Analysis of inflammatory cytokines in the chest tube drainage of post-operative superior cavopulmonary connection patients.

INTRODUCTION: Prolonged pleural effusions are common post Fontan operation and are associated with morbidity. Fontan pleural effusions have elevated proinflammatory cytokines. Little is known about the chest tube drainage after a superior cavopulmonary connection. We examined the chest tube drainage and the inflammatory profiles in post-operative superior cavopulmonary connection patients. METHODS: This prospective cohort study enrolled 25 patients undergoing superior cavopulmonary connection and 10 age-similar controls. Data are also compared to 25 previously published Fontan patients and their 15 age-similar controls. Chest tube samples were analysed with a 17-cytokine BioPlex Assay. Descriptive statistics and univariate comparisons were made between groups. RESULTS: Duration of chest tube drainage was significantly shorter in superior cavopulmonary connection patients (median 4 days, [interquartile range 3-5 days]) versus Fontan patients (10 days, [7-11 days], p < 0.0001). Cytokine concentrations were higher on post-operative day 1 in superior cavopulmonary connection patients versus Fontan patients (all p ≤ 0.01), however levels were comparable to age-similar controls. While proinflammatory IL 8, MIP-1ß, and TNF-α concentrations increased in chest tube drainage of Fontan patients from post-operative day 1 to last chest tube day (all p < 0.0001), there was no change in these biomarkers in superior cavopulmonary connection patients, their controls, or Fontan controls. CONCLUSIONS: Our study demonstrates that after superior cavopulmonary connection, proinflammatory cytokines in the chest tube drainage remain similar to biventricular controls of both age groups, unlike the significant rise over time observed in Fontan patients. Inflammation within the chest tube drainage is likely not innate to single ventricle patients.

Acute Hemodynamic Effects of Negative Extrathoracic Pressure in Fontan Physiology.

We sought to assess acute hemodynamic changes after implementation of negative extrathoracic pressure (NEP) in spontaneously breathing ambulatory Fontan patients with symptomatic heart failure. We hypothesized that application of NEP would result in an acute decrease in pulmonary artery pressure. Ten patients with clinical evidence of Fontan failure underwent baseline hemodynamic catheterization while breathing spontaneously. Hemodynamic measurements were then repeated after 30 min of continuous NEP. After 30 min of continuous NEP, 4/10 patients had a decrease in their Fontan pressure by 2 mmHg and one patient had a decrease by 1 mmHg. There were three patients that had an increase in Fontan pressure by 2 mmHg. In 7/10 patients, indexed pulmonary vascular resistance decreased by an average of 31%. In symptomatic Fontan patients with a favorable hemodynamic response to NEP during catheterization, potential benefit of longer-term NEP to improve clinical status should be explored.

Analysis of Inflammatory Cytokines in Postoperative Fontan Pleural Drainage.

Prolonged pleural drainage is a common complication in patients after Fontan palliation and is associated with short- and long- term morbidities. Among many potential etiologies, prolonged drainage has an inflammatory component, but there are no descriptions of cytokines in Fontan pleural drainage to date. This study aimed to examine the inflammatory make-up of Fontan pleural drainage. This prospective age-range-matched cohort study recruited 25 patients undergoing Fontan procedure and 15 bi-ventricular patients undergoing cardiopulmonary bypass (CPB). Chest tube samples were taken on postoperative day (POD) 1-4, 7, and 10. Cytokines were measured using Bio-Plex Assays. Univariate comparisons were made in patient characteristics and cytokine levels. Median age was 3.7 y (IQR 2.8-3.9) for controls and 2.5 y (IQR 2.1-2.9) in Fontan patients (p = 0.02). Median drainage duration and daily volume was higher in Fontan patients (both p < 0.001). Inflammatory cytokines (IL-17A, IFN-y, MIP-1ß, and TNF-α) were higher in Fontan patients than controls (all p < 0.02). There was an increase in pro-inflammatory cytokines (IL-8, MIP-1ß, and TNF-α) from POD1 to the last chest tube day (LCD) in Fontan patients (all p < 0.0001) and a decrease in the anti-inflammatory cytokine IL-10 (p = 0.001). There was no difference in cytokine concentration from POD1 to LCD among controls. There was a significant association with the cytokine concentration of TNF-α on POD1 and duration of chest tube drainage (p < 0.05). Inflammatory cytokine levels in the pleural fluid of Fontan patients are higher compared to bi-ventricular controls and rise over time where controls do not. This suggests ongoing localized inflammation that is not a result of CPB alone and may be an important contributor to pleural drainage in patients after the Fontan procedure.

