322. Prolonged Amenorrhea Is Associated with Decreased Hip Bone Mineral Density in Women Living with HIV

Background Women living with HIV (WLWH) have higher rates of long-term amenorrhea (no flow for ≥12 months) than HIV-negative women. However, little is known about the consequences of amenorrhea for WLWH. Both amenorrhea and HIV are associated with lower areal bone mineral density (BMD); though the combined effect of both on BMD remains unclear. In this cross-sectional study we investigated whether prolonged amenorrhea adversely affects BMD among WLWH. Methods We investigated BMD (using a Hologic bone densitometer) and prolonged amenorrhea among WLWH and HIV-negative control women of similar socioeconomic backgrounds aged 19–68 in the CARMA cohort. Participants were stratified by HIV status and history of prolonged secondary amenorrhea defined as a self-reported absence of menses for at least one year in the past or present, occurring at age <45 years and not due to surgery, breastfeeding, pregnancy or hormonal contraception. Hip and spine Z-scores (age- and race- standardized BMD values) were compared between groups using linear models, followed by multivariable analysis of BMD-related factors. Results WLWH (N = 129) had significantly lower hip (mean±SD −0.4 ± 0.9 vs. 0.3 ± 1.1; P < 0.001) and spine (−0.5 ± 1.3 vs. 0.2 ± 1.3; P = 0.001) Z-scores vs. controls (N = 129). Multivariable linear regression found prolonged amenorrhea was independently related to lower hip (P = 0.01), but not spine (P = 0.94) BMD. Within WLWH, the effect of amenorrhea was also additive to that of HIV, with hip Z-scores of -0.8±0.9for those with amenorrhea vs. -0.3±0.8for those normally cycling (P = 0.01). Amongst WLWH, those with prolonged amenorrhea had higher rates of illicit substance use, smoking, chronic opioid therapy, hepatitis C viral infection, and poorer HIV viral control than those with normal menstruation. Conclusion These data suggest that WLWH having prolonged amenorrhea of ≥1 year’s duration are at increased risk for hip bone loss, a finding influenced by comorbid, HIV-associated conditions. Screening WLWH for menstrual history will allow early discovery of osteoporosis risk, and stimulate preventative measures to mitigate bone loss. Disclosures All authors: No reported disclosures.