Effects of skim milk powder enriched with glycomacropeptide and G600 milk fat extract on frequency of gout flares: a proof-of-concept randomised controlled trial
- Nicola Dalbeth1,
- Ruth Ames1,
- Greg D Gamble1,
- Anne Horne1,
- Sumwai Wong1,
- Barbara Kuhn-Sherlock2,
- Alastair MacGibbon2,
- Fiona M McQueen3,
- Ian R Reid1,
- Kate Palmano2
- 1Bone and Joint Research Group, Department of Medicine, University of Auckland, Auckland, New Zealand
- 2Fonterra Research Centre, Dairy Farm Road, Palmerston North, New Zealand
- 3Department of Molecular Medicine, University of Auckland, Auckland, New Zealand
- Correspondence to Associate Professor Nicola Dalbeth, Department of Medicine, Faculty of Medical and Health Sciences, University of Auckland, 85 Park Rd, Grafton, Auckland, New Zealand;
Contributors Nicola Dalbeth (the guarantor) accepts full responsibility for the work and the conduct of the study, had access to the data and controlled the decision to publish. Design of study protocol: ND, RA, GG, AH, BKS, AM, FM, IR, KP. Acquisition of study data: RA, AH, SW, KP. Data analysis: GG, BKS. Interpretation of data: ND, FM, IR, KP. Drafting of manuscript: all authors. Final approval of manuscript: all authors.
- Received 10 May 2011
- Accepted 29 November 2011
- Published Online First 23 January 2012
Objectives Previous laboratory studies have identified two dairy fractions, glycomacropeptide (GMP) and G600 milk fat extract (G600), with anti-inflammatory effects in models of acute gout. The aim of this proof-of-concept clinical trial was to test the hypothesis that daily intake of skim milk powder (SMP) enriched with GMP and G600 can prevent gout flares.
Methods This was a 3-month randomised double-blind controlled trial of milk products for prevention of gout flares. One hundred and twenty patients with recurrent gout flares were randomised to one of three arms: lactose powder control, SMP control and SMP enriched with GMP and G600 (SMP/GMP/G600). The primary end point was change in the frequency of gout flares using a daily flare diary measured monthly for 3 months.
Results The frequency of gout flares reduced in all three groups over the 3-month study period compared with baseline. Over the 3-month study period there was a significantly greater reduction in gout flares in the SMP/GMP/G600 group (analysis of covariance pgroup=0.031, Tukey post hoc test compared with lactose control, p=0.044). Following treatment with SMP/GMP/G600 over the 3-month period, greater improvements were also observed in pain and fractional excretion of uric acid, with trends to greater improvement in tender joint count. Similar adverse event rates and discontinuation rates were observed between the three groups.
Conclusions This is the first reported controlled trial of dietary intervention in patients with gout, and suggests that SMP enriched with GMP and G600 may reduce the frequency of gout flares.
Funding Funding was provided by LactoPharma (a joint venture between Fonterra Ltd, Fonterra R&D Ltd and Auckland UniServices Ltd) and the New Zealand Government Foundation for Research Science and Technology.
Competing interests This work was funded by LactoPharma (a joint venture between Fonterra Ltd, Fonterra R&D Ltd and Auckland UniServices Ltd) and the New Zealand Government Foundation for Research Science and Technology. BK-S, AM and KP are employees of Fonterra Co-operative Group Ltd. AM, ND and KP are named inventors on a patent application related to milk products and gout.
Patient consent Obtained.
Ethics approval The study was approved by the Northern Y regional ethics committee.
Provenance and peer review Not commissioned; externally peer reviewed.