Assessment of breast cancer chemotherapy dose reduction in an integrated healthcare delivery system.

PURPOSE: Most cytotoxic drugs are dosed using body surface area (BSA), yet not all cancer patients receive the full BSA-determined dose. Prior work suggests that breast cancer patients who are obese are more likely to experience dose reduction than normal weight patients. However, the factors driving dose reduction remain unclear. METHODS: In 452 women diagnosed with stage I-IIIA primary breast cancer at Kaiser Permanente Northern California, we evaluated the association between obesity and dose reduction, and further explored other factors in relation to dose reduction, including various sociodemographic characteristics, tumor characteristics, and comorbidities. Study participants were a part of the Pathways Study, diagnosed between 2006 and 2013 and treated with cyclophosphamide + doxorubicin, followed by paclitaxel (ACT). Dose reduction was assessed using first cycle dose proportion (FCDP) and average relative dose intensity (ARDI), a metric of dose intensity over the course of chemotherapy. RESULTS: Overall, 8% of participants received a FCDP < 90% and 21.2% had an ARDI < 90%, with dose reduction increasing with body mass index. In adjusted logistic regression models, obese women had 4.1-fold higher odds of receiving an ARDI < 90% than normal weight women (95% CI: 1.9-8.9; p-trend = 0.0006). Increasing age was positively associated with an ADRI < 90%, as was the presence of comorbidity. Dose reduction was less common in later calendar years. CONCLUSION: Results offer insight on factors associated with chemotherapy dosing for a common breast cancer regimen. Larger studies are required to evaluate relevance to other regimens, and further work will be needed to determine whether dose reductions impact outcomes in obese women.

Predictor of left main coronary artery size: an intravascular ultrasound study in Southeast Asia population.

Left main (LM) percutaneous coronary intervention (PCI) has expanded rapidly in the past decade, with up to fourfold increase annually. Recent trials found that intravascular imaging (IVI)-guided LM PCI resulted in lower risks of cardiac death and stent failure due to suboptimal PCI compared to angiography-guided PCI. IVI usage has increased in recent years; however, its utilization remains variable across regions and is still incredibly low in developing countries. Furthermore, to date, there is no data about LM size in the Southeast Asian population. This study aims to determine the mean external elastic membrane (EEM) diameter, cross-sectional area (CSA) of LM, and its predictor. This is a cross-sectional observational study on 100 patients with coronary artery disease (CAD) who underwent IVUS-guided PCI with a pullback to LM in Dr. Hasan Sadikin General Hospital Bandung, Indonesia, from January 2020 until December 2022. Linear regression was used to determine the predictors of LM size. There were 100 segments of LM. LM's mean EEM diameter and CSA were 5.02 ± 0.43 mm and 19.93 ± 3.48 mm2. Body surface area (BSA) is an independent predictor of EEM diameter and CSA with a positive linear relationship (p 0.001 and p 0.0001). Hypertension is an independent predictor of EEM diameter with a positive linear relationship (p 0.034). The linear equation to predict EEM diameter and CSA were (2.741 + 1.272BSA(m2) + 0.165 hypertension (yes)) and (2.745 + 9.601BSA(m2)), respectively. The LM coronary artery size of the Southeast Asian population was comparable with the previous studies. BSA and hypertension are independent predictors of EEM diameter, with BSA being stronger than hypertension. Neither sex nor other cardiovascular risk factors affect the LM size. The knowledge of coronary artery size will help the clinician have a reference for intervention, especially when no intravascular imaging is available.

Implantation of a fully magnetically levitated left ventricular assist device to a 3-year-old patient with body surface area of 0.57 m2.

Postoperative 3D thorax computed tomographic scan image of the patient.

Predicting the 10-year incidence of dyslipidemia based on novel anthropometric indices, using data mining.

