Muscle Mass and Serum Creatinine Concentration by Race and Ethnicity among Hemodialysis Patients.

SIGNIFICANCE STATEMENT: Serum creatinine is a product of skeletal muscle metabolism. Differences in serum creatinine concentration between Black and non-Black individuals have been attributed to differences in muscle mass but have not been thoroughly examined. Furthermore, other race and ethnic groups have not been considered. If differences in body composition explain differences in serum concentration by race or ethnicity, then estimates of body composition could be used in eGFR equations rather than race. Adjustment for intracellular water (ICW) as a proxy of muscle mass among patients with kidney failure in whom creatinine clearance should minimally influence serum concentration does not explain race- and ethnicity-dependent differences. BACKGROUND: Differences in serum creatinine concentration among groups defined by race and ethnicity have been ascribed to differences in muscle mass. We examined differences in serum creatinine by race and ethnicity in a cohort of patients receiving hemodialysis in whom creatinine elimination by the kidney should have little or no effect on serum creatinine concentration and considered whether these differences persisted after adjustment for proxies of muscle mass. METHODS: We analyzed data from 501 participants in the A Cohort Study to Investigate the Value of Exercise in ESKD/Analyses Designed to Investigate the Paradox of Obesity and Survival in ESKD study who had been receiving hemodialysis for >1 year. We examined the independent associations among race and ethnicity (Black, Asian, non-Hispanic White, and Hispanic), serum creatinine, and ICW (L/m 2 ), a proxy for muscle mass, derived by whole-body multifrequency bioimpedance spectroscopy, using multivariable linear regression with adjustment for several demographic, clinical, and laboratory characteristics. We examined the association of race and ethnicity with serum creatinine concentration with and without adjustment for ICW. RESULTS: Black, Asian, and Hispanic patients had higher serum creatinine concentrations (+1.68 mg/dl [95% confidence interval (CI), 1.09 to 2.27], +1.61 mg/dl [95% CI, 0.90 to 2.32], and +0.83 [95% CI, 0.08 to 1.57], respectively) than non-Hispanic White patients. Overall, ICW was associated with serum creatinine concentration (0.26 mg/dl per L/m 2 ICW; 95% CI, 0.006 to 0.51) but was not statistically significantly different by race and ethnicity. Black, Asian, and Hispanic race and ethnicity remained significantly associated with serum creatinine concentration after adjustment for ICW. CONCLUSION: Among patients receiving dialysis, serum creatinine was higher in Black, Asian, and Hispanic patients than in non-Hispanic White patients. Differences in ICW did not explain the differences in serum creatinine concentration across race groups.

Rurality of patient residence and access to transplantation among children with kidney failure in the United States.

BACKGROUND: Residence in rural areas is often a barrier to health care access. To date, differences in access to kidney transplantation among children who reside in rural and micropolitan areas of the US have not been explored. METHODS: A retrospective cohort study of children < 18 years who developed kidney failure between 2000 and 2019 according to the United States Renal Data System (USRDS). We examined the association between rurality of patient residence and time to living and/or deceased donor kidney transplantation (primary outcomes) and waitlist registration (secondary outcome) using Fine-Gray models. RESULTS: We included 18,530 children, of whom 14,175 (76.5%) received a kidney transplant (39.8% from a living and 60.2% from a deceased donor). Residence in micropolitan (subhazard ratio (SHR) 1.16; 95% CI 1.06-1.27) and rural (SHR 1.18; 95% CI 1.06-1.3) areas was associated with better access to living donor transplantation compared with residence in metropolitan areas. There was no statistically significant association between residence in micropolitan (SHR, 0.95; 95%CI 0.88-1.03) and rural (SHR, 0.94; 95%CI 0.86-1.03) areas compared with metropolitan areas in the access of children to deceased donor transplantation. There was also no difference in the time to waitlist registration comparing micropolitan (SHR 1.04; 95%CI 0.98-1.10) and rural (SHR 1.05; 95% CI 0.98-1.13) versus metropolitan areas. CONCLUSIONS: In children with kidney failure, residence in rural and micropolitan areas was associated with better access to living donor transplantation and similar access to deceased donor transplantation compared with residence in metropolitan areas.

