Nonalcoholic fatty liver disease (NAFLD) in the Veterans Administration population: development and validation of an algorithm for NAFLD using automated data. Issue 8 (26th August 2014)

• Record Type: Journal Article
• Authors: Husain, N.; Blais, P.; Kramer, J.; Kowalkowski, M.; Richardson, P.; El‐Serag, H. B.; Kanwal, F.
• Is Part Of: Alimentary pharmacology & therapeutics. Volume 40:Issue 8(2014)
• Page Start: 949
• Page End: 954
• Publication Date: 2014-08-26
• Subjects: Digestive organs -- Diseases -- Treatment -- Periodicals; Digestive organs -- Effect of drugs on -- Periodicals; Gastrointestinal system -- Diseases -- Treatment -- Periodicals; Gastrointestinal system -- Effect of drugs on -- Periodicals; 615.73
• DOI: 10.1111/apt.12923
• Languages: English
• ISSNs: 0269-2813

Abstract

<abstract abstract-type="main" id="apt12923-abs-0001"> <title>Summary</title> <sec id="apt12923-sec-0001" sec-type="section"> <title>Background</title> <p>In practice, nonalcoholic fatty liver disease (NAFLD) is diagnosed based on elevated liver enzymes and confirmatory liver biopsy or abdominal imaging. Neither method is feasible in identifying individuals with NAFLD in a large‐scale healthcare system.</p> </sec> <sec id="apt12923-sec-0002" sec-type="section"> <title>Aim</title> <p>To develop and validate an algorithm to identify patients with NAFLD using automated data.</p> </sec> <sec id="apt12923-sec-0003" sec-type="section"> <title>Methods</title> <p>Using the Veterans Administration Corporate Data Warehouse, we identified patients who had persistent ALT elevation (≥2 values ≥40 IU/mL ≥6 months apart) and did not have evidence of hepatitis B, hepatitis C or excessive alcohol use. We conducted a structured chart review of 450 patients classified as NAFLD and 150 patients who were classified as non‐NAFLD by the database algorithm, and subsequently refined the database algorithm.</p> </sec> <sec id="apt12923-sec-0004" sec-type="section"> <title>Results</title> <p>The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) for the initial database definition of NAFLD were 78.4% (95% CI: 70.0–86.8%), 74.5% (95% CI: 68.1–80.9%), 64.1% (95% CI: 56.4–71.7%) and 85.6% (95% CI: 79.4–91.8%), respectively. Reclassifying patients as having NAFLD if they had two elevated ALTs that were at least 6 months apart but within 2 years of each other, increased the specificity and PPV of the algorithm to 92.4% (95% CI: 88.8–96.0%) and 80.8% (95% CI: 72.5–89.0%), respectively. However, the sensitivity and NPV decreased to 55.0% (95% CI: 46.1–63.9%) and 78.0% (95% CI: 72.1–83.8%), respectively.</p> </sec> <sec id="apt12923-sec-0005" sec-type="section"> <title>Conclusions</title> <p>Predictive algorithms using automated data can be used to identify patients with NAFLD, determine prevalence of NAFLD at the system‐wide level, and may help select a target population for future clinical studies in veterans with NAFLD.</p> </sec> </abstract>