Do Rural and Urban Children Have Comparable Asthma Care Utilization?

DQ Rural and Urban Children Have Comparable Asthma Care Utilization?

Barbara l? Ymn, M.D., MSc., Arch G. Mainous III, Ph.D., Margaret M . Love, Ph.D., and William Hueston, M.D., M.S.

ABSTRACT This study compares asthma-related health care visits and drug therapy for rural and nonrural Kentucky children with Medicaid health insurance in 1995. The 8,634 children with asthma had a mean age of 5.7 years. Ninety-two percent made at least one asthma ofice visit, and 13 percent were hospitalized. The urban and rural patterns of care for childhood asthma wried in some potentially important y s . Urban children were twice as likely as rural children to see an asthma specialist (5 percent vs. 2.5 percent, P<0.05), 2.7 times as likely to receive asthma care in an emergency department (19 percent vs. 7 percent, P 4 0 1 ) and 1.4 times as likely to receive oral steroids (26 percent VS. 12 percent, P=0.04). I f given inhaled anti-inflammatory medication, rural children weye more likely to receive inhaled steroids while urban children were more likely to receive cromoglycates.

sthma, the most common chronic disease of childhood, affects an estimated 5 million children, or almost 7 percent of all children, in the United States (Brown, A et al., 1997; Crespo, 1998). Asthma di-

rectly resulted in almost 300 hospitalizations and two deaths per 100,000 children in 1994 (Crespo, 1998); it is the fourth leading cause of disability in children and the most common reason for missed school days (Brown, et al., 1997; Centers for Disease Control, 1992). Despite the introduction of new drugs, better understanding of asthma’s chronicity and the impor- tance of inflammation in its etiology and treatment, and the publication of national guidelines for asthma care, morbidity and mortality from asthma have not declined and may be continuing to increase (Eickholt, et al., 1997; Gerstman, et al., 1989; Harris, 1990; Killi- an, et al., 1997; National Institutes of Health, 1997; Weiss, et al., 1992).

Several recent urban-based studies suggest that much of the morbidity and most of the mortality asso-

ciated with childhood asthma could be prevented with improved care, including less dependence on emergency department care and greater use of inhaled steroids (Bielory, et al., 1996; Eickholt, et al., 1997; Legorreta, et al., 1998; McFadden, 1991). Asthma is recognized as a chronic inflammatory condition (Juniper, et al., 1990; Lemanske, et al., 1997; NIH, 1997). As recently as 1987, however, most physicians considered asthma to be synonymous with episodic bronchospasm, and therapy focused on short-acting bronchodilators usual- ly prescribed in response to an exacerbation (Habbick, et al., 1995). Recent studies continue to show a physician preference for episodic symptomatic-relief drugs compared to daily or even episodic anti-inflammatory medications (Habbick, et al., 1995).

Many studies of asthma care in U.S. children have focused on special populations, such as inner-city children (Bosco, et al., 1993; Crain, et al., 1994; Gerstman, et al., 1989; McDermott, et al., 1996) or HMO enrollees (Buchner, et al., 1997; Legorreta, et al., 1998; Stein- wachs, et al., 1995). Few studies have included large

Vol. 17, No. 1 The ]oumal of Rural Health 32

numbers of rural children (Bosco, et al., 1993) despite suggestions that the outcomes and treatment for rural children may be poor and similar to those of high-risk inner-city groups (Gerstman, et al., 1989). The lack of rural data hampers the development of rural programs to improve asthma care (D. Schmidt, National Heart, Lung and Blood Institute and National Asthma Education and Prevention Program [personal commu- nication, June 20001).

This study describes the asthma-related care for a population of rural children thought to be at high risk for adverse outcomes: poor children covered by Med- icaid. Care of the rural children is compared with asthma-related care of urban children with Medicaid insurance in the same state. Rather than rely on ex- trapolations from urban managed care studies, this study intends to inform development of targeted education and practice-modification programs that are re- sponsive to the actual practice of rural providers. - Methods

All children ages birth to 18 who were receiving Medicaid insurance in Kentucky for at least 320 days between July 1, 1994, and June 30, 1995 (the state’s def- inition of continuous enrollment), and who had one or more claims for an asthma-related diagnosis during that period were included in the cohort. Children were considered rural if their county of residence was nonmetropolitan.