BACKGROUND: The aim was to establish a 10-year dyslipidemia incidence model, investigating novel anthropometric indices using exploratory regression and data mining. METHODS: This data mining study was conducted on people who were diagnosed with dyslipidemia in phase 2 (n = 1097) of the Mashhad Stroke and Heart Atherosclerotic Disorder (MASHAD) study, who were compared with healthy people in this phase (n = 679). The association of dyslipidemia with several novel anthropometric indices including Conicity Index (C-Index), Body Roundness Index (BRI), Visceral Adiposity Index (VAI), Lipid Accumulation Product (LAP), Abdominal Volume Index (AVI), Weight-Adjusted-Waist Index (WWI), A Body Shape Index (ABSI), Body Mass Index (BMI), Body Adiposity Index (BAI) and Body Surface Area (BSA) was evaluated. Logistic Regression (LR) and Decision Tree (DT) analysis were utilized to evaluate the association. The accuracy, sensitivity, and specificity of DT were assessed through the performance of a Receiver Operating Characteristic (ROC) curve using R software. RESULTS: A total of 1776 subjects without dyslipidemia during phase 1 were followed up in phase 2 and enrolled into the current study. The AUC of models A and B were 0.69 and 0.63 among subjects with dyslipidemia, respectively. VAI has been identified as a significant predictor of dyslipidemias (OR: 2.81, (95% CI: 2.07, 3.81)) in all models. Moreover, the DT showed that VAI followed by BMI and LAP were the most critical variables in predicting dyslipidemia incidence. CONCLUSIONS: Based on the results, model A had an acceptable performance for predicting 10 years of dyslipidemia incidence. Furthermore, the VAI, BMI, and LAP were the principal anthropometric factors for predicting dyslipidemia incidence by LR and DT models.

The impact of obesity on body surface area adjusted estimated glomerular filtration rate in patients with chronic kidney disease.

BACKGROUND: Assessment of kidney function is necessary for prescribing renally excreted drugs. The estimated glomerular filtration rate (eGFR) routinely reported by laboratories is indexed to a body surface area (BSA) of 1.73 m2. In obese patients, the indexed eGFR may underestimate directly measured GFR. AIMS: To determine the prevalence of obesity in patients with chronic kidney disease (CKD) and examine the effect of adjusting the indexed eGFR for patient BSA (deindexing) across CKD Stages 2-5. METHODS: We conducted a cross-sectional study of 575 adults with stable CKD from two general nephrology clinics over 6 months. Dialysis and kidney transplant patients were excluded. We used four equations (Mosteller, Dubois, Haycock and Schlich) to determine BSA based on actual body weight and applied Bland-Altman plots and piecewise linear regression to examine the relationship between deindexed and indexed eGFR. RESULTS: The median age was 68 years (58% male). The prevalence of overweight and obesity was 31% and 47% respectively. Mean body mass index was 29.7 kg/m2. The Schlich equation for BSA produced the smallest adjustment in eGFR, while the Haycock equation produced the largest adjustment. Males experienced the largest change in eGFR from deindexing because of larger BSAs. Although bias became increasingly positive with higher eGFR, the linear regression stratified by CKD stage indicated that deindexing had little impact with eGFR <45 mL/min/1.73 m2. CONCLUSIONS: In CKD, deindexing the Chronic Kidney Disease Epidemiology Collaboration eGFR may not be necessary when the eGFR is <45 mL/min/1.73 m2, particularly if the patient is female.

Sex bias in prediction and diagnosis of cardiac surgery associated acute kidney injury.

BACKGROUND: Female sex has been recognized as a risk factor for cardiac surgery associated acute kidney injury (CS-AKI). The current study sought to evaluate whether female sex is a risk factor for CS-AKI, or modifies the association of peri-operative change in serum creatinine with CS-AKI. METHODS: Observational study of adult patients undergoing cardiac surgery between 2000 and 2019 in a single U.S. center. The main variable of interest was registered patient sex, identified from electronic medical records. The main outcome was CS-AKI within 2 weeks of surgery. RESULTS: Of 58526 patients, 19353 (33%) were female; 12934 (22%) incurred AKI based on ≥ 0.3 mg/dL or ≥ 50% rise in serum creatinine (any AKI), 3320 (5.7%) had moderate to severe AKI, and 1018 (1.7%) required dialysis within 2 weeks of surgery. Female sex was associated with higher risk for AKI in models that were based on preoperative serum creatinine (OR, 1.35; 95% CI, 1.29-1.42), and lower risk with the use of estimated glomerular filtration, (OR, 0.90; 95% CI, 0.86-0.95). The risk for moderate to severe CS-AKI for a given immediate peri-operative change in serum creatinine was higher in female compared to male patients (p < .0001 and p < .0001 for non-linearity), and the association was modified by pre-operative kidney function (p < .0001 for interaction). CONCLUSIONS: The association of patient sex with CS-AKI and its direction was dependent on the operational definition of pre-operative kidney function, and differential outcome misclassification due to AKI defined by absolute change in serum creatinine.

