Improved birth outcomes among HIV-infected women with enhanced Medicaid prenatal care.

OBJECTIVES: This study evaluated the impact of enhanced prenatal care on the birth outcomes of HIV-infected women. METHODS: Medicaid claims files linked to vital statistics were analyzed for 1723 HIV-infected women delivering a live-born singleton from January 1993 to October 1995. Prenatal care program visits were indicated by rate codes. Logistic models controlling for demographic, substance use, and health care variables were used to assess the program's effect on preterm birth (less than 37 weeks) and low birthweight (less than 2500 g). RESULTS: Of the women included in the study, 75.3% participated in the prenatal care program. Adjusted program care odds were 0.58 (95% confidence interval [CI] = 0.42, 0.81) for preterm birth and 0.37 (95% CI = 0.24, 0.58) for low-birthweight deliveries in women without a usual source of prenatal care. Women with a usual source had lower odds of low-birthweight deliveries if they had more than 9 program visits. The effect of program participation persisted in sensitivity analyses that adjusted for an unmeasured confounder. CONCLUSIONS: A statewide prenatal care Medicaid program demonstrates significant reductions in the risk of adverse birth outcomes for HIV-infected women.

Sources of prenatal care data and their association with birth outcomes of HIV-infected women.

OBJECTIVES: Different sources of prenatal care data were used to examine the association between birth outcomes of HIV-infected women and the Adequacy of Prenatal Care Utilization (APNCU) index. METHODS: Adjusted odds ratios of birth outcomes for 1858 HIV-positive mothers were calculated for APNCU indexes on the basis of birth certificate data or 3 types of physician visits on Medicaid claims. RESULTS: Claims- and birth certificate-based APNCU indexes agreed poorly (kappa < 0.3). Only the broadest claims-based APNCU index had lower adjusted odds ratios for low birthweight (0.64; 95% confidence interval [CI] = 0.49, 0.84) and preterm birth (0.70; 95% CI = 0.54, 0.91). The birth certificate-based index had a reduced adjusted odds ratio (0.73; 95% CI = 0.56, 0.95) only for preterm birth. CONCLUSIONS: The association of birth outcomes and adequacy of prenatal care in this HIV-infected cohort differed significantly depending on the source of prenatal care data.

Relationship between ambulatory care accessibility and hospitalization for persons with advanced HIV disease.

Specific features of ambulatory care, such as accessibility, may influence hospital use for patients with HIV infection. To identify clinic features associated with a lower risk of hospitalization, 6,280 New York state Medicaid enrollees diagnosed with AIDS in 1987-1992 and managed by one of 157 surveyed clinics were studied. The odds of hospitalization in the year before AIDS diagnosis were associated with five clinic features that facilitate the accessibility of care: (1) evening/weekend hours, (2) case manager, (3) appointments within 48 hours, (4) telephone consultation, and (5) whether the clinic handled urgent care. Hospitalization in the year before AIDS diagnosis occurred for 49 percent of patients. Three of the five accessibility features had unadjusted associations with lower hospitalization rates. The adjusted odds of hospitalization were lower for patients in clinics with extended hours (OR = 0.77, 95% CI = 0.63, 0.93) and for patients in clinics with four or more accessibility features compared with those in clinics with less than two features (OR = 0.67; 95% CI = 0.50, 0.89).

The relationship of clinic experience with advanced HIV and survival of women with AIDS.

OBJECTIVE: Hospital and physician experience have been linked to improved outcomes for persons with HIV. Because many HIV-infected patients receive care in clinics, we studied clinic HIV experience and survival for women with AIDS. DESIGN: Retrospective cohort study of women with AIDS whose dominant sources of care were clinics. Clinic HIV experience was estimated as the cumulative number of Medicaid enrollees with advanced HIV who used a particular clinic as their dominant provider up to the year of the patient's AIDS diagnosis: low experience (< 20 patients), medium (20-99 patients), high (> or = 100 patients). Proportional hazards models examined relationships between experience and survival. SETTING: A total of 117 New York State clinics. PATIENTS: A total of 887 New York State Medicaid-enrolled women diagnosed with AIDS in 1989-1992. MAIN OUTCOME MEASURE: Survival after AIDS diagnosis. RESULTS: In later study years (1991-1992), patients in high experience clinics had an approximately 50% reduction in the relative hazard of death (0.53; 95% confidence interval, 0.35-0.82) compared with patients in low experience clinics. Adjusting for demographic and clinical variables, 71% of patients in high experience clinics were alive 21 months after diagnosis compared with 53% in low experience clinics. Experience and survival were not significantly associated in the early study years (1989-1990). CONCLUSIONS: In more recent years, women with AIDS receiving care in high experience clinics survived longer after AIDS diagnosis than those in low experience clinics, providing further evidence of a relationship between provider HIV experience and outcomes.

