摘要：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 5816 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. Antiretroviral therapy dramatically slows the progression of HIV disease and AIDS. Multiple clinical studies have reported that triple therapy with 2 nucleoside analogues and a protease inhibitor or nonnucleoside reverse transcriptase inhibitor—known as highly active antiretroviral therapy —sharply depresses viral load, improves CD4 cell counts, and delays clinical progression to AIDS and death. 1 – 4 Although there is now hope that HIV/AIDS can be a manageable chronic disease, 5 , 6 clinical efficacy has not been matched by access to and use of therapy. Approximately 750 000 individuals in the United States are infected with HIV, 7 most of whom likely meet the broad criteria for being offered highly active antiretroviral therapy (CD4 cell count < 500/mm3, viral load > 10 000 HIV RNA copies/mL, or symptoms). Yet, evidence from clinical settings suggests that highly active antiretroviral therapy is used by only about 200 000 individuals. 8 Reasons for limited use include lack of awareness of infection, physician failure to initiate treatment, provider or patient preference to postpone treatment, patient difficulty with adherence or uncomfortable side effects, and development of drug resistance. 6 One critical barrier is financial. Many individuals lack adequate medical insurance or the financial resources to afford the $12 000 or more annual cost of highly active antiretroviral therapy, 9 – 13 and competing financial demands are associated with reduced antiretroviral use. 14 Several public programs attempt to improve financial access to care. Medicaid, with funding shared by the federal government and the states, is the largest payer of health care for persons with HIV/AIDS, accounting for $3.9 billion in fiscal year 1999 and covering 46% of all patients with HIV in care. 15 , 16 Medicaid eligibility requires individuals to have low income and to match an eligibility category. Most persons with HIV/AIDS qualify for Medicaid by meeting the disability and income criteria of the federal Supplemental Security Income cash assistance program for persons who are aged, blind, or disabled. However, people in the early stages of HIV disease, for whom highly active antiretroviral therapy may be indicated and may prevent disability, face the catch-22 of having eligibility postponed until they become disabled. Other public programs increase access to HIV medications for those with lower incomes. The most important is the AIDS Drug Assistance Program (ADAP) of the federal Ryan White CARE Act. Unlike Medicaid, which is an entitlement program, the Ryan White Act requires annual appropriations; fiscal year 1998 funding for ADAP was $510 million, about two-thirds federal and one-third state. State ADAPs have faced repeated funding crises because of increasing demands from current and prospective enrollees. 17 ADAP has 2 significant limitations: adequate program funding to meet rising need depends each year on political support in Congress, and ADAP pays almost exclusively for prescription medications, not the full range of health care required by people with HIV. One approach to lessen financial barriers to earlier HIV care and highly active antiretroviral therapy is expanding Medicaid eligibility for individuals with early HIV disease, before disability. 18 However, federal policy requires that, absent legislated changes, modifications to eligibility or benefits be budget neutral to Medicaid: total program costs cannot exceed those expected without a modification. Preliminary federal analyses concluded that for an HIV expansion, budget neutrality for Medicaid was unlikely, stalling efforts to expand eligibility for HIV. 19 We undertook our analysis to assess more comprehensively the likely health and federal fiscal effects of a Medicaid eligibility expansion for people with HIV disease. Specifically, we designed a model to quantify an expansion's effect on the use of highly active antiretroviral therapy and consequently on AIDS diagnoses, deaths, and years of life. We estimated federal fiscal effects for a range of federal programs: Medicaid and 4 other health and income support programs that support significant numbers of persons with HIV/AIDS. We also examined several strategies to reduce or eliminate net federal costs and net costs to Medicaid over a 5-year time frame.
