DEVELOPMENT AND EVALUATION OF A COMPUTER-BASED SYSTEM FOR DIETARY-MANAGEMENT OF HYPERLIPIDEMIA

Objective To describe the development of a computer-based system for d ietary management of hyperlipidemia and to evaluate its efficacy for l owering plasma cholesterol level. Design Using a stepwise approach. we developed and tested a three-part self-management system in five cons ecutive clinical studies. Each study assessed plasma cholesterol level s before and after dietary intervention using the system. These studie s enabled progressive refinement of (a) a food frequency questionnaire used to assess food intake in the preceding month; Cb) computer-gener ated progress reports, based on questionnaire responses; offering diet ary change subgoals and strategies for change and (c) a dietary work-b ook providing detailed information on how to achieve goals. Subjects/s etting Persons with hyperlipidemia (n=814) were enrolled from worksite and clinical settings in the San Francisco Bay area of California. Th e attrition rate after randomization nas 5%. Intervention Elements of the dietary intervention evolved in response to the results of five cl inical studies. Ln each study, patients underwent a form of baseline a ssessment of dietary intake followed by counseling/instruction by vari ous means. Follow-up dietary assessments mere provided at specific int ervals to facilitate subjects' progress toward their dietary goals. A dietary workbook provided the detailed instruction required to impleme nt the recommendations contained in the periodic progress reports. Sta tistical analyses performed Changes in plasma cholesterol level were m easured by paired and unpaired t tests. The relationship between the r eported reduction in dietary fat and cholesterol level assessed by foo d frequency questionnaires and the directly measured change in plasma cholesterol level was measured by multiple linear regression. Results The three major elements of the final computerized system (food freque ncy questionnaires, computer-generated progress reports, and dietary w orkbook) were developed and refined in the course of the five clinical studies. Reductions in total plasma cholesterol level uf 5.0% to 6.5% achieved by participants in all five studies were consistent with sel f-reported reductions in intake of dietary saturated fat and cholester ol. Therefore, the computerized self-management system appears to be a n effective tool for reducing plasma cholesterol levels. Applications/ conclusions A computer-based system for dietary self-management of hyp erlipidemia, implemented by mail, was effective in short-term studies. This self-management system can potentially provide health-promoting services to large numbers of people at low cost.