Costs to Medicaid of advancing immunosuppression in an urban HIV-infected patient population in Maryland

HIV Patients in the HCUP Database: A Study of Hospital Utilization and Costs

This study examines the utilization of hospital care by HIV patients in all hospitals in eight states (California, Colorado, Florida, Kansas, New Jersey, New York, Pennsylvania, and South Carolina), and examines the cost of hospital care for HIV patients in six of these states (California, Colorado, Kansas, New Jersey, New York, and South Carolina). The eight states in the sample account for more than 52% of all persons living with AIDS in the United States; the six states account for 39%. The unit of observation in both studies is a hospital admission by a patient with HIV. Hospital data were obtained from the Healthcare Cost and Utilization Project (HCUP), State Inpatient Database (SID), which is maintained by the Agency for Healthcare Research and Quality (AHRQ). The HCUP contains hospital discharge data and is a federal/state/industry partnership to build a multistate health care data system. Using multivariate analytic techniques and data from 2000, results indicate that cost and length of a hospital stay vary significantly across states after accounting for a patient's gender, insurance type, race, age, and number of diagnoses, as well as the teaching status and ownership category of the hospital.

Do reduced inpatient costs associated with highly active antiretroviral therapy (HAART) balance the overall cost for HIV treatment?

In this article we analyse how the costs of treating patients with HIV infection in the US have changed over time, with an emphasis on the relationship between inpatient hospitalization costs and the costs of highly active antiretroviral therapy (HAART). We examine how HIV treatment modes have evolved by comparing the pre-HAART treatment period before 1996-7 with the subsequent use of HAART. We describe the sources of data on HIV healthcare service utilization, the costs of those services, and the differences between the annual costs of treating all patients with different stages of HIV and the lifetime costs of treating a person with HIV from the time of infection. The major question in estimating HIV treatment costs and their components is how to incorporate a complete set of services utilized from all providers of HIV treatment for a representative sample of patients with HIV. The literature reviewed varies significantly on both of these factors. Although the hospitalization of patients with HIV has been declining over the past 2 decades, this rate of decrease accelerated after the introduction of HAART. Initially, the declines in hospitalization and its associated costs were greater than the increases in drug therapy costs, so the annual total costs of treating patients with HIV decreased. However, subsequent studies failed to show decreases in overall annual treatment costs, given rising drug costs and increases in hospitalizations due to complications from, or resistance to, HAART and due to other diseases impacting HIV-infected patients. Although the lifetime costs of treating a person with HIV have also increased, this treatment has resulted in substantial gains in the length and quality of life for those living with HIV.

The Changing Pattern of Hospital Care for Persons Living With HIV

OBJECTIVE

To compare inpatient utilization and costs by persons living with HIV in 2000 with inpatient utilization and costs in 2004.

DATA SOURCES

Data on 91,343 hospital discharge abstracts representing all HIV-related admissions in 6 states (California, Florida, New Jersey, New York, South Carolina, and Washington state) in 2000 and data from 72,829 hospital discharge abstracts representing all HIV-related admissions in the same states in 2004 are used. These data were obtained from the Agency for Healthcare Research and Quality's Healthcare Cost and Utilization Project, and they were combined with data on the number of persons living with HIV that were obtained from the Centers for Disease Control and Prevention and 2 state departments of health.

STUDY DESIGN

This study compares the hospital care received by persons living with HIV in 6 states in calendar year 2000 with the hospital care received by persons living with HIV in calendar year 2004 in the same 6 states. This study also compares population-based measures of hospital utilization (ie, to measure the average utilization of hospital care per person living with HIV in each state) across the 6 states.

RESULTS

This study found that the average age of a hospitalized patient with HIV rose from 41 to 44 years and that the average number of diagnoses rose from 6.0 to 7.4. Moreover, it was found that the average number of admissions per person living with HIV fell 39% and that the percentages of female and black patients with HIV remained the same.

CONCLUSIONS

Hospitalized patients living with HIV are getting older and sicker, although the average number of admissions per person living with HIV continues to fall.

Distribution of health care expenditures for HIV-infected patients

BACKGROUND

Health care expenditures for persons infected with human immunodeficiency virus (HIV) in the United State determined on the basis of actual health care use have not been reported in the era of highly active antiretroviral therapy.

METHODS

Patients receiving primary care at the University of Alabama at Birmingham HIV clinic were included in the study. All encounters (except emergency room visits) that occurred within the University of Alabama at Birmingham Hospital System from 1 March 2000 to 1 March 2001 were analyzed. Medication expenditures were determined on the basis of 2001 average wholesale price. Hospitalization expenditures were determined on the basis of 2001 Medicare diagnostic related group reimbursement rates. Clinic expenditures were determined on the basis of 2001 Medicare current procedural terminology reimbursement rates.

RESULTS

Among the 635 patients, total annual expenditures for patients with CD4+ cell counts <50 cells/microL (36,533 dollars per patient) were 2.6-times greater than total annual expenditures for patients with CD4+ cell counts > or =350 cells/microL (13,885 dollars per patient), primarily because of increased expenditures for nonantiretroviral medication and hospitalization. Expenditures for highly active antiretroviral therapy were relatively constant at approximately 10,500 dollars per patient per year across CD4+ cell count strata. Outpatient expenditures were 1558 dollars per patient per year; however, the clinic and physician component of these expenditures represented only 359 dollars per patient per year, or 2% of annual expenses. Health care expenditures for patients with HIV infection increased substantially for those with more-advanced disease and were driven predominantly by medication costs (which accounted for 71%-84% of annual expenses).