New limits proposed for the management of non-mutagenic impurities.

Multiple international guidelines exist that describe both quality and safety considerations for the control of the broad spectrum of impurities inherent to drug substance and product manufacturing processes. However, regarding non-mutagenic impurities (NMI) the most relevant ICH Q3A/B guidelines are not applicable during early phases of drug development leading to confusion about acceptable limits at this stage. Thus, there is need for more flexible approaches that ensure that patient safety remains paramount, while taking into consideration the limited duration of exposure. An EFPIA survey, which collected quantitative data from different types of studies applied to qualify impurities in accordance with ICH Q3A, shows that no toxicities could be attributed to any of the 467 impurities at any tested level in vivo. This data combined with earlier published toxicological datasets encompassing drug substances and intermediates, food related substances and chemicals provide convincing evidence that for NMIs, the application of a generic 5 mg/day limit for an exposure duration <6 months, and a 1 mg/day generic limit for life-long exposure, provides sufficient margins to ensure patient safety. Hence, application of these absolute limits to trigger qualification studies (instead of the relative limits described in Q3A/B), is considered warranted. This approach will prevent conduct of unnecessary dedicated impurity qualification studies and the resulting use of animals.

The Clinical Significance of Unplanned Coronary Artery Bypass Grafting in Aortic Root Replacement.

OBJECTIVES: Unexpected coronary artery bypass grafting (CABG) is occasionally required during aortic root replacement (ARR). However, the impact of unplanned CABG remains unknown. DESIGN: A single-center, retrospective observational study. SETTING: At university-affiliated tertiary hospital. PARTICIPANTS: All patients who underwent ARR from 2011 through 2022. INTERVENTIONS: Aortic root replacement with or without unplanned CABG. MEASUREMENTS AND MAIN RESULTS: A total of 795 patients underwent ARR. Among them, 131 (16.5%) underwent planned concomitant CABG, and 34 (4.3%) required unplanned CABG. The most common indication of unplanned CABG was ventricular dysfunction (33.3%), followed by disease pathology (25.6%), anatomy (15.4%), and surgical complications (10.3%). A vein graft to the right coronary artery was the most commonly performed bypass. Infective endocarditis and aortic dissection were observed in 27.8% and 12.8%, respectively. Prior cardiac surgery was seen in 40.3%. The median follow-up period was 4.3 years. Unplanned CABG was not associated with operative mortality (odds ratio [OR] 1.54, 95% CI 0.33-7.16, p = 0.58) or long-term mortality (hazard ratio 0.91, 95% CI 0.44-1.89, p = 0.81). Body surface area smaller than 1.7 was independently associated with an increased risk of unplanned CABG (OR 4.51, 95% CI 1.85-11.0, p < 0.001). CONCLUSIONS: Unplanned CABG occurred in 4.3% of patients during ARR, but was not associated with operative mortality or long-term mortality. A small body surface area was a factor associated with unplanned CABG.

In-person validation of the Ichthyosis Scoring System.

BACKGROUND: Ichthyoses are a heterogeneous group of skin disorders characterized by scaling and erythema. Recognizing the variability of scale and erythema by region and ichthyosis subtype, we developed the Ichthyosis Scoring System (ISS) to quantify severity. We previously found ISS to have high inter- and intrarater reliability in evaluating photographic images. To confirm ISS clinical utility, we examined its performance at the 2022 Foundation for Ichthyosis and Related Skin Types conference. METHODS: Sixty-five participants were evaluated by 3 of 9 medical professionals trained to score ichthyosis scale and erythema using ISS. Intrarater and interrater intraclass correlation coefficients (ICC) were analyzed using one-way and two-way random effects models, respectively. RESULTS: Intrarater reliability was excellent (ICC = 0.931, 95% CI, 0.921-0.940) for scale and good (ICC = 0.876, 95% CI, 0.853-0.899) for erythema scoring. Compared to photo validation with excellent intrarater reliability ratings for both scale (ICC = 0.956, 95% CI, 0.925-0.974) and erythema (ICC = 0.913, 95% CI, 0.855-0.949), ISS demonstrated equivalent reliability for live use. Overall interrater reliability for 10 body sites showed excellent (ICC >0.9) and good (ICC >0.75) agreement and consistency for both scale and erythema. Palms were an exception, demonstrating moderate (ICC >0.5) interrater agreement and consistency for erythema evaluation. CONCLUSIONS: ISS is a reliable measure of global and regional ichthyosis severity during in-person evaluations. Ease-of-use, accessibility, and content validity in both live and photographic evaluation endorse ISS as a standard for ichthyosis severity analysis.

