Esther Y. Yoon

Diagnosis of diabetes using hemoglobin A1c: Should recommendations in adults be extrapolated to adolescents?

OBJECTIVE To compare test performance of hemoglobin A1c (HbA1c) for detecting diabetes mellitus/pre-diabetes for adolescents versus adults in the United States. STUDY DESIGN Individuals were defined as having diabetes mellitus (fasting plasma glucose [FPG] ≥ 126 mg/dL; 2-hour plasma glucose (2-hr PG) ≥ 200 mg/dL) or pre-diabetes (100 ≤ FPG < 126 mg/dL; 140 ≤ 2-hr PG < 200 mg/dL. HbA1c test performance was evaluated with receiver operator characteristic (ROC) analyses. RESULTS Few adolescents had undiagnosed diabetes mellitus (n = 4). When assessing FPG to detect diabetes, an HbA1c of 6.5% had sensitivity rates of 75.0% (30.1% to 95.4%) and 53.8% (47.4% to 60.0%) and specificity rates of 99.9% (99.5% to 100.0%) and 99.5% (99.3% to 99.6%) for adolescents and adults, respectively. Additionally, when assessing FPG to detect diabetes mellitus, an HbA1c of 5.7% had sensitivity rates of 5.0% (2.6% to 9.2%) and 23.1% (21.3% to 25.0%) and specificity rates of 98.3% (97.2% to 98.9%) and 91.1% (90.3% to 91.9%) for adolescents and adults, respectively. ROC analyses suggested that HbA1c is a poorer predictor of diabetes mellitus (area under the curve, 0.88 versus 0.93) and pre-diabetes (FPG area under the curve 0.61 versus 0.74) for adolescents compared with adults. Performance was poor regardless of whether FPG or 2-hr PG measurements were used. CONCLUSIONS Use of HbA1c for diagnosis of diabetes mellitus and pre-diabetes in adolescents may be premature, until information from more definitive studies is available.

Antihypertensive Prescribing Patterns for Adolescents With Primary Hypertension

Background: Hypertension is an increasingly common problem in adolescents yet current medical management of primary hypertension in adolescents has not been well-described. Methods: We identified adolescents with primary hypertension by International Classification of Diseases, Ninth Revision codes and looked at prescription patterns chronologically for antihypertensive drug class prescribed and the specialty of prescribing physician. We also examined patient demographics and presence of obesity-related comorbidities. Results: During 2003–2008, there were 4296 adolescents with primary hypertension (HTN); 66% were boys; 73% were aged 11 to 14 years; 53% were black, 41% white, and 4% Hispanic; and 48% had obesity-related comorbidity. Twenty-three percent (977) received antihypertensive prescription. White subjects (odds ratio [OR]: 1.61; confidence interval [CI]: 1.39–1.88), older adolescents (≥15 years, OR: 2.11; CI: 1.79–2.48), and those with comorbidity (OR: 1.57; CI: 1.36–1.82) were more likely to receive antihypertensive prescriptions controlling for gender and years of Medicaid eligibility in logistic regression. Angiotensin converting enzyme inhibitors were the most frequently prescribed monotherapy. Nearly two-thirds of adolescents received prescriptions from adult primary care physicians (PCPs) only. More than one-quarter of adolescents who received a prescription received combination therapy, which was most often prescribed by adult PCPs. Conclusions: Adult PCPs were the leading prescribers of antihypertensives for adolescents with primary HTN. Race differences exist in physicians’ prescribing of antihypertensives to adolescents with primary HTN. The choice of antihypertensives by physicians of different specialties warrants additional study to understand the underlying rationale for treatment decisions and to determine treatment effectiveness.

Factors Associated with Non-Attendance at Pediatric Subspecialty Asthma Clinics

Background. Children with Medicaid insurance are less likely to receive subspecialty asthma care than non-Medicaid patients. However, it is not clear if such disparities are due to non-attendance at scheduled visits by patients. Objective. To determine factors associated with non-attendance at scheduled visits for pediatric subspecialty asthma care. Design/Methods. We conducted a cross-sectional study of children with scheduled visits at three asthma clinics during a 12-month period. Our outcome of interest was patient non-attendance for a scheduled visit, controlling for age, gender, new patient status, type of insurance, severity of illness, distance to clinic, clinic site, month, and weekday of scheduled visit. We used logistic regression for multivariate comparisons and controlled for clustering effects for children with multiple scheduled visits. Results. There were 1236 scheduled visits for 857 unique patients. Median age: 7 years (IQR 3–11); median distance traveled: 24 miles (IQR 13–41); 20% had Medicaid insurance. The non-attendance rate was 8%. In multivariate analysis, Medicaid insurance (OR 2.33, 95% CI 1.45–3.74) and visits scheduled in September–December (3.26, 2.08–5.11) were associated with non-attendance. Conclusions. Children with Medicaid insurance are less likely to attend scheduled visits for subspecialty asthma care, controlling for seasonal variation. Programs designed to address disparities in pediatric asthma outcomes regarding subspecialist care may improve their effectiveness by addressing barriers to attendance and anticipating poor attendance in the fall season.

