Background: Hyperinsulinemia has been associated with hepatic fat deposition and ensuing insulin resistance. It is unknown if treatment with exogenous insulin in patients with type 2 diabetes, who are most prone to hepatic fat accumulation, would promote the occurrence or worsening of nonalcoholic fatty liver disease.
Methods: Patients with treatment-naive type 2 diabetes (N = 16) were treated with insulin and metformin for a 3-month lead-in period, then assigned triple oral therapy (metformin, glyburide, and pioglitazone) or continued treatment with insulin and metformin. Hepatic triglyceride content (HTC)-measured by magnetic resonance spectroscopy, serum lipids, glucose, liver function tests, and inflammatory and thrombotic biomarkers were followed for a median of 31 months.
Results: The 45% decline in HTC during the lead-in period persisted through the follow-up period with no difference between treatment groups at the end of the study (5.26 ± 4.21% in the triple oral therapy vs 7.47 ± 7.40% for insulin/metformin), whereas glycemic control was comparable.
Conclusions: Improvements in HTC with initial insulin/metformin therapy persisted through the median 31-month follow-up period regardless of the treatment. More importantly, insulin-based treatment did not appear to promote or worsen nonalcoholic fatty liver disease.