability of treatment weighting using propensity score analysis that generated a pseudosample for the reference group with a distribution of measured covariates similar to the exposed group. Weighted risk ratios were estimated using modified Poisson regression, and weighted risk differences were estimated using binomial regression. Prespecified subgroup analyses were conducted by estimated glomerular filtration rate category and type of gabapentinoid. RESULTS: Among 74,084 patients identified with CKD and a new prescription for gabapentin or pregabalin, 41% started at >300 or >75 mg/d, respectively. From this set of patients, a weighted study population with a size of 61,367 was generated. Patients who started at a higher dose had a higher 30-day risk of the primary outcome than patients who started at lower dose. Within the weighted population, the numbers of events for higher versus lower dose were 585 of 30,660 (1.9%) versus 462 of 30,707 (1.5%), respectively. The weighted risk ratio was 1.27 (95% CI, 1.13-1.42), and the weighted risk difference was 0.40% (95% CI, 0.21%-0.60%). In subgroup analyses, neither multiplicative nor additive interactions were statistically significant. LIMITATIONS: Residual confounding. CONCLUSIONS: In this population-based study, starting a gabapentinoid at a higher versus a lower dose was associated with a slightly higher risk of a hospital visit with encephalopathy, a fall, or a fracture or hospitalization with respiratory depression. If verified, these risks should be balanced against the benefits of using a higher-dose gabapentinoid.

Initiation Dose of Allopurinol and the Risk of Severe Cutaneous Reactions in Older Adults With CKD: A Population-Based Cohort Study.

RATIONALE & OBJECTIVE: Allopurinol should be started at lower doses in patients with chronic kidney disease (CKD) to avoid adverse effects. We examined the risk of severe cutaneous reactions in older adults with CKD who were newly prescribed allopurinol at varied doses. STUDY DESIGN: Population-based cohort study using linked health care databases. SETTING & PARTICIPANTS: Patients in Ontario, Canada (2008-2019) aged ≥66 years, with an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2, and who were new users of allopurinol. EXPOSURE: A new prescription for allopurinol >100 mg/d versus a dose ≤100 mg/d. OUTCOME: The primary outcome was a hospital visit with a severe cutaneous reaction within 180 days of starting allopurinol. Secondary outcomes included all-cause hospitalization and all-cause mortality. ANALYTICAL APPROACH: The exposure and referent groups were balanced on indicators of baseline health using inverse probability of treatment weighting on the propensity score. Weighted risk ratios (RR) were obtained using modified Poisson regression and weighted risk differences (RD) using binomial regression. RESULTS: Of 47,315 patients (median age, 76 years; median eGFR, 45 mL/min/1.73 m2), 55% started allopurinol at >100 mg/d. Starting allopurinol at >100 versus ≤100 mg/d was associated with an increased risk of a severe cutaneous reaction: number of events (weighted), 103 of 25,802 (0.40%) versus 46 of 25,816 (0.18%), respectively (weighted RR, 2.25 [95% CI, 1.50-3.37]; weighted RD, 0.22% [95% CI, 0.12%-0.32%]. Starting allopurinol at >100 versus ≤100 mg/d was associated with an increased risk of all-cause hospitalization but not with all-cause mortality. LIMITATIONS: This study was underpowered to detect risk differences in the association of allopurinol dose with outcomes across eGFR categories (ie, 45-59, 30-44, and <30 mL/min/1.73 m2). CONCLUSIONS: Older patients with CKD who started allopurinol at >100 mg/d versus ≤100 mg/d were twice as likely to visit a hospital with a severe cutaneous reaction in the next 180 days.

Partnering with Patients to Enhance Access to Kidney Transplantation and Living Kidney Donation.

Kidney transplantation gives many patients with kidney failure a longer and healthier life. Unfortunately, some transplant-eligible patients will never receive one. In this paper, we describe how patients and researchers collaborated on new strategies and programs to enhance access to kidney transplantation and living kidney donation. These efforts led to the creation of the Transplant Ambassador Program (TAP). TAP is a patient-led program that helps connect patients who have kidney failure to individuals who have successfully received a kidney transplant or donated a kidney. We also detail barriers, facilitators and lessons learned from engaging patients in research.

Uptake of Colorectal Cancer Screening by Physicians Is Associated With Greater Uptake by Their Patients.

