Screening to prevent renal failure in insulin dependent diabetic patients: An economic evaluation

Objective-To examine the conditions necessary to make screening for microalbuminuria in patients with insulin dependent diabetes mellitus cost effective. Design-This economic evaluation compared two strategies designed to prevent the development of end stage renal disease in patients with insulin dependent diabetes with disease for five years. Strategy A, screening for microalbuminuria as currently recommended, was compared with strategy B, a protocol in which patients were screened for hypertension and macroproteinuria. Intervention-Patients identified in both strategies were treated with an angiotensin converting enzyme inhibitor. Setting-Computer simulation. Main outcome measures-Strategy costs and quality adjusted life years (QALYs). Results-The model predicted that strategy A would produce an additional 0 . 00967 QALYs at a present value cost of $261.53 (1990 US$) per patient (or an incremental cost/QALY of $27041.69) over strategy B. The incremental cost/QALY for strategy A over B was sensitive to several variables. If the positive predictive value of screening for microalbuminuria (impact of false label and unnecessary treatment) is <0 . 72, the effect of treatment to delay progression from microalbuminuria to macroproteinuria is <1 . 6 years, the cumulative incidence of diabetic nephropathy falls to < 20%, or > 64% of patients demonstrate hypertension at the onset of microalbuminuria, then the incremental costs/QALY will exceed $75 000. Conclusions-Whether microalbuminuria surveillance in this population is cost effective requires more information. Being aware of the costs, recommendation pitfalls, and gaps in our knowledge should help focus our efforts to provide cost effective care to this population.