Repeated emergency department use by HIV-infected persons: effect of clinic accessibility and expertise in HIV care.

Repeated emergency department (ED) visits by HIV-infected persons may signify poor access to care or treatment from inexperienced ambulatory providers. We examined features of 157 clinics following 6820 HIV-infected patients and associations with repeated (> or =2) ED visits by these patients in the year before their first AIDS diagnosis. Patient clinical and health care data came from 1987-1992 New York State (NYS) Medicaid files and clinic data came from interviews of clinic directors. The HIV/AIDS experience of each study patient's clinic was measured as the annual number of Medicaid enrollees newly diagnosed with AIDS who were contemporaneously followed by the patient's clinic. Repeated ED use was observed for 24%. The adjusted odds ratio (AOR) of repeated ED visits was reduced for patients in clinics with a physician on-call (0.77; 95% confidence interval [CI] = 0.65, 0.92), evening or weekend clinic hours (0.77; 95% CI = 0.64, 0.93), or >50 AIDS patients/year in 1987-1988 (0.56; 95% CI = 0.44, 0.71) versus fewer patients in those years. Patients in clinics with more than one feature promoting accessibility or HIV expertise had a greater reduction in their AOR of repeated ED use. HIV-infected patients in clinics with greater accessibility and HIV expertise rely less on the ED for care.

Prevention of vertical HIV transmission with zidovudine: projected impact of HIV testing and prenatal care.

We sought to estimate the impact of maternal HIV testing and prenatal care on the potential to reduce vertical transmission through zidovudine (AZT) use by HIV-infected mothers. We evaluated the prepartum maternal HIV diagnosis rate, prenatal care, disease stage, and vertical transmission rate (from a two-part mixture model) using New York State Medicaid and vital statistics data for HIV-infected mothers and their singletons in 1985-90. We used published data to estimate the effect of AZT on vertical transmission and expert input to define other parameters for the model. Our HIV-infected (N = 1514) had a vertical transmission rate of 27.0%. HIV was diagnosed prepartum for 39.5% of women in 1990. Transmission would have been 22.2% if AZT had been taken only by the subset of women diagnosed prepartum with HIV and receiving prenatal care by 34 weeks gestation (86.7%). Transmission would have dropped to 11.2% if all women had been diagnosed prepartum with HIV and received adequate prenatal care. The observed deficiencies in prenatal care and maternal HIV diagnosis rates in this Medicaid population-based cohort must be addressed to realize the promise of AZT to reduce vertical transmission.

Cigarette smoking and maternal-child HIV transmission.

We investigated the association of cigarette smoking with maternal-child HIV transmission, adjusting for illicit drug use, maternal clinical status, and delivery factors. Vital statistics birth data were linked to the New York State Medicaid HIV/AIDS Research Database for HIV-infected women delivering a liveborn singleton from 1988 through 1990. Follow-up of these children was accomplished by Medicaid data > or = 2 years after birth, and their HIV status was ascertained by a clinically based classification. The adjusted relative risk or hazard (RH) of transmission for maternal factors was determined from Cox models. The overall transmission was 24.5% for the 901 maternal-child pairs. Smokers comprised 40% of women with data on smoking (n = 768); their transmission rate was 31% versus 22% for nonsmokers (p = 0.02). In the entire cohort, the adjusted RH of transmission for smokers was 1.45 (95% confidence interval [CI] 1.07-1.96); among women with advanced HIV, the adjusted RH was even higher (RH = 1.71; 95% CI 1.14-2.58). Users of cocaine (15% of the cohort) or of mixed or unspecified illicit drugs (28%) had higher transmission rates in unadjusted analysis (33%, p = 0.06 and 31%, p = 0.06 respectively); after adjustment for smoking and other maternal factors, neither cocaine (RH = 1.04 (95% CI 0.66-1.63)) nor mixed nor unspecified drug use (RH = 1.13 (95% CI = 0.75-1.70)) was significantly associated with transmission. Our data document an association of cigarette smoking during pregnancy with an increased risk of maternal-child HIV transmission that can be added to the growing list of complications caused by cigarette smoking.