FDA Labeling Status of Pediatric Medications

Prior studies suggest that approximately 75% of prescription medications listed in the Physician’s Desk Reference (PDR) lack pediatric labeling.1-5 Lack of pediatric labeling may be problematic for physicians, who must decide either to treat children based on adult studies or anecdotal experience in children or not to treat with potentially beneficial medications.3 Treating children based on extrapolations from adult studies can potentially result in ineffective therapy due to underdosing of medications or adverse effects attributable to overdosing. For instance, gabapentin must be given at higher doses in children younger than 5 years of age to effectively control seizures.6 On the other hand, use of chloramphenicol in newborns results in graybaby syndrome, because newborns lack the necessary enzyme in the liver to metabolize chloramphenicol thereby resulting in toxic accumulations of the medication.6 Although some physicians may choose not to treat children based on adult studies or anecdotal experience to avoid lack of efficacy or adverse effects, such choices may also deprive children of potentially therapeutic medications. In the face of this clinical dilemma, we are unaware of any study that has systematically assessed the pediatric labeling status of medications currently available for pediatric use. The purpose of this study was to describe the pediatric labeling status of medications listed in the Harriet Lane Handbook, 16th edition (2002), a commonly used source of information about medications in pediatric practice. Methods

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.

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.

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.

Parental Preferences for FDA-Approved Medications Prescribed for Their Children

Objective. To describe parental preferences for FDA-approved prescription medications for their children. Study design. Cross-sectional Web-enabled survey of a national sample of 1562 parents. Results. Response rate was 61%. Most parents (77%) preferred prescription of only FDA-approved medications for their child. However, one half of parents preferred that their child’s doctor prescribe medication that is safest and works best, even if not FDA approved for children. One third of parents (34%) preferred nothing but FDA-approved medications for their child, regardless of drug safety, effectiveness, or cost. Controlling for parent race and education, mothers (odds ratio = 1.52; P = .004) and older parents (odds ratio = 1.60; P = .025) were more likely to prefer nothing but FDA-approved medications for their children compared with fathers and younger parents. Conclusions. Although most parents initially indicate preference for FDA-approved medications, one half of parents will accept a non-FDA-approved medication for their children with the understanding that it is safer or more effective than the FDA-approved alternative.

Variation in Pediatric Asthma Quality Improvement Programs by Managed Care Plans

Although asthma quality improvement (QI) programs are common, little is known about the scope and content of QI initiatives in managed care arrangements. The authors conducted a cross-sectional survey of all managed care plans in Michigan serving the pediatric Medicaid population. Using semi-structured interviews, they assessed the comprehensiveness of the asthma QI program regarding provider, allied health professional, pharmacy, and member services. Although all QI initiatives included some type of physician-directed component and patient-directed components, only half included allied health professionals and one quarter included pharmacy-directed components. Interactive physician continuing medical education was associated with plans whose members were concentrated in only 1 or 2 counties. The authors noted wide variation in content, format, inclusion of incentives, inclusion of other health professionals, and outcome goals. The variation in QI approaches by each of the managed care organizations suggests that there is a dearth of information on appropriate and cost-effective methods to improve pediatric asthma quality at the plan level.

Differences in Blood Pressure Monitoring for Children and Adolescents With Hypertension Among Pediatric Cardiologists and Pediatric Nephrologists

Hypertension is a common chronic condition in children and adolescents with prevalence estimates of 5%. Children with primary or secondary hypertension are managed primarily in the subspecialty domain by pediatric cardiologists or nephrologists. Prior work has described specialty differences in the use of antihypertensive medications and diagnostic tests for children and adolescents with primary hypertension. However, physicians’ approach to blood pressure (BP) monitoring for children and adolescents with hypertension has not been previously investigated. Pediatric cardiologists and pediatric nephrologists may differ in their use of blood pressure monitoring. Pediatric hypertension guidelines recommend ambulatory blood pressure monitoring (ABPM), where a portable BP monitor is placed on a patient’s upper arm and when the ABPM device is returned to the clinic, data are downloaded and interpreted by trained clinic personnel. ABPM is the recommended method in the evaluation of masked, white coat, and nocturnal hypertension and to assess cardiovascular disease (CVD) risk in patients with hypertension and chronic kidney disease. In contrast, home blood pressure monitoring (HBPM) is a long-term program of self-monitoring BP at home that is widely recommended and successfully used to track BP trajectory in adult patients with known or suspected hypertension. Importantly, differences in BP monitoring by subspecialists have potential implications for patient outcomes. The purpose of this study was to quantify the use of outof-clinic blood pressure monitoring for children and adolescents with hypertension by pediatric cardiologists and pediatric nephrologists.