CONCLUSIONS

Physician reimbursements, even with 100% billing and collections, are inadequate to support the activities of most clinics providing HIV care. These findings have important implications for the continued support of HIV treatment programs in the United States.

Hospital and outpatient health services utilization among HIV-infected adults in care 2000-2002

BACKGROUND

Rapid changes in HIV epidemiology and antiretroviral therapy may have resulted in recent changes in patterns of healthcare utilization.

OBJECTIVE

The objective of this study was to examine sociodemographic and clinical correlates of inpatient and outpatient HIV-related health service utilization in a multistate sample of patients with HIV.

DESIGN

Demographic, clinical, and resource utilization data were collected from medical records for 2000, 2001, and 2002.

SETTING

This study was conducted at 11 U.S. HIV primary and specialty care sites in different geographic regions.

PATIENTS

In each year, HIV-positive patients with at least one CD4 count and any use of inpatient, outpatient, or emergency room services. Sample sizes were 13,392 in 2000, 15,211 in 2001, and 14,403 in 2002.

MAIN OUTCOME MEASURES

Main outcome measures were number of hospital admissions, total days in hospital, and number of outpatient clinic/office visits per year. Inpatient and outpatient costs were estimated by applying unit costs to numbers of inpatient days and outpatient visits.

RESULTS

Mean numbers of admissions per person per year decreased from 2000 (0.40) to 2002 (0.35), but this difference was not significant in multivariate analyses. Hospitalization rates were significantly higher among patients with greater immunosuppression, women, blacks, patients who acquired HIV through drug use, those 50 years of age and over, and those with Medicaid or Medicare. Mean annual outpatient visits decreased significantly between 2000 and 2002, from 6.06 to 5.66 visits per person per year. Whites, Hispanics, those 30 years of age and over, those on highly active antiretroviral therapy (HAART), and those with Medicaid or Medicare had significantly higher outpatient utilization. Inpatient costs per patient per month (PPPM) were estimated to be 514 dollars in 2000, 472 dollars in 2001, and 424 dollars in 2002; outpatient costs PPPM were estimated at 108 dollars in 2000, 100 dollars in 2001, and 101 dollars in 2002.

CONCLUSION

Changes in utilization over this 3-year period, although statistically significant in some cases, were not substantial. Hospitalization rates remain relatively high among minority or disadvantaged groups, suggesting persistent disparities in care. Combined inpatient and outpatient costs for patients on HAART were not significantly lower than for patients not on HAART.

Inappropriate drug combinations among privately insured patients with HIV disease

OBJECTIVE

The objective of this study was to examine inappropriate drug combinations among privately insured patients with HIV disease.

DATA

Data were obtained from the MarketScan Commercial Claims and Encounter Database for the years 1999 and 2000.

METHODS

Each of the 2110 person-years of data examined in this study represents the claims experience of an enrollee with HIV disease who filled an antiretroviral medication prescription in either 1999 or 2000 for a protease inhibitor or nonnucleoside reverse transcription inhibitor. This study compares the claims experience of patients with HIV who filled a prescription for an inappropriate drug combination as specified in guidelines jointly issued by the U.S. Department of Health and Human Services and the Henry J. Kaiser Family Foundation with the claims experience of patients who did not.

RESULTS

An inappropriate drug combination was found in approximately 2% of the person-years of data, and persons who experienced an inappropriate drug combination had higher claims costs. One half of all of the inappropriate drug combinations involved a single lipid-lowering agent (simvastatin). Protease inhibitors decrease the activity of the enzyme that metabolizes simvastatin, and high concentrations of simvastatin have been associated with muscle damage. We found that patients who received protease inhibitors and simvastatin were more likely to experience muscle damage.

CONCLUSION

Persons with HIV have compromised immune systems and often take many medications. Thus, the risk and consequences of medication errors are severe, and both providers and patients should carefully monitor drug regimens to ensure that they are both safe and efficacious.

Hospital and Outpatient Health Services Utilization Among HIV-Infected Children in Care 2000–2001

BACKGROUND

The aging of the pediatric HIV cohort and advances in antiretroviral therapy for children may have resulted in recent changes in patterns of healthcare utilization.

OBJECTIVES

The objectives of this study were to examine inpatient and outpatient HIV-related health service utilization in a multistate sample of HIV-infected children, and to assess sociodemographic and clinical correlates of utilization.

DESIGN

Cohort study of pediatric patients with HIV. Demographic, clinical, and resource utilization data were collected from medical records for 2000 and 2001.

SETTING

This study was conducted at 4 U.S. HIV primary pediatric and specialty care sites in different geographic regions.

PATIENTS

Three hundred three HIV-positive children with at least one outpatient visit or CD4 test in either 2000 or 2001 were studied.

MAIN OUTCOME MEASURES

Mean outcome measures were number of hospital admissions, mean length of hospital stay, and number of outpatient clinic/office visits.