Relation of Increased Epicardial Fat After Fontan Palliation to Cardiac Output and Systemic Ventricular Ejection Fraction.

Epicardial fat produces multiple proinflammatory cytokines and is associated with adverse cardiovascular events. Inflammation and resultant endothelial dysfunction may play a role in progressive myocardial dysfunction among adults with single ventricle physiology after Fontan palliation, but the potential impact of increased epicardial fat volume (EFV) has not been studied. This study sought to determine if there is greater EFV in Fontan patients compared with a group of repaired tetralogy of Fallot (rTOF) patients. We retrospectively measured EFV manually on cardiac magnetic resonance imaging in Fontan patients, ≥15 years, and 1:1 age, sex, and body mass index-matched patients with rTOF. EFV was indexed to body surface area. A random subset of studies was re-measured to assess intra- and interobserver reliability. Fontan patients (n = 63, median age 21.6 years, 51% male, mean body mass index 24.2 ± 5.6 kg/m2) had a larger indexed EFV compared with matched rTOF patients (75.3 ± 29.2 ml/m2 vs 60.0 ± 19.9 ml/m2, p = 0.001). In Fontan patients, indexed EFV was inversely correlated with ventricular ejection fraction (r = -0.26, p = 0.04) and cardiac index (r = -0.33, p = 0.01). Intra- and interobserver reliabilities of the indexed EFV measurements in both groups were excellent (intraclass correlation coefficient ranges from 0.93 to 0.97). In conclusion, indexed EFV is higher in Fontan patients compared with patients with rTOF and is associated with lower ventricular ejection fraction and cardiac index. Increased EFV could play a role in the failing Fontan circulation, but longitudinal studies are necessary to establish any causative role.

Long-Term Outcomes After Surgical Pulmonary Arterioplasty and Risk Factors for Reintervention.

BACKGROUND: Although surgical patch arterioplasty is the conventional therapy for branch pulmonary artery (PA) stenosis, limited data exist on long-term outcomes. We examined the incidence of and risk factors for reintervention after surgical arterioplasty for branch PA stenosis in biventricular congenital heart disease. METHODS: This retrospective cohort study included patients with 2-ventricle physiology who underwent patch arterioplasty for PA stenosis at a single high-volume congenital heart center during a 10-year period. Freedom from surgical or percutaneous reintervention for recurrent PA stenosis was evaluated. Univariate and multivariable Cox regression analyses were performed to determine risk factors for reintervention. RESULTS: Among 135 patients, the median age at patch arterioplasty was 0.9 years. Survival to hospital discharge (or 30 days postoperatively) was 96%. During a median follow-up period of 4.0 years, reintervention for PA stenosis occurred in 38 of 115 patients (33%) at a median time to reintervention of 1.4 years. The overall 10-year reintervention rate was 54%. In univariate analysis, age less than 30 days at initial arterioplasty, congenital PA stenosis (vs acquired), and bilateral PA stenosis (vs unilateral) were significantly associated with reintervention. In multivariable analysis, neonatal age (adjusted hazard ratio, 3.6; p = 0.002) and bilateral PA stenosis (adjusted hazard ratio, 2.8; p = 0.005) remained independently associated with reintervention. CONCLUSIONS: Long-term reintervention for recurrent PA stenosis after patch arterioplasty is common. Patients with bilateral PA stenosis or age younger than 30 days at the time of the index pulmonary arterioplasty are at higher risk for reintervention. These patients may benefit from frequent monitoring or novel approaches to repair.

Temporal relationship between instantaneous pressure gradients and peak-to-peak systolic ejection gradient in congenital aortic stenosis.

