Hospitalizations For Ambulatory Care Sensitive Conditions Research Articles

Hospitalizations for Ambulatory Care–Sensitive Conditions: Where Do We Go From Here?

In this issue of Ambulatory Pediatrics, Agha and colleagues demonstrate that lower socioeconomic status, measured by neighborhood income, is associated with higher hospitalization rates for ambulatory care–sensitive conditions (ACSC) among children born in Toronto between 1993 and 2001. Their findings are consistent with prior research that has used census information, hospital discharge files, indices of clinician supply, and insurance claims to demonstrate a relationship between social disadvantage or limited access to health care and higher rates of ACSC hospitalization in children. Many researchers have assessed the association between social factors, delivery system characteristics, and ACSC hospitalizations over the last 10 years because the hypothesis that timely ambulatory care can prevent unnecessary hospitalizations has an intuitive appeal, and because rates of ACSC hospitalization can be easily measured from claims data. However, this research has proceeded without a critical assessment of 3 underlying assumptions about the meaning and use of ACSC: (1) that ACSC hospitalizations can in fact be prevented by timely ambulatory care; (2) that the forces associated with ACSC hospitalizations are distinct from those that affect hospitalizations for other reasons; and (3) that interventions at the level of the child, the clinic, or the delivery system as a whole can reduce the incidence of ACSC hospitalizations. Existing research does not conclusively support any of these assumptions. First, the term ambulatory care–sensitive conditions may be a misnomer. The commonly used list of ACSC in children includes acute illnesses such as pneumonia and gastrointestinal illnesses as well as chronic conditions such as asthma and seizure disorders. This list of ACSC was based on expert consensus about conditions for which early treatment might prevent hospitalizations, but little evidence supports this belief. Although some studies have found that children with ACSC hospitalizations have lower previous use of ambulatory care than children not hospitalized for these conditions, others have found similar or higher rates of ambulatory care for children later

The Role of Rural Health Clinics in Hospitalization due to Ambulatory Care Sensitive Conditions: A Study in Nebraska

Hospitalization due to ambulatory care sensitive conditions (ACSCs) is often used as an indicator for measuring access to primary care. Rural health clinics (RHCs) provide basic primary care services for rural residents in health professional shortage areas (HPSAs). The relationship between RHCs and ACSCs is unclear. The purpose of this study was to examine the relationship between the presence of RHCs in rural HPSAs and the likelihood of having an acute or chronic ACSC as the reason for hospitalization. Nebraska hospital discharge data (1999-2001) and the 2003 Area Resource File were used in this analysis. A multilevel logistic regression analysis was used to examine the relationship between the presence of RHCs in rural HPSAs and the likelihood of having an ACSC as the reason for hospitalization, after controlling for individual characteristics and county-level contextual factors stratified by 3 age groups. The eligibility for logistic regression was limited to patients from 28 rural Nebraska counties designated as HPSAs in 2001. Patients with commercial payers were excluded from the study. Elderly patients residing in rural Nebraska HPSAs with at least one RHC were significantly less likely to have a hospitalization due to chronic ACSCs. The presence of RHC is a significant factor associated with fewer hospitalizations for chronic ACSCs among the rural elderly residing in HPSAs.

Recent trends in pediatric hospitalization in New York state

To describe changing rates of disorders associated with child hospitalization. Trends for the 100 diagnosis related groups (DRGs) with the largest number of hospitalizations (0-14 years) were analyzed. Children were hospitalized at an average annual rate of 35 per 1000 age-specific population during 1996 to 2002. The hospitalization rate decreased by 2.3% per year. The top 100 DRGs accounted for 90% of all 949,376 child hospitalizations. Hospitalization for mental illness increased by 5.5% per year, accounting for more than 4% of all child hospitalizations in 2002. Ambulatory care-sensitive medical conditions (asthma, gastrointestinal disorders, pneumonia, seizures) continue to be leading causes of hospitalization, and they are declining no faster than the overall rate. DRGs with a significantly faster rate of decline than the overall trend included surgical procedures for which inpatient care is often unnecessary (-12.3%/year, accounting for 11% of the overall decline) trauma-related diagnoses (-4.4%/year, accounting for 7% of the overall decline), and HIV-related conditions (-31.7%/year, accounting for 3% of the overall decline). The rising rate of hospitalization associated with child mental illness may represent a clinically important trend. Rates of hospitalization for ambulatory care-sensitive conditions have not declined substantially despite the availability of evidence-based strategies to avoid serious illness.

