Background: South Asians have a high risk to develop type 2 diabetes, which may be related to substantial ectopic fat deposition. Since glucagon-like peptide-1 analogues can reduce ectopic fat accumulation, the aim of the present study was to assess the effect of treatment with liraglutide for 26 weeks on ectopic fat deposition and HbA1c in South Asian patients with type 2 diabetes.
Methods: In a placebo-controlled trial, 47 South Asian patients with type 2 diabetes were randomly assigned to treatment with liraglutide (1.8 mg/day) or placebo added to standard care. At baseline and after 26 weeks of treatment we assessed abdominal subcutaneous, visceral, epicardial and paracardial adipose tissue volume using MRI. Furthermore, myocardial and hepatic triglyceride content were examined with proton magnetic resonance spectroscopy.
Results: In the intention-to-treat analysis, liraglutide decreased body weight compared to placebo (- 3.9 ± 3.6 kg vs - 0.6 ± 2.2 kg; mean change from baseline (liraglutide vs placebo): - 3.5 kg; 95% CI [- 5.3, - 1.8]) without significant effects on the different adipose tissue compartments. HbA1c was decreased in both groups without between group differences. In the per-protocol analysis, liraglutide did decrease visceral adipose tissue volume compared to placebo (- 23 ± 27 cm2 vs - 2 ± 17 cm2; mean change from baseline (liraglutide vs placebo): - 17 cm2; 95% CI [- 32, - 3]). Furthermore, HbA1c was decreased by liraglutide compared to placebo (- 1.0 ± 0.8% (- 10.5 ± 9.1 mmol/mol)) vs (- 0.6 ± 0.8% (- 6.1 ± 8.8 mmol/mol)), with a between group difference (mean change from baseline (liraglutide vs placebo): - 0.6% (- 6.5 mmol/mol); 95% CI [- 1.1, - 0.1 (- 11.5, - 1.5)]). Interestingly, the decrease of visceral adipose tissue volume was associated with the reduction of HbA1c (β: 0.165 mmol/mol (0.015%) per 1 cm2 decrease of visceral adipose tissue volume; 95% CI [0.062, 0.267 (0.006, 0.024%)]).
Conclusions: While the intention-to-treat analysis did not show effects of liraglutide on ectopic fat and HbA1c, per-protocol analysis showed that liraglutide decreases visceral adipose tissue volume, which was associated with improved glycaemic control in South Asians. Trial registration NCT02660047 (clinicaltrials.gov). Registered 21 January 2016.
Keywords: Diabetes mellitus type 2; Ectopic fat; GLP-1 analogue; Liraglutide; Magnetic resonance imaging; Magnetic resonance spectroscopy; Randomised clinical trial; South Asian.