Abstract
OBJECTIVE: Although unnecessary for children with headache and normal history, computed tomography (CT) scans are widely used. This study sought to determine current practice patterns of neuroimaging to diagnose pediatric headache in a variety of treatment settings and to identify factors associated with increased use of neuroimaging.
METHODS: This retrospective claims analysis included children (aged 3–17 years) with ≥2 medical claims for headache. The primary outcome was CT scan utilization on or after first presentation with headache in a physician’s office or emergency department (ED).
RESULTS: Of 15 836 patients, 26% (4034 patients; mean age: 11.8 years) had ≥1 CT scan, 74% within 1 month of index diagnosis. Patients with ED visits were 4 times more likely to undergo a CT scan versus those without ED visits (P < .001 [95% confidence interval: 3.9–4.8]). However, even outside the ED, use of CT scans remained widespread. Two-thirds of patients with CT scans had no ED use. Among patients with no ED utilization, >20% received a CT scan during the study period. Evaluation by a neurologist was strongly associated with a lower likelihood of CT scan compared with other provider specialties (odds ratio: 0.37; P < .01 [95% confidence interval: 0.30–0.46]).
CONCLUSIONS: Use of CT scans to diagnose pediatric headache remains high despite existing guidelines, low diagnostic yield, and high potential risk. Implementing quality improvement initiatives to ensure that CT scans in children are performed only when truly indicated will reduce unnecessary exposure to ionizing radiation and associated cancer risks.
- AAN —
- American Academy of Neurology
- AAP —
- American Academy of Pediatrics
- ACR —
- American College of Radiology
- CI —
- confidence interval
- CT —
- computed tomography
- ED —
- emergency department
What’s Known on This Subject:
Although unnecessary for children with headache and normal history, computed tomography (CT) scans are widely used. Fewer than 1% of pediatric brain abnormalities present with headache as the only symptom. Furthermore, repeated CT scans may increase lifetime risk of cancer.
What This Study Adds:
CT scans continue to be used to diagnose isolated pediatric headaches despite existing practice parameters. Although emergency department visits were correlated with greater likelihood of CT scan use, these scans were widely used across a variety of clinical settings.
Headaches are among the 5 most common health issues in children1,2 as well as 1 of the most frequent reasons for pediatric neuroimaging, particularly in emergency departments (EDs). In 2008, 1.7 million pediatric CT scans were performed in the ED, nearly 6% of all pediatric ED visits that year.3 As many as 28% of those scans were performed for headache unrelated to head injury. Brain tumors are uncommon in children, and <1% of brain abnormalities in children present with headache as the only symptom.1,4 Thus, neuroimaging is considered unnecessary in the diagnosis of headache when no other neurologic symptoms are present to suggest serious intracranial pathology.1,5–13
Not only is neuroimaging clinically unnecessary for children with isolated headache, it is also associated with potential long-term health risks. CT scans involve larger doses of radiation than conventional radiographs14 and have been proposed to increase a child’s lifetime risk of cancer.14–17 For example, a retrospective study by Pearce et al17 suggests that the cumulative ionizing radiation doses from as few as 2 to 3 head CT scans in a child aged <15 years could triple the risk of brain tumors; 5 to 10 head scans could triple the risk of leukemia. It should be noted the occurrence of these cancers is rare, and the cumulative absolute risk is small.
Because of the low diagnostic yield of CT scans in the diagnosis of pediatric headache, the American Academy of Neurology (AAN) published practice parameters specifically recommending against neuroimaging for children with headache and a normal history and neurologic examination.18,19 This recommendation was endorsed by the American Academy of Pediatrics (AAP) and the American College of Radiology (ACR). The ACR instituted the Choosing Wisely campaign, which includes a checklist of 5 questions physicians and patients should ask when a CT scan is recommended.20 The highlighted points advise against CT scans for uncomplicated headaches, suspected pulmonary embolism, admission or preoperative chest radiographs, suspected appendicitis in children, and follow-up imaging for inconsequential adnexal cysts, in cases with an unremarkable history and examination.