RESULTS

Hospitalization rates decreased significantly from 39.2 (95% confidence interval [CI], 28.4-50.1) to 25.3 (95% CI, 16.4-34.3) admissions per 100 patients between 2000 and 2001. Hospitalizations were higher among patients with greater immunosuppression, those 2 years and under, and those with AIDS, but were not significantly related to receipt of highly active antiretroviral therapy. Mean outpatient visits did not change significantly between 2000 and 2001 from 9.09 (95% CI, 8.3-9.9) to 9.06 (95% CI, 8.4-9.7) visits per child per year. Children 2 years and under, those on highly active antiretroviral therapy, those with AIDS, and those with Medicaid had significantly higher outpatient utilization. Those with higher HIV-1 RNA had higher outpatient utilization than those with less advanced disease.

CONCLUSION

Inpatient utilization significantly decreased between 2000 and 2001, but outpatient utilization did not change over time. Compared with prior studies, utilization rates appear to be declining over time. Unlike adults, racial/ethnic or gender disparities in healthcare utilization are less pronounced for HIV-infected children.

Antiretroviral therapy and health care utilization: a study of privately insured men and women with HIV disease

OBJECTIVE

To compare the use of antiretroviral therapy and other health care resources by women and men with HIV disease who are privately insured.

DATA SOURCES

Data were obtained from the MarketScan Commercial Claims and Encounter Database produced by the Medstat Group, Inc., of Ann Arbor, Michigan. This database includes eligibility files as well as claims data for inpatient care, outpatient care, physician services, and prescription drugs for enrollees in employer-sponsored benefit plans for 24 large employers around the nation.

STUDY DESIGN

Examine utilization by 2,026 privately insured persons (1,494 men and 532 women) with HIV disease in calendar year 2000 under the age of 65.

PRINCIPAL FINDINGS

Using a simple comparison, we found that 71 percent of men (68.7 to 73.3 percent is 95 percent confidence interval) and 39 percent of women (35.1 to 43.5 percent is 95 percent confidence interval) with HIV disease received antiretroviral therapy. We also found that the average annual drug cost was $9,037 for a man ($8,372 to $9,702 is 95 percent confidence interval) and $3,893 for a woman ($3,476 to $4,490 is 95 percent confidence interval). Furthermore, we found that the out-of-pocket expenses comprised 10 percent of total expenses for men ($1,617 out of $16,405) and 4 percent for women ($405 out of $10,397).

CONCLUSION

There are major differences in the utilization and cost of health care between privately insured men and women with HIV disease.

Economic costs to business of the HIV/AIDS epidemic

HIV infection is a devastating disease for individuals and society. The economic burden of employees with HIV infection is a matter of increasing concern for employers. The purpose of this paper was to conduct a comprehensive review of published studies which measured/estimated economic costs incurred by HIV-infected employees, and evaluate the potential economic impact of the HIV/AIDS epidemic on business in different countries. This review finds a conceptual consensus in the literature that suggests that the HIV/AIDS epidemic has a potentially sizable economic cost to business, primarily due to increased costs for employment-based insurance premiums, welfare benefits, lost productivity, new hiring and training, and a downsized economy and labour market. Based on published data in the US, accounting for the first three major cost items, in 2002 an HIV-infected worker would cost an employer in the US an estimated 37,320 US dollars for asymptomatic individuals and 50,374 US dollars for symptomatic individuals per person-year. However, this review found little consistent empirical data in the literature regarding the scale of disease costs specific to businesses in different settings. In addition, the current literature offers little guidance in terms of well designed, validated, and easily replicated analytical frameworks for conducting a comprehensive cost analysis from a business perspective. Future research is needed to improve both the theoretical modelling and empirical work in assessing the full economic impact of the HIV/ADIS epidemic on patients, businesses and society at large.

Hospital and outpatient health services utilization among HIV-infected patients in care in 1999

BACKGROUND

The evolving epidemiology and therapeutic management of HIV disease has important implications for health care resource utilization in HIV-infected patients, and health care resource use data are also needed to support policy and financial decision making.

METHODS

Demographic, clinical, and resource utilization data were collected from 9 U.S. HIV primary and specialty care sites in calendar year 1999. Rates of resource use were calculated for hospital admission, length of hospital stay, and outpatient clinic/office visits.

RESULTS

The sample included 5255 patients from HIV primary care sites in 3 eastern, 3 midwestern, and 3 western areas of the United States. Hospital admissions accounted for an annual mean of 297 days per 100 persons/y in 1999. Hospital days ranged from a low of 165 per 100 persons/mo for a CD4 > 500 cells/mm(3) to 840 per 100 persons/mo for a CD4 < 50 cells/mm(3) (p <.01). Mean annual outpatient clinic/office visits were 10.7 per person in 1999. A declining CD4 level and an increasing HIV-1 RNA level were both associated with higher hospital and outpatient utilization. HAART use was associated with fewer hospital days, and a higher outpatient visit rate. Injecting drug use risk was associated with an increase in hospital days. African American race was associated with a higher number of hospital days, but a lower outpatient visit rate. Female gender was associated with higher outpatient utilization. Mean monthly inpatient and outpatient expenditures in 1999 were $423 and $168, respectively.

CONCLUSION

As HIV care continues to evolve, data from our network of HIV providers will be useful in quantifying changes in HIV health services utilization to guide policy makers, as well as HIV care payers and providers.

Lifetime Cost of HIV Care in France during the Era of Highly Active Antiretroviral Therapy

Objective

To estimate the treatment and health care costs of HIV infection or AIDS in France during the era of highly active antiretroviral therapy (HAART).

