(HealthDay News) — Users of valsartan contaminated with N-nitrosodimethylamine (NDMA) seem not to have increased cancer risk, according to a study published online Sept. 12 in The BMJ.
Anton Pottegård, Ph.D., from the University of Southern Denmark in Odense, and colleagues conducted a nationwide cohort study to examine cancer risk associated with exposure to NDMA through contaminated valsartan products. Participants included 5,150 Danish patients with no history of cancer aged 40 years or older who were followed for a median of 4.6 years.
The researchers note that 3,625 participants contributed 7,344 person-years classified as unexposed to NDMA and 3,450 participants contributed 11,920 person-years classified as ever exposed to NDMA. There were 104 cancer outcomes among NDMA unexposed participants and 198 among exposed participants, for an adjusted hazard ratio for overall cancer of 1.09 (95 percent confidence interval, 0.85 to 1.41). Increases in risk for single cancer outcomes were seen for colorectal cancer (hazard ratio, 1.46; 95 percent confidence interval, 0.79 to 2.73) and uterine cancer (hazard ratio, 1.81; 95 percent confidence interval, 0.55 to 5.90).
“This study alone cannot dispel doubts about the potential risk for patients in the longer term, but it helps inform decision making around this episode,” write the authors of an accompanying editorial.