The use of Medicaid data allowed investigation of a continuously enrolled population and provided a complete spectrum of ambulatory, emergency department, hospital and pharmacy information in a statewide population. Kentucky was selected for study because it has a large rural population (98 of the state’s 120 counties are nonmetropolitan), racial diversity (although more than 85 percent of the state’s population is white, non-Hispanic) and a Medicaid claims system with event-based records available for the year of interest. The state has many areas of marked poverty, with 18.4 percent of all residents under 65 receiving medical assistance for health care services. In addition, Kentucky may be more representative of less urban- ized states without large inner-city populations that may confound urban and rural comparisons.

The codes defined as asthma-related included all ICD-9 and CPT asthma codes that did not list a cardi- ac etiology (those codes are available from the author upon request). Any child having one or more asthma- related claims within the one-year period was consid-

ered to have asthma. Drug therapy claims alone were not used to identify children with asthma because many drugs (even inhaled beta-agonists) can be used for treatment of conditions other than asthma. More- over, because one purpose of the study was to evalu- ate the use of recommended medications in children with asthma, medications could not be used both to define the population and as an outcome.

Data Collection. All adjudicated claims to the Ken- tucky Medicaid program, including both Health Care Financing Administration (HCFA) 1500 and UB-92 claims filed for the study participants, were available for analysis. ICD-9-CM codes for all primary or sec- ondary diagnoses were used to classify visits according to whether they were asthma-related. CPT codes for evaluation and management were also used to identify outpatient and emergency department visits as asthma-related.

For each child defined as having asthma, demographic data including age, sex, race and county of residence were recorded. The date, site, diagnostic codes, procedure codes and provider were recorded for all asthma-related claims for each child in the asthma cohort. Claims files included visits to ambulatory care clinics, emergency departments and outpatient hospital clinics and all inpatient services.

Medicaid medication claims files (filled prescriptions) for the children in the asthma cohort were searched for all asthma-related medications. Those included short- and long-acting oral and inhaled beta- agonists, oral methylxanthines, inhaled and oral corticosteroids and cromoglycates. Leukotriene modifiers were not available to the Medicaid population at the time of the study. All available drugs in all categories were included. The date and type of each asthma-related prescription was recorded and classified as short-acting symptom (SAS) relief medications, long- acting symptom (LAS) relief medication or anti-inflammatory medications, according to the specifica- tions used by the expert panel of the National Asthma Education and Prevention Program (NIH, 1997). Anti- inflammatory drugs were further subdivided into oral steroids, inhaled steroids and cromoglycates. The total number of filled prescriptions by drug name and clas- sification were counted for each child.

Funding provided by the Office of Rural Health Policy. For more information, contact: Barbara l? Yawn, M.D., M S c , at the Department I$ Re- search, Olmsted Medical Center, 210 Ninth St. S.E., Rochester, M N 55904 or [email protected].

Yawn, Mainous, Love, and Hueston 33 Winter 2001

Data Analysis. Simple descriptive statistics were calculated for the children and compared for rural and urban groups. Rates of visits to ambulatory clinics and emergency departments (EDs) and hospitalizations were calculated. The specialty of the physician seen for each outpatient and ED visit was also recorded. It was not possible to separate hospital-based and freestanding outpatient clinic visits. For each hospitalization, the length of stay was also recorded. Rates of filled prescription medications by category were compared for rural and urban children. Subanalyses were done for children grouped into four age categories: 0- 1 year, 2-5 years, 6-11 years and 12-18 years. These groups were selected because of potential differences in the ease of recognition of asthma in children and infants, the listed age recommendations for medications such as cromolyn sodium, and the potential in- ability of young children to master h a l e r therapy. Further stratification was used to compare African American and white children in rural and metropolitan settings. Because of the small number of children in all other racial categories, analyses using race included only African American and white children.

Since asthma severity data were not available for these children, proxy measures were developed using available data. Filling 10 or more SAS prescriptions, filling any prescription for any LAS, making more than three visits to an ED for asthma care or having any asthma-related hospitalization during the year of observation was considered indicative of moderate or severe persistent asthma (NIH, 1997). The use of anti- inflammatory medications was evaluated in children meeting any of these criteria.