BACKGROUND & AIMS: Physicians' own screening practices might affect screening in their patients. We conducted a population-based study to evaluate whether family physicians who underwent colorectal cancer testing were more likely to have patients who underwent colorectal cancer testing. METHODS: We collected demographic and health care information on residents of Ontario, Canada from administrative databases; the sample was restricted to individuals at average risk of colorectal cancer who were 52-74 years old as of April 21, 2016. We obtained a list of all registered physicians in the province; physicians (n = 11,434) were matched with nonphysicians (n = 45,736) on age, sex, and residential location. Uptake of colorectal tests was defined by a record of a fecal occult blood test in the past 2 years, flexible sigmoidoscopy in the past 5 years, or colonoscopy in the past 10 years. Patients were assigned to family physicians based on billing claim frequency, and then the association between colorectal testing in family physicians and their patients was examined using a modified Poisson regression model. RESULTS: Uptake of colorectal tests by physicians and nonphysicians (median age 60 years; 71% men) was 67.9% (95% confidence interval [CI], 67.0%-68.7%) and 66.6% (95% CI, 66.2%-67.1%), respectively. Physicians were less likely than nonphysicians to undergo fecal occult blood testing and were more likely to undergo colonoscopy; prevalence ratios were 0.44 (95% CI, 0.42-0.47) and 1.24 (95% CI, 1.22-1.26), respectively. Uptake of colorectal tests by family physicians was associated with greater uptake by their patients (adjusted prevalence ratio, 1.10; 95% CI, 1.08-1.12). CONCLUSIONS: Approximately one-third of physicians and nonphysicians are overdue for colorectal cancer screening. Patients are more likely to be tested if their family physician has been tested. There is an opportunity for physicians to increase their participation in colorectal cancer screening, which could, in turn, motivate their patients to undergo screening.

Baclofen has a risk of encephalopathy in older adults receiving dialysis.

At least 23 case reports link the muscle relaxant baclofen to encephalopathy in patients receiving dialysis. To explore this issue, we conducted a study to quantify the risk of encephalopathy from baclofen in patients receiving dialysis. Linked healthcare databases were used to conduct a population-based cohort study of older adults receiving maintenance dialysis in Ontario, Canada (1997-2018) to compare new users of baclofen to non-users. The primary outcome was the 30-day risk of hospitalization with encephalopathy, defined as a main diagnosis of delirium, disorientation, transient alteration of awareness, or transient cerebral ischemic attack. Inverse probability of treatment weighting on the propensity score was used to balance comparison groups on indicators of baseline health. Weighted risk ratios (RR) were obtained using modified Poisson regression and weighted risk differences (RD) using binomial regression. We studied 360 new baclofen users and 6109 non-users (2638 [41%] women; median age 75). The median baclofen dose was 20 mg/day. Hospitalization with encephalopathy occurred in 26 of 360 baclofen users (7.2%) and in under six of 6109 non-users (under 0.1%); weighted risk ratios, 78.3 (95% confidence interval 27.9 to 219.2); weighted risk differences, 7.1% (4.5% to 9.8%). The median time from baclofen dispensing to hospitalization with encephalopathy was three days. Among patients receiving dialysis, approximately one in 14 were hospitalized with encephalopathy shortly after starting baclofen. Thus, baclofen should be avoided in older adults receiving dialysis, and other muscle relaxants considered in its place. Hence, if baclofen must be used, a low dose should be prescribed, and older adults should be carefully monitored for signs of encephalopathy.

Safety of a Restrictive versus Liberal Approach to Red Blood Cell Transfusion on the Outcome of AKI in Patients Undergoing Cardiac Surgery: A Randomized Clinical Trial.

