Expanding the Evidence with a Larger Patient Group

Until now, confirming those earlier findings in a much larger population has been difficult. Because nicotinamide is available over the counter, its use is rarely documented in medical records. To overcome that obstacle, researchers turned to the Veterans Affairs (VA) Corporate Data Warehouse, where nicotinamide is listed on the VA's official formulary.

Using these records, the research team reviewed the outcomes of 33,833 veterans who received baseline treatment with 500 milligrams of nicotinamide twice daily for more than 30 days. They tracked each patient's next diagnosis of basal cell carcinoma or cutaneous squamous cell carcinoma.

Large Study Reveals Significant Risk Reduction

Among those studied, 12,287 patients had taken nicotinamide, while 21,479 had not. The researchers found a 14% overall decrease in skin cancer risk among nicotinamide users. For those who began taking the supplement after experiencing their first skin cancer, the risk reduction jumped to 54%. However, this benefit lessened when treatment began after multiple skin cancers had already developed. The effect was strongest for squamous cell carcinoma, one of the most common nonmelanoma skin cancers.

Early Use Could Shift Prevention Strategies

"There are no guidelines for when to start treatment with nicotinamide for skin cancer prevention in the general population. These results would really shift our practice from starting it once patients have developed numerous skin cancers to starting it earlier. We still need to do a better job of identifying who will actually benefit, as roughly only half of patients will develop multiple skin cancers,"

said the study's corresponding author, Lee Wheless, MD, PhD, assistant professor of Dermatology and Medicine at Vanderbilt University Medical Center and staff physician at the VA Tennessee Valley Healthcare System.

Findings in Transplant Patients

The team also evaluated 1,334 patients who were immunocompromised due to solid organ transplants. In this group, overall risk reduction was not statistically significant, although early use of nicotinamide was linked to fewer cases of cutaneous squamous cell carcinoma.

Research Collaboration and Support

Wheless's work was supported by a Department of Veterans Affairs grant (IK2CX002452). Co-authors from Vanderbilt University included Katyln Knox, Rachel Weiss, Siwei Zhang, PhD, Lydia Yao, MS, Yaomin Xu, PhD, and Kyle Maas.