In most cases, ln-PFAS concentrations and BMD measurements were negatively associated in men, but only the association between ln-PFOS and FNBMD was statistically significant ([beta] = -0.013; 95% CI: -0.024, -0.002).
In women, ln-PFOS was associated with significantly lower TFBMD and FNBMD, and ln-PFOA was associated with significantly lower TFBMD.
In quartile analyses, women showed significant negative associations between TFBMD and Q2 of PFOA, Q4 of PFOS, and Q4 of PFHxS; and between FNBMD and Q4 of PFOS, relative to the lowest quartile (Q1) of each exposure.
In addition, PFOS was negatively associated with FNBMD, PFOA was negatively associated with TFBMD, and PFNA was positively associated with osteoporosis only.
We observed significant negative associations between PFOS, PFNA, and PFHxS and TFBMD, FNBMD, and osteoporosis in women.
 Nonstandard abbreviations: RCV, reference change value; CTx and NTx, C- and N-terminal telopeptides of collagen 1, respectively; HRT, estrogen replacement therapy; DPD, deoxypyridinoline; BMD, bone mineral density; DXA, dual-energy x-ray absorptiometry; LSBMD, lumbar spine bone mineral density; FNBMD
, femoral neck bone mineral density; and Cr, creatinine.