BACKGROUND: Safely reducing red blood cell transfusions can prevent transfusion-related adverse effects, conserve the blood supply, and reduce health care costs. Both anemia and red blood cell transfusion are independently associated with AKI, but observational data are insufficient to determine whether a restrictive approach to transfusion can be used without increasing AKI risk. METHODS: In a prespecified kidney substudy of a randomized noninferiority trial, we compared a restrictive threshold for red blood cell transfusion (transfuse if hemoglobin<7.5 g/dl, intraoperatively and postoperatively) with a liberal threshold (transfuse if hemoglobin<9.5 g/dl in the operating room or intensive care unit, or if hemoglobin<8.5 g/dl on the nonintensive care ward). We studied 4531 patients undergoing cardiac surgery with cardiopulmonary bypass who had a moderate-to-high risk of perioperative death. The substudy's primary outcome was AKI, defined as a postoperative increase in serum creatinine of ≥0.3 mg/dl within 48 hours of surgery, or ≥50% within 7 days of surgery. RESULTS: Patients in the restrictive-threshold group received significantly fewer transfusions than patients in the liberal-threshold group (1.8 versus 2.9 on average, or 38% fewer transfusions in the restricted-threshold group compared with the liberal-threshold group; P<0.001). AKI occurred in 27.7% of patients in the restrictive-threshold group (624 of 2251) and in 27.9% of patients in the liberal-threshold group (636 of 2280). Similarly, among patients with preoperative CKD, AKI occurred in 33.6% of patients in the restrictive-threshold group (258 of 767) and in 32.5% of patients in the liberal-threshold group (252 of 775). CONCLUSIONS: Among patients undergoing cardiac surgery, a restrictive transfusion approach resulted in fewer red blood cell transfusions without increasing the risk of AKI.

Effect of methylprednisolone on acute kidney injury in patients undergoing cardiac surgery with a cardiopulmonary bypass pump: a randomized controlled trial.

BACKGROUND: Perioperative corticosteroid use may reduce acute kidney injury. We sought to test whether methylprednisolone reduces the risk of acute kidney injury after cardiac surgery. METHODS: We conducted a prespecified substudy of a randomized controlled trial involving patients undergoing cardiac surgery with cardiopulmonary bypass (2007-2014); patients were recruited from 79 centres in 18 countries. Eligibility criteria included a moderate-to-high risk of perioperative death based on a preoperative score of 6 or greater on the European System for Cardiac Operative Risk Evaluation I. Patients (n = 7286) were randomly assigned (1:1) to receive intravenous methylprednisolone (250 mg at anesthetic induction and 250 mg at initiation of cardiopulmonary bypass) or placebo. Patients, caregivers, data collectors and outcome adjudicators were unaware of the assigned intervention. The primary outcome was postoperative acute kidney injury, defined as an increase in the serum creatinine concentration (from the preoperative value) of 0.3 mg/dL or greater (≥ 26.5 µmol/L) or 50% or greater in the 14-day period after surgery, or use of dialysis within 30 days after surgery. RESULTS: Acute kidney injury occurred in 1479/3647 patients (40.6%) in the methylprednisolone group and in 1426/3639 patients (39.2%) in the placebo group (adjusted relative risk 1.04, 95% confidence interval 0.96 to 1.11). Results were consistent across several definitions of acute kidney injury and in patients with preoperative chronic kidney disease. INTERPRETATION: Intraoperative corticosteroid use did not reduce the risk of acute kidney injury in patients with a moderate-to-high risk of perioperative death who had cardiac surgery with cardiopulmonary bypass. Our results do not support the prophylactic use of steroids during cardiopulmonary bypass surgery. Trial registration: ClinicalTrials.gov, no. NCT00427388.

Financial Costs Incurred by Living Kidney Donors: A Prospective Cohort Study.

BACKGROUND: Approximately 40% of the kidneys for transplant worldwide come from living donors. Despite advantages of living donor transplants, rates have stagnated in recent years. One possible barrier may be costs related to the transplant process that potential willing donors may incur for travel, parking, accommodation, and lost productivity. METHODS: To better understand and quantify the financial costs incurred by living kidney donors, we conducted a prospective cohort study, recruiting 912 living kidney donors from 12 transplant centers across Canada between 2009 and 2014; 821 of them completed all or a portion of the costing survey. We report microcosted total, out-of-pocket, and lost productivity costs (in 2016 Canadian dollars) for living kidney donors from donor evaluation start to 3 months after donation. We examined costs according to (1) the donor's relationship with their recipient, including spousal (donation to a partner), emotionally related nonspousal (friend, step-parent, in law), or genetically related; and (2) donation type (directed, paired kidney, or nondirected). RESULTS: Living kidney donors incurred a median (75th percentile) of $1254 ($2589) in out-of-pocket costs and $0 ($1908) in lost productivity costs. On average, total costs were $2226 higher in spousal compared with emotionally related nonspousal donors (P=0.02) and $1664 higher in directed donors compared with nondirected donors (P<0.001). Total costs (out-of-pocket and lost productivity) exceeded $5500 for 205 (25%) donors. CONCLUSIONS: Our results can be used to inform strategies to minimize the financial burden of living donation, which may help improve the donation experience and increase the number of living donor kidney transplants.

