Increased risk of osteoporosis with hysterectomy: A longitudinal follow-up study using a national sample cohort.

BACKGROUND

Premenopausal hysterectomy is associated with a decreased ovarian reserve, follicular atresia, and subsequently reduced long-term estrogen secretion. Therefore, women who undergo hysterectomy will experience greater gradual bone mineral loss than women with an intact uterus and have an increased risk of osteoporosis.

OBJECTIVE

This study aimed to evaluate the association between hysterectomy without/with bilateral oophorectomy and the occurrence of osteoporosis using a national sample cohort from South Korea.

STUDY DESIGN

Using the national cohort study from the Korean National Health Insurance Service, we extracted data for patients who had undergone hysterectomy (n=9082) and for a 1:4 matched control group (n=36,328) and then analyzed the occurrence of osteoporosis. The patients were matched according to age, sex, income, region of residence, and medical history. A Cox proportional hazards model was used to analyze the hazard ratios and 95% confidence intervals. Subgroup analyses were performed based on age and bilateral oophorectomy status. The age of the participants was defined as the age at the time of hysterectomy.

RESULTS

The adjusted hazard ratio for osteoporosis was 1.45 (95% confidence interval, 1.37-1.53, P<.001) in the hysterectomy group. The adjusted hazard ratios for osteoporosis in the different age subgroups of this group were 1.84 (95% confidence interval, 1.61-2.10) for ages 40-44 years, 1.52 (95% confidence interval, 1.39-1.66) for ages 45-49 years, 1.44 (95% confidence interval, 1.28-1.62) for ages 50-54 years, 1.61 (95% confidence interval, 1.33-1.96, all P<.001) for ages 55-59 years, and 1.08 (95% confidence interval, 0.95-1.23, P=.223) for ages ≥60 years. The adjusted hazard ratios for osteoporosis according to hysterectomy/oophorectomy status were 1.43 (95% confidence interval, 1.34-1.51) in the hysterectomy without bilateral oophorectomy group and 1.57 (95% confidence interval, 1.37-1.79) in the hysterectomy with bilateral oophorectomy group.

CONCLUSION

The occurrence of osteoporosis was increased in patients who had undergone hysterectomy compared with that in matched control subjects regardless of bilateral oophorectomy status.