OBJECTIVE: We sought to identify a time during cardiac ejection when the instantaneous pressure gradient (IPG) correlated best, and near unity, with peak-to-peak systolic ejection gradient (PPSG) in patients with congenital aortic stenosis. Noninvasive echocardiographic measurement of IPG has limited correlation with cardiac catheterization measured PPSG across the spectrum of disease severity of congenital aortic stenosis. A major contributor is the observation that these measures are inherently different with a variable relationship dependent on the degree of stenosis. DESIGN: Hemodynamic data from cardiac catheterizations utilizing simultaneous pressure measurements from the left ventricle (LV) and ascending aorta (AAo) in patients with congenital valvar aortic stenosis was retrospectively reviewed over the past 5 years. The cardiac cycle was standardized for all patients using the percentage of total LV ejection time (ET). Instantaneous gradient at 5% intervals of ET were compared to PPSG using linear regression and Bland-Altman analysis. RESULTS: A total of 22 patients underwent catheterization at a median age of 13.7 years (interquartile range [IQR] 10.3-18.0) and median weight of 51.1 kg (IQR 34.2-71.6). The PPSG was 46.5 ± 12.6 mm Hg (mean ± SD) and correlated suboptimally with the maximum and mean IPG. The midsystolic IPG (occurring at 50% of ET) had the strongest correlation with the PPSG ( PPSG = 0.97(IPG50%)-1.12, R2 = 0.88), while the IPG at 55% of ET was closest to unity ( PPSG = 0.997(IPG55%)-1.17, R2 = 0.87). CONCLUSIONS: The commonly measured maximum and mean IPG are suboptimal estimates of the PPSG in congenital aortic stenosis. Using catheter-based data, IPG at 50%-55% of ejection correlates well with PPSG. This may allow for a more accurate estimation of PPSG via noninvasive assessment of IPG.

Twenty years of experience with intraoperative pulmonary artery stenting.

OBJECTIVES: To describe our 20-year experience with intraoperative pulmonary artery (PA) stent placement and evaluate long-term patient outcomes, specifically the need and risk factors for reintervention. BACKGROUND: Intraoperative PA stent placement is an alternative to surgical patch arterioplasty and percutaneous angioplasty or stent placement to treat branch PA stenosis. METHODS: We performed a retrospective review of all intraoperative PA stents placed at our institution from 1994-2013. Patient and stent characteristics and outcome data were collected. Risk factors associated with reintervention were identified using univariate cox regression analysis. RESULTS: Eighty-one PA stents were placed in 68 patients. The procedural complication rate was 4.4%. During a median follow-up period of 6 years (interquartile range [IQR] 0.9-12.7), 30 patients (44%) underwent reintervention on the stented PA with a median time to first reintervention of 2.6 years (IQR 0.7-4.4 years). The first reintervention was surgical in 30% and catheter-based in 70%. Risk factors for reintervention included age < 18 months (Hazard ratio [HR] 2.97, P = 0.005) and body surface area < 0.47 m2 (HR 3.20, P = 0.003) at the time of stent implantation, and the presence of multiple aortopulmonary collaterals in patients with tetralogy of Fallot (HR 4.61, P = 0.003). CONCLUSIONS: Intraoperative PA stent implantation is a safe and effective alternative to percutaneous stent implantation and offers several advantages, including the ability to implant adult-size stents in small patients while avoiding injury to peripheral vessels, to position stents to facilitate future percutaneous stent redilation, and to access the PAs directly, which eliminates radiation exposure. © 2017 Wiley Periodicals, Inc.

Altered Cholesterol Metabolism and Hypocholesterolemia in Patients with Single Ventricle following Fontan Palliation.

OBJECTIVE: To assess whether an abnormality in cholesterol absorption or synthesis may be associated with hypocholesterolemia in patients with single ventricle anatomy following Fontan palliation. STUDY DESIGN: This is a cross-sectional study of 21 patients with hypocholesterolemia following Fontan procedure and age/sex-matched healthy controls, with median age of 13.4 (IQR 10.6-16.1) years. Laboratory values of several biomarkers, including phytosterols and 5-α-cholestanol (for cholesterol absorption) and lathosterol (for cholesterol biosynthesis), as well as cholesterol levels, inflammatory markers, and indices of liver function were compared between patients following Fontan procedure and controls. RESULTS: The Fontan cohort had significantly lower total cholesterol (mean 117 ± SD 13.9, vs 128 ± 19.2 mg/dL, P = .03) and free cholesterol (35.5 ± 4.5 vs 39.2 ± 5.4 mg/dL, P = .02) compared with control patients. There was an increase in normalized 5-α-cholestanol (1.51 ± 0.6 vs 1.14 ± 0.37 µg/mL, P = .02), and a significantly lower lathosterol/5-α-cholestanol ratio (0.70 ± 0.38 vs 1.11 ± 0.76, P = .04). There was a strong correlation (r = 0.78, P < .0001) between lathosterol and cholesterol levels in the Fontan cohort, not seen in controls (r = 0.47, P = .04). The Fontan cohort also had significantly higher C-reactive protein, transaminases, total bilirubin, and gamma-glutamyl transferase levels. CONCLUSIONS: Patients with hypocholesterolemia following Fontan procedure have evidence of increased cholesterol absorption and decreased cholesterol synthesis. As cholesterol absorption efficiency is a regulated process, this finding suggests an upregulation of cholesterol absorption as a result of decreased cholesterol production. In the setting of elevated liver indices and possible inflammation, this finding supports a growing body of data suggesting development of liver disease in patients receiving Fontan.