Design

We used a clinical database of HIV-infected patients to calculate the resource use and cost of care for different stages of HIV infection. Costs were incorporated into a computer-based, probabilistic simulation model of the natural history and treatment of HIV infection to estimate the lifetime cost of treating patients with HIV disease.

Setting

A northern France HIV clinical cohort.

Participants

1232 HIV-infected patients followed from January 1994 through July 1998.

Results

In the absence of an AIDS-defining event, the average total cost of care ranged from 670 euros (1 euro=US $1.19) per person-month in the highest CD4 stratum (>500/μl) to 1060 euros per person-month in the lowest CD4 stratum (≤50/μl). The mean cost of care was estimated at 3370 euros per person-month during the initial months around the occurrence of an AIDS-defining event; at 1750 euros per person-month during the period spanning from 2 months after the diagnosis of specific AIDS-defining event to 1 month prior to death; and at 13 010 euros per person-month in the final month prior to death. If clinical management of HIV infection began at a CD4 cell count of 378/μl, as in this cohort, the discounted lifetime cost of treating an HIV-infected French patient was estimated at 214 000 euros. The undiscounted costs were 309 000 euros over a projected life expectancy of 16.4 years.

Conclusion

The cost of HIV disease varies widely depending upon the stage of illness. These estimates of stage-specific and lifetime costs of HIV care will assist health policy planners in assessing the burden of disease in the era of HAART and projecting future resource requirements.

Location, race, and hospital care for AIDS patients: an analysis of 10 states

This study is the first statewide comparison of hospital utilization and inpatient mortality rates for people with acquired immune deficiency syndrome (AIDS). Data from 120,772 hospital discharge abstracts for all AIDS-related admissions in 10 states (California, Colorado, Florida, Iowa, Kansas, Maryland, New Jersey, New York, Pennsylvania, and South Carolina) in 1996 were combined with data on the number and the racial and ethnic characteristics of all people living with AIDS (PLWAs) in each state. These data were used to derive population-based estimates of the use of hospital services per PLWA and of inpatient mortality rates in each state. Multivariate analyses examined sources of variation in inpatient length of stay and inpatient mortality. The primary finding of this study is that hospital utilization rates and inpatient mortality rates for people with AIDS vary substantially across states and among racial and ethnic groups within states even after adjusting for severity of illness. Blacks and Hispanics had longer hospital stays and were more likely to die in the hospital than whites. State-level policies, such as home and community-based waiver programs and enhanced HIV reimbursement rates, significantly affected hospital use.

Cost-effectiveness of earlier initiation of antiretroviral therapy for uninsured HIV-infected adults

OBJECTIVES

This study was designed to examine the societal cost-effectiveness and the impact on government payers of earlier initiation of antiretroviral therapy for uninsured HIV-infected adults.

METHODS

A state-transition simulation model of HIV disease was used. Data were derived from the Multicenter AIDS Cohort Study, published randomized trials, and medical care cost estimates for all government payers and for Massachusetts, NewYork, and Florida.

RESULTS

Quality-adjusted life expectancy increased from 7.64 years with therapy initiated at 200 CD4 cells/microL to 8.21 years with therapy initiated at 500 CD4 cells/microL. Initiating therapy at 500 CD4/microL was a more efficient use of resources than initiating therapy at 200 CD4/microL and had an incremental cost-effectiveness ratio of $17,300 per quality-adjusted life-year gained, compared with no therapy. Costs to state payers in the first 5 years ranged from $5,500 to $24,900 because of differences among the states in the availability of federal funds forAIDS drug assistance programs.

CONCLUSIONS

Antiretroviral therapy initiated at 500 CD4 cells/microL is cost-effective from a societal: perspective compared with therapy initiated later. States should consider Medicaid waivers to expand access to early therapy.

Health and federal budgetary effects of increasing access to antiretroviral medications for HIV by expanding Medicaid

OBJECTIVES. This study modeled the health and federal fiscal effects of expanding Medicaid for HIV-infected people to improve access to highly active antiretroviral therapy.

METHODS

A disease state model of the US HIV epidemic, with and without Medicaid expansion, was used. Eligibility required a CD4 cell count less than 500/mm3 or viral load greater than 10,000, absent or inadequate medication insurance, and annual income less than $10,000. Two benefits were modeled, "full" and "limited" (medications, outpatient care). Federal spending for Medicaid, Medicare, AIDS Drug Assistance Program, Supplemental Security Income, and Social Security Disability Insurance were assessed.

RESULTS

An estimated 38,000 individuals would enroll in a Medicaid HIV expansion. Over 5 years, expansion would prevent an estimated 13,000 AIDS diagnoses and 2600 deaths and add 5,816 years of life. Net federal costs for all programs are $739 million (full benefits) and $480 million (limited benefits); for Medicaid alone, the costs are $1.43 and $1.17 billion, respectively. Results were sensitive to awareness of serostatus, highly active antiretroviral therapy cost, and participation rate. Strategies for federal cost neutrality include Medicaid HIV drug price reductions as low as 9% and private insurance buy-ins.

CONCLUSIONS

Expansion of the Medicaid eligibility to increase access to antiretroviral therapy would have substantial health benefits at affordable costs.

