Abstract
Background: Gout, a prevalent inflammatory arthropathy in Māori and Pacific populations, including Samoa, results from hyperuricemia and the formation of monosodium urate crystals (MSU). This research encompasses two key aspects of gout management and understanding in these populations: genetic variant associations with gout and the potential efficacy of curcumin, a natural anti-inflammatory agent, in its treatment.
Methods: The genetic component of the study involved 1146 gout cases and 1269 controls from Polynesian ancestry in Aotearoa New Zealand. Low pass whole genome sequencing (WGS) was utilized to identify Polynesian-specific and rare or novel variants of the ABCG2, PKD2, and IL37 genes. The clinical trial in Samoa, a feasibility study for a larger randomized controlled trial (RCT), enrolled 60 gout patients. Participants were randomly assigned to receive either curcumin or placebo capsules over three months, assessing not only curcumin’s efficacy but also feasibility issues including participant adherence, recruitment feasibility, patient willingness to participate, donate body tissues, accept randomization, and the effectiveness of the blinding mechanism. Gout outcome measures were also analysed.
Results: The genetic study identified several Polynesian-specific ABCG2 variants linked with gout and urate, including a significant variant chr4_88107915_C_T, and replicated previous findings of gout-associated variants. The trial in Samoa faced challenges due to the COVID-19 pandemic, leading to significant loss to follow-up. However, it demonstrated successful recruitment and randomization, good patient adherence, and effective blinding despite some issues with missing data. The limited available data suggested a trend towards the efficacy of curcumin in managing gout symptoms, but these results were inconclusive due to the disrupted follow-up.
Conclusion: This study provides valuable insights into the genetic predispositions to gout in Polynesian populations and lays the groundwork for future, more conclusive research on curcumin's role in gout management. The findings from the genetic analysis contribute to a deeper understanding of gout's pathogenesis in these communities, while the preliminary data from the clinical trial in Samoa underline the feasibility of conducting larger-scale RCTs in this setting, despite the challenges posed by external factors like the COVID-19 pandemic.