HIV-1 infection in a population-based twin sample.

OBJECTIVE: To examine factors associated with perinatal HIV-1 transmission among twins. METHODS: We identified twins delivered by a population-based cohort of HIV-infected mothers on New York State Medicaid. Tested algorithms were applied to Medicaid files to identify HIV infection in mothers and twins. The HIV transmission rate 3 years after delivery was assessed from Kaplan-Meier curves. Proportional hazards models with adjustment for twin clustering were used to determine the relative hazard (RH) of transmission. RESULTS: In 35 twin pairs, transmission was 20.5%. The risk of transmission was increased significantly for advanced maternal HIV infection (rh = 10.8, 95% confidence interval 2.11, 54.9). We found no association of birth order with twin HIV status. CONCLUSIONS: These data suggest that maternal stage of disease plays a greater role in vertical HIV transmission than birth order. To prevent maternal-child HIV transmission, reducing maternal viral load is likely to have a greater impact than modifying delivery factors.

Clinic services for persons with AIDS. Experience in a high-prevalence state.

OBJECTIVE: To profile characteristics of clinics caring for persons with advanced HIV infection. DESIGN AND SETTING: Survey of clinic directors in New York State. PARTICIPANTS: Newly diagnosed Medicaid-enrolled AIDS patients in New York state in federal fiscal years 1987-1992 (n = 6,184) managed by 62 HIV specialty, 53 hospital-based general medicine/primary care, 36 community-based primary care, and 28 other clinics. MEASUREMENTS AND MAIN RESULTS: Telephone survey about clinic hours, emphasis on HIV, staffing, procedures, and directors' rating of care. Estimates of the number of newly diagnosed, Medicaid-enrolled AIDS patients treated in surveyed clinics were obtained from claims data. We found that community-based clinics were significantly more likely to have longer hours, a physician on call, or to accommodate unscheduled care than were hospital-based general medicine/ primary care or other types of clinics. Compared with HIV specialty clinics, general medicine/primary care clinics were less likely to have HIV-specific care attributes such as a director of HIV care (98% vs 72%), multidisciplinary conferences on HIV care (83% vs 32%), or a standard initial HIV workup (90% vs 70%). Of general medicine/primary care clinics, most (83%) were staffed by residents and fellows compared with only 68% of HIV or 25% of community-based clinics (p < .001). General medicine/primary care clinics were less likely than community-based clinics to perform Pap smears (75% vs 94%) or to have case managers on payroll (21% vs 81%). CONCLUSIONS: In this sample of clinics, hospital-based general medicine/primary care clinics managing the care of Medicaid enrollees with AIDS appeared to have more limited hours and availability of specific services than HIV specialty or community-based clinics.

Prenatal care and birth outcomes of a cohort of HIV-infected women.

Adequate prenatal care has been linked to improved birth outcomes in general populations but has not been assessed in HIV-infected women. We examined longitudinal claims files and vital statistics records for women in the New York State Medicaid HIV/AIDS data base delivering a singleton from 1985 through 1990. Adequacy of the self-reported number of prenatal visits was assessed by the Kessner index. In logistics models, we estimated the association of prenatal care, illicit drug use, and other maternal characteristics with three outcomes; low birth weight, preterm birth, and small-for-gestational-age. Of 2,254 singletons delivered by this HIV-infected cohort, 28% were low birth weight, 23% were preterm birth, and 20% were small for gestational age. Two-thirds had inadequate prenatal care. Non-drug users had 57 and 26% lower adjusted odds of low birth weight and preterm delivery than drug users. The adjusted odds of low birth weight and preterm birth for women with an adequate number of prenatal visits were, respectively, 48 and 21% lower than for women with inadequate care. Adequate prenatal care was also associated with a 43% reduction in the odds of small-for-gestational-age. An adequate number of prenatal visits by women in this HIV cohort was associated with a significant reduction in all three adverse birth outcomes, but most had inadequate prenatal care. These data support strengthening efforts to bring pregnant, HIV-infected women into care.

Health care of children and adults with acquired immunodeficiency syndrome. A population-based analysis.