Results

Overall 8,634 Kentucky children receiving Medicaid during fiscal year 1995 were found to have one or more asthma-related visits and therefore considered to have asthma. Table 1 displays the demographic characteristics of the rural and urban children with asthma. Ninety-six percent (8,315) of those children were reported to be either white or African American, more than half of the children with asthma were less than 6 years old, and about 58 percent were boys. Although 59 percent of Kentucky children receiving Medicaid live in rural counties, 70 percent of the children with asthma were in rural counties. The main demographic differences between the rural and urban children were the slightly higher percentage of boys in the urban

Table 1. Demographic Description of Cohort.

Total (N= Rural Urban

8,315)* (n=5,841) (n= 2,474)

Per- centage White, 66 Black, 4 White, 19 Black, 11

Age of Total Percent Percent Percent Percent (in years) Cohort (percent) (percent) (percent) (percent)

Age (years) 0 to 1 24.5 24.6 21.7 26.7 21.7 2 to 5 30.7 31.2 27.8 30.5 29.4 6 to 11 28.0 28.1 27.8 26.7 29.5 12 to 18 16.8 16.2 22.7 16.1 19.4 Mean 5.7 f=6.0 f=7.4 fz6.1 f=6.8

sd 4.9 m=5.5 m=6.0 m=5.3 m=6.0

Sex

Male 58.7 57.6 62.6 61.5 58.5 Female 41.3 42.4 37.4 38.5 41.5

Race White 84.8 90.7 60.6 Black 15.2 6.2 34.3

* Does not include 319 children considered neither white nor black.

group and the markedly higher percentage (PC.01) of African American children in the urban group.

The children with asthma made 16,484 outpatient office visits and 1,130 emergency department visits for asthma. Rural children were more likely than urban children to have at least one office visit for their asthma (93 percent vs. 88 percent, P<O.Ol) and to have a slightly higher mean number of ambulatory visits per year (2.0 vs. 1.7, P<O.Ol). Conversely, urban children were 2.7 times as likely as rural children to be seen in the ED and were more likely to have multiple (more than three) visits to the ED (5 percent vs. 1 percent, P<O.Ol).

A total of 1,144 children (13 percent) in the full cohort had one or more asthma-related hospitalizations during the 12 months of observation. Overall a higher percentage of the rural children than urban children had one or more hospitalizations (13.6 percent vs. 12.4 percent, P=0.04). Those rates were skewed by the urban-rural differences in hospitalization of infants (20.7 percent of rural infants vs. 15.2 percent of urban infants). In all other age groups, urban children had

7'ht? \oumal of Rural Health 34 Vol. 17, No. 1

higher rates of hospitalization than rural children. Children who were hospitalized had an average of 1.7 hospitalizations during the year, with no urban-rural differences. Spirometry and pulmonary function test- ing are reported to be important for the diagnosis and management of asthma in older children (NIH, 1997). The tests were not commonly documented in those children, but they did occur more frequently in rural than in urban children (12.7 percent vs. 8.5 percent, RO.01).

The children received asthma-related prescriptions from 1,608 physicians, 708 in the rural area and 900 in the urban area. Both urban and rural children were most likely to see a primary care physician. However, the specialty of the generalist seeing the children did vary by region. In rural areas, more than 55 percent of prescriptions were written by family or general practice physicians and 18 percent were written by pediatricians. In urban areas, pediatricians wrote 31 percent of the prescriptions and family or general practice physicians 25 percent. Internal medicine physicians wrote an additional 10 percent of the asthma-related prescriptions in both urban and rural areas. Prescrip- tions from allergists and pulmonary specialists oc- curred in fewer than 6 percent of all patients and were more than twice as common in the urban than the rural areas (5.8 percent vs. 2.5 percent, P=0.05).

Drug Utilization Data. The children filled 40,210 prescriptions for asthma-related drugs, an average of 4.7 (median 4.1) prescriptions per child per year. Most (63 percent) were for inhaled and ingested beta-agonists, followed by cromoglycates (13 percent), inhaled steroids (10 percent), methylxanthines (9 percent) and oral steroids (5 percent).