The Effect of Medicare Health Maintenance Organizations on Hospitalization Rates for Ambulatory Care-Sensitive Conditions

The objective of this study was to estimate the effect of Medicare Health Maintenance Organization (HMO) enrollment on hospitalization rates and total inpatient days for ambulatory care-sensitive conditions (ACSCs) after controlling for selection. Simultaneous equations using a discrete factor selection model are used to estimate the probability of HMO enrollment, hospitalization rates, and total inpatient days for ACSCs. Enrollment data on Medicare beneficiaries in California were linked to hospital discharge data from the California Office of Statewide Health Planning and Development for January through December 1996. The following beneficiaries were excluded: 1) end-stage renal disease, 2) under 65 years of age, 3) not covered by both Medicare Part A and Part B, 4) switched between HMOs and fee-for-service (FFS), and 5) switched between HMOs. The sample was stratified by age, gender, race, county, disability, Medicaid eligibility, HMO status, and death. A 2% random sample from the 4 California counties with the largest Medicare enrollment yielded 10,448 HMO enrollees and 11,803 FFS beneficiaries. Using a discrete factor selection model, we estimated the rate of ACSC hospitalizations among FFS beneficiaries would decline from 51.2 to 44.2 per 1000 if all FFS beneficiaries joined an HMO. Similarly, the mean total inpatient days for ACSC hospitalizations would be reduced from 7.5 days to 5.1 days if all FFS beneficiaries joined an HMO. After controlling for selection, Medicare HMO enrollees have lower hospitalization rates and fewer total inpatient days for 15 ACSCs than Medicare FFS beneficiaries. These findings suggest selection of healthier beneficiaries into HMOs does not completely explain their lower rates of ACSC hospitalization.

Accuracy of Medicaid Payer Coding in Hospital Patient Discharge Data

Ambulatory care-sensitive hospitalization rates derived from hospital discharge data have been used to compare ambulatory care across insurance and delivery system groups. We sought to quantify the impact of coding inaccuracies in hospital discharge data on counts of hospitalizations for ambulatory care-sensitive conditions among Medicaid beneficiaries. This was a cross-sectional comparison of administrative databases of all California Medicaid beneficiaries younger than 65 years of age. We compared the number of hospitalizations that were attributed to Medicaid beneficiaries in California's hospital discharge data for 1994 to 1999 with the number derived from a file that linked hospital discharge data with the Medicaid eligibility file. Hospital discharge data undercounted 28.2% of hospitalizations for ambulatory care-sensitive conditions among Medicaid beneficiaries and overcounted 13.4% of such admissions among non-Medicaid beneficiaries. Approximately 5% of hospitalizations for ambulatory care-sensitive conditions captured as Medicaid admissions in routine hospital discharge data were among patients who gained Medicaid coverage as a result of the hospitalization. Patients who acquire Medicaid coverage as a result of a hospitalization are much more likely to be placed into Medicaid fee for service rather than Medicaid managed care which biases comparisons of these 2 delivery models. Caution should be used in the interpretation of Medicaid hospitalization rates as calculated from routine hospital discharge data. State agencies that provide hospital discharge data should consider the opportunity to improve the evaluation of Medicaid services by linking hospital discharge data with Medicaid enrollment files.

The relationship between a dementia diagnosis, chronic illness, medicare expenditures, and hospital use.

