Insulin sensitizers in treatment of nonalcoholic fatty liver disease: Systematic review.
OBJECTIVE
To summarize the evidence available for the clinical effectiveness of insulin sensitizers in the treatment of nonalcoholic fatty liver disease (NAFLD) systematically.


METHODS
Relevant articles were located using computer-assisted searches of Medline (1966-March 2006), EMBASE (1988-March 2006), CINAHL (1982-March 2003), Educational Resource Information Center (1966-March 2006), Library, Information Science and Technology Abstracts (1967-March 2006), Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (1994-2006), dissertations in ProQuest and FirstSearch databases. Manual searches were made in the abstracts from meetings of the American Gastroenterological Association (1999-2006), and the American Association for the Study of Liver Diseases (2003-2005). Studies were retrieved using the following selection criteria: (1) clinical trials using insulin sensitizers in subjects with NAFLD, (2) adult patients, (3) published as full manuscripts or abstracts, and (4) English, Spanish, German, and French languages only. Data were abstracted independently by two reviewers following standardized procedures. A face-to-face comparison of data was conducted to ensure the completeness and reliability of the abstraction process.


RESULTS
Nine studies were included, six using metformin and three using thiazolidinediones. Only two studies were placebo-controlled trials. The median sample size for all studies was 18 subjects. In the placebo-controlled trials, metformin improved insulin resistance markers and liver function tests, but not histological scores. In the single-arm trials, metformin and thiazolidinediones improved insulin resistance markers and liver function tests, and beneficial histological changes were reported. There is limited high-quality information available from which to draw categorical conclusions about the clinical use of insulin sensitizers in NAFLD.


CONCLUSIONS
Current information indicates that the use of insulin sensitizers in NAFLD improves insulin resistance and liver function. Histological changes must be corroborated in randomized controlled trials.
Chavez-Tapia
Norberto-C
NC
Department of Gastroenterology, Instituto Nacional de Ciencias Médicas y Nutrición Zalvador Zubirán, Mexico City, Mexico. khavez@hotmail.com
Barrientos-Gutierrez
Tonatiuh
T
Tellez-Avila
Felix-I
FI
Sanchez-Avila
Francisco
F
Montano-Reyes
Maria-Antonieta
MA
Uribe
Misael
M
D018849:Controlled Clinical Trials as Topic; D050528:Diet, Carbohydrate-Restricted; D005234:Fatty Liver / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000502:physiology*; D007333:Insulin Resistance / Q000502:physiology; D008099:Liver / Q000503:physiopathology; D008687:Metformin / Q000627:therapeutic use; D045162:Thiazolidinediones / Q000627:therapeutic use
D007004:Hypoglycemic Agents; D007328:Insulin; D045162:Thiazolidinediones; D008687:Metformin