Long-term impact of highly active antiretroviral therapy on HIV-related health care costs

CONTEXT

Highly active antiretroviral therapy (HAART) is associated with decreased opportunistic infections, hospitalization, and HIV-related health care costs over relatively short periods of time. We have previously demonstrated that decreases in total HIV cost are proportional to penetration of protease inhibitor therapy in our clinic.

OBJECTIVE

To determine the effects of HAART on HIV health care use and costs over 44 months.

SETTING

A comprehensive HIV service within a Veterans Affairs Medical Center.

DESIGN

A cost-effectiveness analysis of HAART.

MAIN OUTCOME MEASUREMENTS

The mean monthly number of hospital days, infectious diseases clinic visits, emergency room visits, non-HIV-related outpatient visits, inpatient costs, and antiretroviral treatment costs per patient were determined by dividing these during the period from January 1995 through June 1998 into four intervals. Viral load tests were available from October 1996. Cost-effectiveness of HAART was evaluated by determining the costs of achieving an undetectable viral load over time.

RESULTS

Mean monthly hospitalization and associated inpatient costs decreased and remained low 2 years after the introduction of protease inhibitors (37 hospital days per 100 patients). Total cost decreased from $1905 per patient per month during the first quarter to $1090 per patient per month in the third quarter but increased to $1391 per patient per month in the fourth quarter. Antiretroviral treatment costs increased throughout the entire observation period from $79 per patient per month to $518 per patient per month. Hospitalization costs decreased from $1275 per patient per month in the first quarter to less than $500 per patient per month in each of the third and fourth quarters. The percentage of patients with a viral load <500 copies/mL increased from 21% in October 1996 to 47% in June of 1997 (p =.014). The cost of achieving an undetectable viral load decreased from $4438 per patient per month to $2669 per patient per month, but this trend did not reach statistical significance (p =.18).

CONCLUSIONS

After an initial decrease, there was an increase in the total monthly cost of caring for HIV patients. Cost increases were primarily due to antiretroviral treatment costs, but these costs were offset by a marked decrease in inpatient-related costs. Increases in costs were not related to antiretroviral treatment failures as measured by the proportion of patients with low or undetectable viral loads. The cost of achieving an undetectable viral load remained stable despite increases in the cost of procuring antiretroviral agents.

The cost of HIV treatment and care. A global review

This review of published studies on the costs of HIV treatment and care describes some of the recent developments that have influenced these costs in industrialised and industrialising countries, especially within the context of changing drug treatments. Some of the different approaches to estimating the economic impact of HIV infection are briefly presented. The methods used to review the literature are described, particularly the criteria of a scoring system that was specifically developed to systematically screen some of the studies identified. The mean review score for studies dealing with direct hospital costs increased significantly (p = 0.003) over the 3 periods analysed (before 1987, 1987 to 1995, and 1996 and beyond), indicating that the overall 'quality' of studies increased over time. All cost estimates, other than those from non-industrialised regions, were converted to 1996 US dollars using country-specific total health expenditure inflaters and country-specific Gross Domestic Product Purchasing Power Parity converters. A summary of hospital cost estimates over time and by region demonstrated that the costs of treating asymptomatic individuals and people with symptomatic non-AIDS increased over the period, but that the costs of treating individuals with AIDS appears to have stabilised since the late 1980s. As fewer studies could be identified on the costs of community and informal care, indirect productivity costs and population cost estimates, and costs of care for children with HIV infection, all of these studies were reviewed without the use of the scoring system. Finally, the discussion explores the evidence on the global costs of HIV in non-industrialised economies and the affordability of HIV treatment and care. Some suggestions for the direction of future HIV costing studies are also presented. A need remains for good quality cost data. Adequate research effort should be directed to improving the scope and quality of information on costs of HIV service provision around the world.

Healthcare Economics in HIV

In an era of cost-consciousness in the delivery of medical care, the economics of healthcare delivery for HIV-infected persons has been an area of active interest. Interested parties include the payors of HIV care, particularly public insurers, who are paying for an increasing amount of the overall cost of HIV care in the US; providers of care, many of whom are finding it increasingly difficult to provide HIV care in a capitated market; and those persons who are HIV-infected and increasingly caught in the economic turmoil of the HIV healthcare marketplace. This paper will review the literature published over the past year regarding the economics of healthcare for HIV in the US.

Effect of antiretroviral therapy on the incidence of bacterial pneumonia in patients with advanced HIV infection

To determine the relationship of combination antiretroviral therapy and bacterial pneumonia, we assessed incidence of and risk factors for bacterial pneumonia in 1,898 human immunodeficiency virus (HIV)-infected patients with CD4 cell counts < 200/mm(3) followed in the Johns Hopkins HIV clinic between 1993 and 1998. A total of 352 episodes of bacterial pneumonia occurred during 2,310 patient-years of follow-up. Incidence of bacterial pneumonia decreased from 22.7 episodes/100 person-years (py) in the first half of 1993 to 12.3 episodes/100 py in the first half of 1996, reaching a nadir of 9.1 episodes/100 py in the second half of 1997 (p < 0.05). The use of protease inhibitor-containing regimens was associated with a decreased risk of bacterial pneumonia (risk ratio [RR] 0.55, 95% CI 0.31 to 0.94). Lower CD4 cell counts (RR 2.22, 95% CI 1.54 to 3.18), injection drug use as HIV transmission category (RR2.0, 95% CI 1.43 to 2.76), and prior Pneumocystis carinii pneumonia (RR 3.88, 95% CI 1.65 to 9.16) were also significantly associated with bacterial pneumonia. Trimethoprim-sulfamethoxazole and macrolide use were not significantly associated with risk of bacterial pneumonia. There has been a dramatic decline in the incidence of bacterial pneumonia resulting from the use of combination antiretroviral therapy containing protease inhibitors.