To determine whether dementia increases medical expenditures, the probability of hospitalization, and potentially preventable hospitalization, controlling for variables including age and comorbidity. Cross-sectional analysis of 1 year of claims data comparing usage by patients with claims for dementia with usage by those without dementia. A nationally representative 5% random sample of Medicare beneficiaries in 1999. Medicare beneficiaries aged 65 and older with fee-for-service Medicare Parts A and B coverage for 1999 (N=1,238,895; dementia patients n=103,512). Per capita expenditures, rate of all-cause hospitalization, rate of preventable hospitalization as defined using ambulatory-care sensitive condition (ACSC) admissions, and dementia identified using International Classification of Diseases, 9th Edition, codes 290, 294, and 331. Prevalence of dementia was 8.3%. In a model of expenditures in those who survived the year adjusting for age, sex, race, and comorbidity, dementia was associated with an incremental cost of 6,927 US dollars, or 3.3 times greater total expenditures than in nondementia patients (P<.001), with higher expenditures for each specific type of Medicare service. Hospitalization accounted for 54% of adjusted costs. The adjusted odds of hospitalization associated with dementia were 3.68 (95% confidence interval (CI)=3.62-3.73) and adjusted odds of ACSC hospitalization were 2.40 (95% CI=2.35-2.46). In those who died, the associations were positive but of smaller magnitude. In a nationally representative sample, higher Medicare expenditures associated with a diagnosis of dementia are in large part due to increased hospitalization. Further study is needed into the factors associated with high rates of hospitalization in dementia patients including aspects of ambulatory management that may be improved.

Morbidity Experiences and Disability Among Canadian Women.

Health IssueWomen are more frequently affected by chronic conditions and disability than men. Although some of these sex differences have been in part attributed to biological susceptibility, social determinants of health and other factors, these gaps have not been fully explained in the current literature. This chapter presents comparisons of hospitalization rates, and the prevalence of chronic conditions and physical disability between Canadian women and men and between various subgroups of women, adjusting for selected risk factors. The Canadian Hospital Morbidity Database (2000–2001) and Canadian Community Health Survey (2000–2001) were used to examine inpatient hospital morbidity, prevalence of chronic conditions and disability.Key FindingsHospitalization rates were 20% higher among women than men. This was due to the large number of hospitalizations for pregnancies and childbirth. When "normal" deliveries were excluded, hospitalization rates remained higher among women. Women had slightly lower rates of hospitalizations for ambulatory-care sensitive conditions than men. Prevalence of activity limitation (mild and severe) was higher among women than men, and differences remained after adjusting for age, chronic conditions, socio-economic status, and smoking. Women who reported a disability were less likely than men to be in a partnered relationship, have less tangible social support, and have lower income and employment rates.Data Gaps and RecommendationsThe impact of morbidity and disability on Canadian women is substantial. These results identify areas for interventions among more vulnerable subgroups, and point to the need for further research in the area of risk factors for the prevention of morbidity and disability in the population.

Primary-Care Visits and Hospitalizations for Ambulatory-Care–Sensitive Conditions in an Inner-City Health Care System

Hospitalizations for ambulatory-care-sensitive conditions (ACSCs) are a marker for access barriers for children and a possible outcome measure for primary-care interventions. We assessed the relationship between primary-care utilization and subsequent ACSC hospitalization among inner-city children. We conducted a nested, case-control study of children born in 1993 in Denver Health (DH), a "safety-net" delivery system in Denver, Colo. Utilization of preventive care and other primary-care services was compared between children hospitalized for ACSCs and nonhospitalized children, who were matched by age and duration of care. Comparisons were adjusted for demographics, payer, and chronic health conditions. Of 2531 children, 115 (4.5%) were hospitalized for ACSCs. Sixty-eight percent were Hispanic, and 78% were enrolled in Medicaid. Children with ACSC hospitalization and nonhospitalized children made a similar number of preventive-care visits (2.7 +/- 2.0 vs 3.0 +/- 2.1 visits, P =.30) and other primary-care visits (4.4 +/- 4.6 vs 3.6 +/- 4.6, P =.16) between birth and hospitalization (for cases) or the same time period (for controls). After multivariate adjustment, each additional preventive-care visit (odds ratio = 0.87; 95% confidence interval: 0.67-1.12) was associated with a nonsignificant reduction in the risk of hospitalization for ACSC. Because ACSC hospitalizations are uncommon and the association between primary care and subsequent hospitalization is weak, a reduction in ACSC hospitalizations may not be a feasible outcome measure for interventions to increase the rate of preventive- or primary-care visits for underserved children within individual delivery systems.

