Clinical assessment of HIV-associated lipodystrophy in an ambulatory population.

OBJECTIVE: To identify clinical factors associated with prevalence of fat atrophy (lipoatrophy) and fat accumulation (lipoaccumulation) in HIV-1 infected patients. DESIGN: Evaluation of HIV-1 infected patients seen for routine care between 1 October and 31 December 1998 in the eight HIV Outpatient Study (HOPS) clinics. SETTING: Eight clinics specializing in the care of HIV-1 infected patients. PATIENTS: A total of 1077 patients were evaluated for signs of fat maldistribution. INTERVENTIONS: A standardized set of questions and specific clinical signs were assessed. Demographic, clinical and pharmacological data for each patient were also included in the analysis. MAIN OUTCOME MEASURES: Demographic, immunologic, virologic, clinical, laboratory, and drug treatment factors were assessed in stratified and multivariate analyses for their relationship to the presence and severity of fat accumulation and atrophy. RESULTS: Independent factors for moderate/severe lipoatrophy for 171 patients were increasing age, any use of stavudine, use of indinavir for longer than 2 years, body mass index (BMI) loss, and measures of duration and severity of HIV disease. Independent risk factors for moderate/severe fat accumulation for 104 patients were increasing age, BMI gain, measures of amount and duration of immune recovery, and duration of antiretroviral therapy (ART). The number of non-drug risk factors substantially increased the likelihood of lipoatrophy. If non-drug risk factors were absent, lipoatrophy was unusual regardless of the duration of drug use. CONCLUSIONS: HIV-associated lipodystrophy is associated with several host, disease, and drug factors. While prevalence of lipoatrophy increased with the use of stavudine and indinavir, and lipoaccumulation was associated with duration of ART, other non-drug factors were strongly associated with both fat atrophy and accumulation.

The incidence of Kawasaki syndrome in West Coast health maintenance organizations.

BACKGROUND: Kawasaki syndrome (KS) causes an acute vasculitis of unknown etiology. It is a leading cause of acquired heart disease of children in Japan and the United States. METHODS: We examined the incidence of KS in a well-defined population group of children < or =6 years of age, using data collected through the Vaccine Safety Datalink (VSD) project. The VSD database contains information on >1 million children enrolled in four West Coast health maintenance organizations (HMOs). RESULTS: During 1993 through 1996 a total of 234 physician-diagnosed KS patients were reported in the 4 HMOs; 152 (65.0%) were boys and 195 (83.3%) were <5 years of age. The incidence of KS among children <5 years of age in the HMOs ranged from 9.0 to 19.1 per 100,000 person years. KS incidence was higher among boys in 3 of the sites. In the 2 sites with the highest number of KS patients, a seasonal occurrence of KS in winter and early spring was observed. Overall 226 (96.6%) of the KS patients were reported to have been hospitalized; hospitalization rates for children <5 years of age ranged from 9.0 to 16.8 per 100,000 person years. CONCLUSIONS: The incidence of KS in the HMOs was similar to that reported in other population-based studies in the United States and higher than estimates for Australia and several European countries.

Ukraine, 1992: first assessment of diphtheria vaccine effectiveness during the recent resurgence of diphtheria in the Former Soviet Union.

A case-control study in Ukraine provided the first data on the field effectiveness of Russian-produced vaccine during the 1990 diphtheria resurgence in the former Soviet Union. For each of 262 diphtheria cases <15 years of age who were reported from January through October 1992, 2 controls, matched by age and clinic, were selected. The effectiveness of three doses of diphtheria vaccine was 98.2% (95% confidence interval: 90.3-99.9). Among controls, 84% had received three or more vaccinations by 2 years of age. These results suggest that the following five hypothesized causes of the outbreak appeared unlikely: appearance of a new "mutant" diphtheria strain, low potency of the Russian-produced diphtheria vaccine, inadequate cold chain, poor host immunogenicity due to radiation exposure from Chernobyl, and low routine childhood vaccination coverage. It is concluded that initial priority for scarce resources for controlling this outbreak should be placed on vaccination of persons susceptible to diphtheria (e.g., adults) rather than revaccination of children.

Epidemiology of diarrheal disease among children enrolled in four West Coast health maintenance organizations. Vaccine Safety Datalink Team.