Impact of zidovudine-based triple combination therapy on an AIDS drug assistance program

A static deterministic model was used to estimate the effect of the shift to a triple combination therapeutic standard on the annual AIDS Drug Assistance Program (ADAP) budget, total medical care expenditures, and population health outcomes for New York (NY) state ADAP enrollees. The model used opportunistic disease incidence data from the Multicenter AIDS Cohort Study (MACS) and other studies. Costs of treating opportunistic infections (OIs) and other HIV complications with each type of therapy were derived from treatment algorithms and standard unit costs. CD4+ cell counts were used as an index of need for OI prophylaxis and for determining OI incidence. Treatment with zidovudine-based combination therapy has been shown to increase CD4+ cell counts and reduce OI incidence. The model estimated that a change from monotherapy to triple therapy would have increased NY ADAP budget expenditures per enrollee by 115%. However, total medical system costs per ADAP enrollee (including ADAP costs) would decrease by 0.4% in the base case as a result of reduction in OIs and other HIV sequelae and associated costs. Results are sensitive to the assumed percentage of people taking combination therapy as well as to the assumptions made about the impact of the combination therapy on CD4+ cell count. Total ADAP budget impacts will depend on the growth in ADAP enrollment as a result of the availability of more effective therapies. In conclusion, this model demonstrates how access to newer, more effective HIV drug treatments can reduce the costs of treating OIs and provide major health benefits for ADAP enrollees.

Cost effectiveness of combination HIV therapy: 3 years later

Since 1997, expert panel guidelines for HIV care have recommended the use of combination antiretroviral therapy with at least 3 antiretroviral drugs. Several studies have examined the cost effectiveness of 3-drug combination antiretroviral regimens for the treatment of HIV infection. Analyses comparing a 3-drug protease inhibitor-containing regimen with a 1- or 2-drug non-nucleoside reverse transcriptase inhibitor regimen have consistently yielded incremental direct cost estimates ranging from $US10,000 to just over $US13,000 per year of life saved. In Western societies, such an incremental cost per year of life saved compares favourably with chronic therapy for other diseases and argues for the adoption of these drugs by payors and policy makers. The reason for this favourable cost-effectiveness ratio appears to be the decrease in opportunistic complications and hospitalisation associated with the effective use of combination antiretroviral therapy. Whether this initial benefit will be maintained is not yet known. Other comorbid illnesses such as hepatitis C or renal failure may subsequently increase the cost of HIV care, and some analyses suggest that resistance may develop to these drugs over the long term. In addition, studies are needed to assess the cost effectiveness of these therapies in developing countries where the expense of these drugs appears to put them out of reach. The collection and analysis of economic data will continue to be needed as newer HIV therapies become available and the HIV healthcare environment evolves. Quantifying medical care costs and calculating cost effectiveness involve assessing a moving target. Economic analyses of HIV infection must evolve in tandem with therapeutic changes to continue to be relevant to policy makers, payors of care, and those who provide and receive HIV care.

Access to HIV services by the urban poor

This paper examines the effect of HIV-health status and HIV-transmission mode on access to HIV-related services among African Americans, Hispanics and White HIV+ individuals. Data were collected from 169 African Americans, 72 Hispanics and 253 White HIV+ individuals seeking 8 social and 6 medical HIV services at 29 public and community-based organizations in Houston, Texas. A total of 42 separate logistic regressions were estimated for each HIV service and for each race/ethnic group. The results showed significant differences in access to HIV social services based on HIV-transmission mode among the three race/ethnic groups, but no significant differences were found in access to medical services based on either HIV status or HIV-transmission mode among the three race/ethnic groups.

How good are US studies of HIV costs of care?

BACKGROUND

Valid, timely estimates of the costs of HIV care are needed by health planners and policy makers.

OBJECTIVE

To perform a methodologic critique of published estimates of resource utilization and costs of HIV care.

DATA SOURCES

MEDLINE database for 1990-1998.

DATA SELECTION

Included articles focused on adults with a spectrum of HIV disease in which the authors developed their own resource use and cost data. Thirty one articles met these criteria.

DATA EXTRACTION

Studies were compared based on: (1) utilization and cost estimates, in 1995 dollars; (2) study period; (3) research design; (4) sampling frame; (5) sample size and patient characteristics; (6) data sources and scope of services; and (7) methods used in the analysis.

DATA SYNTHESIS

The most recent estimates pertain to the first half of 1995, before the use of protease inhibitor therapy. We found wide variations in the estimates and identified three major sources for this: (1) patient samples that were restricted to subgroups of the national HIV-infected population; (2) utilization data that were limited in scope (e.g., inpatient care only); and (3) invalid methods for estimating annual or lifetime costs, particularly in dealing with decedents.

CONCLUSIONS

To accurately estimate resource use and costs for HIV care nationwide, a nationally representative probability sample of HIV-infected patients is required. Even in research that is not intended to provide national estimates, the scope of utilization data should be broadened and greater attention to methodologic issues in the analysis of annual and lifetime costs is needed.