Keeping Children Out of Hospitals: Parents’ and Physicians’ Perspectives on How Pediatric Hospitalizations for Ambulatory Care-Sensitive Conditions Can Be Avoided

Avoidable hospitalization conditions (AHCs) are hospitalizations that potentially can be avoided with timely, appropriate outpatient care. The specific reasons for avoidability, and parents and physicians' perspectives on the proportion of actually avoidable pediatric AHCs, have not been examined adequately. To identify how pediatric hospitalizations might be avoided, and to determine the proportion of avoidable AHCs according to parents and physicians of hospitalized children. Cross-sectional survey of parents, primary care physicians (PCPs), and inpatient attending physicians (IAPs) of a consecutive series of children who were admitted with AHCs to an urban hospital in a 14-month period. The 554 hospitalized children had a median age of 4 years; most were poor (median annual family income: 12,000 dollars), nonwhite (91%), and had public (73%) or no (16%) health insurance. The most frequent AHC diagnoses were asthma (43%), dehydration/gastroenteritis (16%), pneumonia (11%), seizure disorder (8%), and skin infections (8%). Only 25% of parents said that their child's admission was avoidable, compared with 29% of PCPs and 32% of IAPs. The proportion of AHC hospitalizations assessed as avoidable varied according to the source or combination of sources, from 13% for agreement among all 3 sources to 46% as identified by any 1 of the 3 sources. PCPs (71%) and IAPs (48%) significantly more often than parents (35%) cited parent/patient-related reasons for how hospitalizations could have been avoided, including adhering to and refilling medications, better outpatient follow-up, and avoiding known disease triggers. Parents (48%) significantly more often than PCPs (18%) and IAPs (37%) cited physician-related reasons for how hospitalizations could have been avoided, including better education by physicians about the child's condition, and better quality of care. Multivariate analyses revealed that an age >or=11 years, an asthma diagnosis, working poor family income, and having no health insurance were associated with approximately double to triple the odds of an avoidable hospitalization. The proportion of AHCs assessed as avoidable varies from 13% to 46%, depending on the source. Adolescents, children with asthma, children from working-poor families, and uninsured children are at greatest risk for avoidable hospitalizations. Many pediatric hospitalizations might be avoided if parents and children were better educated about the child's condition, medications, the need for follow-up care, and the importance of avoiding known disease triggers. Direct assessment by parents and physicians of hospitalized children can be an informative way to examine the proportion of avoidable pediatric hospitalizations and how they can be prevented.

Hospitalization for Ambulatory Care-Sensitive Conditions: A Method for Comparative Access and Quality Studies Using Routinely Collected Statistics

Appropriate and timely provision of ambulatory care is an important factor in maintaining population health and in avoiding unneccessary hospital use. This article describes conditions for which hospitalization rates have a strong and inverse relationship to access to high-quality ambulatory care.Three panels of Canadian physicians following different consensus techniques selected conditions for which the relative risk of hospitalization is inversely related to ambulatory care access.All panels identified asthma, angina pectoris, congestive heart failure, otitis media, gastric ulcer, pelvic inflammatory disease, malignant hypertension, and immunization-preventable infections as ambulatory care-sensitive admissions. These conditions strongly overlap with lists developed for similar purposes in the U.S. and England.Ambulatory care-sensitive conditions represent an intermediate health outcome. They are distinct from inappropriate hospitalizations. They may be useful for measuring the impact of health care policy, and for performance measurement or audit.

Hospitalization rates as indicators of access to primary care

Variations in hospitalization rates for selected conditions are being used as indicators of the effectiveness of primary care in small areas. Are these rates actually sensitive to problems in local primary care systems? This study examines the relationship between ambulatory care sensitive condition (ACSC) hospital admission rates and primary care resources and the economic conditions in primary care market areas in North Carolina in 1994. The data show a high degree of correlation between the rates and income but not primary care resources. The distribution of rates did agree with expert assessments of the location of places with poor access to health services. The data confirm that access to effective primary care reflected in lower rates of ACSC admissions is a function of more than the professional resources available in a market area. The solution to reducing disparities in health status may not lie within the health system.

Individual sociodemographic characteristics associated with hospitalization for pediatric ambulatory care sensitive conditions.

