Association between systemic lupus erythematosus and osteoporosis: a mendelian randomization analysis

Systemic Lupus Erythematosus (SLE) and Osteoporosis are two prevalent medical conditions. Previous studies have suggested a possible correlation between SLE and osteoporosis, though the underpinning causal relationship remains largely unknown. The current study aimed to elucidate the causal association between SLE and osteoporosis by employing a Mendelian randomization (MR) approach.

We performed two-sample MR analysis using the inverse variance-weighted (IVW), weighted median, and MR-Egger methods on publicly available summary statistics datasets using a SLE genome-wide association study (GWAS) as an exposure and osteoporosis GWASs in people with East Asia ancestry as outcomes. The pleiotropy and heterogeneity were examined using a variety of techniques, including the MR-Egger intercept, the MR-PRESSO approach, and the Cochran's Q test.

We selected 26 single-nucleotide polymorphisms from a SLE GWAS as instrumental variables for osteoporosis. The IVW (p < 0.05) method results support a potential association between SLE and osteoporosis. MR-Egger intercept (p = 0.82) and MR-PRESSO global test (p = 0.80) did not suggest evidence of horizontal or directional pleiotropy. Cochran's Q test (p = 0.78) showed that there was no heterogeneity between IVs.

The results of MR analysis indicated that SLE is likely associated with an increased risk of osteoporosis incidence. Our findings highlight the need for increased awareness the potential risk of osteoporosis among SLE patients.