High Ferritin Is Not Needed in Hemodialysis Patients: A Retrospective Study of Total Body Iron and Oral Iron Replacement Therapy.

In vivo iron levels can be adjusted through intestinal iron absorption to be maintained at a suitable level; however, optimal iron levels in hemodialysis (HD) patients are unclear. In this study, we investigated total body iron (TBI), calculated as the sum of red blood cell (RBC) iron and iron stores, during courses of low-dose oral iron replacement therapy, and evaluated in vivo iron sufficiency and its indicators in HD patients. We analyzed data on 105 courses of low-dose iron replacement therapy administered to 83 patients on maintenance HD over 7 months. We evaluated changes in TBI, RBC iron, and iron stores from the initiation of treatment to month 7 in two groups of patients, namely, iron-therapy responders and non-responders. TBI showed significant increases until month 4 and plateaued thereafter in iron-therapy responders, and tended to increase and then reached a similar plateau in non-responders (month 7: 1900 ± 447 vs. 1900 ± 408 mg). Steady-state TBI was strongly correlated with body surface area (y = 1628.6x - 791.91, R2 = 0.88, p < 0.001). We observed constant TBI during oral iron replacement therapy suggesting the activation of a "mucosal block". The results suggest that body surface area has utility for estimating the required TBI with regression equations.

Body surface area compared to body weight dosing of valganciclovir is associated with increased toxicity in pediatric solid organ transplantation recipients.

Optimal dosing of valganciclovir (VGCV) for cytomegalovirus (CMV) prevention in pediatric solid organ transplantation recipients (SOTR) is controversial. Dosing calculated based on body surface area (BSA) and creatinine clearance is recommended but simplified body weight (BW) dosing is often prescribed. We conducted a retrospective 6-center study to compare safety and efficacy of these strategies in the first-year posttransplant There were 100 (24.2%) pediatric SOTR treated with BSA and 312 (75.7%) with BW dosing. CMV DNAemia was documented in 31.0% vs 23.4% (P = .1) at any time during the first year and breakthrough DNAemia in 16% vs 12.2% (P = .3) of pediatric SOTR receiving BSA vs BW dosing, respectively. However, neutropenia (50% vs 29.3%, P <.001), lymphopenia (51% vs 15.0%, P <.001), and acute kidney injury causing treatment modification (8.0% vs 1.8%, P <.001) were documented more frequently during prophylaxis in pediatric SOTR receiving BSA vs BW dosing. The adjusted odds ratio of VGCV-attributed toxicities comparing BSA and BW dosing was 2.3 (95% confidence interval [CI], 1.4-3.7] for neutropenia, 7.0 (95% CI, 3.9-12.4) for lymphopenia, and 4.6 (95% CI, 2.2-9.3) for premature discontinuation or dose reduction of VGCV, respectively. Results demonstrate that BW dosing is associated with significantly less toxicity without any increase in CMV DNAemia.

Risk Factors of Capecitabine-Induced Hand-Foot Syndrome: A Single-Institution, Retrospective Study.

INTRODUCTION: This retrospective study was conducted to identify risk factors for developing hand-foot syndrome (HFS) and to determine new strategies for improving quality of life (QoL) in patients undergoing chemotherapy. METHODS: Between April 2014 and August 2018, we enrolled 165 cancer patients at our outpatient chemotherapy center who were undergoing capecitabine chemotherapy. Variables related to the development of HFS were extracted from the clinical records of patients for use in regression analysis. HFS severity was assessed at the time of completing capecitabine chemotherapy. The degree of HFS was classified in accordance with the National Cancer Institute Common Terminology Criteria for Adverse Events version 5. Multivariate ordered logistic regression analysis was performed to identify risk factors for the development of HFS. RESULTS: Risk factors for the development of HFS included concomitant use of a renin-angiotensin system (RAS) inhibitor (odds ratio [OR] = 2.85, 95% confidence interval [CI] = 1.20-6.79; p = 0.018), body surface area (BSA) (high) (OR = 12.7, 95% CI = 2.29-70.94; p = 0.004), and albumin (low) (OR = 0.44, 95% CI = 0.20-0.96; p = 0.040). DISCUSSION/CONCLUSION: Concomitant use of RAS inhibitor, high BSA, and low albumin were identified as risk factors for the development of HFS. The identification of potential risk factors of HFS may assist in the development of strategies that can be used to improve QoL in patients receiving chemotherapy regimens that include capecitabine.

