目的：探索中国城市人群不同胃黏膜状态的胃癌发病风险。
方法：2014-2015年，在中国5个省份的7个城市招募人群进行问卷调查，利用问卷信息筛选出上消化道癌高危人群进行内镜检查，排除确诊结果为胃癌者，对剩余人群随访至2021年12月31日。根据检查结果，将人群分为胃黏膜正常、胃炎/溃疡/息肉（GUP）、萎缩性胃炎/肠上皮化生（AG/IM）、低级别上皮内瘤变（LGIN）、高级别上皮内瘤变（HGIN）五组。以胃黏膜正常组为对照，使用Cox比例风险模型分析各组人群的胃癌发病风险。
结果：纳入10396名研究对象，基线时胃黏膜正常、GUP、AG/IM、LGIN、HGIN人群分别为4898例、3741例、999例、737例、21例。经过随访（中位随访时间为6.77年），共发现37例胃癌新发病例，其中贲门癌5例、非贲门癌32例。胃癌发病密度（95%CI）为53.02（38.42 ~ 73.17）/10万人年，贲门癌为7.16（2.98 ~ 17.19）/10万人年，非贲门癌为45.84（32.42 ~ 64.83）/10万人年。各组人群胃癌发病密度（95%CI）分别为39.73（23.07 ~ 68.42）/10万人年、35.48（18.46 ~ 68.18）/10万人年、74.96（31.20 ~ 180.08）/10万人年、184.18（95.83 ~ 353.99）/10万人年、715.73（100.82 ~ 5081.17）/10万人年。以胃黏膜正常组为对照，GUP、AG/IM、LGIN、HGIN四组人群的胃癌发病风险比HR（95%CI）分别为0.90（0.38 ~ 2.10）、1.90（0.68 ~ 5.32）、4.62（1.97 ~ 10.80）、18.03（2.36 ~ 137.83），调整风险比aHR情况类似。男性人群胃癌发病密度（95%CI）为86.18（58.23 ~ 127.54）/10万人年，女性人群为29.43（16.71 ~ 51.81）/10万人年。以男性为对照组，女性的胃癌发病HR（95%CI）为0.34（0.17 ~ 0.68），aHR（95%CI）为0.63（0.23 ~ 1.74）。40-54岁人群胃癌发病密度（95%CI）为21.96（10.47 ~ 46.05）/10万人年，55-69岁人群为79.14（55.34 ~ 113.19）/10万人年。以40-54岁人群为对照组，55-69岁人群的胃癌发病HR（95%CI）为3.62（1.59 ~ 8.23），aHR（95%CI）为3.43（1.47 ~ 7.98）。
结论：在该人群中，各胃黏膜病变人群的占比随病变严重程度的增加而降低，贲门癌发病密度低于非贲门癌，胃癌发病风险随病变严重程度和年龄的增加而增加。

Objective: To investigate the gastric cancer risk among populations in urban China with different gastric mucosal status.
Methods: From 2014 to 2015, subjects were recruited in seven cities across five provinces in China for questionnaire surveys. Based on the questionnaire information, high-risk groups for upper gastrointestinal cancer were screened out for endoscopy. Those diagnosed with gastric cancer through the examination were excluded, and the remaining population was followed up until December 31, 2021. According to the examination results, the population was divided into five groups: normal gastric mucosa, gastritis/ulcer/polyp (GUP), atrophic gastritis/intestinal metaplasia (AG/IM), low-grade intraepithelial neoplasia (LGIN), and high-grade intraepithelial neoplasia (HGIN). Using the group with normal gastric mucosa as the reference, the Cox proportional hazards model was employed to analyze the risk of gastric cancer in each group.
Results: A total of 10,396 subjects were included in the study. At baseline, the numbers of individuals with normal gastric mucosa, GUP, AG/IM, LGIN, and HGIN were 4,898 cases, 3,741 cases, 999 cases, 737 cases, and 21 cases, respectively. After a follow-up period (with a median follow-up time of 6.77 years), 37 new cases of gastric cancer were identified, including 5 cases of cardiac gastric cancer and 32 cases of non-cardiac gastric cancer. The incidence density (95% CI) of gastric cancer was 53.02 (38.42 ~ 73.17) per 100,000 person-years. For cardia cancer, it was 7.16 (2.98 ~ 17.19) per 100,000 person-years, and for non-cardia cancer, it was 45.84 (32.42 ~ 64.83) per 100,000 person-years. The incidence densities (95% CI) of gastric cancer in the five groups were as follows: 39.73 (23.07 ~ 68.42) per 100,000 person-years, 35.48 (18.46 ~ 68.18) per 100,000 person-years, 74.96 (31.20 ~ 180.08) per 100,000 person-years, 184.18 (95.83 ~ 353.99) per 100,000 person-years, and 715.73 (100.82 ~ 5081.17) per 100,000 person-years. Using the normal gastric mucosa group as the reference, the hazard ratios (HRs) (95% CI) of gastric cancer for the GUP, AG/IM, LGIN, and HGIN groups were 0.90 (0.38 ~ 2.10), 1.90 (0.68 ~ 5.32), 4.62 (1.97 ~ 10.80), and 18.03 (2.36 ~ 137.83), respectively. The adjusted hazard ratios (aHRs) exhibited a similar pattern. The incidence density (95% CI) of gastric cancer was 86.18 (58.23 ~ 127.54) per 100,000 person-years in males and 29.43 (16.71 ~ 51.81) per 100,000 person-years in females. Using males as the reference, the HR (95% CI) of gastric cancer in females was 0.34 (0.17 ~ 0.68), and the aHR (95% CI) was 0.63 (0.23 ~ 1.74). The incidence density (95% CI) of gastric cancer was 21.96 (10.47 ~ 46.05) per 100,000 person-years in the 40-54 age group and 79.14 (55.34 ~ 113.19) per 100,000 person-years in the 55-69 age group. Using the 40-54 age group as the reference, the HR (95% CI) of gastric cancer in the 55-69 age group was 3.62 (1.59 ~ 8.23), and the aHR (95% CI) was 3.43 (1.47 ~ 7.98).
Conclusions: Within this population, the proportion of individuals with each gastric mucosal status gradually decreased as the severity of the gastric mucosal status increased. The incidence density of cardia cancer was lower than that of non-cardia gastric cancer. Moreover, the risk of gastric cancer increased with both the severity of gastric mucosal status and advancing age.