Association Between Dialysis Facility Ownership and Mortality Risk in Children With Kidney Failure.

Importance: In adults, treatment at profit dialysis facilities has been associated with a higher risk of death. Objective: To determine whether profit status of dialysis facilities is associated with the risk of death in children with kidney failure treated with dialysis and whether any such association is mediated by differences in access to transplant. Design, Setting, and Participants: This retrospective cohort study reviewed US Renal Data System records of 15 359 children who began receiving dialysis for kidney failure between January 1, 2000, and December 31, 2019, in US dialysis facilities. The data analysis was performed between May 2, 2022, and June 15, 2023. Exposure: Time-updated profit status of dialysis facilities. Main Outcomes and Measures: Adjusted Fine-Gray models were used to determine the association of time-updated profit status of dialysis facilities with risk of death, treating kidney transplant as a competing risk. Cox proportional hazards regression models were also used to determine time-updated profit status with risk of death regardless of transplant status. Results: The final cohort included 8465 boys (55.3%) and 6832 girls (44.7%) (median [IQR] age, 12 [3-15] years). During a median follow-up of 1.4 (IQR, 0.6-2.7) years, with censoring at transplant, the incidence of death was higher at profit vs nonprofit facilities (7.03 vs 4.06 per 100 person-years, respectively). Children treated at profit facilities had a 2.07-fold (95% CI, 1.83-2.35) higher risk of death compared with children at nonprofit facilities in adjusted analyses accounting for the competing risk of transplant. When follow-up was extended regardless of transplant status, the risk of death remained higher for children treated in profit facilities (hazard ratio, 1.47; 95% CI, 1.35-1.61). Lower access to transplant in profit facilities mediated 67% of the association between facility profit status and risk of death (95% CI, 45%-100%). Conclusions and Relevance: Given the higher risk of death associated with profit dialysis facilities that is partially mediated by lower access to transplant, the study's findings indicate a need to identify root causes and targeted interventions that can improve mortality outcomes for children treated in these facilities.

Melatonin for migraine prevention in children and adolescents: A randomized, double-blind, placebo-controlled trial after single-blind placebo lead-in.

BACKGROUND: Melatonin is effective for migraine prevention in adults. We hypothesized that melatonin would also be effective for migraine prevention in children and adolescents. METHODS: This was a randomized, double-blind trial of melatonin (3 mg or 6 mg) versus placebo for migraine prevention in 10-17 year-olds with 4-28/28 headache days at baseline. Participants were recruited from the UCSF Child & Adolescent Headache Program, UCSF child neurology clinic, and social media advertisements. Migraine diagnosis was confirmed by a headache specialist. Participants completed an 8-week single-blind placebo run-in. Those meeting randomization criteria (≥4 headache days and ≥23/28 electronic diary entries during weeks 5-8) were randomized 1:1:1 to placebo:melatonin 3 mg:melatonin 6 mg nightly for 8 weeks. The primary outcome measure was migraine days in weeks 5-8 of randomized treatment between melatonin (combined 6 mg + 3 mg) versus placebo. We aimed to enroll n = 210. RESULTS: The study closed early due to slow enrollment (n = 72). Two participants were in the single-blind phase when the study closed, therefore the meaningful n = 70. Sixteen percent (11/70) were lost to follow-up during the single-blind phase. An additional 21% (15/70) did not meet randomization criteria (<4 headache days: n = 5, <23/28 diary days: n = 7, both: n = 3). Sixty-three percent (44/70) were eligible to randomize, of whom 42 randomized (n = 14 per arm). Taking another preventive at enrollment (OR 8.3, 95% CI 1.01 to 68.9) was the only variable associated with meeting randomization criteria. Of those randomized, 91% (38/42) provided diary data in the final 4-weeks. However, given the amount of missing data, only those with ≥21/28 diary days were analyzed-7/14 (50%) in the placebo group, and 20/28 (71%) in the melatonin groups combined. Median (IQR) migraine/migrainous days in weeks 5-8 of double-blind treatment was 2 (1-7) in the placebo group versus 2 (1-12) in the melatonin groups combined; the difference in medians (95% CI for the difference) was 0 days (-9 to 3). There were no differences in adverse events between groups. CONCLUSIONS: When compared to recall at enrollment, headache days decreased across the single-blind placebo phase and the double-blind phase. There was no suggestion of superiority of melatonin; however, given the substantial portion of missing data, numerically higher in the placebo arm, and underpowering, this should not be interpreted as proof of inefficacy. Melatonin was generally well tolerated with no serious adverse events. Future migraine preventive trials in this age group may find this trial helpful for anticipating enrollment needs if using a single-blind placebo run-in. Enriching for those already on a migraine preventive may improve randomization rates in future trials, though would change the generalizability of results.