This study examined the association of individual sociodemographic characteristics with pediatric ambulatory care sensitive condition (ACSC) hospitalizations in American hospitals while controlling for selected hospital characteristics. Data came from the 1994 National Hospital Discharge Survey. Bivariate statistical comparisons were performed to test the differences between ACSC and non-ACSC hospitalization rates in patient demographic and hospital characteristics. Logistic regression was followed to examine the relative significance of patient and hospital characteristics associated with pediatric ACSC hospitalizations. Such individual sociodemographic characteristics as age, race, and insurance status were significant predictors of ACSC hospitalization. Younger children were more likely to have ACSC hospitalization than older ones. Black children were 1.653 times more likely than white children to be hospitalized for ACSC (confidence interval = 1.53-1.79). Those with Medicaid or no secondary insurance were more likely to be hospitalized for ACSC than those with private insurance or with secondary insurance.

Variation in Hospital Discharges for Ambulatory Care-Sensitive Conditions Among Children

Ambulatory Care-Sensitive Conditions (ACSCs), conditions for which ambulatory care may reduce, though not eliminate, the need for hospital admission, have been used as an index of adequate primary care. However, few studies of ACSC have focused on children. We estimated national hospitalization rates for ACSC among children and examined the behavior of the index between subgroups of children. We used data from the 1990-1995 National Hospital Discharge Surveys (NHDS), the US census, and the National Health Interview Survey (NHIS) to calculate hospital discharge rates. Rates were estimated as the number of condition-specific hospital discharges from the NHDS divided by the population at risk, as estimated from the US census and NHIS. Predictably, ACSC hospitalization rates were significantly higher among children who were younger, black, had Medicaid insurance, and lived in poorer areas compared with their counterparts. However, the relationship between ACSCs and income and the distributions of conditions within the index varied significantly between children. ACSCs may indicate disparities in access and utilization of health care, however, the differing behavior of the index between subgroups suggests that inferences from examining rates of ACSCs may not be comparable for all children.ambulatory care-sensitive conditions, hospitalization rates.

Patient and Hospital Factors Associated With Hospital Admissions for Ambulatory Care Sensitive Conditions

Background. Patients admitted into hospitals with ambulatory care sensitive (ACS) conditions generally lack adequate primary care or are not adequately managed on an ambulatory basis. This study explored the magnitude of discharges of patients with ACS condition in American hospitals and examined patient and hospital factors associated with hospital admissions for ACS conditions. Methods. Data for this study was obtained from the 1994 National Hospital Discharge Survey. Bivariate statistical comparisons were performed to test the differences between ACS condition and non-ACS condition groups in specific demographics and hospital characteristics. Logistic regression was then applied to determine the independent effect of individual demographic and hospital factors in relation to hospitalizations for ACS conditions. Results. We found that about 12% of the hospitalized patients were discharged with ACS conditions. Hospitals likely to have a higher rate of ACS discharges were governmental, relatively small in terms of beds, and situated in the non-West region. Patients likely to be discharged with ACS conditions were older, male, African American, unmarried, without insurance, or without an expected secondary source of payment. Conclusions. Using regularly collected hospital discharge data at the national, state, and community levels, providers and decision makers can easily make timely assessments about population needs and the extent of access barriers faced by special population groups.

Pediatric hospitalization due to ambulatory care-sensitive conditions in Valencia (Spain).

Studies in the United States have demonstrated that rates of hospitalization for conditions sensitive to primary care are related to socioeconomic factors. Our objective was to identify those sociodemographic and primary care factors associated with pediatric hospitalization for ambulatory care-sensitive conditions, in a country (Spain) with a health system that provides universal coverage. Cross-sectional survey of 504 children hospitalized in a District General Hospital in Valencia, Spain. Data were gathered on sociodemographic variables, type of physician providing primary care and ambulatory care use prior to hospitalization. Analysis consisted of bivariate statistical tests and logistic regression techniques. Children who were under 2 years old and female were at significantly higher risk for hospitalization due to ambulatory care-sensitive conditions. Socioeconomic variables, type of physician or a previous visit to primary care services were not associated with a different risk of hospitalization due to these conditions. Characteristics unrelated to difficulties in access, or to type of provider, influence the risk of hospital admissions for conditions that could be prevented or managed without hospitalization. More specific classification of conditions potentially could be useful for determining which factors of structure or process of health services are related to hospitalization.