Most children (82 percent) filled at least one SAS prescription during the year. Percentages were similar for urban and rural children (82.5 percent vs. 82.0 percent, respectively). African American children (both rural and urban) were more likely than white children to fill any SAS prescription (89 percent vs. 78 percent, P=0.04). Those using SAS medications filled an average of four prescriptions per year (median 3.2 and range 1 to 12).

All non-SAS categories of asthma medications were used significantly less frequently and by fewer children. Long-acting symptom relievers, primarily methylxanthines, were filled by 10 percent to 25 percent of children varying by age, race and urban or rural residence (Figure 1). Overall, those using methylxanthines filled an average of 2.3 prescriptions per year. Rural children were more likely to fill prescriptions for

methylxanthines than were urban children (16.4 percent vs. 11.4 percent, P<O.Ol), and use increased with age, becoming highest in all groups during the teen years (Figure 1). Inhaled salmeterol use was uncom- mon, with most use occurring in the oldest age group (4.1 percent in 6- to 11-year-olds and 7.9 percent in 12- to 18-year-olds). No significant differences were found in use of salmeterol between urban and rural children.

Anti-inflammatory prescriptions were more commonly filled than prescriptions for LAS medication but less commonly than prescriptions for SAS medications. Although the overall percentage of children filling any anti-inflammatory drug prescription was similar in rural and urban children, some differences in the type of drug used were apparent. Rural children were more likely than urban children to use an inhaled steroid (18.3 percent vs. 11.5 percent, P<O.Ol). Conversely, urban children were more likely than rural children to fill a prescription for cromoglycates (29 percent vs. 19 percent, RO.01) . Inhaled steroid use increased with increasing age of the child (5 percent in 2- to 5-year-olds and 31 percent in 12- to 18-year- olds, RO.01) while the use of cromoglycates decreased (26 percent in 2- to 5-year-olds and 14 percent in 12- to 18-year-olds, RO.01). The overall result is a decrease in use of any anti-inflammatory drug in the oldest children, falling from 40 percent of preteens to fewer than 30 percent of teens. Fewer than 5 percent of children in any age group filled 10 or more prescriptions for anti-inflammatory drugs, suggesting that daily use was very limited in both rural and urban children. Inhaled anti-inflammatory drugs (cromolyn sodium and inhaled steroids) were prescribed 0.25 times as often as SAS drugs and in 0.33 times as many children. The ratios of anti-inflammatory drug use were higher for rural children than urban children and for white children than African American children.

The percentage of urban children filling one or more prescriptions for oral steroids was significantly higher than for rural children (16.2 percent vs. 11.8 percent, P=O.Ol). In both urban and rural children, the use of oral steroids increased with the age of the child and was more common in African American than in white children. Oral steroid use was uncom- mon before age 6, with fewer than 5 percent filling a prescription and on average filling only one prescription per year. After age 6, however, more than 20 percent of children (more urban than rural children) filled an average of two oral steroid prescriptions during the year.

Yawn, Maimis, Love, and Hueston . 35 Winter 2001

Figure 1. Use of Methylxanthines by Age, Race and Rural-Urban Status.

0 Age 2-5 Age 6-1 1

OAge 12-18

The type of medication prescribed varied by specialty of the physician seen. Allergists and pulmonologists were the physician group most likely to prescribe cromoglycates (45 percent of patients using cromoglycates) followed by pediatricians (26 percent), with family physicians much less likely to use cromoglycates (10 percent) (P<O.Ol). Subspecialists were also more likely to prescribe steroids (39 percent) than were family physicians (29 percent) and pediatricians (22 percent) (P=O.Ol). Methylxanthines were most commonly used by family physicians (18 percent) and allergists (1 6 percent) compared to pediatricians (12 percent) (P=0.04).

ed to disease severity. Although it was not possible with the available data to assess asthma severity di-

The differences in prescribing are likely to be relat-

rectly, it was possible to compare drug use with events that may serve as a proxy for severity. Table 2 displays the patterns of drug use in rural and urban children stratified by proxy measures for severity. Hospitalized children were about twice as likely as those not hospitalized to use an inhaled anti- inflammatory drug. Oral steroids were a more likely response to hospitalization in urban children than in rural children. An almost identical urban-rural difference in use of oral and inhaled anti-inflammatory is seen for the group of children with frequent ED visits. Regular use of an SAS (more than 10 prescriptions per year) was more likely to be accompa- nied by at least one prescription for an inhaled anti- inflammatory in rural children than in urban children.