Intensive BP Control in Patients with CKD and Risk for Adverse Outcomes.

SIGNIFICANCE STATEMENT: Although most guidelines recommend tightly controlling BP in patients with CKD, individuals with advanced kidney disease or severe albuminuria were not well-represented in trials examining the effect of this intervention on kidney outcomes. To examine the effect of intensive BP control on the risk of kidney outcomes in patients with CKD, the authors pooled individual-level data from seven trials. They found that overall, intensive BP control was associated with a 13% lower, but not significant, risk of a kidney outcome. However, the intervention's effect on the kidney outcome differed depending on baseline eGFR. Data from this pooled analysis suggested a benefit of intensive BP control in delaying KRT onset in patients with stages 4-5 CKD, but not necessarily in those with stage 3 CKD. BACKGROUND: The effect of intensive BP lowering (to systolic BP of <120 mm Hg) on the risk of kidney failure requiring KRT remains unclear in patients with advanced CKD. Such patients were not well represented in trials evaluating intensive BP control. METHODS: To examine the effect of intensive BP lowering on KRT risk-or when not possible, trial-defined kidney outcomes-we pooled individual-level data from seven trials that included patients with eGFR<60 ml/min per 1.73 m 2 . We performed prespecified subgroup analyses to evaluate the effect of intensive BP control by baseline albuminuria and eGFR (CKD stages 4-5 versus stage 3). RESULTS: Of 5823 trial participants, 526 developed the kidney outcome and 382 died. Overall, intensive (versus usual) BP control was associated with a lower risk of kidney outcome and death in unadjusted analyses but these findings did not achieve statistical significance. However, the intervention's effect on the kidney outcome differed depending on baseline eGFR ( P interaction=0.05). By intention-to-treat analysis, intensive (versus usual) BP control was associated with a 20% lower risk of the primary kidney outcome in those with CKD GFR stages 4-5, but not in CKD GFR stage 3. There was no interaction between intensive BP control and the severity of albuminuria for kidney outcomes. CONCLUSIONS: Data from this pooled analysis of seven trials suggest a benefit of intensive BP control in delaying KRT onset in patients with stages 4-5 CKD but not necessarily with stage 3 CKD. These findings suggest no evidence of harm from intensive BP control, but also point to the need for future trials of BP targets focused on populations with advanced kidney disease. PODCAST: This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/JASN/2023_02_27_JASN0000000000000060.mp3.

Association of Wildfire Air Pollution With Clinic Visits for Psoriasis.

This cross-sectional study examines whether clinic visits and online search interest for psoriasis were associated with wildfire air pollution after a delayed lag period.

Association of Exposure to Wildfire Air Pollution With Exacerbations of Atopic Dermatitis and Itch Among Older Adults.

This cross-sectional study evaluates the association of exposure to wildfire air pollution with exacerbations of atopic dermatitis and itch among adults aged 65 years or older.

Association Between Dialysis Facility Ownership and Access to the Waiting List and Transplant in Pediatric Patients With End-stage Kidney Disease in the US.

