Serum ionized magnesium acts as an independent protective factor against bone erosion in patients with gouty arthritis: a cross-sectional study

Abstract

Background: Gouty arthritis is a common inflammatory arthritis. The recurrent gout attacks severely damage the joint's function, lead to bone erosion, and affect bone metabolism. The role of magnesium (Mg) ions in bone homeostasis has been recognized, whereas its specific relationship with gouty bone erosion remains unclear. This study examined the association between serum ionized Mg levels and bone erosion in patients with gout arthritis.

Methods: A total of 769 patients with gout arthritis were included in the study. Participants were classified into four groups based on the quartiles of the serum ionized Mg level. Logistic regression analysis assessed the association between serum ionized Mg and bone erosion.

Results: Compared to patients without bone erosion, serum ionized Mg levels were lower in gout patients with bone erosion (p<0.001). When dividing serum ionized Mg into quartiles, the prevalence rate of bone erosion in group Q1, representing the patients with the lowest serum ionized Mg levels, was notably higher than in Q2, Q3, and Q4 (60.2% vs. 43.6%, 45.6%, 40.3%, p<0.001). Multiple logistic regression analysis revealed that patients in Q2-Q4 had a lower odds ratio (OR) of bone erosion compared to those in Q1 (ORs were 0.520, 0.533, and 0.411 in Q2-Q4, respectively, p<0.001).

Conclusion: The incidence of bone erosion is higher in gout arthritis patients with lower serum ionized Mg levels. High serum ionized Mg levels may be an independent protective factor for bone erosion in gout arthritis. Thus, Mg supplementation may be a promising approach to prevent or slow down the development of bone erosion in gouty arthritis.

Keywords: biochemical markers of bone turnover; bone erosion; gout; gouty arthritis; magnesium.

Figure 1

Flowchart of study participants. In this study, we excluded patients with specific joint diseases, acute complications, comorbidities or medications affecting serum Mg levels, bone or mineral metabolism disorders, and incomplete clinical data.

Figure 2

The DECT images of gout patients with bone erosion and without bone erosion. (A) and (D) showed the hand/wrist area. (B, C, E) and (F) showed the foot/ankle area. White arrows present bone erosion in (A–C) No bone erosion was observed in (D–F). .

Figure 3

Distribution of serum ionized Mg levels in gout patients with and without bone erosion. Student’s t-test was employed to analyze the difference between the two groups. The serum ionized Mg level was significantly lower in the bone erosion group than the without bone erosion group (p<0.001).

Figure 4

The prevalence of bone erosion in different groups of serum ionized magnesium levels. Group by quartile of serum ionized Mg: Q1: serum ionized Mg ≤0.83 mmol/L; Q2: 0.83

Figure 5

Forest plot of multivariate logistic regression. * presents statistically significant. OR (95%CI), odds ratio (95% confidence interval). SBP, systolic blood pressure; DBP, diastolic blood pressure; HbA1c, glycated hemoglobin; FPG, fasting plasma glucose; FFA, free fatty acid; SUA, serum uric acid; SCr, serum creatinine; Ca, serum ionized calcium; P, serum phosphorus.