No Significant Effect of Elevated Urate on Bone Turnover Markers in Older Women

Among postmenopausal women, hyperuricemia, induced by inosine supplementation, has no significant effect on bone turnover markers or bone mineral density (BMD), according to study results published in Arthritis & Rheumatology.

Previous studies have shown a positive correlation between serum urate and BMD. The objective of the current study was to investigate the association between elevated serum urate levels, induced by inosine supplementation, and bone turnover markers in postmenopausal women.

In the 6-month, randomized, double-blind, placebo-controlled trial (ANZCTR Identifier: ACTRN12617000940370), the researchers included women aged 55 years or greater. All patients had normal kidney function, serum urate less than 0.42 mmol/L (7 mg/dL), and were able to attend study visits. Exclusion criteria included patients with a history of osteoporosis, kidney stones, or gout, previous fragility fractures, and current or past use of medications that may affect bone turnover markers.

The participants were randomly assigned 1:1 to receive placebo or inosine supplements for 6 months. Co-primary endpoints were changes in serum bone turnover markers, including procollagen-1 N-terminal peptide (P1NP) and β-C-terminal telopeptide of type I collagen (β-CTX).

A total of 120 women (60 receiving inosine supplements; mean age, 68 years) were included in the analysis. During the study period, there was a significant increase in serum urate after the administration of inosine supplements (P <.0001). Mean change in serum urate at week 26 was 0.13 mmol/L (2.2 mg/dL) and 0.00 mmol/L (0 mg/dL) in the inosine and placebo group, respectively. At 6 months, there was no significant difference in P1NP or β-CTX values between the 2 groups. In addition, no difference was reported in total body, lumbar spine, or femoral neck BMD during the study period.

Adverse events and serious adverse events were similar between the 2 groups, with infection being the primary cause of serious adverse events.

The study had several limitations, including the use of bone turnover markers instead of BMD and the relatively short follow-up period.

“While urate may be a marker of BMD, these findings do not support the concept that urate has direct biological effects on bone turnover,” the researchers concluded.

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Dalbeth N, Horne A, Mihov B, et al. Elevated urate does not alter bone turnover markers. Randomized controlled trial of inosine supplementation in post-menopausal women. Arthritis Rheumatol. Published online February 14, 2021. doi:10.1002/art.41691