Size-mismatched transplantation from large donors to small recipients is associated with pancreas graft thrombosis: A retrospective national observational study.

INTRODUCTION: Donor-recipient (D/R) size mismatch has been evaluated for a number of organs but not for pancreas transplantation. METHODS: We retrospectively evaluated 438 patients who had undergone pancreas transplantation. The D/R body surface area (BSA) ratio was calculated, and the relationship between the ratio and graft prognosis was evaluated. We divided the patients into two groups and evaluated graft survival. The incidence of pancreas graft thrombosis resulting in graft failure within 14 days and 1-year graft survival were compared using Kaplan-Meier curves, and the prognostic factors associated with graft thrombosis were identified by univariate and multivariate analyses. RESULTS: The mean/median donor and recipient BSAs were 1.63 m2 /1.65 m2 , and 1.57 m2 /1.55 m2 , respectively; the mean and median D/R BSAs were both 1.05. The receiver operating characteristic curve cutoff for the D/R BSA ratio was 1.09, and significant differences were identified between patients with ratios of ≥1.09 (high group) versus <1.09 (low group). The incidence of graft thrombosis resulting in pancreas graft failure within 14 days was significantly higher in the high group than in the low group (p < .01). One-year overall and death-censored pancreas graft survival were significantly higher in the low group than in the high group (p < .01). Multivariate analysis identified recipient height, donor BSA, and donor hemoglobin A1c as significant independent factors for graft thrombosis. Cubic spline curve analysis indicated an increased risk of graft thrombosis with increasing D/R BSA ratio. CONCLUSION: D/R size mismatch is associated with graft thrombosis after pancreas transplantation.

Impact of body size on efficacy of high-dose dual therapy for Helicobacter pylori eradication.

BACKGROUND: High-dose dual therapy (HDDT) is an emerging and promising therapeutic regime for Helicobacter pylori (H. pylori) eradication. However, the pharmacokinetics of the components of HDDT, amoxicillin and proton pump inhibitor, are likely to be affected by body size. In this study, we aimed to find out the impact of body size on the efficacy of HDDT. METHODS: We collected the medical data of 385 treatment-naive patients infected with H. pylori who received HDDT (esomeprazole 20 mg and amoxicillin 750 mg four times daily) for 14 days from July 2020 to December 2021. The associations among the eradication efficacy, adverse events, and variables (sex, age, height, body weight, body mass index (BMI), body surface area (BSA), smoking, drinking, etc.) were analyzed respectively in our study. Among these factors, continuous variables were classified into categorical variables using the cut-off values which were calculated by receiver operating characteristic analysis. RESULTS: The eradication rate of HDDT was 89.9%. There were 55 (14.3%) patients who occurred adverse events during the treatment. Patients with height <170.5 cm, body weight <60.5 kg, BMI <20.55 kg/m2 , BSA <1.69 m2 had a higher eradication rate (92.1% vs. 84.0%, 93.1% vs. 86.8%, 96.0% vs. 87.8%, 93.4% vs. 84.8%, all p < .05). The multivariate analysis showed that BSA ≥1.69 m2 (OR 2.53, 95% CI: 1.28-4.99, p = .007) was the only independent predictor of eradication failure. CONCLUSION: HDDT could achieve better eradication efficacy in patients with small BSA. Clinicians should be aware of the impact of BSA on the H. pylori eradication rate and pay more attention to patients with large BSA.

Prevalence and burden of atopic dermatitis involving the head, neck, face, and hand: A cross sectional study from the TARGET-DERM AD cohort.

