Vitamin D deficiency and bone mineral density in postmenopausal women receiving aromatase inhibitors for early breast cancer.
OBJECTIVE
Aromatase inhibitors (AI) treatment leads to an increased risk of bone loss and fractures. In a group of women with early breast cancer (EBC) and baseline Vitamin D deficiency (<30 ng/ml) who are treated with AI, we aim to describe: serum levels of Vitamin D, bone mineral density (BMD), calcium intake, and the increase of serum 25(OH)D accomplished in 3 months of treatment with Vitamin D supplements.


METHODS
Prospective, non-randomized clinical trial.


METHODS
In 232 consecutively included women with EBC in treatment with AI, we assessed baseline calcium intake, serum levels of 25(OH)D, BMD and, spine X-ray. All received Calcium and Vitamin D supplements, and those with vitamin deficiency received 16,000 IU Vitamin D every 2 weeks. Serum levels of 25(OH)D were newly assessed after treatment. All the baseline evaluation was performed before starting AI treatment.


RESULTS
Mean age at baseline (+/-SD) was 63.2+/-8.8 years. In 150 (64.9%) cases, the women had been treated previously with tamoxifen; 101 (43.7%) started exemestane, 119 (51.5%) letrozole, and 11 (4.8%) anastrozole. The AI were initiated within 6 weeks after surgery or after the last cycle of chemotherapy. At baseline, 88.1% had 25(OH)D levels <30 ng/ml, 21.2% had severe deficiency (<10 ng/ml), and 25% of the participants had osteoporosis. Mean daily calcium intake was low (841+/-338). We found a significant association between 25(OH)D levels and BMD at baseline, which remained significant in femoral neck BMD after multivariate adjustment. Plasma 25(OH)D levels improved significantly at 3 months follow-up in those treated with high dose Vitamin D supplements: mean increase 32.55 ng/ml (95%CI 28.06-37.03).


CONCLUSIONS
Our study suggests a high prevalence of commonly unrecognized Vitamin D deficiency in women with EBC treated with AI, a known osteopenic agent. Our results support the need for a routine assessment of 25(OH)D levels and, when necessary, supplementation in these patients.
Nogues
Xavier
X
Internal Medicine Department, URFOA-IMIM, RETICEF, Hospital del Mar, Autonomous University of Barcelona, Barcelona, Spain. xnogues@hospitaldelmar.cat
Servitja
Sonia
S
Peña
Maria Jesus
MJ
Prieto-Alhambra
Daniel
D
Nadal
Rosa
R
Mellibovsky
Leonardo
L
Albanell
Joan
J
Diez-Perez
Adolfo
A
Tusquets
Ignasi
I
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000008:administration & dosage; D047072:Aromatase Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D015519:Bone Density / Q000187:drug effects*; D001943:Breast Neoplasms / Q000150:complications* / Q000188:drug therapy; D002118:Calcium / Q000008:administration & dosage; D005260:Female; D005269:Femur; D006801:Humans; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology; D017698:Postmenopause; D011446:Prospective Studies; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use*; D014808:Vitamin D Deficiency / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology
D000970:Antineoplastic Agents; D047072:Aromatase Inhibitors; D014807:Vitamin D; C104450:25-hydroxyvitamin D; D002118:Calcium