Importance: Care of adults at profit vs nonprofit dialysis facilities has been associated with lower access to transplant. Whether profit status is associated with transplant access for pediatric patients with end-stage kidney disease is unknown. Objective: To determine whether profit status of dialysis facilities is associated with placement on the kidney transplant waiting list or receipt of kidney transplant among pediatric patients receiving maintenance dialysis. Design, Setting, and Participants: This retrospective cohort study reviewed the US Renal Data System records of 13 333 patients younger than 18 years who started dialysis from 2000 through 2018 in US dialysis facilities (followed up through June 30, 2019). Exposures: Time-updated profit status of dialysis facilities. Main Outcomes and Measures: Cox models, adjusted for clinical and demographic factors, were used to examine time to wait-listing and receipt of kidney transplant by profit status of dialysis facilities. Results: A total of 13 333 pediatric patients who started receiving maintenance dialysis were included in the analysis (median age, 12 years [IQR, 3-15 years]; 6054 females [45%]; 3321 non-Hispanic Black patients [25%]; 3695 Hispanic patients [28%]). During a median follow-up of 0.87 years (IQR, 0.39-1.85 years), the incidence of wait-listing was lower at profit facilities than at nonprofit facilities, 36.2 vs 49.8 per 100 person-years, respectively (absolute risk difference, -13.6 (95% CI, -15.4 to -11.8 per 100 person-years; adjusted hazard ratio [HR] for wait-listing at profit vs nonprofit facilities, 0.79; 95% CI, 0.75-0.83). During a median follow-up of 1.52 years (IQR, 0.75-2.87 years), the incidence of kidney transplant (living or deceased donor) was also lower at profit facilities than at nonprofit facilities, 21.5 vs 31.3 per 100 person-years, respectively; absolute risk difference, -9.8 (95% CI, -10.9 to -8.6 per 100 person-years) adjusted HR for kidney transplant at profit vs nonprofit facilities, 0.71 (95% CI, 0.67-0.74). Conclusions and Relevance: Among a cohort of pediatric patients receiving dialysis in the US from 2000 through 2018, profit facility status was associated with longer time to wait-listing and longer time to kidney transplant.

Incidence and Risk Factors for Dialysis Reinitiation among Patients with a History of Dialysis Dependency.

BACKGROUND AND OBJECTIVES: Recovery of kidney function after the start of maintenance dialysis can occur, but data on the incidence and risk factors for restarting dialysis after recovery of kidney function in this population are limited. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We conducted a retrospective study of adult Medicare beneficiaries who started dialysis between 2005 and 2015 according to the United States Renal Data System but who had recovery of kidney function (defined as a ≥90-day dialysis-free interval). We identified risk factors that were associated with the risk for the reinitiation of dialysis within a 3-year time frame following the recovery of kidney function and at any time during follow-up using Cox proportional hazards models. RESULTS: Of the 34,530 individuals previously on dialysis who had recovery of kidney function, 7217 (21%) restarted dialysis (absolute rate of 11.5 per 100 person-years) within 3 years of recovery of kidney function, and 9120 (26%) restarted dialysis during the entire follow-up period (absolute rate of 8.8 per 100 person-years). Among those with CKD stage 1 or 2 after recovery of kidney function, 10% of individuals restarted dialysis within 3 years of their recovery of kidney function, whereas among those with CKD stage 3, 4, or 5, 13%, 27%, and 36% of individuals restarted dialysis within 3 years of recovery of kidney function, respectively. Age at first dialysis, cause of kidney disease, history of CKD or nephrology care prior to starting dialysis, presence of heart failure, CKD stage following recovery of kidney function, and location of first dialysis initiation (inpatient versus outpatient) were some of the risk factors that were strongly associated with the risk of restarting dialysis after the recovery of kidney function. CONCLUSIONS: Over one in five patients with recovery of kidney function after kidney failure restarted dialysis within 3 years.

Disparities in access for melanoma screening by region, specialty, and insurance: A cross-sectional audit study.