BACKGROUND: Atopic dermatitis (AD) is severely burdensome, and there has been poor characterization of any differences in impact based on the area affected. OBJECTIVE: To estimate the prevalence and HRQoL impact of head/face/neck/hand (HFNH) involvement among patients with moderate-to-severe atopic dermatitis. METHODS: All TARGET-DERM AD registry patients with moderate/severe Investigator Global Assessment (vIGA-AD) were assessed using the Patient Oriented SCORing Atopic Dermatitis, Patient Oriented Eczema Measure (POEM) and the (Children's) Dermatology Life Quality Index ((C)DLQI). RESULTS: 541 participants met the criteria (75.0% adults) and 84% (N = 453) reported HFNH involvement. HFNH and non-HFNH involved participants had similar characteristics; 55.2% female and 46.9% White. Compared to the non-HFNH involved, the involved had severe vIGA-AD (28.5% vs 16.3%, P = .02) and higher median body surface area affected (15% vs 10%, P ≤ .01) and were twice as likely to have higher (C)DLQI and POEM scores. LIMITATIONS: This was an analysis of real-world and patient reported outcome data. CONCLUSION: Real-world HFNH involved AD patients were associated with significantly worse quality of life, POEM/(C)DLQI, and more severe disease. Detailed assessments of specific areas affected by AD are needed to personalize treatment.

Pediatric renal transplantation-A UNOS database analysis of donor-recipient size mismatch.

BACKGROUND: We used the BSAi (Donor BSA/Recipient BSA) to assess whether transplanting a small or large kidney into a pediatric recipient relative to his/her size influences renal transplant outcomes. METHODS: We included 14 322 single-kidney transplants in pediatric recipients (0-17 years old) (01/2000-02/2020) from the United Network for Organ Sharing database. We divided cases into four BSAi groups (BSAi ≤ 1, 1 < BSAi ≤ 2, 2 < BSAi ≤ 3, BSAi > 3). RESULTS: There were no differences concerning delayed graft function (DGF) or primary non-function (PNF) rates, whether the grafts were from living or brain-dead donors. In both transplants coming from living donors and brain-dead donors, cases with BSAi > 3 and cases with 2 < BSAi ≤ 3 had similar graft survival (p = .13 for transplants from living donors, p = .413 for transplants from brain-dead donors), and both groups had longer graft survival than cases with 1 < BSAi ≤ 2 and cases with BSAi ≤ 1 (p < .001). The difference in 10-year graft survival rates between cases with BSAi > 3 and cases with BSAi ≤ 1 reached around 25% in both donor types. The better graft survival in transplants with BSAi > 2 was confirmed in multivariable analysis. CONCLUSIONS: There is no significant impact of donor-recipient size mismatch on DGF and PNF rates in pediatric renal transplants. However, graft survival is significantly improved when the donor's size is more than twice the pediatric recipient's size.

Kidney length normative values - new percentiles by age and body surface area in Central European children and adolescents.

BACKGROUND: Kidney size evaluation is an essential examination in pediatric nephrology. While body length/height is the best predictor of kidney length, age-based and body surface area (BSA)-based normative values may be useful in clinical practice or research. This study aimed to establish ultrasound-based kidney length lambda-mu-sigma (LMS) percentiles by age and BSA in healthy children. METHODS: In 1758 Polish and Lithuanian children (868 boys, 49%) aged 0-19 years, kidney length was measured using ultrasonography. In all participants, anthropometric measurements were taken and kidney function was evaluated based on serum creatinine concentration. Participants with chronic or kidney diseases, abnormal kidney function, or pathologies in sonographic examination were excluded from the analysis. RESULTS: Kidney length (median kidney length) increased progressively from infancy to the age of 18 years, from 60.1 to 114.2 mm in males, and from 57.3 to 105.2 mm in females. A gradual increase of kidney length (50th percentile) in relation to BSA (from 46.1 mm in infants with a BSA of 0-1.2 m2 to 118.3 mm in adolescents with a BSA of 2.6-2.8 m2) was also observed. LMS percentiles by age (stratified by sex) and BSA were determined and presented as graphs and tables of percentiles and LMS parameters by 1-year age intervals and 0.2 m2 of BSA, respectively. CONCLUSIONS: We present the first age- and BSA-based kidney length LMS normative values based on the largest pediatric cohort to date, which can be used in both clinical practice and research studies. A higher resolution version of the Graphical abstract is available as Supplementary information.

Body surface area-based kidney length percentiles misdiagnose small kidneys in children with overweight/obesity.

