Folic acid supplementation can improve histopathologic aspects of gastric precancerous conditions (GPC), including gastric mucosal atrophy and intestinal metaplasia, according to results of a meta-analysis of relevant research.
The results, say the authors, provide evidence for the potential clinical use of folic acid in the management of GPC.
“We believe doctors can try to use folic acid to halt or reverse progression of gastric precancerous conditions, thereby reducing the incidence rate of gastric cancer,” investigator Jinhao Zeng, PhD, with Hospital of Chengdu University of Traditional Chinese Medicine, said in an interview.
Dr. Zeng cautioned, however, that the number of relevant studies “remains relatively inadequate, and the results should be interpreted with caution.”
David Johnson, MD, professor of medicine and chief of gastroenterology at the Eastern Virginia School of Medicine, Norfolk, who wasn’t involved in the study, also urged caution in interpreting the results.
“Overall, folate supplementation is unlikely to be harmful, but these data should not be used as justification for risk reduction,” Dr. Johnson said in an interview.
The study was published online in BMC Gastroenterology.
Examining prevention, treatment effects
The study is believed to be the first meta-analysis to examine the effects of folic acid on prevention and treatment for patients with GPC. The analysis included 13 randomized controlled trials that had a total of 1,252 adults with GPC living in China.
A meta-analysis of five studies showed a statistically significant positive treatment effect of folic acid supplementation on gastric mucosal atrophy (relative risk, 1.61; 95% confidence interval 1.07 – 2.41), Dr. Zeng and colleagues reported.
A meta-analysis of two trials showed a statistically significant effect of folic acid on reversal of intestinal metaplasia (RR, 1.77; 95% CI, 1.32-2.37), they also found.
“Our study indicates that folic acid has a beneficial effect in the treatment of pathological changes of GPC when the dose was maintained at 20-30 mg/d and the duration of treatment was maintained at 3-6 months,” they wrote.
Folic acid supplementation did not appear to be effective for GPC symptom relief.
The authors said that, in a separate analysis, they confirmed that folic acid can inhibit development of gastric mucosal carcinogenesis by affecting the levels of gastrin and pepsinogen.
More study needed
Commenting on the study, Judith Kim, MD, division of gastroenterology and hepatology, New York University Langone Health, said prior studies have evaluated whether folic acid supplementation is associated with a lower risk of gastric cancer, but the results have been “mixed and inconclusive.”
“While there have been prior meta-analyses on folic acid and gastric cancer, this study is noteworthy, as it evaluated the impact of folic acid on precancerous lesions, for which there is no current treatment,” Dr. Kim said.
“Currently, there is no recommendation for folic acid supplementation for the treatment or prevention of GPC and gastric cancer,” Dr. Kim said. “There has been interest in folic acid as a chemopreventive agent, given its potential protective role against DNA damage, but randomized control trials have yet to confirm these benefits.”
The analysis by Dr. Zeng and colleagues “supports the need for larger randomized controlled trials to further study this association,” Dr. Kim said.
“Given the study’s small size and limitation to a Chinese population (who have a higher incidence of precancerous lesions and gastric cancer than the general US population), I would caution against folic acid use for the sole purpose of GPC prevention, as there could be negative side effects of supplementation,” she advised.
The study was supported by the National Natural Science Foundation of China, the Hospital of Chengdu University of Traditional Chinese Medicine, and Project of Sichuan Administration of Traditional Chinese Medicine. Dr. Zeng, Dr. Johnson, and Dr. Kim reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.