Low Vitamin D Linked to More Pain and Opioid Use After Breast Cancer Surgery

New research suggests that breast cancer patients with low levels of vitamin D may experience significantly higher levels of pain and receive more opioid medication following surgery.

The study, published in the journal Regional Anesthesia & Pain Medicine, indicates that patients suffering from a vitamin D deficiency are three times more likely to report moderate to severe postoperative pain compared to those with sufficient levels. Researchers suggest that identifying and addressing these deficiencies before a patient undergoes a radical mastectomy could be a key factor in improving recovery outcomes.

The link between vitamin D and pain

Vitamin D is increasingly recognized for its role beyond bone health. Emerging evidence suggests the vitamin helps control how the body processes and feels pain, likely due to its anti-inflammatory properties and its influence on the immune system.

Because vitamin D deficiency is commonly reported among patients with breast cancer, a team of researchers at Fayoum University Hospital in Egypt conducted a prospective observational study to measure its impact on surgical recovery. The study followed 184 patients scheduled for a radical mastectomy between September 2024 and April 2025.

Participants were divided into two groups: those who were vitamin D deficient, defined as having levels below 30 nmol/L, and those who were vitamin D sufficient, with levels above 30 nmol/L. The average age of patients in both groups was similar, at 44 and 42 respectively.

Increased pain and opioid consumption

The results showed a stark contrast in the recovery period. During the first 24 hours after surgery, patients in the vitamin D deficient group were much more likely to report moderate pain, defined as a 4 to 6 on a 10-point scale. The researchers noted that no patients in either group reported severe pain (a score of 7 or higher), meaning the primary difference was the reduction of pain from moderate to mild levels in the group with sufficient vitamin D.

This increase in pain led to a significant difference in the amount of medication required for relief. While the amount of fentanyl administered during surgery was only modestly higher in the deficient group (an average of 8 μg more), the postoperative requirements were much greater.

Patients were given access to patient-controlled analgesia, allowing them to press a button to receive doses of tramadol, a strong opioid, as needed. Those with low vitamin D levels consumed an average of 112 mg more tramadol than their counterparts with sufficient levels.

Risks of opioid use

The increased use of opioids is a concern for clinicians due to the potential for side effects and long-term risks. Opioid drugs are known to cause nausea, vomiting, drowsiness and confusion, and they carry a risk of dependency or addiction.

The study found that postoperative nausea was more frequent in the vitamin D deficient group. Furthermore, vomiting occurred only among patients in the deficient group, though researchers noted this specific difference was small and not statistically significant.

Future implications for patient care

The researchers concluded that there is a clear association between preoperative vitamin D deficiency and higher occurrences of postoperative pain and opioid use. However, the study authors also noted several limitations. Because the research was observational and conducted at a single medical center, it cannot definitively prove that the low vitamin D levels caused the increased pain. Additionally, the study did not measure inflammatory markers or account for other factors that can influence pain perception, such as anxiety, depression, cancer stage or sleep quality.

Despite these limitations, the study offers a potential pathway for improving the surgical experience for patients with breast cancer. Ensuring that vitamin D levels are checked and corrected before surgery could lead to more comfortable recoveries and a reduced need for powerful opioid painkillers.

Editor's note: This article is for informational purposes only and is not a substitute for professional medical advice, as your own experience will be unique. Use this article to guide discussions with your oncologist. Content was generated with AI, reviewed by a human editor, but not independently verified by a medical professional.

References

“Low vitamin D levels linked to more pain after breast cancer surgery,” news release.

“Association between preoperative vitamin D level and postoperative pain in patients undergoing breast cancer surgery: a prospective observational study” by Dr. Mohamed Hasan Ragab et al., Regional Anesthesia and Pain Medicine.

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