Background: Early detection of melanoma is critical for positive outcomes. However, access for the diagnosis of melanoma remains problematic for segments of the general population. Objective: To compare the rates of dermatology and family medicine practitioner acceptances for a public insurance (Medicaid) versus private insurance (Anthem Blue Cross) and clinic wait times for an appointment for a changing pigmented skin lesion concerning melanoma in rural and urban regions in California. Methods: Cross-sectional audit study between June 2017 and March 2019; scripted phone calls were made to dermatology and family medicine practices (FMPs). Results: Family medicine and dermatology practices in both regions had significantly decreased acceptance of Medicaid. Dermatology practices had 11.3% to 13.0% Medicaid acceptance rates that were less than FMP rates of 28% to 36%. In both regions, FMP wait times were 2.4- to 3.2-fold longer for public versus private insurance; there were little differences in wait times for the 2 insurance types in dermatology practices, in both regions. Limitations: Assessment of only 2 regions in the state of California. Conclusion: Delays at FMPs and insurance types limit access to melanoma screening in California for underserved segments of the general population, which has implications for melanoma outcomes and health policy.

Increased Colorectal Cancer Screening Sustained with Mailed Fecal Immunochemical Test Outreach.

BACKGROUND & AIMS: Reports of mailed fecal immunochemical test (FIT) outreach effectiveness over time are minimal. We aimed to better evaluate a mailed FIT program with longitudinal metrics. METHODS: A total of 10,771 patients aged 50 to 75 years not up-to-date with colorectal cancer screening were randomized to intervention or usual care. The intervention arm received an advanced notification call and informational postcard prior to a mailed FIT. Usual care was at the discretion of the primary care provider. Patients were followed for up to 2.5 years. The primary outcome was the difference in cumulative proportion of completed FIT screening between arms. Screening was further examined with the proportion of time up-to-date, consistency of adherence, and frequency of abnormal FIT. RESULTS: The cumulative proportion of FIT completion was higher in the outreach intervention (73.2% vs 55.1%; P < .001). The proportion of time covered by screening was higher in the intervention group (46.8% vs 27.3%; Δ19.6%; 95% confidence interval, 18.2%-20.9%). Patients assigned to FIT outreach were more likely to consistently complete FITs (2 completed of 2 offered) (50.1% vs 21.8%; P < .001). However, for patients who did not complete the FIT during the first cycle, only 17.1% completed a FIT during the second outreach cycle. The number and overall proportion of abnormal FIT was significantly higher in the outreach intervention (6.9% Outreach vs 4.1% Usual Care; P < .01). CONCLUSIONS: Organized mailed FIT outreach significantly increased colorectal cancer screening over multiple years in this safety-net health system. Although mailing was overall effective, the effect was modest in patients who did not complete FIT in first cycle of intervention. (ClincialTrials.gov, NCT02613260).

Disentangling the impact of alcohol use and hepatitis C on insulin action in Latino individuals.

BACKGROUND: Alcohol, insulin resistance (IR), and hepatitis C (HCV) are all significant contributors to adverse outcomes of chronic liver disease. Latinos are disproportionately affected by these risk factors. We investigated the relationship between alcohol use and insulin action in a prospective cohort of Latino individuals with and without HCV. METHODS: One hundred fifty-three nondiabetic Latino individuals (60 HCV+, 93 HCV-) underwent clinical evaluation and metabolic testing; 56 had repeat testing over a median follow-up of 1.5 years. Peripheral IR and hepatic IR were measured via steady-state plasma glucose (SSPG) and endogenous glucose production during a two-step, 240-min insulin suppression test. Insulin secretion (IS) was measured using the graded glucose infusion test. Alcohol use was categorized as none, moderate (≤1 drink/day for women and ≤2 drinks/day for men), and heavy (>moderate). Multivariable models including HCV status assessed associations of alcohol use with baseline SSPG, hepatic IR and IS, and changes in these parameters over time. RESULTS: Overall, the median age was 44 years, 63.4% were male, 66.7% overweight/ obese, and 31.9% had heavy lifetime alcohol use while 60.4% had moderate lifetime alcohol use. SSPG and IS were similar by levels of alcohol use at baseline and alcohol use was not statistically significantly associated with change in these measures over time. However, lifetime daily heavy alcohol use (vs. not heavy, coef 2.4 µU-mg/kg-min-ml, p = 0.04) and HCV status (coef 4.4 µU-mg/kg-min-ml, p = 0.0003) were independently associated with higher baseline hepatic IR, and current heavy alcohol use was associated with greater change in hepatic IR in follow-up (coef 5.8 µU-mg/kg-min-ml, p = 0.03). CONCLUSIONS: In this cohort of Latino individuals, lifetime and current heavy alcohol use influenced hepatic IR and its change over time. Strategies to decrease rates of heavy alcohol use or increase abstinence along with lifestyle modification and anti-HCV therapy to reduce metabolic risk are critical to prevent adverse liver and metabolic outcomes in Latino individuals.