Pediatric Hypertension Specialists' Perspectives About Adolescent Hypertension Management: Implications for Primary Care Providers.

BACKGROUND: The current specialty-centric hypertension paradigm is unsustainable given the high prevalence of primary hypertension in adolescents. OBJECTIVE: To describe specialists' perspectives on referral and comanagement for adolescents with hypertension. METHODS: Cross-sectional mailed survey of a national sample of 397 pediatric cardiologists and 389 pediatric nephrologists, conducted January to May 2014. RESULTS: Response rate was 61%. Both specialties agreed that primary care providers can make the hypertension diagnosis, try lifestyle changes, and comanage monitoring of patient blood pressure control and medication side effects, but they felt antihypertensive medication use should mainly occur in the specialty setting. CONCLUSIONS: Our study suggests specialist support for changing the hypertension paradigm to encourage primary care providers, in collaboration with specialists, to diagnose hypertension, initiate lifestyle changes, and monitor progress and side effects. Future work should focus on supporting primary care physician comanagement of adolescents with hypertension.

Elective ECMO support for pulmonary artery stent placement in a 4.9-kg shunt-dependent patient.

Although extracorporeal membrane oxygenation (ECMO) is traditionally used to emergently manage respiratory and/or cardiovascular failure, ECMO can also support cardiorespiratory function in nonemergent settings. Here we present the elective use of ECMO to support a 4.9-kg pediatric patient undergoing a complex percutaneous catheter-based intervention.

Obesity and elevated blood pressure following repair of coarctation of the aorta.

OBJECTIVE: To determine whether patients with coarctation of the aorta (COA) were more likely to develop obesity compared with the general population or others with isolated forms of congenital heart disease. STUDY DESIGN: We conducted a cross-sectional study of 160 patients who underwent COA repair at our institution between 1974 and 2009. Body mass index (BMI) measurements were obtained from the most recent clinic visit and at 5, 10, 15, and 20 years of age from retrospective chart review. BMI values were compared against established normal data to obtain age-sex matched z-scores. We also compared the rates of developing obesity over time in adults with COA vs 96 adults with other isolated forms of congenital heart disease, including aortic valve stenosis, pulmonary valve stenosis, or atrial septal defect. RESULTS: After age 5 years, patients with COA had significantly greater BMI z-scores compared with age-sex matched normal data (P < .001). The proportion of obesity in patients with COA significantly increased over time (P < .001). Adults with repaired COA developed obesity at a greater rate than those with either aortic valve stenosis (P = .004) or with pulmonary valve stenosis or atrial septal defect (P < .001). CONCLUSIONS: There is a greater incidence of obesity that progressively increases with age in patients with repaired COA. Adults with repaired COA developed obesity at a greater rate than those with other isolated forms of congenital heart disease. Further prospective trials are needed to confirm our observations and to elucidate the potential mechanism relating COA to obesity.

Use of antihypertensive medications and diagnostic tests among privately insured adolescents and young adults with primary versus secondary hypertension.

PURPOSE: To compare the use of antihypertensive medications and diagnostic tests among adolescents and young adults with primary versus secondary hypertension. METHODS: We conducted retrospective cohort analysis of claims data for adolescents and young adults (12-21 years of age) with ≥3 years of insurance coverage (≥11 months/year) in a large private managed care plan during 2003-2009 with diagnosis of primary hypertension or secondary hypertension. We examined their use of antihypertensive medications and identified demographic characteristics and the presence of obesity-related comorbidities. For the subset receiving antihypertensive medications, we examined their diagnostic test use (echocardiograms, renal ultrasounds, and electrocardiograms). RESULTS: The study sample included 1,232 adolescents and young adults; 84% had primary hypertension and 16% had secondary hypertension. The overall prevalence rate of hypertension was 2.6%. One quarter (28%) with primary hypertension had one or more antihypertensive medications, whereas 65% with secondary hypertension had one or more antihypertensive medications. Leading prescribers of antihypertensives for subjects with primary hypertension were primary care physicians (80%), whereas antihypertensive medications were equally prescribed by primary care physicians (43%) and sub-specialists (37%) for subjects with secondary hypertension. CONCLUSIONS: The predominant hypertension diagnosis among adolescents and young adults is primary hypertension. Antihypertensive medication use was higher among those with secondary hypertension compared with those with primary hypertension. Further study is needed to determine treatment effectiveness and patient outcomes associated with differential treatment patterns used for adolescents and young adults with primary versus secondary hypertension.