Despite the practice parameters, use of neuroimaging, and CT scans in particular, in children has changed little in recent years.21–23 Although the overall ratio of CT scans in children is lower than in adults, pediatric CT scans have increased disproportionately in older children.22 In an analysis of neuroimaging rates for pediatric nonacute headache, rates remained constant before and after publication of the 2002 AAN guidelines: in 1992, 43% of children presenting at a pediatric neurology clinic with nonacute headache underwent neuroimaging compared with 45% in 2004.21 In a more recent analysis spanning 2003 through 2010, a CT scan was performed in 5.5% of all pediatric ED visits, with head CT scans comprising 63% of the total.23
The current study originated with discussions between leadership within the AAP and WellPoint, Inc, to address the question, “to what extent do current practice patterns for treatment pediatric headache align with practice guidelines?” An advisory group including representatives from the AAP, AAN, and the American Academy of Family Physicians was convened. This study resulted from this advisory group’s initial questions. Previous analyses examined neuroimaging as a diagnostic tool for children with headache, but those studies were performed in pediatric neurology clinics,7,8,11,13,21 EDs,3,5,22,23 or an ambulatory care setting.10 This large-scale retrospective claims analysis sought to determine current, real-world practice patterns in the use of neuroimaging to diagnose pediatric headache. The comprehensiveness of the claims data enabled analysis across all treatment settings to identify factors associated with increased likelihood of neuroimaging. This study is the first that we are aware of comparing children across treatment settings and provider specialties.
Methods
Data Source
This study was a retrospective, observational cohort analysis using commercial claims data. Data were obtained from the HealthCore Integrated Research Environment, an integrated medical, pharmacy, and eligibility claims data set of commercially insured patients. The database includes claims data for 14 major commercial health plans across the United States. The health plans include a wide range of product offerings, including preferred provider organizations, health maintenance organizations, fee-for-service, and consumer-directed health plans. The database includes ∼45 million total unique lives, with eligibility dating back to 2006.
Patients
Patients included in the study were children and adolescents between the ages of 3 and 17 years on the index date. To be included in the study, patients were required to have at least 2 distinct medical claims for headache, identified by using International Classification of Diseases, Ninth Revision, Clinical Modification, diagnosis codes for headache (Supplemental Appendix A) from January 1, 2007, through December 31, 2008. The index date was defined as the date of the first headache diagnosis claim, and patients were required to have a minimum of 12 months’ health plan eligibility before and after the index date. After the initial identification period, patients were followed up until December 31, 2010, or disenrollment from the health plan. Children were excluded from the study if they had <24 months of health plan eligibility, if they had headache diagnosis claims occurring in the 12-month period before the index date, or if diagnosis codes indicating head trauma appeared during the preindex period, on the index date, or during the follow-up period (Supplemental Appendix B).
Institutional Review Board Approval
This study was a noninterventional, retrospective claims analysis. The research was conducted in compliance with state and federal laws, including the Health Insurance Portability and Accountability Act of 1996. All claims data were from a limited data set with de-identified patient information. No patients were involved in the study and thus review by an institutional review board was unnecessary.
Outcome Measures
The primary outcome of interest was utilization of CT scans of the head on or after the patient first presented with a headache in a physician’s office or in an ED setting. In addition to the binary variable of CT scan/no CT scan, we evaluated patients receiving multiple CT scans of the head and patients receiving a CT scan in conjunction with another head-related imaging procedure.