BACKGROUND: We used information from the Vaccine Safety Datalink (VSD) about approximately 1 million children enrolled in four health maintenance organizations to assess the morbidity from diarrhea and estimate the disease burden of rotavirus. METHODS: We examined trends of diarrhea-associated hospitalizations and emergency room (ER) visits among VSD children ages 1 month through 4 years during October, 1992, through September, 1994 (two rotavirus seasons) and estimated the morbidity from rotavirus on the basis of characteristic patterns of age and seasonality. RESULTS: Overall diarrhea was associated with 6.3% of hospitalizations and 4% of ER visits. During a child's first 5 years of life, we estimated that 1 in 57 was hospitalized and 1 in 21 required an ER visit because of diarrhea. Each year the number of diarrhea-associated hospitalizations and ER visits was greatest in winter among children ages 4 to 23 months and peaked in November in California and during February in Oregon and Washington. The winter seasonality of diarrhea-associated hospitalizations reflected the trends for diarrhea of presumed noninfectious and viral etiologies, which together accounted for most (92.9%) hospitalizations. CONCLUSIONS: Diarrhea is an important cause of morbidity among VSD children. The epidemiologic patterns of diarrhea-associated hospitalizations and ER visits resembled those reported previously for rotavirus diarrhea, suggesting that rotavirus may be a major contributor to the overall morbidity from diarrhea. Enhanced surveillance by screening for rotavirus in a sample of children with diarrhea will permit a more accurate assessment of the disease burden of this pathogen and the cost effectiveness of a rotavirus immunization program.

Vaccine Safety Datalink project: a new tool for improving vaccine safety monitoring in the United States. The Vaccine Safety Datalink Team.

OBJECTIVE: To fill the large "gaps and limitations" in current scientific knowledge of rare vaccine adverse events identified in recent reviews of the Institute of Medicine. METHODS: Computerized information on immunization, medical outcomes, and potential confounders on more than 500 000 children 0 to 6 years of age is linked annually at several health maintenance organizations to create a large cohort for multiple epidemiologic studies of vaccine safety. RESULTS: Analysis of 3 years of follow-up data shows that 549 488 doses of diphtheria-tetanus-pertussis (DTP) and 310 618 doses of measles-mumps-rubella (MMR) vaccines have been administered to children in the study cohort. Analyses for associations between vaccines and 34 medical outcomes are underway. Screening of automated data shows that seizures are associated with receipt of DTP on the same day (relative risk [RR], 2.1; 95% confidence interval [CI], 1.1 to 4.0) and 8 to 14 days after receipt of MMR (RR, 3.0; 95% CI, 2.1 to 4.2). The diversity of vaccination exposures in this large cohort permits us to show that an apparent association of seizures 8 to 14 days after Haemophilus influenzae type b vaccine (RR, 1.6; 95% CI, 1.2 to 2.1) was attributable to confounding by simultaneous MMR vaccination; the association disappears with appropriate adjustment (RR, 1.0; 95% CI, 0.7 to 1.4). CONCLUSION: Preliminary design, data collection, and analytic capability of the Vaccine Safety Datalink project has been validated by replication of previous known associations between seizures and DTP and MMR vaccines. The diversity in vaccine administration schedules permits potential disentangling of effects of simultaneous and combined vaccinations. The project provides a model of public health-managed care collaborations in addition to an excellent infrastructure for safety and other studies of vaccines.

Influenza vaccination programs for elderly persons: cost-effectiveness in a health maintenance organization.

OBJECTIVE: To estimate the cost-effectiveness and net medical care costs of programs for annual influenza vaccinations for the elderly in a health maintenance organization (HMO). DESIGN: Population-based, case-control study. SETTING: The Northwest Region of Kaiser Permanente, a prepaid group practice HMO in Portland, Oregon. PARTICIPANTS: Kaiser Permanente members 65 years of age and older who had at least 1 month of HMO eligibility during any of nine influenza seasons in the 1980s. MEASUREMENTS: The HMO's costs for providing medical care and conducting vaccination programs were estimated using accounting data. RESULTS: 32% of high-risk elderly persons and 22% of non-high-risk elderly persons received influenza vaccinations. Aggregate vaccine effectiveness in preventing pneumonia and influenza hospitalizations was 30% (95% CI, 17% to 42%) for high-risk and 40% (CI, 1% to 64%) for non-high-risk elderly persons. The net savings to the HMO per vaccination was $6.11 for high-risk elderly persons and $1.10 for all elderly persons. The HMO incurred a net cost of $4.82 per vaccination for non-high-risk elderly persons. CONCLUSIONS: Influenza vaccination rates in this HMO were relatively low for high-risk elderly persons. The medical care costs saved by preventing pneumonia and influenza through vaccination of high-risk elderly persons provide a compelling rationale to increase compliance with recommendations for annual influenza vaccination. Indirect benefits, such as prevention of suffering, incapacity, and lost wages, are likely to compensate for the small net cost of vaccinating non-high-risk elderly persons.