Association between higher serum uric acid levels within the normal physiological range and changes of lumbar spine bone mineral density in healthy Chinese postmenopausal women: a longitudinal follow-up study

Association between serum uric acid levels and bone mineral density in patients with osteoporosis: a cross-sectional study

BACKGROUND

The results of studies exploring the association between serum uric acid (SUA) and bone mineral density (BMD) have been controversial and inconsistent. We thus sought to explore whether SUA levels were independently associated with BMD in patients with osteoporosis (OP).

METHODS

This cross-sectional analysis was conducted using prospectively obtained data from the Affiliated Kunshan Hospital of Jiangsu University database pertaining to 1,249 OP patients that were hospitalized from January 2015 - March 2022. BMD was the outcome variable for this study, while baseline SUA levels were the exposure variable. Analyses were adjusted for a range of covariates including age, gender, body mass index (BMI) and a range of other baseline laboratory and clinical findings.

RESULTS

SUA levels and BMD were independently positively associated with one another in OP patients. Following adjustment for age, gender, BMI, blood urae nitrogen (BUN), and 25(OH)D levels, a 0.0286 g/cm² (β, 0.0286; 95% confidence interval [CI], 0.0193-0.0378, P < 0.000001) increase in BMD was observed per 100 μmol/L rise in SUA levels. A non-linear association between SUA and BMD was also observed for patients with a BMI < 24 kg/m², with a SUA level inflection point at 296 μmol/L in the adjusted smoothed curve.

CONCLUSIONS

These analyses revealed SUA levels to be independently positively associated with BMD in OP patients, with an additional non-linear relationship between these two variables being evident for individuals of normal or low body weight. This suggests that SUA levels may exert a protective effect on BMD at concentrations below 296 μmol/L in normal- and low-weight OP patients, whereas SUA levels above this concentration were unrelated to BMD.

Interplay between fat, muscle, bone mass, and oteophytes and risk for tophaceous gout

Tophaceous gout is a common arthritis caused by the deposition of urate crystals and is related to limited joint function. Although there are reports that uric acid (UA) is associated with bone mineral density (BMD), little is known about the relationship between UA, osteophytes, and muscle. This cross-sectional case-control study was performed in patients with tophaceous gout. The control group included patients without gout. All subjects underwent BMD and body composition analyses. Age, sex, alcohol consumption, smoking, and radiography of both knees were recorded. Adjusted ORs for tophaceous gout were calculated using the logistical regression models. A total of 150 male patients were enrolled, including 65 individuals with tophaceous gout and 85 without gout. The mean age of the patients with tophaceous gout was 59.94±12.40 years, while that of individuals without gout was 61.29±11.57 years (p=0.492). Patients with tophaceous gout have a higher mean body mass index, fat mass, appendicular lean mass, BMD, and osteophytes. Multiple logistic regression analysis revealed that fat mass (OR 2.01, 95% CI 1.27 to 3.18), appendicular lean mass (OR 4.27, 95% CI 1.86 to 9.83), and osteophytes (OR 5.88, 95% CI 1.72 to 20.13) were significantly associated with tophaceous gout. In the current study, higher fat mass, high muscle mass, and osteophyte formation were found to increase the risk of tophaceous gout, as the association is the most than can be inferred from a cross-sectional study. Therefore, reducing body fat and weight management may prevent tophaceous gout.

The relationship between uric acid and total femur bone mineral density in hypertensive and non-hypertensive populations

OBJECTIVE

This study aimed to explore the association between uric acid (UA) and total femur bone mineral density (BMD) in hypertensive and non-hypertensive groups.

METHODS

We conducted a cross-sectional study of 13,108 participants in the NHANES database, including 4,679 hypertensive and 8,429 non-hypertensive subjects. A weighted multiple linear regression analysis was conducted to explore the association between UA and total femur BMD.

RESULTS

In the hypertensive group, the relationship between UA and total femur BMD was positive [β, 3.02 (95% CI, -0.44 to 6.48), p = 0.0962). In the non-hypertensive group, the association was significantly positive [β, 5.64 (95% CI, 2.06-9.22), p = 0.0038]. In gender-stratified analysis, UA was analyzed as a continuous variable and a categorical variable (quartile). The significantly positive association was present in both the hypertensive male group [β, 5.10 (95% CI, 0.98-9.21), p for trend = 0.0042] and non-hypertensive male group [β, 10.63 (95% CI, 6.32-14.94), p for trend = 0.0001]. A smooth curve fitting showed that in the hypertensive male group, the relationship between UA and total femur BMD was an inverted U-shaped curve. In the hypertensive female group, the relationship was basically negative. In the non-hypertensive population, the relationship between UA and total femur BMD was an inverted U curve in both men and women.

CONCLUSION

In the hypertensive male group, the association between UA and total femur BMD was an inverted U-shaped curve. As to women, the relationship was basically negative. In the non-hypertensive group, the association between UA and total femur BMD was an inverted U-shaped curve in different genders.