Global Prevalence of Helicobacter pylori Infection and Incidence of Gastric Cancer Between 1980 and 2022.

BACKGROUND & AIMS: We aimed to assess the secular trend of the global prevalence of Helicobacter pylori (H pylori) infection in adults and children/adolescents and to show its relation to that of gastric cancer incidence. METHODS: We performed a systematic review and meta-analysis to calculate overall prevalence, adjusted by multivariate meta-regression analysis. The incidence rates of gastric cancer were derived from the Global Burden of Disease Study and Cancer Incidence in Five Continents. RESULTS: Of the 16,976 articles screened, 1748 articles from 111 countries were eligible for analysis. The crude global prevalence of H pylori has reduced from 52.6% (95% confidence interval [CI], 49.6%-55.6%) before 1990 to 43.9% (95% CI, 42.3%-45.5%) in adults during 2015 through 2022, but was as still as high as 35.1% (95% CI, 30.5%-40.1%) in children and adolescents during 2015 through 2022. Secular trend and multivariate regression analyses showed that the global prevalence of H pylori has declined by 15.9% (95% CI, -20.5% to -11.3%) over the last 3 decades in adults, but not in children and adolescents. Significant reduction of H pylori prevalence was observed in adults in the Western Pacific, Southeast Asian, and African regions. However, H pylori prevalence was not significantly reduced in children and adolescents in any World Health Organization regions. The incidence of gastric cancer has decreased globally and in various countries where the prevalence of H pylori infection has declined. CONCLUSIONS: The global prevalence of H pylori infection has declined during the last 3 decades in adults, but not in children and adolescents. The results raised the hypothesis that the public health drive to reduce the prevalence of H pylori as a strategy to reduce the incidence of gastric cancer in the population should be confirmed in large-scale clinical trials.

Secular-Trend Analysis of the Incidence Rate of Lung Squamous Cell Carcinoma in Taiwan.

Lung cancer is the leading cause of cancer deaths worldwide, and squamous cell carcinoma (SQC) is Taiwan's second most common lung carcinoma histotype. This study aimed to investigate changes in the long-term trend of the SQC incidence rate in Taiwan. SQC cases between 1985 and 2019 were adopted from Taiwan's Cancer Registry System; the age-adjusted incidence rate was calculated using the World Standard Population in 2000. The long-term trends of the age, period, and birth cohort effect of SQC incidence rates were estimated using the SEER Age-Period-Cohort Web Tool. The results revealed that the incidence of lung carcinoma in Taiwan increased, while the incidence of SQC exhibited a slight decrease during this study period. The age rate ratio (ARR) of the incidence rate in men declined gradually, and the period effect changed more slowly for women than men. The cohort effect formed a bimodal curve. The annual percentage change results for women indicated that the ARR decreased from 1.652 (95% confidence interval (CI): 1.422, 1.9192) at 30 to 34 years to 0.559 (95% CI: 0.4988, 0.6265) at 75 to 79 years; the period effect decreased from 1.2204 (95% CI: 1.1148, 1.336) in 1995 to 1999 to 0.608 (95% CI: 0.5515, 0.6704) in 2015 to 2019, with a greater decline in the later period. The cohort effect was unimodal, with the SQC risk value peaking in the 1915 birth cohort and exhibiting a steady decline thereafter. The results of this study suggest that a decrease in the smoking rate may be the reason for the decline in the incidence of SQC, and we observed a similar trend between SQC and the smoking rate in men.