Longitudinal Assessment of Body Composition and Its Association With Survival Among Participants of the ACTIVE/ADIPOSE Study.

OBJECTIVES: The importance of muscle wasting as a predictor of mortality in the hemodialysis population is not clear. Lack of association of muscle mass with survival in some studies could be related to reliance on single measures or to incorporation of excess extracellular water (ECW) into estimates of muscle mass. We examined changes in body composition over a 2-year period and the association of body composition with survival. DESIGN AND METHODS: We analyzed data from 325 adults receiving hemodialysis in the Bay Area. We estimated ECW, intracellular water (ICW), and fat mass by whole-body bioimpedance spectroscopy (BIS) at 0, 12, and 24 months from enrollment. We used linear mixed modeling to examine changes in body mass index and BIS-derived estimates of body composition and Cox modeling with BIS-derived estimates as time-varying independent variables to examine associations between body composition and survival in multivariable analyses. RESULTS: Body mass index declined over time. Considering individual components of body composition, ICW declined (-0.09 kg/m2 per year, 95% confidence interval -0.14 to -0.04), but fat mass and ECW did not change significantly. There were 120 deaths over a median of 5.2 years. The relationship between ICW and mortality was not linear such that the association was steeper at low values of ICW, whereas higher ICW was associated with better survival that was relatively stable above 9 kg/m2. Higher ECW was associated with higher mortality, and fat mass was not associated with survival. These associations were independent of markers of inflammation and nutritional status. CONCLUSIONS: ICW declined over 2 years in this cohort, whereas fat mass and ECW remained relatively stable. Higher ICW was associated with better survival, but higher fat mass was not. Higher ECW was associated with worse survival. These results suggest that muscle mass may predict survival among patients on hemodialysis.

Bariatric surgery prior to transplantation and risk of early hospital re-admission, graft failure, or death following kidney transplantation.

Bariatric surgery has been shown to be safe in the dialysis population. Whether bariatric surgery before kidney transplantation influences posttransplant outcomes has not been examined nationally. We included severely obese (BMI >35) dialysis patients between 18 and 70 years who received a kidney transplant according to the US Renal Data System. We determined the association between history of bariatric surgery and risk of 30-day readmission, graft failure, or death after transplantation using multivariable logistic, Fine-Gray, and Cox models. We included 12 573 patients, of whom 503 (4%) received bariatric surgery before transplantation. Median age at transplant was 53 years; 42% were women. Overall, history of bariatric surgery was not statistically significantly associated with graft failure (HR 1.02; 95% CI 0.77-1.35) or death (HR 1.10; 95% CI 0.84-1.45). However, sleeve gastrectomy (vs. no bariatric surgery) was associated with lower risk of graft failure (HR 0.39; 95% CI 0.16-0.95). In conclusion, history of bariatric surgery prior to kidney transplantation was not associated with allograft or patient survival, but findings varied by surgery type. Sleeve gastrectomy was associated with better graft survival and should be considered in severely obese transplant candidates receiving dialysis.

Association of Wildfire Air Pollution and Health Care Use for Atopic Dermatitis and Itch.

