Vitamin D Insufficiency and Musculoskeletal Symptoms in Breast Cancer Survivors on Aromatase Inhibitor Therapy

Abstract

Breast cancer survivors on aromatase inhibitor therapy often experience musculoskeletal symptoms (joint pain and stiffness, bone and muscle pain, and muscle weakness), and these musculoskeletal symptoms may be related to low serum levels of vitamin D. The primary purpose of this pilot exploratory study was to determine whether serum levels of 25-hydroxyvitamin D concentration (25 [OH] D) were below normal (<30 ng/ml) in 29 breast cancer survivors (BCS) on aromatase inhibitor therapy (AIs) and if musculoskeletal symptoms were related to these low vitamin D levels. The mean serum 25(OH) D level was 25.62 ± 4.93 ng/mL; 86% (n = 25) had levels below 30 ng/mL. Patients reported muscle pain in the neck and back, and there was a significant inverse correlation between pain intensity and serum 25(OH) D levels (r = − 0.422; p <.05 [2-tailed]). This sample of BCS taking AIs had below normal levels of serum 25(OH) D despite vitamin D supplements. This is one of the few studies to document a significant relationship between vitamin D levels and muscle pain in BCS on AI therapy. Findings from this pilot study can be used to inform future studies examining musculoskeletal symptoms in BCS on AI therapy and relationships with low serum levels of vitamin D.

Prevalence of serum vitamin D deficiency and insufficiency in cancer: Review of the epidemiological literature

“…Most of the studies (n=10) measured the serum 25(OH)D levels using the radioimmunoassay, while some of the other studies used nichols Advantage assay kit (n=3), high-performance liquid chromatography (n=1), protein binding assay (n=2), competitive immunoluminometric direct assay (n=2) and chemiluminescent immunoassay (n=2). Many of these studies showed a prevalence of vitamin D deficiency >70% (31,(34)(35)(36)(37)48,51,54). A few studies (n=9) reported a prevalence rate between 40 and 70%, while the other studies (n=4) reported rates lower than 40%.…”

Vitamin D Deficiency in Postmenopausal Breast Cancer Survivors

“…We defined vitamin D deficiency as a serum 25-OHD level < 30 ng/mL, which is consistent with previous articles cited. 10 …”

“…9 Lastly, there may be a relationship between vitamin D levels and AI-associated arthralgia. 10,11 Vitamin D is a fat-soluble vitamin that regulates bone modeling and calcium absorption. Although moderate amounts of the vitamin from such foods as milk and fatty fish are absorbed from the gastrointestinal tract, the majority of vitamin D is produced in the body when 7-dehydrocholesterol in the skin is exposed to ultraviolet B (UVB) radiation to produce vitamin D 3 (cholecalciferol).…”

Vitamin D threshold to prevent aromatase inhibitor-induced arthralgia: a prospective cohort study

“…The role of vitamin D deficiency in AI induced arthralgia is controversial [33], with some studies demonstrating a positive association between vitamin D deficiency and symptoms [34]. The mechanism for this association is unclear, It has been proposed [18] that the AI induced reduction in estrogen may unmask subclinical osteomalacia through the loss of estrogen mediated activation of 1alpha hydroxylase [35], the vitamin D receptor [36,37] and/or vitamin D binding protein.…”