Associations between hysterectomy and metabolic syndrome: the Multi-Ethnic Study of Atherosclerosis

BACKGROUND: Metabolic syndrome is linked to an increased risk of incident cardiovascular disease and all-cause mortality. Notable associations exist between hysterectomy with bilateral salpingo-oophorectomy and metabolic syndrome. However, there is emerging evidence that even with ovarian conservation, hysterectomy may be independently associated with long-term cardiovascular disease risk. OBJECTIVE: To examine the associations between hysterectomy with ovarian preservation and metabolic syndrome risk in a multiethnic cohort. STUDY DESIGN: We studied 3367 female participants in the Multi- Ethnic Study of Atherosclerosis who had data on self-reported history of hysterectomy, oophorectomy, hystero-oophorectomy, and metabolic syndrome at baseline (2000-2002). We used adjusted logistic regression to assess the cross-sectional associations between hysterectomy and or oophorectomy subgroups and prevalent metabolic syndrome at baseline. Furthermore, we investigated 1355 participants free of baseline metabolic syndrome and used adjusted Cox regression models to evaluate incident metabolic syndrome from examinations 2 (2002-2004) to 6 (2016-2018). RESULTS: The mean age was 59.0 +/- 9.5 years, with 42% White, 27% Black, 19% Hispanic, and 13% Chinese American participants. 29% and 22% had a history of hysterectomy and oophorectomy, respectively. Over median follow-up of 10.5 (3.01-17.62) years, there were 750 metabolic syndrome events. Hysterectomy (hazard ratio, 1.32 [95% confidence interval, 1.01-1.73]) and hystero-oophorectomy (hazard ratio, 1.40 [95% confidence interval, 1.13-1.74]) were both associated with incident metabolic syndrome compared with having neither hysterectomy nor oophorectomy. CONCLUSION: Hysterectomy, even with ovarian preservation, may be independently associated with a higher risk of metabolic syndrome. If other studies confirm these findings, screening and preventive strategies focused on females with ovary-sparing hysterectomies and the mechanisms underpinning these associations may be explored.