Postmenopausal, Vitamin D-Deficient Women May Experience More Pain After Total Knee Replacement

A new study published in Menopause suggests that vitamin D deficiency, smoking, and high body mass index are independent risk factors for increased pain following a total knee replacement in postmenopausal women, according to a press release from the North American Menopause Society (NAMS).

Vitamin D deficiency is a major global issue, with an estimated 60% of adults having insufficient levels of the vitamin, which is known to promote bone and soft tissue health, according to the release. Estrogen deficiency has also been associated with decreased levels of vitamin D in perimenopausal women, as well as a sedentary lifestyle and lack of sun exposure.

In the new study, investigators aimed to establish the effect of vitamin D levels on function outcomes and risk factors of moderate-to-severe pain in postmenopausal women after total knee replacement. The procedure is typically recommended for treating advanced knee osteoarthritis when nonsurgical treatment is no longer effective, and although it is a safe procedure, many women experience postoperative pain, according to NAMS.

Earlier research has identified factors that play a role in determining the amount of pain women feel after undergoing knee replacement surgery, including postmenopausal status and low estrogen levels among women primarily aged 50 to 59 years. This new study suggests a link between vitamin D deficiency and a greater risk of postoperative pain, according to the authors.

Furthermore, the investigators found a high prevalence (67.3%) of vitamin D deficiency in postmenopausal women scheduled for total knee replacement. These findings align with previous studies that suggested that vitamin D deficiency is associated with the development of osteoarthritis, as well as muscle cramps, bone pain, walking difficulty, decreased bone mineral density, and fractures.

The results of studies such as these could provide valuable insights to clinicians evaluating postmenopausal women before major joint surgeries, according to NAMS.

“This study found that high body mass index, smoking, and vitamin D deficiency were independent risk factors for moderate to severe postoperative pain after knee replacement in postmenopausal women,” said NAMS Medical Director Stephanie Faubion, MD, MBA, FACP, NCMP, IF, in the press release. “Additionally, those with preoperative vitamin D deficiency had poorer functional outcomes. These findings highlight opportunities for clinicians to address these modifiable factors before postmenopausal women undergo joint replacement surgeries.”

REFERENCE

Total Knee Replacement May Be More Painful for Vitamin D-Deficient Postmenopausal Women [news release]. North American Menopause Society; May 5, 2021. https://www.menopause.org/docs/default-source/press-release/vitamin-d-and-pain-after-knee-replacement-surgery-5-5-21.pdf. Accessed May 6, 2021.