Costs of HIV medical care in the era of highly active antiretroviral therapy

OBJECTIVES

In the USA, Medicaid is the principal payer of the health care costs of patients with HIV infection. We wished to determine how the costs to Medicaid of patients in Maryland infected with HIV have changed in the setting of highly active antiretroviral treatment.

DESIGN

Observational cohort study.

METHODS

Analysis of combined economic and clinical data of patients from the Johns Hopkins HIV Service, the provider of primary and sub-specialty care for a majority of HIV-infected patients in the Baltimore metropolitan region. All patients were enrolled in Medicaid and received care longitudinally in Maryland from 1 January 1995 through 31 December 1997. Monthly Medicaid payments were calculated for all inpatient and outpatient services by fiscal year, CD4 cell count, and use of protease inhibitors.

RESULTS

For inpatients with a CD4 cell count < or = 50 x 10(6) cells/l, the total health care average monthly payments remained unchanged ($2629 in 1995, $2585 in 1997). Total mean monthly payments increased for those with a CD4 cell count > 50 x 10(6) cells/l (CD4 cell count 50-200 x 10(6) cells/l, $1172 in 1995 and $1615 in 1997, P < 0.05; CD4 cell count 201-500 x 10(6) cells/l, $1078 in 1995 and $1305 in 1997, P < 0.05). However, when data were stratified according to use of a protease inhibitor-containing regimen (used during approximately 50% of follow-up time in 1996-1997) it was found that hospital inpatient payments decreased significantly in all CD4 strata for patients on a protease inhibitor-containing regimen whereas pharmacy payments increased significantly. Inpatient payments associated with treating opportunistic illness were lower in 1996-1997 for patients receiving protease inhibitor therapy compared with those not receiving protease inhibitors. On balance, total health care payments tended to be slightly lower for patients receiving a protease inhibitor regimen.

CONCLUSION

Although protease inhibitor-containing antiretroviral regimens are being used by only about half of our Medicaid-insured patients, when they are used, there are significantly lower hospital inpatient and community care costs, as well as lower costs associated with the treatment of opportunistic illness. Even with the concurrent increase in their pharmacy costs, total health care costs were stable or slightly lower for these patients. We believe this is a favorable result suggesting a good clinical value being achieved without an increase in costs.

Demograghic and socio-economic determinants of community and hospital services costs for people with HIV/AIDS in London

We examined the influence of demographic, social and economic background of people with HIV/AIDS in London on total community and hospital services costs. This was a retrospective study of community and hospital service use, needs and costs based on structured questionnaires administered by trained interviewers and costing information obtained from the service purchasers and providers, based on two Genito-urinary Medicine clinics in London: the Jefferiss Wing at St. Mary's Hospital and Patric Clements at the Central Middlesex Hospital, London, England. The subjects were 225 HIV infected patients (105 asymptomatic, 59 symptomatic non-AIDS and 61 AIDS). We found that over and above well established determinants of health care costs for HIV infected people such as disease stage and transmission category, social and economic factors such as employment and support of a living-in partner significantly reduced community services costs. Private health insurance had a similar effect, though only a small proportion of HIV people had such cover. The cost of community services for HIV infected non-European Union nationals, mainly of African origin, was one quarter that for the European Union nationals. Community services costs were highest for heterosexually infected women and lowest for heterosexually infected men after adjusting for other factors. Hospital services costs were significantly higher for HIV infected people lacking educational qualifications and employment. We conclude that access to community care for HIV infected non-EU nationals appears to be very poor as the cost of their community services was one quarter that for the EU nationals after adjusting for the effects of transmission category, disease stage, living with a partner, employment and having a private health insurance. Additional incentives for informal care for HIV infected people could be a cost-effective way to improve their community health service provisions.

Protease inhibitor-based therapy is associated with decreased HIV-related health care costs in men treated at a Veterans Administration hospital

BACKGROUND

Protease inhibitor (PI) therapy for HIV infection is associated with decreased rates of opportunistic infections and death. Statistical models predict that decreased complications will be associated with decreased hospitalization costs. A recent report suggested that the decrease in the HIV hospitalization costs were offset by increases in demand for outpatient services. We performed a study of hospital use and HIV-associated health care costs in our center to determine the following: whether PI therapy is associated with decreased inpatient use; whether PI therapy is associated with decreased outpatient use and costs; whether decreased HIV health care costs are associated with increased use of nucleoside analogues.

METHODS

The Dallas Veteran Affairs Medical Center provides comprehensive inpatient and outpatient HIV care and thus can evaluate the relation between inpatient and outpatient costs. The mean monthly number of hospital days, Infectious Diseases clinic visits, emergency department visits, other outpatient clinic visits, inpatient costs, outpatient costs, and PI costs were determined from January 1, 1995 through July 31, 1997. This time period was then divided into three intervals. Comparisons of PI use and HIV-related health care costs were during the three intervals was performed using analysis of variance (ANOVA). Significant differences between the baseline characteristics were further analyzed through multiple linear regression.