IMPORTANCE: Air pollution is a worldwide public health issue that has been exacerbated by recent wildfires, but the relationship between wildfire-associated air pollution and inflammatory skin diseases is unknown. OBJECTIVE: To assess the associations between wildfire-associated air pollution and clinic visits for atopic dermatitis (AD) or itch and prescribed medications for AD management. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional time-series study assessed the associations of air pollution resulting from the California Camp Fire in November 2018 and 8049 dermatology clinic visits (4147 patients) at an academic tertiary care hospital system in San Francisco, 175 miles from the wildfire source. Participants included pediatric and adult patients with AD or itch from before, during, and after the time of the fire (October 2018 through February 2019), compared with those with visits in the same time frame of 2015 and 2016, when no large wildfires were near San Francisco. Data analysis was conducted from November 1, 2019, to May 30, 2020. EXPOSURES: Wildfire-associated air pollution was characterized using 3 metrics: fire status, concentration of particulate matter less than 2.5 µm in diameter (PM2.5), and satellite-based smoke plume density scores. MAIN OUTCOMES AND MEASURES: Weekly clinic visit counts for AD or itch were the primary outcomes. Secondary outcomes were weekly numbers of topical and systemic medications prescribed for AD in adults. RESULTS: Visits corresponding to a total of 4147 patients (mean [SD] age, 44.6 [21.1] years; 2322 [56%] female) were analyzed. The rates of visits for AD during the Camp Fire for pediatric patients were 1.49 (95% CI, 1.07-2.07) and for adult patients were 1.15 (95% CI, 1.02-1.30) times the rate for nonfire weeks at lag 0, adjusted for temperature, relative humidity, patient age, and total patient volume at the clinics for pediatric patients. The adjusted rate ratios for itch clinic visits during the wildfire weeks were 1.82 (95% CI, 1.20-2.78) for the pediatric patients and 1.29 (95% CI, 0.96-1.75) for adult patients. A 10-µg/m3 increase in weekly mean PM2.5 concentration was associated with a 7.7% (95% CI, 1.9%-13.7%) increase in weekly pediatric itch clinic visits. The adjusted rate ratio for prescribed systemic medications in adults during the Camp Fire at lag 0 was 1.45 (95% CI, 1.03-2.05). CONCLUSIONS AND RELEVANCE: This cross-sectional study found that short-term exposure to air pollution due to the wildfire was associated with increased health care use for patients with AD and itch. These results may provide a better understanding of the association between poor air quality and skin health and guide health care professionals' counseling of patients with skin disease and public health practice.

Association between Longer Travel Distance for Transplant Care and Access to Kidney Transplantation and Graft Survival in the United States.

BACKGROUND: Transplant candidates may gain an advantage by traveling to receive care at a transplant center that may have more favorable characteristics than their local center. Factors associated with longer travel distance for transplant care and whether the excess travel distance (ETD) is associated with access to transplantation or with graft failure are unknown. METHODS: This study of adults in the United States wait-listed for kidney transplantation in 1995-2015 used ETD, defined as distance a patient traveled beyond the nearest transplant center for initial waiting list registration. We used linear regression to examine patient and center characteristics associated with ETD and Fine-Gray models to examine the association between ETD (modeled as a spline) and time to deceased or living donor transplantation or graft failure. RESULTS: Of 373,365 patients, 11% had an ETD≥50 miles. Traveling excess distance was more likely among patients who were of non-Black race or those whose nearest transplant center had lower annual living donor transplant volume. At an ETD of 50 miles, we observed a lower likelihood of deceased donor transplantation (subhazard ratio [SHR], 0.85; 95% confidence interval [95% CI], 0.84 to 0.87) but higher likelihood of living donor transplantation (SHR, 1.14; 95% CI, 1.12 to 1.16) compared with those who received care at their nearest center. ETD was weakly associated with higher risk of graft failure. CONCLUSIONS: Patients who travel excess distances for transplant care have better access to living donor but not deceased donor transplantation and slightly higher risk of graft failure. Traveling excess distances is not clearly associated with better outcomes, especially if living donors are unavailable.

Recovery of kidney function after dialysis initiation in children and adults in the US: A retrospective study of United States Renal Data System data.