Association of Baclofen With Encephalopathy in Patients With Chronic Kidney Disease.

IMPORTANCE: At least 30 case reports have linked the muscle relaxant baclofen to encephalopathy in patients with chronic kidney disease (CKD). OBJECTIVE: To compare the 30-day risk of encephalopathy in patients with CKD and newly prescribed baclofen at greater than or equal to 20 mg per day vs less than 20 mg per day. The secondary objective was to compare the risk of encephalopathy in baclofen users vs nonusers. DESIGN, SETTING, AND PARTICIPANTS: Retrospective population-based cohort study in Ontario, Canada (2007-2018) using linked health care data. Participants comprised 15 942 older adults (aged 66 years or older) with CKD (defined as an estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m2 but not receiving dialysis). The primary cohort was restricted to patients who were newly prescribed baclofen; participants in the secondary cohort were new users and nonusers. EXPOSURES: Prescription for oral baclofen greater than or equal to 20 mg per day vs less than 20 mg per day. MAIN OUTCOMES AND MEASURES: Hospital admission with encephalopathy, defined as a main diagnosis of delirium, disorientation, transient alteration of awareness, transient cerebral ischemic attack, or unspecified dementia within 30 days of starting baclofen. Inverse probability of treatment weighting on the propensity score was used to balance comparison groups on indicators of baseline health. Weighted risk ratios (RRs) were obtained using modified Poisson regression and weighted risk differences (RDs) using binomial regression. Prespecified subgroup analyses were conducted by eGFR category. RESULTS: The primary cohort comprised 15 942 patients with CKD (9699 [61%] women; median age, 77 years [interquartile range, 71-82]; 9707 [61%] patients started baclofen at ≥20 mg/d and 6235 [39%] at <20 mg/d). The primary outcome, hospitalization with encephalopathy, occurred in 108/9707 (1.11%) patients who started baclofen at greater than or equal to 20 mg per day and in 26/6235 (0.42%) who started baclofen at less than 20 mg per day; weighted RR, 3.54 (95% CI, 2.24 to 5.59); weighted RD, 0.80% (95% CI, 0.55% to 1.04%). In subgroup analysis, the absolute risk increased progressively at lower eGFR (weighted RD eGFR 45-59, 0.42% [95% CI, 0.19%-0.64%]; eGFR 30-44, 1.23% [95% CI, 0.62%-1.84%]; eGFR <30, 2.90% [95% CI, 1.30%-4.49%]; P for interaction, <.001]). In the secondary comparison with 284 263 nonusers, both groups of baclofen users had a higher risk of encephalopathy (<20 mg/d weighted RR, 5.90 [95% CI, 3.59 to 9.70] and ≥20 mg/d weighted RR, 19.8 [95% CI, 14.0 to 28.0]). CONCLUSIONS AND RELEVANCE: Among older patients with CKD who were newly prescribed baclofen, the 30-day incidence of encephalopathy was increased among those prescribed higher doses compared with lower doses. If verified, these risks should be balanced against the benefits of baclofen use.

Gestational hypertension and preeclampsia in living kidney donors.