RESULTS

A decrease in hospital days, and all outpatient visits including emergency visits, and HIV clinic visits was determined. No difference was found in the rate of use of other outpatient services. The per patient costs of HIV care decreased from a monthly average of $1905 U.S. in the first interval to $1122 U.S. in the last interval (p < .01). Linear regression demonstrated an inverse relation between PI use and total HIV costs (B=-0.67, p=.00, adjusted R2=0.52) but no relation between nucleoside use, stage of disease or financial class.

CONCLUSIONS

PI therapy is associated with decreased hospital days and use of outpatient services. Total patient costs decreased, but a concomitant rise in outpatient costs took place. This increase was primarily a result of increased costs of acquiring PI. Increases in the number of nucleoside agents prescribed were not associated with decreased costs.

Consistency in maintaining contact with HIV-related service providers: an analysis of the AIDS Cost and Services Utilization Study (ACSUS)

Patients (n = 1949) infected with HIV were recruited for the AIDS Cost & Service Utilization Survey (ACSUS) from ten U.S. cities and administered face to face interviews at three month intervals over an 18 month period from March 1, 1991 to August 31, 1992. The interview was designed to obtain information at each wave of data collection on the use of the following services: ambulatory care, hospitalization, emergency room use, support groups/counseling, drug and alcohol treatment, and dental care. Patients were found to be highly consistent in their patterns of utilization across time, regardless of the service in question. Of the patients who reported using an emergency room (ER) at Time 1, 52% also reported using an ER during the next three months later at Time 2. Of those who reported having been hospitalized during the Time 1 reporting period, almost 58% reported a hospitalization again at Time 2. Next, use of a service at Time 6 (n = 1404, 72.2%) was regressed onto whether the person received the service at Time 2 and the personal, financial, and medical variables. Except for dental services, utilization of a service one year in the past (Time 2) was the strongest predictor of Time 6 use. The findings indicated that the one factor consistently related to service use within this sample is a factor (as opposed to education, race, or even insurance) that is amenable to intervention: previous use of that service. The individuals studied established patterns of service utilization that are of reasonably long duration once they began use of a service. This continuity of care becomes more critical as the initiation of treatments begins with the diagnosis of HIV rather than AIDS. Findings suggest that HIV outreach efforts be targeted to increasing early use of medical and behavioral services in ambulatory care settings.

Evaluating the cost of medications for ambulatory HIV-infected persons in association with landmark changes in antiretroviral therapy

Costs of medications for ambulatory HIV-infected people increase as knowledge of antiretroviral therapy and therapy for opportunistic infection grows. We evaluated the evolution of drug costs for HIV-infected persons who attend a university clinic in Baltimore, Maryland. Cross-sectional abstracts of a cohort of patients for four periods, corresponding to landmark changes in therapy, who attended the clinic between June 1995 and September 1996 were obtained. Monthly medication costs for all patients were calculated. Mean costs increased significantly (p < .01) from period 1 ($447 U.S.) to period 4 ($1048 U.S.). Multivariate analysis only revealed higher costs for patients with a CD4+ count <200 cells/mm3 (p < .001). The proportion of costs attributable to antiretroviral therapy increased from 34% in period 1 to 53% in period 4. Combination therapy increased >10-fold, from 8% in period 1 to 94% in period 4. Protease inhibitor use also increased significantly, from 4% in period 2 to 53% in period 4. We quantified the increase in costs of medications from mid-1995 to late 1996. Increases in costs appear to be the result of increasing complexity of drug regimens, particularly antiretroviral therapy in combinations.

Cost-utility analysis of prophylactic treatment with oral ganciclovir for cytomegalovirus retinitis

OBJECTIVE

Cytomegalovirus (CMV) retinitis is a relatively common opportunistic infection in late-stage HIV disease, causing significant morbidity and mortality. Prophylactic use of oral ganciclovir has recently been shown to decrease the incidence of CMV retinitis but is relatively expensive and may not be very well tolerated by many patients. We performed a decision analysis to assess the cost-effectiveness of prophylactic oral ganciclovir therapy.

METHODS

A decision analysis using a Markov approach compared absence of prophylaxis and prophylaxis with oral ganciclovir. Estimates of effectiveness of prophylaxis and costs of illness were obtained from published literature. Drug costs were based on national average wholesale prices. All health care costs were based on 1996 U.S. dollars. Sensitivity analyses were done over ranges of estimates of cost and effectiveness.

RESULTS

Using our baseline estimates of cost and effectiveness, use of oral ganciclovir prophylaxis in patients with CD4 counts <50 cells/mm3 would be associated with average lifetime health care costs of $104,746, compared with $90,985 for no prophylaxis. Using oral ganciclovir, the average quality-adjusted life-years (QALYs) would be 2.05, and the CMV retinitis-free life-years would be 1.64, compared with 1.87 and 1.27, respectively, for no prophylaxis. The incremental cost-utility of oral ganciclovir is $76,676 per year of life saved and $37,542 per year of additional CMV retinitis-free life. Oral ganciclovir would become more cost-effective relative to no prophylaxis if the probability of CMV retinitis while taking oral ganciclovir declined. Oral ganciclovir would be less cost-effective if the cost of treating CMV retinitis declines, if our estimates of quality of life are low, or if the overall incidence of CMV retinitis declines.

CONCLUSIONS

Oral ganciclovir is a less cost-effective approach than several other interventions used for HIV-disease prophylaxis. It would potentially become cost-effective if it is possible to target oral ganciclovir prophylaxis to patients who are most likely to benefit.