Multiyear vitamin and garlic supplementation yielded statistically significant reductions in gastric cancer incidence and mortality. - GreenMedInfo Summary
Effects oftreatment and vitamin and garlic supplementation on gastric cancer incidence and mortality: follow-up of a randomized intervention trial.
BMJ. 2019 Sep 11 ;366:l5016. Epub 2019 Sep 11. PMID: 31511230
Wen-Qing Li
OBJECTIVE: To assess the effects oftreatment, vitamin supplementation, and garlic supplementation in the prevention of gastric cancer.
DESIGN: Blinded randomized placebo controlled trial.
SETTING: Linqu County, Shandong province, China.
PARTICIPANTS: 3365 residents of a high risk region for gastric cancer. 2258 participants seropositive for antibodies towere randomly assigned totreatment, vitamin supplementation, garlic supplementation, or their placebos in a 2×2×2 factorial design, and 1107seronegative participants were randomly assigned to vitamin supplementation, garlic supplementation, or their placebos in a 2×2 factorial design.
INTERVENTIONS: treatment with amoxicillin and omeprazole for two weeks; vitamin (C, E, and selenium) and garlic (extract and oil) supplementation for 7.3 years (1995-2003).
MAIN OUTCOME MEASURES: Primary outcomes were cumulative incidence of gastric cancer identified through scheduled gastroscopies and active clinical follow-up through 2017, and deaths due to gastric cancer ascertained from death certificates and hospital records. Secondary outcomes were associations with other cause specific deaths, including cancers or cardiovascular disease.
RESULTS: 151 incident cases of gastric cancer and 94 deaths from gastric cancer were identified during 1995-2017. A protective effect oftreatment on gastric cancer incidence persisted 22 years post-intervention (odds ratio 0.48, 95% confidence interval 0.32 to 0.71). Incidence decreased significantly with vitamin supplementation but not with garlic supplementation (0.64, 0.46 to 0.91 and 0.81, 0.57 to 1.13, respectively). All three interventions showed significant reductions in gastric cancer mortality: fully adjusted hazard ratio fortreatment was 0.62 (95% confidence interval 0.39 to 0.99), for vitamin supplementation was 0.48 (0.31 to 0.75), and for garlic supplementation was 0.66 (0.43 to 1.00). Effects oftreatment on both gastric cancer incidence and mortality and of vitamin supplementation on gastric cancer mortality appeared early, but the effects of vitamin supplementation on gastric cancer incidence and of garlic supplementation only appeared later. No statistically significant associations were found between interventions and other cancers or cardiovascular disease.
CONCLUSIONS: treatment for two weeks and vitamin or garlic supplementation for seven years were associated with a statistically significant reduced risk of death due to gastric cancer for more than 22 years.treatment and vitamin supplementation were also associated with a statistically significantly reduced incidence of gastric cancer.
TRIAL REGISTRATION: ClinicalTrials.gov NCT00339768.