Left ventricular function by pressure-volume loop analysis before and after percutaneous repair of large atrial septal defects.

AIM: The intent of the present study was to evaluate changes in ventricular function with percutaneous closure of atrial septal defect (ASD), as it is associated with alterations in ventricular loading and function. Transcatheter occlusion of ASD imparts acute changes in volume loading of the left ventricle (LV) that obscures measurement of ventricular function by load-dependent indices. To differentiate between changes in ventricular loading and function, load-independent indices of ventricular function must be utilized. METHODS: During transcatheter occlusion of ASD, subjects underwent measurement of LV pressure and volume by the conductance catheter method. Load-dependent indices of ventricular function included: systolic and diastolic pressures, +dP/dtmax , and -dP/dtmax . Load-independent indices included: elastance and tau, the preload-independent time constant ofisovolumic relaxation. To obtain elastance, afterload was augmented by phenylephrine bolus pre- and post-device occlusion. RESULTS: In total, 29 patients (age 2-79 years) underwent ASD device occlusion (device size 12-38 mm, median 28 mm). Load-dependent indices were obtained in all, and satisfactory pressure-volume loops in 11. At baseline, LV end-diastolic pressure was 5-23 mmHg (13 ± 5 mmHg) and tau was 31 ± 6 ms. Postclosure of the ASD, LV systolic and diastolic pressures rose by 10 ± 11 mmHg and 5 ± 3 mmHg, respectively (P < 0.05), and +dP/dtmax rose from 1,288 ± 313 mmHg/sec to 1,415 ± 465 mmHg/sec (P < 0.05), but -dP/dtmax was unchanged. Elastance significantly improved (9.4 ± 8.3 mmHg/mL vs. 13.0 ± 7.3 mmHg/mL, P < 0.05) and tau was unchanged. CONCLUSIONS: Transcatheter occlusion of ASD is associated with acute improvement in load-independent indices of systolic function in this cohort, without significant worsening of the preload-independent index of diastolic function.

Low total, low-density lipoprotein, high-density lipoprotein, and non-high-density lipoprotein cholesterol levels in patients with complex congenital heart disease after Fontan palliation.

OBJECTIVE: To test the hypothesis that patients with complex congenital heart disease who have undergone Fontan palliation have low total cholesterol, low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) levels. STUDY DESIGN: We retrospectively reviewed the random serum lipid profiles obtained at cardiology clinic visits between May 2010 and November 2011 in patients who had undergone the Fontan procedure. We compared these serum lipid levels against age- and sex-matched established normal data from the Third National Health and Nutrition Examination Survey. RESULTS: Eighty-eight patients who had undergone the Fontan procedure also had laboratory test data obtained during their visits. Median total cholesterol level in the Fontan group was 127 mg/dL (IQR, 116-144 mg/dL), median HDL-C was 40 mg/dL (IQR, 33-45 mg/dL), median non-HDL-C was 86 mg/dL (IQR, 76-109 mg/dL), and median LDL-C was 66 mg/dL (IQR, 57-83 mg/dL). Total cholesterol, LDL-C, non-HDL-C, and HDL-C levels were significantly lower in patients who had undergone a Fontan procedure compared with age- and sex-matched normal individuals (mean z-score, -1.4, -1.2, -1.0, and -1.0 respectively; all P<.0001). Cholesterol levels were below the 25th percentile for age and sex for total cholesterol in 82% of patients, for LDL-C in 76%, for non-HDL-C in 67%, and for HDL-C in 57%. CONCLUSION: Patients who have undergone the Fontan procedure have significantly lower serum total cholesterol, LDL-C, HDL-C and non-HDL-C levels than age- and sex-matched normal individuals. Although the implications of this finding are unknown, it raises the possibility of abnormalities in cholesterol absorption, synthesis, or catabolism in this patient population.

Underlying Rationale and Approach to Treat Hypertension in Adolescents by Physicians of Different Specialty.

