Association of pro-inflammatory cytokines with QCT-measured bone mineral density and its gender difference in a Chinese population - a pilot study.

The primary objective of this study was to explore the association of pro-inflammatory cytokines with quantitative computed tomography (QCT)-measured bone mineral density (BMD) and its sexual difference in a Chinese population. In a cross-sectional study, a total of 85 participants aged 48-85 years were recruited and classified into three groups: normal bone mass with BMD > 120 mg/cm³, osteopaenia with BMD 80-120 mg/cm³, and osteoporosis with BMD < 80 mg/cm³. ANOVA analysis and multivariable ordinal logistic regression was used to estimate the associations of interest. The proportions of osteoporosis, osteopaenia, and normal BMD were 29.41% (25), 37.65% (32), and 32.94% (28), respectively. Males had the highest proportion of osteopaenia while females had osteoporosis (p < 0.01). In contrast with the null findings in males, significant statistical difference was observed in females. Compared to the normal BMD, the OR for increasing IL-6 level of decreasing BMD groups (osteoporosis and/or osteopaenia) was 9.50 (95% CI: 1.44-62.80). TNF-a and IL-17 tended to show an increased risk (OR > 1) but did not reach significance. Current OR result cannot confirm these relationships of IL-1b, and ORs of PAI-1 and MCP-1 are too close to 1 to determine the practical meaning. IL-6 is an obviously independent risk factor of QCT-measured osteoporosis in Chinese females. Sex hormones and fat-related factors are important confounders in the research of osteoimmunology.