Summary

A Clinical Practice Improvement study was conducted at six HMOs throughout the US to determine the effect of HMO organizational strategies on outpatient visits, hospital admissions, and prescriptions on patients with at least one of five diseases (arthritis, asthma, epigastric pain/ulcer, hypertension, and otitis media).  Data were collected from 13,000 patients at every encounter for one year.  Results show that for the five study diseases, physician continuity was associated with reduced healthcare utilization.  The findings lend credence to the hypothesis that physician continuity, combined with chart and site continuity, is associated with reduced health care costs.

Primary Objective

1. Examine the association between the degree of health care provider continuity and health care utilization and costs of HMO patients.

Methods

1. Longitudinal, prospective data on 12,997 patients with arthritis, asthma, epigastric pain/peptic ulcer disease, hypertension, or otitis media were collected at each of 6 HMOs.

2. Outcome variables included the number of prescriptions for the target disease and the cost, total number of prescriptions and the cost, the number of outpatient visits, and the number of hospital admissions.

3. Disease-specific severity of illness, type of visit, and provider information were obtained at each encounter.

4. HMO profit status, visit copay, gatekeeper strictness, formulary limitations, use of multisource (generic) drugs, gender, number of months in the study, age, and severity of illness were controlled in the analyses.

Results

1. There were 12,997 patients followed for more than 99,000 outpatient visits, 1,000 hospitalizations, and more than 240,000 prescriptions.

2. Increasing the number of primary or specialty care providers a patient encountered during the study was associated with increased utilization and costs when HMO and patient characteristics were controlled.

3. The number of specialty care providers also increased as the number of primary care providers increased.

4. The incremental increase in pharmacy costs per patient per year with each additional provider ranged between $19 in subjects with otitis media to $58 in subjects with hypertension.
   

Impact

Continuity of care was associated with a reduction in resource utilization and costs.  As health care delivery systems are designed, care continuity should be promoted (Amer. J. Managed Care, 5:6, June 1999:727-734).