BACKGROUND: Young women wishing to become living kidney donors frequently ask whether nephrectomy will affect their future pregnancies. METHODS: We conducted a retrospective cohort study of living kidney donors involving 85 women (131 pregnancies after cohort entry) who were matched in a 1:6 ratio with 510 healthy nondonors from the general population (788 pregnancies after cohort entry). Kidney donations occurred between 1992 and 2009 in Ontario, Canada, with follow-up through linked health care databases until March 2013. Donors and nondonors were matched with respect to age, year of cohort entry, residency (urban or rural), income, number of pregnancies before cohort entry, and the time to the first pregnancy after cohort entry. The primary outcome was a hospital diagnosis of gestational hypertension or preeclampsia. Secondary outcomes were each component of the primary outcome examined separately and other maternal and fetal outcomes. RESULTS: Gestational hypertension or preeclampsia was more common among living kidney donors than among nondonors (occurring in 15 of 131 pregnancies [11%] vs. 38 of 788 pregnancies [5%]; odds ratio for donors, 2.4; 95% confidence interval, 1.2 to 5.0; P=0.01). Each component of the primary outcome was also more common among donors (odds ratio, 2.5 for gestational hypertension and 2.4 for preeclampsia). There were no significant differences between donors and nondonors with respect to rates of preterm birth (8% and 7%, respectively) or low birth weight (6% and 4%, respectively). There were no reports of maternal death, stillbirth, or neonatal death among the donors. Most women had uncomplicated pregnancies after donation. CONCLUSIONS: Gestational hypertension or preeclampsia was more likely to be diagnosed in kidney donors than in matched nondonors with similar indicators of baseline health. (Funded by the Canadian Institutes of Health Research and others.).

Direct and indirect costs incurred by Australian living kidney donors.

AIM: To describe the direct and indirect costs incurred by Australian living kidney donors. METHODS: A total of 55 living kidney donors from three centres in Perth, Australia and one centre in Melbourne, Australia (2010-2014) was studied. Forty-nine donors provided information on expenses incurred during the donor evaluation period and up to 3 months after donation. A micro-costing approach was used to measure and value the units of resources consumed. Expenses were grouped as direct costs (ground and air travel, accommodation, and prescription medications) and indirect costs (lost wages and lost productivity). Costs were standardized to the year 2016 in Australian dollars. RESULTS: The most common direct costs were for ground travel (100%), parking (76%), and post-donation pain medications or antibiotics (73%). The highest direct costs were for air travel (median $1986 [three donors]) and ground travel (median $459 [49 donors]). Donors also reported lost wages (median $9891 [37 donors]). The inability to perform household activities or care for dependants were reported by 32 (65%) and 23 (47%) donors. Total direct costs averaged $1682 per donor (median $806 among 49 donors). Total indirect costs averaged $7249 per donor (median $7273 among 49 donors). Total direct and indirect costs averaged $8932 per donor (median $7963 among 49 donors). CONCLUSION: Many Australian living kidney donors incur substantial costs during the donation process. Our findings inform the continued development of policies and programmes designed to minimize costs incurred by living kidney donors.

Antibiotic Prescribing for Nonbacterial Acute Upper Respiratory Infections in Elderly Persons.

BACKGROUND: Reducing inappropriate antibiotic prescribing for acute upper respiratory tract infections (AURIs) requires a better understanding of the factors associated with this practice. OBJECTIVE: To determine the prevalence of antibiotic prescribing for nonbacterial AURIs and whether prescribing rates varied by physician characteristics. DESIGN: Retrospective analysis of linked administrative health care data. SETTING: Primary care physician practices in Ontario, Canada (January-December 2012). PATIENTS: Patients aged 66 years or older with nonbacterial AURIs. Patients with cancer or immunosuppressive conditions and residents of long-term care homes were excluded. MEASUREMENTS: Antibiotic prescriptions for physician-diagnosed AURIs. A multivariable logistic regression model with generalized estimating equations was used to examine whether prescribing rates varied by physician characteristics, accounting for clustering of patients among physicians and adjusting for patient-level covariates. RESULTS: The cohort included 8990 primary care physicians and 185 014 patients who presented with a nonbacterial AURI, including the common cold (53.4%), acute bronchitis (31.3%), acute sinusitis (13.6%), or acute laryngitis (1.6%). Forty-six percent of patients received an antibiotic prescription; most prescriptions were for broad-spectrum agents (69.9% [95% CI, 69.6% to 70.2%]). Patients were more likely to receive prescriptions from mid- and late-career physicians than early-career physicians (rate difference, 5.1 percentage points [CI, 3.9 to 6.4 percentage points] and 4.6 percentage points [CI, 3.3 to 5.8 percentage points], respectively), from physicians trained outside of Canada or the United States (3.6 percentage points [CI, 2.5 to 4.6 percentage points]), and from physicians who saw 25 to 44 patients per day or 45 or more patients per day than those who saw fewer than 25 patients per day (3.1 percentage points [CI, 2.1 to 4.0 percentage points] and 4.1 percentage points [CI, 2.7 to 5.5 percentage points], respectively). LIMITATION: Physician rationale for prescribing was unknown. CONCLUSION: In this low-risk elderly cohort, 46% of patients with a nonbacterial AURI were prescribed antibiotics. Patients were more likely to receive prescriptions from mid- or late-career physicians with high patient volumes and from physicians who were trained outside of Canada or the United States. PRIMARY FUNDING SOURCE: Ontario Ministry of Health and Long-term Care, Academic Medical Organization of Southwestern Ontario, Schulich School of Medicine and Dentistry, Western University, and Lawson Health Research Institute.

