Liver function tests: what is the risk?

Five laboratory assays are commonly called liver function tests (LFTs), although these tests are neither specific to the liver nor true measures of liver function. As a result, alanine aminotransferase (ALT or SGPT), aspartate aminotransferase (AST or SGOT), gamma-glutamyltransferase (GGT), alkaline phosphatase (ALP) and bilirubin have proven problematic for clinicians and risk selection professionals alike. Further, underwriters and insurance medical directors find these tests difficult to assess because of the lack of data directly relating LFT elevations to mortality outcome. Nonetheless, the tests are frequently encountered, so a strategy for evaluating abnormal results is critical to ensure accurate and fair pricing. This paper reviews basic information on LFTs, available mortality data and the application of this knowledge to the underwriting process.