Type 1 diabetes mellitus (T1DM) predominantly affects adolescents, drawing substantial research focus. Conversely, older adults with T1DM receive relatively little attention and research. Consequently, disease burden data for this population are scarce and urgently require filling.

To assess the disease burden and projected trends of T1DM among the elderly (age≥60 years) from 1990 to 2021, thereby providing essential evidence for public health decision-making.

Data on the incidence and disability-adjusted life years (DALYs) associated with T1DM in the elderly were extracted from the Global Burden of Disease (GBD) 2021 database from 1990 to 2021, focusing on globally, China, and five sociodemographic index (SDI) regions. Taking the GBD 2021 standard population as the reference, age-standardized incidence and DALY rates for elderly individuals with T1DM were calculated based on the direct standardization method. The trend of disease burden was analyzed via Joinpoint regression, with results reported as average annual percent change (AAPC). Subgroup analyses stratified the disease burden by age and sex, respectively. Additionally, a three-factor decomposition method was employed to dissect the relative influences of aging, population growth, and epidemiological change on the shifts in disease burden. Finally, a Bayesian model was utilized to forecast the disease burden of elderly T1DM from 2022 to 2040.

In 2021, the global and Chinese incidence of T1DM stood at 42 330 and 3 049 cases, respectively, representing increases of 199.47% and 427.50% compared to 1990. The total DALYs of the elderly T1DM reached 659 117 person-years globally and 57 663 person-years in China in 2021, marking increases of 91.80% and 78.25%, respectively, since 1990. Age-standardized DALYs rate exhibited a downward trend globally and within China from 1990 to 2021, with statistically significant differences (P<0.001). The proportion of T1DM incidence cases was highest in the 60-64 age group globally, in China, and across the five SDI stratified regions. The proportion of incidence cases in Chinese 60-64 age group (27.91%) fell between the high-middle SDI region (26.01%) and the middle SDI region (30.26%), but the proportion of DALYs among Chinese T1DM patients in the 60-64 age group (24.06%) was lower than that of all other regions. Notably, individuals aged 60-69 years constituted 53.51% of all elderly T1DM patients in China, and accounting for 55.25% of total DALYs. Population growth emerged as the primary contributing factor, responsible for 58.34% of the increase in T1DM incidence among the elderly in China. Furthermore, it was identified as the decisive factor driving DALYs increases, contributing to 178.96%. Projections indicate a continued rise in both incidence and DALYs for elderly T1DM patients globally and in China from 2022 to 2040, with a more gradual change in DALYs observed among Chinese women compared to men.

The incidence of T1DM and the associated DALYs burden in the elderly remain substantially high both globally and in China. This underscores the urgent need for the formulation and implementation of more scientifically informed and effective public health policies and clinical intervention strategies to address this pressing health challenge.

1型糖尿病（T1DM）好发于青少年群体，这使得研究重点多集中于此，对老年T1DM的关注与研究相对不足，导致这一群体的疾病负担数据存在一定空白，亟待填补。

分析1990—2021年老年1型糖尿病的疾病负担和未来趋势，为公共卫生决策提供参考。

提取全球疾病负担（GBD）2021数据库中1990—2021年全球、中国及5个社会人口学指数（SDI）地区老年（年龄≥60岁）T1DM的发病和伤残调整生命年（DALYs）数据。以GBD 2021标准人口为参照，采用直接标准化法计算老年T1DM人群的年龄标准化发病率和年龄标准化DALYs率。疾病负担的趋势改变采用Joinpoint回归进行分析，结果以平均年度变化百分比（AAPC）表示。基于患者年龄和性别进行疾病负担的亚组分析，采用三因素分解方法分析老龄化、人口增长和流行病学改变3个因素对疾病负担变化的相对影响。使用贝叶斯模型预测2022—2040年老年T1DM的疾病负担趋势。

2021年全球、中国老年T1DM总体发病数分别为42 330人和3 049人，较1990年分别增加了199.47%和427.50%。2021年全球、中国老年T1DM总体DALYs分别为659 117人年和57 663人年，较1990年分别增加了91.80%和78.25%。全球、中国老年T1DM患者年龄标准化DALYs率均呈下降趋势，差异有统计学意义（P<0.001）。1990—2021年全球、中国、5个SDI分层地区老年T1DM患者发病数占比最高的是60~64岁组。中国60~64岁组患者的发病数占比（27.91%）介于高-中SDI区（26.01%）和中SDI地区（30.26%）之间，但中国60~64岁T1DM患者的DALYs占比（24.06%）却低于其他所有地区。此外，中国60~69岁患者发病数占其全部老年患者的53.51%，DALYs占其全部老年患者的55.25%。导致中国老年T1DM发病数增加的主要影响因素是人口增长，贡献度为58.34%。人口增长也是中国老年T1DM患者DALYs增加的决定性因素，贡献度高达178.96%。预计2022—2040年全球与中国老年T1DM患者总体、男性和女性的发病数和DALYs将呈上升趋势，且中国女性T1DM患者的DALYs改变趋势较男性更加平缓。

全球和中国老年T1DM的发病和DALYs负担仍然沉重，迫切需要进一步制定和实施更加科学、有效的公共卫生政策和临床干预策略，以积极应对这一严重的健康挑战。