Effect of Coaching to Increase Water Intake on Kidney Function Decline in Adults With Chronic Kidney Disease: The CKD WIT Randomized Clinical Trial.

Importance: In observational studies, increased water intake is associated with better kidney function. Objective: To determine the effect of coaching to increase water intake on kidney function in adults with chronic kidney disease. Design, Setting, and Participants: The CKD WIT (Chronic Kidney Disease Water Intake Trial) randomized clinical trial was conducted in 9 centers in Ontario, Canada, from 2013 until 2017 (last day of follow-up, May 25, 2017). Patients had stage 3 chronic kidney disease (estimated glomerular filtration rate [eGFR] 30-60 mL/min/1.73 m2 and microalbuminuria or macroalbuminuria) and a 24-hour urine volume of less than 3.0 L. Interventions: Patients in the hydration group (n = 316) were coached to drink more water, and those in the control group (n = 315) were coached to maintain usual intake. Main Outcomes and Measures: The primary outcome was change in kidney function (eGFR from baseline to 12 months). Secondary outcomes included 1-year change in plasma copeptin concentration, creatinine clearance, 24-hour urine albumin, and patient-reported overall quality of health (0 [worst possible] to 10 [best possible]). Results: Of 631 randomized patients (mean age, 65.0 years; men, 63.4%; mean eGFR, 43 mL/min/1.73 m2; median urine albumin, 123 mg/d), 12 died (hydration group [n = 5]; control group [n = 7]). Among 590 survivors with 1-year follow-up measurements (95% of 619), the mean change in 24-hour urine volume was 0.6 L per day higher in the hydration group (95% CI, 0.5 to 0.7; P < .001). The mean change in eGFR was -2.2 mL/min/1.73 m2 in the hydration group and -1.9 mL/min/1.73 m2 in the control group (adjusted between-group difference, -0.3 mL/min/1.73 m2 [95% CI, -1.8 to 1.2; P = .74]). The mean between-group differences (hydration vs control) in secondary outcomes were as follows: plasma copeptin, -2.2 pmol/L (95% CI, -3.9 to -0.5; P = .01); creatinine clearance, 3.6 mL/min/1.73 m2 (95% CI, 0.8 to 6.4; P = .01); urine albumin, 7 mg per day (95% CI, -4 to 51; P = .11); and quality of health, 0.2 points (95% CI, -0.3 to 0.3; P = .22). Conclusions and Relevance: Among adults with chronic kidney disease, coaching to increase water intake compared with coaching to maintain the same water intake did not significantly slow the decline in kidney function after 1 year. However, the study may have been underpowered to detect a clinically important difference. Trial Registration: clinicaltrials.gov Identifier: NCT01766687.

Plasmapheresis for the treatment of kidney diseases.

The purpose of this review is to examine the evidence supporting the application of plasma exchange in renal disease. Our review focuses on the following 6 most common renal indications for plasma exchange based on 2014 registry data from the Canadian Apheresis Group: (i) thrombotic thrombocytopenic purpura (TTP)/hemolytic uremic syndrome; (ii) renal transplantation, (iii) anti-neutrophil cytoplasm antibodies-associated vasculitis, (iv) cryoglobulinemia, (v) focal segmental glomerulosclerosis, and (vi) Goodpasture syndrome. The rarity of these diseases and their rapid, often fatal course mean that randomized controlled studies of plasma exchange are rarely conducted. Although evidence from an adequately powered randomized controlled trial supports the use of plasma exchange to treat thrombotic thrombocytopenic purpura, the use of plasma exchange to treat other renal diseases is only supported by observational and mechanistic studies. Larger well-designed trials are needed to clarify the potential role of plasma exchange in renal disease. Growing international collaboration will improve the quality of future studies in this area.