目的: 描述宁波市鄞州区常住居民炎症性肠病发病的分布特征，了解该地区炎症性肠病的疾病负担和发展趋势。方法: 采用回顾性队列设计，收集2010—2020年鄞州区全民健康信息平台的居民健康档案中所有常住居民的登记信息，利用电子病历随访其炎症性肠病就诊情况，设置1年洗脱期，以登记1年后首次诊断且以炎症性肠病为首要诊断的患者为新发病例。采用泊松分布估算炎症性肠病的发病密度及其95%置信区间(confidence interval, CI)。结果: 2011—2020年累计纳入鄞州区常住居民1 496 427人，其中男性729 996人(48.78%)，总随访人年8 081 030.82，中位随访人年5.41 [四分位距(interquartile range, IQR): 5.29]。研究期间共有1 217例炎症性肠病新发病例，男性(624例，51.27%)多于女性(593例，48.73%)，总发病密度为15.06/10万人年(95%CI: 14.23, 15.93)，其中溃疡性结肠炎1 106例(90.88%)，发病密度为13.69/10万人年(95%CI: 12.89, 14.52)；克罗恩病70例(5.75%)，发病密度为0.87/10万人年(95%CI: 0.68, 1.09)；未定型结肠炎41例(3.37%)，发病密度为0.51/10万人年(95%CI: 0.36, 0.69)。溃疡性结肠炎的中位发病年龄为50.82岁(IQR: 18.77)，发病年龄在45~49岁组占比最高(15.01%)；发病密度随年龄增长逐渐上升，45~49岁年龄组达到较高水平，随后略有上升，65~69岁年龄组发病密度最高，为25.44/10万人年(95%CI: 20.85, 30.75)，至75~79岁组发病密度迅速下降；克罗恩病的中位发病年龄为44.34岁(IQR: 33.41)，发病年龄在25~29岁组占比最高(12.86%)，由于克罗恩病新发病例数较少，年龄分布波动较大，青年和老年各有峰值。2011—2020年间，鄞州区炎症性肠病的发病密度在2011—2013年处于较低水平，2014—2016年呈迅速上升趋势，2016年达到峰值[24.62/10万人年(95%CI: 21.31, 28.30)]，2017—2020年略有下降。结论: 2011—2020年鄞州区炎症性肠病发病密度呈较高水平，医疗机构和卫生部门需重视其所带来的疾病负担。

Objective: To describe the distribution characteristics of inflammatory bowel disease among permanent residents in Yinzhou District, Ningbo City, and to understand the disease burden and development trend of inflammatory bowel disease in this area. Methods: Using the retrospective cohort design, we collected the registration information of all permanent residents in the residents' health files of the Yinzhou Regional Health Information Platform from 2010 to 2020, and used electronic medical records to follow up their inflammatory bowel disease visits. A one-year wash-out period was set, and the patients who were diagnosed with the primary diagnosis for the first time after one year of registration were re-garded as new cases. The incidence density and 95% confidence interval (CI) of inflammatory bowel disease were estimated by Poisson distribution. Results: From 2011 to 2020, a total of 1 496 427 permanent residents in Yinzhou District were included, of which 729 996 were male (48.78%). The total follow-up person-years were 8 081 030.82, and the median follow-up person-years were 5.41 [interquartile range (IQR): 5.29]. During the study period, there were 1 217 new cases of inflammatory bowel disease, of which males (624 cases, 51.27%) were more than females (593 cases, 48.73%). The total incidence density was 15.06/100 000 person-years (95%CI: 14.23, 15.93). Among all new cases, there were 1 106 cases (90.88%) of ulcerative colitis, with an incidence density of 13.69 per 100 000 person-years (95%CI: 12.89, 14.52); 70 cases (5.75%) of Crohn's disease, with an incidence density of 0.87 per 100 000 person-years (95%CI: 0.68, 1.09); and 41 cases (3.37%) of indeterminate colitis, with an incidence density of 0.51 per 100 000 person-years (95%CI: 0.36, 0.69). The median age of onset of ulcerative colitis was 50.82 years old (IQR: 18.77), with the highest proportion (15.01%) in the 45-49 years group. The incidence density of ulcerative colitis gradually increased with age, reaching a relatively high level in the 45-49 years group (20.53/100 000 person-years; 95%CI: 17.63, 23.78), followed by a slight increase. And the incidence density in the 65-69 years group was the highest (25.44/100 000 person-years; 95%CI: 20.85, 30.75), with a rapid decrease in the 75-79 years group. The median age of onset of Crohn's disease was 44.34 years (IQR: 33.41), with the highest proportion (12.86%) in the 25-29 years group. Due to the small number of new cases of Crohn's disease, the age distribution fluctuated greatly, with peaks both in young and old people. From 2011 to 2020, the incidence density of inflammatory bowel disease in Yinzhou District was at a low level from 2011 to 2013, and showed a rapid upward trend from 2014 to 2016, reaching a peak of 24.62 per 100 000 person-years in 2016 (95%CI: 21.31, 28.30), and slightly decreased in 2017—2020. Conclusion: The incidence density of inflammatory bowel disease in Yinzhou District from 2011 to 2020 was at a relatively high level, and medical institutions and health departments need to pay attention to the burden of disease caused by it.