BACKGROUND: We evaluated the diagnostic performance of height-, age- and body surface area (BSA)-based kidney length (KL) percentiles in the identification of at least one small kidney (KL < 3rd) and in the prediction of reduced estimated glomerular filtration rate (eGFR) and/or elevated blood pressure (BP) in children with and without overweight (OW)/obesity(OB). METHODS: In this cross-sectional study, 744 apparently healthy children (mean age 8.3 years) were recruited in a primary care setting. Clinical data were collected, and serum creatinine and KL were measured. Height-, age- and BSA-based percentiles of KL were calculated and the association of at least one small kidney per subject with reduced eGFR and/or elevated BP was explored by logistic regression. RESULTS: Two hundred fifty-seven out of seven hundred forty-four (34.5%) subjects were OW/OB and 127 (17.1%) had reduced eGFR or elevated BP. In separate analyses in children with OW/OB, the KL percentiles calculated on the basis of BSA were lower compared with height- and age-based KL percentiles. Consequently, the prevalence of a small kidney was significantly higher when evaluating percentiles of KL based on BSA compared with other percentiles. In logistic regression analysis, a small kidney was significantly associated with reduced eGFR and/or elevated BP only when using height-based KL percentiles. The KL percentiles according to BSA for the ideal weight (iBSA) showed similar performance compared with height-based percentiles. No differences in the diagnostic performance of different percentiles were found in children with normal weight. CONCLUSIONS: BSA-based percentiles underestimate KL in children with OW/OB. In these subjects, the use of height-based or iBSA-based percentiles should be preferred. A higher resolution version of the Graphical abstract is available as Supplementary information.

Effect of indexed glomerular filtration rate according to age.

BACKGROUND: To find out up to what age there is dispersion in glomerular filtration rate (GFR) values when normalised by body surface area (BSA) and extracellular fluid volume (ECFV), based on the hypothesis that these values differ in childhood age. METHODS: A retrospective study was performed on patients aged 0-85 years, with renal pathology, who were administered i.v. 51Cr-EDTA. GFR was obtained using the Ham and Piepsz (children) or Christensen and Groth (adults) formula. Results were normalised by BSA and ECFV. RESULTS: The cut-off point is defined as the age that discriminates between values ± 10 points apart. Using a ROC curve analysis, this age was set at 11.96 years with a sensitivity of 0.83 and a specificity of 0.85. The area obtained was 0.902 (95%CI 0.880-0.923). The results were corroborated by linear regression stratifying by age. For children under 12 years of age, the Pearson correlation was 0.883 (95% CI 0.860-0.902). For those aged 12 years or older, this coefficient was 0.963 (95%CI 0.957-0.968). According to our results, when normalising GFR by BSA and by ECFV there are different behaviours according to age. CONCLUSION: For children older than 12 years both normalisation methods can be used, but for children younger than 12 years there are differences. We believe that in children under 12 years of age, GFR should be normalised by ECFV.

Body surface area is a predictor of maturity status in school children and adolescents.

BACKGROUND: Generally, Body surface area (BSA) changes significantly during growth and maturation. These increases portend a possible relationship between body size as determined by BSA with maturational status in children and adolescents. OBJECTIVE: To determine the relationship between maturity status (MS) obtained by non-invasive anthropometric methods and body surface area (BSA) in children and adolescents of both sexes in a regional population of Chile. Additionally, we sought to verify the type of linear or nonlinear relationship between MS and BSA in both sexes. METHODS: A descriptive (cross-sectional) study was designed in 950 children and adolescents of both sexes (539 males and 411 females). The age range ranged from 6.0 to 17.9 years. Anthropometric measurements were evaluated: body weight, standing height, sitting height. MS was assessed by means of two non-invasive anthropometric techniques. Both techniques predict peak years of growth velocity (APHV) through a regression equation for each sex. BSA (m2) was estimated by means of the Haycock equation. RESULTS: The R2 in the linear model is relatively lower (R2 = 0.80 to 0.89 in males and 0.74 to 0.66 in females) in relation to the nonlinear quadratic model (R2 = 0.81 in males and 0.76 to 0.69). The quadratic nonlinear quadratic model reflected an adequate fit (RMSE) for the data set, being in men (RMSE = 1.080 and 1.125), while in women (RMSE = 1.779 and 1.479). CONCLUSION: BSA is positively associated with MS determined by two non-invasive methods in Chilean children and adolescents: The nonlinear quadratic model was a better fit to the data distribution. The results suggest the use of BSA as a possible predictor of maturity status in Chilean youth.