OBJECTIVE: To describe the underlying clinical decision-making rationale among general pediatricians, family physicians, pediatric cardiologists and pediatric nephrologists in their approach to an adolescent with hypertension. METHODS: We conducted semi-structured phone interviews with a convenience sample of physicians from the above-mentioned 4 specialties. Each participant was asked to "think aloud" regarding their approach to a hypothetical patient - 12 year old boy with persistent hypertension for 6 months. Standardized open-ended questions about potential factors that could affect physicians' diagnosis and treatment strategies (e.g., patient age) were used. Interviews were audio-recorded; transcribed verbatim; transcripts were independently coded by 2 investigators; emergent themes identified and inter-coder agreement achieved. Thematic analysis was performed based on grounded theory. RESULTS: Nineteen participants included 5 general pediatricians, 5 pediatric cardiologists, 5 pediatric nephrologists and 4 family physicians. Five themes emerged: 1) Accuracy of blood pressure measurement and hypertension diagnosis, 2) Shift in the epidemiology of pediatric hypertension from secondary to primary hypertension, 3) Patient characteristics considered in the decision to initiate workup, 4) Obesity-centered choice of diagnostic tests and lifestyle modifications, and 5) Variable threshold for initiating antihypertensive pharmacotherapy vs. referral to hypertension specialists. CONCLUSIONS: There is variation across primary care and specialty physicians who provide care for children and adolescents with hypertension. Key areas of variability include the willingness to initiate antihypertensive medications, the use of diagnostic tests (e.g., ambulatory blood pressure monitoring), and the perceived need for specialty referral. Further study is needed to assess whether different treatment paradigms result in differential patient outcomes.

Use of diagnostic tests in adolescents with essential hypertension.

OBJECTIVE: To describe the use of diagnostic tests in adolescents with essential hypertension. DESIGN: Longitudinal analysis of administrative claims data. SETTING: Michigan Medicaid program during 2003 to 2008. PARTICIPANTS: Adolescents with 3 or more years of Medicaid eligibility (≥ 11 months/y) who had a diagnosis of essential hypertension and 1 or more antihypertensive medication pharmacy claims. MAIN OUTCOME MEASURES: We examined adolescents' echocardiogram use and compared it with electrocardiogram (EKG) and renal ultrasonography use. We examined timing of the 3 diagnostic tests in relation to the first pharmacy claim. We examined patient demographics and presence of obesity-related comorbidities. RESULTS: During 2003 to 2008, there were 951 adolescents with essential hypertension who had antihypertensive pharmacy claims; 24% (226) had echocardiograms; 22% (207) had renal ultrasonography; and 50% (478) had EKGs. Males (odds ratio [OR], 1.53; 95% CI, 1.06-2.21), younger adolescents (OR, 1.69; 95% CI, 1.17-2.44), those who had EKGs (OR, 5.79; 95% CI, 4.02-8.36), and those who had renal ultrasonography (OR, 2.22; 95% CI, 1.54-3.20) were more likely to obtain echocardiograms compared with females, older adolescents, and adolescents who did not have EKGs or renal ultrasonography. CONCLUSIONS: Guideline-recommended diagnostic tests-echocardiograms and renal ultrasonography-were equally poorly used by adolescents with essential hypertension. Sex and age differences exist in the use of echocardiograms by adolescents with essential hypertension. The decision and choice of diagnostic tests to evaluate adolescents with essential hypertension warrant further study to understand the underlying rationale for those decisions and to determine treatment effectiveness.

Clonidine utilization trends for Medicaid children.

OBJECTIVE: To characterize clonidine utilization trends among children. DESIGN/METHODS: Serial cross-sectional analysis of Michigan Medicaid claims data for children aged 6 to 18 years. The authors identified children with ≥1 clonidine prescription; the authors examined their ICD-9 diagnoses categorized as simple and complex attention deficit hyperactivity disorder (ADHD), non-ADHD mental health disorder, hypertension, or others. Also identified were child demographics and prescribing physician specialty. RESULTS: From 2003 to 2008, the proportion of children receiving clonidine prescription nearly doubled in all demographics. Across years, the majority of clonidine prescription was for simple and complex ADHD and other mental health disorders. Leading prescribers were psychiatrists followed by general pediatricians and adult primary care physicians. CONCLUSIONS: Clonidine was used extensively to treat simple and complex ADHD in children although FDA approval for this indication did not occur until 2010. Further study is warranted to better understand clinical outcomes and costs associated with clonidine use for the treatment of children with ADHD.