Statistical Analysis
The statistical significance of differences between patients undergoing CT scans and those who did not undergo a CT scan were assessed by using χ2 tests for categorical variables and 2-sided t tests for continuous variables. The initial variables of interest included age, gender, geographic region, length of patient follow-up, initial headache diagnosis on index date, change in headache diagnosis category after index date, provider specialty on index diagnosis, number of physician office visits since index date, days between first and last headache diagnosis, number of ED visits during the follow-up period (inclusive of index date), diagnostic procedures (eg, MRI, lumbar puncture), headache treatment (including use of abortive/rescue headache medications), use of preventive/prophylactic medications, use of nonpharmacologic treatment (eg, acupuncture), and presence of comorbid conditions. The comorbid conditions of interest were identified during the 12-month preindex period and included diagnoses for attention-deficit/hyperactivity disorder, anxiety, asthma, cerebral palsy, depression, epilepsy, pervasive developmental disorders, antisocial personality disorder, and stress (Supplemental Appendix C).
A binomial logistic regression model was used to measure the relationship between the outcome of interest (likelihood of receiving a CT scan) and the following variables: age, gender, geographic region, provider specialty on index diagnosis, number of physician office visits, ED visits, diagnostic procedures (eg, MRI, lumbar puncture), use of abortive/rescue headache medications, and presence of comorbid conditions. Statistical analyses were conducted by using SAS version 9.1 (SAS Institute, Inc, Cary, NC). An α level of .05 was set for each test.
Results
Patient Population
There were 15 836 children meeting study criteria, with 4034 (25%) undergoing ≥1 CT scan during the follow-up period (Table 1). The mean patient age was 11.8 years on the index date; 59% of the population was female. Although 4 categories of headache were initially identified for inclusion (migraine, other headache syndromes, psychologically related tension headache, and headache symptoms/unspecified), the majority of patients (75%) fell into the category of headache symptoms/unspecified, with migraine as the second most common category (22%) at their index diagnosis. In 60% of cases overall, the index headache category was the same as the final headache category. At follow-up, the headache category remained unchanged in 53.4% of children who had a CT scan, compared with 62.8% who did not have a CT scan. In cases in which there was a shift in headache category, the most common shift was from headache symptoms/unspecified to migraine. The most common comorbid condition was asthma, with the diagnosis appearing in 10% of the patients’ claims history before the index date.
Patient Characteristics
Patients had a mean follow-up time of 30 months (Table 1). On average, patients received 3 office visits during the follow-up period (inclusive of index date), most commonly receiving care from a pediatrician (43%) or family physician (24%) for the index event (Table 2). In 7% of cases, the ED was the source of treatment of the index event, and 16% of patients were treated in the ED with a diagnosis of headache at some point in the study period. In terms of diagnostic procedures other than CT scans, 23% of patients underwent MRIs at some point during the study period. Lumbar punctures, radiographs, and electroencephalograms were performed rarely, each for <5% of the patient population. Patients who underwent CT scans typically did so within a month of their index diagnosis (74% of cases); however, across the entire population, the mean length of time to CT scan was 79 days (Fig 1).
Characteristics of Interest According to CT Scan Diagnostic Procedures
Time to CT scan among pediatric headache patients. Patient without ED visit (blue); patient with ED visit (red).
Univariate Results
Children who underwent CT scans were, on average, 2 months older than children who did not have CT scans. This difference was statistically significant (P < .01) but not clinically meaningful. There was a nonsignificant difference in gender between those who had a CT scan and those who did not. Most of the comorbid conditions were not significantly different between the 2 groups. The 1 exception was anxiety, which was slightly less common among patients who underwent CT scans than those who did not (2.2% vs 2.9%, respectively; P < .01).
Patients who received CT scans had the same likelihood as those who did not receive a CT scan of being treated by a pediatrician on the index date (43% for both groups). However, children who underwent CT scans were more likely than those who did not to be treated by a family physician (30.5% vs 21.8%, respectively; P < .01). Patients who underwent CT scans were much more likely than those without CT scans to receive care in the ED, either at the index date or during the follow-up period (32.6% vs 9.7%, respectively; P < .001). Patients in both groups received the same number of office visits on average (3.0 for both groups), although patients undergoing CT scans were more likely to have received care only in the ED (4.0% vs 1.6%; P < .001). Although ED visit was highly correlated with CT use, it is important to note that two-thirds of the patients receiving CT scans had no ED visits at all during the study period. After excluding patients with ED visits, 20.3% of patients received a CT scan either on the index date or at some point in the follow-up period. Patients undergoing CT scans were less likely to undergo an MRI (15.8% vs 25.6%; P < .001).
