Application of Intersection-Union Tests for Identifying Metabolite Biomarkers for Diagnosis and Prognosis

• Activity Number: 360
• Type: Contributed
• Date/Time: Tuesday, August 3, 2010 : 10:30 AM to 12:20 PM
• Sponsor: Biometrics Section
• Author(s): Kyoungmi Kim*+ and Stanislav O. Zakharkin
• Companies: University of California, Davis and Cadbury North America
• Keywords: Intersection-union test ; metabolomics analysis ; biomarker ; diagnosis ; prognosis

Abstract

Polycystic kidney disease (PKD) consistently reduces renal filtration function over time. It is likely that metabolic changes may occur early in the course of disease prior to changes in renal function. Metabolites with lower levels in PKD patients than in healthy subjects are expected to be best biomarkers for use in diagnosis and prognosis. We are working on identification of metabolites whose levels do not change significantly over time (i.e., constancy) and those are continuously decreased as the disease progresses (deceleration). These tests entail to consider different time spans of disease progression and require testing several hypotheses related to trends over time. GC-TOF mass spectrometry-based metabolomic analysis was performed on urine samples taken at several stages of PKD disease. We applied intersection-union tests for detecting changes in metabolite levels over time.