OBJECTIVES: To compare the use of medical services by pediatric and adult patients with acquired immunodeficiency syndrome (AIDS) in the 6 months before and after the diagnosis of AIDS when demand for care is often high and to study the influence of human immunodeficiency virus specialty care on survival of pediatric patients. DESIGN: Retrospective analysis of Medicaid files. SETTING: New York State Medicaid Program. PATIENTS: A cohort identified as having AIDS from 1985 through 1990 and enrolled on Medicaid from birth or 1 year or more before diagnosis. Because of differing prognoses, 3 groups were studied by age at the time that AIDS was diagnosed: infants younger than 6 months, children aged 6 months to 12 years, and adults aged 13 to 60 years. MAIN OUTCOME MEASURES: Frequencies of any service use and, among users, monthly rates of services. From Cox proportional hazards models, the adjusted hazard of death for human immunodeficiency virus specialty ambulatory care. RESULTS: Nearly all infants (n = 122) were hospitalized before and after the diagnosis of AIDS was made--the most of all groups. After diagnosis, only 81% of older children (n = 612) were hospitalized vs 93% of infants and 90% of adults (n = 5602). Hospitalized children had a median of only 3.3 inpatient days per month vs 12.3 and 7.8 inpatient days for infants and adults, respectively. Of older children, 45% used the emergency department vs 33% of adults. Human immunodeficiency virus specialty care for infants and children was associated with a 40% lower risk of death after the diagnosis of AIDS. CONCLUSIONS: In this AIDS cohort, infants had the greatest use of inpatient care, and older children used the emergency department more than adults. The finding of improved survival for infants and children with human immunodeficiency virus specialty care warrants further study in more recent years.

Patterns of ambulatory care for AIDS patients, and association with emergency room use.

OBJECTIVE: We examined the association of patterns of ambulatory care for AIDS patients with any use of the emergency room (ER) and the monthly rate of ER visits in the six months after AIDS diagnosis. DATA SOURCES/STUDY SETTING: The study population was obtained from the New York State Medicaid HIV/AIDS Research Data Base and includes patients diagnosed with AIDS from 1983 to 1990. DATA COLLECTION/EXTRACTION METHODS: To examine patterns of care and ER use not leading to hospitalization, we studied patients who survived at least six months after their first AIDS-defining diagnosis. The data base included person level information on visits to different provider sites and patient demographic and clinical characteristics. STUDY DESIGN: We defined the dominant provider as the site delivering the majority of ambulatory care for patients with a minimum of four ambulatory visits in the six months after AIDS diagnosis. Dominant providers were classified by specialty and setting: generalist physician; general medicine clinic; AIDS specialty clinic; and other specialty clinic or physician (e.g., cardiology). Patients without a dominant provider were grouped into those with four or more visits and those with fewer than four visits. Regression analysis was used to estimate relationships between ER use and patterns of ambulatory care and patient demographic and severity of illness characteristics. PRINCIPAL RESULTS: The study population included 9,155 AIDS patients aged 13 to 60 years at diagnosis, continuously Medicaid-enrolled, and surviving at least six months after AIDS diagnosis. Among those with four or more visits (56 percent), over 70 percent had a dominant provider. Overall, 39 percent of the study population visited the ER while, in the group with four or more visits, 53 percent of those without a dominant provider had an ER visit. Patients without a dominant provider were estimated to have 32 percent higher odds of ER use than patients with a dominant provider. Among patients with a dominant provider, patients with a generalist or primary care clinic dominant site of care were estimated respectively to have 18 percent and 23 percent lower odds than patients with an AIDS specialty clinic as the dominant site of care. Drug users had higher odds of ER use, as did women. CONCLUSIONS: In this Medicaid AIDS population, a dominant provider delivering the majority of a patient's care was associated with less use of the ER by the patient. Among patients with a dominant provider, ER use was lowest for those with a primary care provider. Further examination of the type and availability of ambulatory services in AIDS specialty clinics and primary care settings, as well as more detailed information on patient characteristics, may reveal reasons for these patterns of ER use.

Patterns of Medicaid expenditures after AIDS diagnosis.