BACKGROUND: Little is known about factors associated with recovery of kidney function-and return to dialysis independence-or temporal trends in recovery after starting outpatient dialysis in the United States. Understanding the characteristics of individuals who may have the potential to recover kidney function may promote better recognition of such events. The goal of this study was to determine factors associated with recovery of kidney function in children compared with adults starting dialysis in the US. METHODS AND FINDINGS: We determined factors associated with recovery of kidney function-defined as survival and discontinuation of dialysis for ≥90-day period-in children versus adults who started maintenance dialysis between 1996 and 2015 according to the United States Renal Data System (USRDS) followed through 2016 in a retrospective cohort study. We also examined temporal trends in recovery rates over the last 2 decades in this cohort. Among 1,968,253 individuals included for study, the mean age was 62.6 ± 15.8 years, and 44% were female. Overall, 4% of adults (83,302/1,953,881) and 4% of children (547/14,372) starting dialysis in the outpatient setting recovered kidney function within 1 year. Among those who recovered, the median time to recovery was 73 days (interquartile range [IQR] 43-131) in adults and 100 days (IQR 56-189) in children. Accounting for the competing risk of death, children were less likely to recover kidney function compared with adults (sub-hazard ratio [sub-HR] 0.81; 95% CI 0.74-0.89, p-value <0.001; point estimates <1 indicating increased risk for a negative outcome). Non-Hispanic black (NHB) adults were less likely to recover compared with non-Hispanic white (NHW) adults, but these racial differences were not observed in children. Of note, a steady increase in the incidence of recovery of kidney function was noted initially in adults and children between 1996 and 2010, but this trend declined thereafter. The diagnoses associated with the highest recovery rates of recovery were acute tubular necrosis (ATN) and acute interstitial nephritis (AIN) in both adults and children, where 25%-40% of patients recovered kidney function depending on the calendar year of dialysis initiation. Limitations to our study include the potential for residual confounding to be present given the observational nature of our data. CONCLUSIONS: In this study, we observed that discontinuation of outpatient dialysis due to recovery occurred in 4% of patients with end-stage kidney disease (ESKD) and was more common among those with ATN or AIN as the cause of their kidney disease. While recovery rates rose initially, they declined starting in 2010. Additional studies are needed to understand how to best recognize and promote recovery in patients whose potential to discontinue dialysis is high in the outpatient setting.

Benign paroxysmal torticollis: phenotype, natural history, and quality of life.

BACKGROUND: Benign paroxysmal torticollis (BPT) is characterized by attacks of head tilt associated with vomiting, irritability, and/or ataxia in early childhood. BPT is associated with migraine but risk factors are unknown. Impact on quality of life is also unknown. METHODS: Parents/caregivers of children with ongoing or resolved BPT participated in telephone interviews (n = 73). Those with ongoing BPT completed the Infant Toddler Quality of Life questionnaire (ITQoL). RESULTS: Median age of children at the time of interview was 2.9 years (range 0.25-23). BPT was ongoing in 52% (n = 38). Nineteen percent (n = 14) developed migraine (median age 9.25 years, range 2.5-23) and 63% (n = 46) developed another episodic syndrome associated with migraine. Proportion of patients who developed migraine was higher among those with certain migrainous symptoms during BPT attacks vs. those without: phonophobia (58 vs. 21%, p = 0.02), photophobia and phonophobia (55 vs. 23%, p = 0.05), and photophobia, phonophobia, and motion sensitivity (60 vs. 22%, p = 0.02). ITQoL results showed significant impact of BPT on quality of life. CONCLUSIONS: Children with BPT may develop migraine or other episodic syndromes associated with migraine. Presence of migrainous features during BPT episodes may increase likelihood of developing migraine. Though characterized as "benign," BPT can significantly impact children and families. IMPACT: Benign paroxysmal torticollis (BPT) is a rare condition of early childhood characterized by episodes of head tilt associated with vomiting, irritability, ataxia, pallor, and/or malaise. This cohort study describes the phenotypic spectrum of BPT, variable treatment, natural history and association with migraine, and impact on development and quality of life. Children with BPT may go on to develop migraine or episodic syndromes that may be associated with migraine; presence of migrainous features during attacks may increase odds of developing migraine. BPT can have significant impact on quality of life, demonstrated by findings from the Infant Toddler Quality of Life questionnaire.