Logistic Regression Results
Consistent with the univariate results, the strongest association in the logistic regression was with ED use: pediatric patients with headache who visited the ED were 4 times more likely to undergo a CT scan as those who did not visit the ED (odds ratio: 4.4; P < .001 [95% confidence interval (CI): 3.96–4.85]) (Table 3).
Logistic Regression Model (CT Scan Versus No CT Scan)
Age was not statistically significant in the logistic regression model, consistent with the univariate results. Female patients were somewhat less likely than male patients to undergo CT scans (odds ratio: 0.89; P < .01 [95% CI: 0.83–0.97]). The western geographic region was associated with lower rates of CT scan than the central or eastern regions (odds ratio: 0.66; P < .01). This finding is consistent with other internal analyses of regional differences in imaging rates, in which the health plans in the western region of the country tend to have lower rates (WellPoint, internal analysis, 2012 data). Geographic differences in practice patterns, although not specific to this population, have been long recognized, particularly via the work of the Dartmouth Atlas.24
It is interesting to note that provider specialty was associated with likelihood of receiving a CT scan. Receiving care from a neurologist was strongly associated with a lower likelihood of a child undergoing a CT scan (odds ratio: 0.37; P < .01 [95% CI: 0.31–0.46]), whereas receiving care from a family physician was associated with a higher likelihood of a child undergoing a CT scan (odds ratio: 1.2; P < .001 [95% CI: 1.09–1.32]).
Discussion
Practice parameters issued by the AAN and endorsed by the AAP and ACR recommend against neuroimaging as a diagnostic tool for children presenting with headache and no other signs or symptoms.18,19 Despite these recommendations and numerous studies noting the lack of effectiveness of neuroimaging in pediatric headache,1,5–13 the use of neuroimaging in children remains high. Previous cross-sectional analyses of children with nonacute headache in a pediatric neurology clinic found 45% of the children had at least 1 neuroimaging study performed.13,21 Much of the previous work examining CT use in children with headache focused on the ED setting.3,5,22,23 Consistent with this previous research, we found a high rate of CT scan use in the ED, and ED visits were highly correlated with the likelihood of a child receiving a CT scan when presenting with a headache. However, our study was unique in examining the use of CT scans for pediatric headache not only in EDs but also across all treatment settings and various physician specialties. Across this broad cross-section of settings and specialties, CT scans were still commonly used diagnostic procedures even when the patient did not visit the ED.
Symptoms that indicate the need for CT scan include age <3 years; explosive headache; associated changes in mental status or performance; awakening with headache, nausea, and vomiting; and steadily worsening pattern of headache.25 Because we used claims data rather than medical records to determine which patients had a CT scan, we were unable to assess for the presence of these symptoms. We acknowledge that this lack of data represents a significant limitation. Nevertheless, given the large percentage of patients with headache symptoms/unspecified and the fact that the majority of these patients did not receive a more specific diagnosis during the follow-up period raises concerns regarding the reliance of CT scans in the care for pediatric patients presenting with headaches. It is reasonable to suggest that when individuals have syndromes that clearly require imaging, it is more likely that the more specific and more actionable diagnosis would be used.