This article examines average monthly Medicaid expenditures after diagnosis of acquired immunodeficiency syndrome (AIDS) for the diagnosis, mid-illness, and death intervals, as well as Kaplan-Meier estimates of expenditures from AIDS diagnosis to death. A clinical severity measure (the Severity Index for Adults with AIDS [SIAA]) designed to be predictive of patient survival was applied to a population of continuously enrolled New York State Medicaid patients who survived at least 6 months after being diagnosed with AIDS. Our findings suggest that groups of more seriously ill patients who appear to have more intense demand for health care services, especially over the diagnosis and mid-illness intervals, can be identified using the SIAA.

Duration of Medicaid AIDS hospitalizations--variation by season, stage, and year.

Using New York State Medicaid data from 1984 to 1987, we analyzed hospital length-of-stay patterns for acquired immunodeficiency syndrome (AIDS) patients. We found an overall decline in monthly average length of stay, with seasonal fluctuations producing longer stays in the fall and winter months. These findings suggest that hospital utilization for AIDS patients is changing over time and may vary by season.

The epidemiology of AIDS in the New York and California Medicaid programs.

An epidemiological analysis of the impact of AIDS on the New York and California Medicaid programs was conducted for 1983-1986. The epidemic affected the New York and California Medicaid programs in several similar ways. The total number of cases grew rapidly over the study time period. In both states, the epidemic was mostly confined to the young adult (21-44 years) age group. Cases were geographically concentrated and highly localized even within counties, but evidence of geographic dispersion to counties outside of the urban centers was also evident. Some dramatic differences were also found between California and New York. Patients with claims histories of drug use were far more likely to be found in the New York population and the proportion of other adult males (our proxy for the homosexual risk group) was higher in California. A much higher proportion of New York's population was female (30 vs. 5%). New York also had many more pediatric cases. Most importantly, New York's raw number of cases was substantially higher than California, with approximately three times as many cases during the time period (1983-1986). There is also substantial evidence that transmission of the disease to heterosexual partners of drug users places heterosexual urban minorities at grave risk of contracting the disease through interaction with infected persons.

Medicaid eligibility patterns for persons with AIDS in California and New York, 1982-1987.

An analysis of Medicaid eligibility patterns for persons with AIDS (PWAs) was conducted, based on the longitudinal Medicaid eligibility histories of 1,314 AIDS decedents in California and 6,273 AIDS decedents in New York between 1982 and 1987. The study analyzed what eligibility groups or categories and which financial standards PWAs were using to qualify for Medicaid. States have many options with regard to the categories of people they cover under Medicaid and where they set their financial thresholds. The study findings are useful in showing how these policy decisions affect PWAs. A major conclusion of the study is the importance of medically needy coverage for PWAs. Medically needy coverage, which is optional to states, opens up Medicaid to persons of any income level, assuming their medical expenses are high enough. The study also found that PWAs who qualify only through the medically needy provisions have much shorter enrollment and lower lifetime Medicaid expenditures than other PWAs on Medicaid. Presumably, most medically needy only enrollees have other sources of health care coverage in the early stages of the illness. Study data also suggested significant administrative obstacles for PWAs in dealing with the Medicaid eligibility process. Finally, an unexpected study result was that all states may not be aggressively utilizing federal Medicaid financing options for covering the medical assistance expenditures for a significant proportion of the low-income AIDS population.

Lifetime Medicaid service utilization and expenditures for AIDS in New York and California.

Several important gaps exists in information on the health care resources used by people with AIDS, including patterns of outpatient care, differences between populations at risk of the disease, and services paid for by Medicaid. To address the shortage of information in these areas, this study examined average Medicaid expenditures and service use for the time period a person has AIDS. The study population was Medicaid enrollees with AIDS in New York and California who died between October 1985 and September 1986. The study focused on the differences between the two states and between four groups that were proxies for at-risk populations: children, women, drug-using men, and non-drug-using men. Mean lifetime Medicaid expenditures were about $30,000 in New York and $20,000 in California. Inpatient use was higher and outpatient service use was lower in New York than in California after controlling for risk group, diagnosis, and Medicaid eligibility group (a proxy for income level). In California, women had higher expenditures and inpatient use than men. In New York, women and drug-using men had higher expenditures and use of inpatient and outpatient services (except home health care) than the non-drug-using men. Children in New York had higher expenditures and hospital use than adults but similar outpatient service use. Multivariate analyses suggest that differences between risk groups were largely attributable to differences in diagnosis and income level (as measured by Medicaid eligibility group).