"he ]0umal of Rural Health 36 Vol. 17, No. 1

Table 2. Percentage of Urban and Rural Children by Sentinel Event Receiving Drug Therapy.

Rural (Urban)

Oral Inhaled Cromo- LAS Steroids Steroids glycates

~ ~~~~

One or two hospitalizations 27 (21) 20 (35) 29 (21) 38 (60) Three or more ED visits 35 (47) 47 (77) 24 (40) 41 (53) Ten or more SAS prescriptions 43 (41) 37 (39) 51 (37) 61 (63) Any oral steroid 32 (29) NA 44 (35) 31 (43) Any LAS NA 23 (41) 35 (39) 24 (47)

Note: LAS = long-acting symptom, ED = emergency department, SAS = short-acting symptom, NA = not applicable.

Discussion

In this cohort of Kentucky children with Medicaid insurance, asthma care of rural children differed from the care of urban children in four areas. Rural children with asthma were more likely than urban children with asthma to be given inhaled steroids, less likely to use oral steroids, less likely to visit an ED, and after infancy were less likely to be hospitalized. Our data do not substantiate an adverse difference in the care of rural children with asthma. However, our data do suggest that both urban and rural children continue to have their asthma treated as an episodic rather than chronic condition.

Each of the differences noted deserves further con- sideration. Two potential factors could have contribut- ed to the differences observed in the use of emergency departments and oral steroids. First, African American children have been reported to have more severe asthma than white children (Brown, et al., 1997). As a percentage of the sample, our urban cohort contained nearly three times as many African American children as the rural cohort. That could translate into a higher severity of illness in the urban group, leading to greater ED use and more frequent use of oral steroids. Conversely, more frequent use of the term asthma as opposed to wheezing or reactive airway disease in children with mild disease could lower ED use in the rural group.

Another possible explanation of higher ED and oral

steroid use in urban children might be more restricted access to care for urban poor children. The lack of a usual source of care is supported by our data, which showed that a higher percentage of urban children had no documented clinic or ambulatory care visit for asthma (12 percent vs. 7 percent). Children without a usual source of care might delay care until later in the course of an asthma exacerbation, leading to an emergency visit and use of oral steroids. This hypothesis fits with other studies, which have shown decreased use of emergency department visits and oral steroids in children assigned a usual source of medical care (Bielory, et al., 1996; Gottlieb, et al., 1995; Naish, et al., 1995).

The significantly higher use of hospitalization found here for rural infants may reflect the services available in rural emergency departments rather than asthma recognition or severity. Many urban emergency departments offer full-time emergency physician staff and observation rooms that provide two to 24 hours of observation for a child having an asthma exacerbation (Tagonski, et al., 1995). Rural hospitals are unlike- ly to have this type of ED staff or care available, so rural children may require admission more often than urban children who can be observed and treated for an extended period in the ED. The differences in services provided in the ED are difficult to track using the claims data set, and therefore differences in emergency department services and practices cannot be confirmed from this study. It is also possible that urban infants hospitalized with respiratory problems are more likely than rural infants to receive some label other than asthma. That might lower the apparent rate of hospitalizations for asthma in the urban infants. Overall both the urban and rural rates of hospitalization are higher in this Kentucky Medicaid population than hospitalization rates reported in many studies of childhood asthma care (Steinwachs, et al., 1995; Tagon- ski, et al., 1995).

The most distressing observation of this study may be the appearance that asthma continues to be managed as an acute illness. In this group of Medicaid-insured children, the overall ratio of beta-agonists to inhaled anti-inflammatory (SAS/anti-inflammatory, 2.9 to 1) medications is better than the target of at least 3 to 1 set by some national experts and higher than ratios published in other reports of asthma management (Gorton, et al., 1995; Naish, et al., 1995). Although this is encouraging, Kentucky children with major sentinel events such as hospitalization, who should all be can- didates for inhaled anti-inflammatory medications, were given anti-inflammatory medication only 40 per-

Y a w , Mainous, Lnve, and Hueston 37 Winter 2001

cent to 60 percent of the time. In fact, hospitalized urban children were less likely to receive inhaled steroids than children with any other sentinel event. The difference cannot be explained by age, as hospitalized children tended to be older in the urban cohort. In addition, the number of children with enough filled prescriptions to accommodate daily use of any type of medications was small.

