Exploring the link between serum betaine levels and hyperuricemia risk in middle-aged and older adults: insights from a prospective cohort study.

PURPOSE

Betaine is connected to various cardio-metabolic outcomes, yet its relationship with hyperuricemia remains uncertain. We aimed to longitudinally investigate the association between serum betaine levels and the risk of hyperuricemia in middle-aged and older adults.

METHODS

This study utilized data from the Guangzhou Nutrition and Health Study (GNHS). Participants were enrolled between 2008 and 2010, with follow-ups conducted every three years, comprised an analysis sample of 2204 adults aged 40-75. Baseline serum betaine levels were assessed using high-performance liquid chromatography-tandem mass spectrometry. Serum uric acid (SUA) levels were measured at baseline and every three years thereafter. Linear mixed-effects models (LMEMs) and generalized estimating equations (GEEs) were employed to examine the longitudinal association between serum betaine levels and SUA levels, as well as hyperuricemia risk, respectively.

RESULTS

LMEMs indicated that compared to individuals in the lowest quartile (Q1) of serum betaine levels, those in the highest quartile (Q4) exhibited the lowest SUA levels (Q4 vs. Q1: β -8.19, 95% CI -16.32 to -0.06, P-trend = 0.023). Each standard deviation increase in betaine (16.5 µmol/L) was associated to SUA levels decrease of -3.28 (-6.10, -0.45). Results from the GEE model suggested a 19% reduction in the odds of hyperuricemia (OR = 0.81; 95% CI: 0.68, 0.95, P-trend = 0.051) in the Q4 group compared to the Q1 category.

CONCLUSION

Our findings highlight a negative association between serum betaine levels and SUA levels, as well as the risk of hyperuricemia in middle-aged and older adults, which is more pronounced in individuals with better dietary quality.

TRIAL REGISTRATION

This trial was registered at clinicaltrials.gov as NCT03179657. Website: https://clinicaltrials.gov/ct2/show/NCT03179657.