These findings are consistent with the literature. Among children with chronic headache who had been referred to a specialty clinic, 23% of those referred by pediatricians had already had 1 head scan before referral.2 Separate studies performed in neurology clinics and an ambulatory care centers found 76% to 80% of neuroimaging tests were ordered by primary care physicians rather than specialists.10,13,21 The widespread CT utilization across physician specialties may be due to misperceptions of the clinical benefits and risks of CT scan for diagnosis of headache or to misinterpretation by physicians of the expectations of children and their parents. Pediatricians surveyed indicated they believed the primary concern of mothers of children with headache was the presence of a tumor, and they therefore focused on diagnostic testing rather than treatment.26 Although valid reasons may exist for the differences among physician specialties in ordering diagnostic tests, large discrepancies may indicate potential overuse or inappropriate use of certain procedures and could be used as the basis for developing future guidelines or educational programs.
Physicians also may underestimate the risks associated with CT scans.22 Of particular concern is that in addition to the lack of clinical effectiveness, CT scans have been associated with an increased lifetime risk of cancer.15–17 The risk from ionizing radiation is cumulative, with younger children facing the highest risk.16 However, physicians ordering CT scans may underestimate the radiation risk or may mistakenly believe the risk is limited to infants.22 Only 9% of ED physicians in a survey perceived an increased risk of cancer associated with CT scans, compared with 47% of radiologists surveyed.27 Whereas CT scans accounted for 13% of all diagnostic radiology procedures in US hospitals, they contributed 70% of the collective radiation dose delivered to patients. Few patients reported being informed of these risks, and 78% of physicians admitted they did not explain the potential risks to patients.
This study had several limitations. The study data were obtained from a large, geographically diverse population. However, as noted earlier, this is a claims-based analysis, and the potential exists that some claims may have been miscoded. Although the sample was large and diverse, all patients were members of a US employer-based health plan, and the results may not be generalizable to patients with other types of health insurance or living outside of the United States. As noted, it was difficult to determine whether a patient had a normal neurologic examination based on claims data and therefore a CT or MRI scan that conformed to clinical guidelines. A chart review would be needed to properly make that determination. Future research may further explore the frequency as to which neuroimaging tests indicate abnormalities, and whether scans ordered by generalists, such as pediatricians or family practitioners, differ from those ordered by neurologists in terms of detected abnormalities.
Conclusions
The likelihood of children receiving a CT scan in a variety of practice settings remains high and continues to be of concern given the cumulative risks associated with ionizing radiation and associated cancer risks. Although ED use was associated with the greater likelihood of a CT scan, we also saw widespread use of CT scans for patients treated by family physicians and pediatricians. This study affirms guidelines recommending against CT scans for uncomplicated headache. Furthermore, it suggests an opportunity exists to reduce exposure of children and adolescents to ionizing radiation by ensuring that a CT scan ordered on a child with a headache is done so only when truly indicated.
Acknowledgments
The authors acknowledge Cheryl Jones for editorial assistance in preparing the manuscript, and Burak Ozbay and Brian McNeeley for assistance with data collection and analysis.
Footnotes
- Accepted April 2, 2013.
- Address correspondence to Andrea DeVries, PhD, HealthCore, Inc, 800 Delaware Ave, 5th Floor, Wilmington, DE 19801. E-mail: adevries{at}healthcore.com
Dr DeVries developed the initial study concept and design, interpreted the data, and wrote and revised the manuscript; Dr Getchius and Dr Wall contributed to the initial study concept and design, contributed to data interpretation, and reviewed the draft manuscript; Ms Li analyzed and interpreted the data, and critically reviewed and revised the manuscript; Dr Whitney contributed to the initial study concept and design, contributed to data interpretation, and reviewed and revised the draft manuscript; Dr Rosenberg developed the initial study concept, contributed to the study design and data interpretation, and reviewed the draft manuscript; and all authors approved the final submitted draft.
FINANCIAL DISCLOSURE: Dr DeVries and Ms Li are employees of HealthCore, Inc, an independent research organization that received funding from WellPoint, Inc, for the conduct of the study. Drs Whitney and Rosenberg are employees of WellPoint, Inc. The other authors have indicated they have no financial relationships relevant to this article to disclose.
FUNDING: This study was funded by WellPoint, Inc.
References
- Copyright © 2013 by the American Academy of Pediatrics
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