Two other drug use patterns are worthy of note. First, the use of methylxanthines by children of all age groups, with increased use in the older age groups, is interesting. Methylxanthine is not the drug of choice for control of either the inflammation or the symp- toms of asthma (NIH, 1997). The use of methylxanthine cannot be explained by formulary restrictions in Kentucky nor by a single physician specialty. Al- though use was more common among family physicians and allergists, pediatricians also prescribed methylxanthines in all age groups of children. Contin- ued use of methylxanthines might reflect reluctance to change from earlier prescribing patterns or the success experienced with its use previously (Campbell, et al., 1995; Jenne, 1990; Kemp, 1993; Lang, et al., 1997; Phin, et al., 1993; ROSS, 1995; Warner, 1995). The second pat- tern of interest is the use of different types of anti-inflammatory drugs in urban and rural children-pre- dominant use of cromoglycates in urban children and inhaled steroids in rural children. The difference was clearly related to the specialty of the physician prescribing. Compared with family physicians, allergists were 4.5 times as likely and pediatricians 2.5 times as likely to use cromoglycates. The differences might reflect different levels of concern about growth retarda- tion and steroid use (Allen, et al., 1994; Balfour-Lynn, 1986) or less comfort, familiarity or success with cromoglycates among rural family physicians (Creti- cos, et al., 1995). Recent studies suggesting greater ef- ficacy of inhaled steroids over cromoglycates in pre- venting alveolar basement membrane changes (Olivi- eri, et al., 1997) make this difference worthy of further exploration.

The overall low rate of anti-inflammatory medication use in childhood asthma patients observed in this study is not unique to our population. In a 1995 study looking at poor children seen in the ED of the Arkan- sas Medical Center, 23.5 percent of children reported filling one or more prescriptions for an inhaled steroid and 8 percent filled one or more prescriptions for oral steroids annually. Although the percentage of children with an ED visit who filled at least one anti-inflammatory prescription was similar in the Arkansas and Kentucky cohorts, Kentucky children with ED visits

were almost 10 times as likely to fill a prescription for oral steroids as the Arkansas children. In another study of pharmacy claims data from five managed care organizations, 30 percent of children filled one or more inhaled anti-inflammatory prescriptions each year, with use increasing from only 12 percent in the first year of life to 36 percent in the grade school age group. Similar results were obtained in a population- based study of privately insured middle-class children in Rochester, Minn., where about 28 percent of children received an inhaled anti-inflammatory medication (Eickholt, et al., 1997). Only one study, using data from 16 large staff-model managed care organizations (MCOs) (Steinwachs, et al., submitted), has shown widespread use of inhaled anti-inflammatory medications for asthma. In that study, 67 percent of all the MCO patients reported that they had filled at least one prescription for a corticosteroid inhaler in the pre- vious year.

Our ability to draw conclusions is limited by the availability of only administrative or claims data. It is therefore impossible to assess the adequacy of therapy based on the severity of the asthma or to know what other drugs or types of care may have been suggested or prescribed by the physician but not implemented by the patient or their family (Celano, et al., 1998; Chapman, et al., 2000; Cochrane, et al., 2000). Howev- er, the ability to use sentinel events and complete drug listings of prescriptions filled is valuable. The au- thors did not attempt to determine whether drugs such as the anti-inflammatory medications were prescribed before or after sentinel events.

In summary, the care of asthma in Kentucky children does not appear to be adversely affected by rural residence compared with living in a metropolitan area. In fact, whether because of lack of primary care access or greater severity of disease, urban children were more likely to receive asthma care from an emergency department and after age 1 to be hospitalized for their asthma. As observed in other settings, the long-term use of anti-inflammatory medications fell below recommended levels for both urban and rural children.

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Do Rural and Urban Children Have Comparable Asthma Care Utilization?