High-density lipoprotein (HDL) levels are associated with inflammation and the occurrence of osteoporosis in patients with rheumatoid arthritis (RA), according to study results published in Scandinavian Journal of Clinical and Laboratory Investigation.
In a retrospective study of 412 patients with RA (73.5% women) diagnosed at the Second Affiliated Hospital of Nanchang University, Nanchang, China, the investigators aimed to evaluate the clinical significance of HDL levels in patients with RA with and without osteoporosis.
Serum levels of total cholesterol, triglycerides, HDL, and low-density lipoprotein (LDL) were compared between patients with RA with and without osteoporosis; healthy control participants (n=100; 75% women) were also included in the study.
Compared with healthy control participants, patients with RA had lower serum levels of total cholesterol (84.6 vs 79.2 mg/dL; P <.001) and HDL (27.0 vs 21.6 mg/dL; P <.001) and higher serum levels of triglycerides (27.0 vs 37.8 mg/dL; P <.001); however, LDL levels were not significantly different between groups.
Among the RA cohort, the percentage of women was higher in groups with vs without osteoporosis (81.4% vs 70.0%; P =.015). Compared with individuals without osteoporosis, those with osteoporosis had higher serum levels of total cholesterol (77.4 vs 81.0 mg/dL; P =.002) and HDL (19.8 vs 23.4 mg/dL; P <.001).
After adjusting for sex, age, and body mass index, serum levels of total cholesterol (odds ratio [OR], 1.6; 95% CI, 1.2-2.2; P =.004) and HDL (OR, 10.2; 95% CI, 4.5-23.0; P <.001) were associated with osteoporosis in patients with RA.
Patients were divided into groups based on serum HDL levels to compare associations with laboratory parameters. Compared with patients with HDL levels ≥18.9 mg/dL, those with HDL levels ≤18.72 mg/dL had elevated C-reactive protein levels (34.0 vs 46.6 mg/L; P =.005), erythrocyte sedimentation rate (50.0 vs 61.0 mm/h; P <.001), and Disease Activity Score 28 (4.5 vs 4.9; P =.001).
The rate of osteoporosis was significantly lower in the HDL ≤18.72 mg/dL group compared with the HDL ≥18.90 mg/dL group (14.6% vs 44.9%; P <.001); however, the rate of cardiovascular disease (5.4% vs 1.3%; P =.033) was higher.
Researchers noted that only patients treated with conventional disease modifying antirheumatic drugs were included in the study, which may limit the generalizability of results to all patients with RA.
“HDL is associated with [osteoporosis] incidence and inflammatory status in patients [with RA] and can be used as a predictor of [osteoporosis] and a good indicator of disease monitoring in patients [with RA],” the researchers concluded.
Zeng T, Tan L, Yu J, Wu Y. High density lipoprotein in rheumatoid arthritis: emerging role in predicting inflammation level and osteoporosis occurrence [published online April 11, 2020]. Scand J Clin Lab Invest. doi:10.1080/00365513.2020.1747109