No study to date has established the clinical features of long-duration type 1 diabetes in a non-Caucasian population. We identified people who survived ≥30 years with type 1 diabetes across China through a national program and performed the current study to establish the profile of this population.
Between 2015 and 2016, all of the registered subjects (n = 105) were contacted, and 95 of them completed the study visit. Demographic and socioeconomic data, body weight, height, and blood pressure were collected by study physicians, and blood and urine samples were collected locally and transported to a central laboratory.
Clinical characteristics were consistent with type 1 diabetes: mean (± SD) age at onset was 17.1 (± 8.6) years, and mean BMI was 22.48 (± 2.75) kg/m2. Mean LDL level was 2.87 (± 1.02) mg/dL, with only 12.6% of participants using statins (Table 1). Meanwhile, 42.9% of participants reported hypertension and 14.3% had cardiovascular disease. A high proportion of the participants remained free from diabetic nephropathy (65.9%), while the proportions reporting retinopathy and neuropathy were 67.9% and 60.7%, respectively. Among those with retinopathy, 50.0% had received laser therapy. Autoantibodies against GAD, IA-2, and zinc transporter 8 were detected in 17.1%, 5.7%, and 1.4% of the participants, respectively. BMI was significantly higher in the antibody-positive group.
Sociodemographic and clinical characteristics of participants with long-term type 1 diabetes in China
| . | All (n = 95) . | Plasma antibody negative (n = 56)* . | Plasma antibody positive (n = 13)* . |
|---|---|---|---|
| Age, years | 55.2 (10.4) | 55.3 (10.9) | 57.8 (9.7) |
| Age at diagnosis, years | 17.1 (8.6) | 16.9 (8.9) | 18.9 (8.0) |
| Diabetes duration, years | 37.3 (6.8) | 37.4 (6.9) | 37.9 (7.9) |
| Highest level of education, n (%)* | |||
| < University | 56 (57.1) | 24 (51.1) | 8 (64.0) |
| Junior university | 12 (12.2) | 6 (12.8) | 3 (12.0) |
| ≥ University | 16 (16.3) | 7 (14.9) | 2 (18.0) |
| Occupation, n (%)* | |||
| Nongovernment worker | 13 (13.3) | 7 (14.9) | 2 (12.0) |
| Government worker | 10 (10.2) | 3 (6.4) | 2 (14.0) |
| Student | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Farmer | 4 (4.1) | 3 (6.4) | 0 (0.0) |
| Retired/unemployed/never worked | 56 (84.7) | 24 (51.1) | 8 (64.0) |
| Marital status, n (%)* | |||
| Married/cohabitating | 62 (63.3) | 29 (61.7) | 6 (66.0) |
| Single/never married/widowed | 22 (21.4) | 8 (17.0) | 2 (28.0) |
| Medical insurance, n (%)* | |||
| Urban employee | 5 (5.1) | 3 (6.4) | 2 (4.0) |
| Urban resident | 59 (60.2) | 24 (51.1) | 35 (70.0) |
| New cooperative | 17 (17.3) | 9 (19.1) | 8 (16.0) |
| Other | 2 (2.0) | 0 (0.0) | 2 (4.0) |
| None | 1 (1.0) | 1 (2.1) | 0 (0.0) |
| Residency status, n (%)* | |||
| Urban | 67 (68.4) | 36 (61.7) | 9 (76.0) |
| Rural | 17 (17.3) | 11 (17.0) | 4 (18.0) |
| Daily insulin dosage, units* | 41.3 (14.7) | 40.3 (14.9) | 42.2 (14.6) |
| Statin usage, n (%) | 12 (12.6) | 7 (14.9) | 5 (10.9) |
| BMI, kg/m2* | 22.48 (2.75) | 21.86 (2.35) | 24.49 (3.50)† |
| SBP, mmHg* | 126.3 (18.7) | 124.9 (25.7) | 126.3 (18.7) |
| DBP, mmHg* | 72.6 (9.0) | 72.1 (13.2) | 72.6 (9.0) |
| HbA1c, %* | 6.87 (1.15) | 6.94 (1.14) | 6.87 (1.15) |
| Total cholesterol, mg/dL* | 5.16 (1.19) | 4.84 (1.35) | 5.16 (1.19) |
| HDL, mg/dL* | 1.56 (0.33) | 1.63 (0.49) | 1.56 (0.33) |
| LDL, mg/dL* | 2.87 (1.02) | 2.65 (1.12) | 2.87 (1.02) |
| Triglyceride, mg/dL* | 1.08 (0.50) | 1.11 (0.59) | 1.08 (0.50) |
| Creatinine, μmol/L* | 87.4 (3.2) | 89.6 (4.3) | 81.1 (5.6) |
| C-peptide ≥0.075 nmol/L, n (%)* | 14 (14.7) | 11 (19.6) | 3 (21.4) |
| Urinary Alb/Cr, mg/g, median (minimum, maximum)* | 9.88 (0.35, 5,557.8) | 8.29 (0.06, 8,759.4) | 9.88 (0.35, 5,557.8) |
| . | All (n = 95) . | Plasma antibody negative (n = 56)* . | Plasma antibody positive (n = 13)* . |
|---|---|---|---|
| Age, years | 55.2 (10.4) | 55.3 (10.9) | 57.8 (9.7) |
| Age at diagnosis, years | 17.1 (8.6) | 16.9 (8.9) | 18.9 (8.0) |
| Diabetes duration, years | 37.3 (6.8) | 37.4 (6.9) | 37.9 (7.9) |
| Highest level of education, n (%)* | |||
| < University | 56 (57.1) | 24 (51.1) | 8 (64.0) |
| Junior university | 12 (12.2) | 6 (12.8) | 3 (12.0) |
| ≥ University | 16 (16.3) | 7 (14.9) | 2 (18.0) |
| Occupation, n (%)* | |||
| Nongovernment worker | 13 (13.3) | 7 (14.9) | 2 (12.0) |
| Government worker | 10 (10.2) | 3 (6.4) | 2 (14.0) |
| Student | 0 (0.0) | 0 (0.0) | 0 (0.0) |
| Farmer | 4 (4.1) | 3 (6.4) | 0 (0.0) |
| Retired/unemployed/never worked | 56 (84.7) | 24 (51.1) | 8 (64.0) |
| Marital status, n (%)* | |||
| Married/cohabitating | 62 (63.3) | 29 (61.7) | 6 (66.0) |
| Single/never married/widowed | 22 (21.4) | 8 (17.0) | 2 (28.0) |
| Medical insurance, n (%)* | |||
| Urban employee | 5 (5.1) | 3 (6.4) | 2 (4.0) |
| Urban resident | 59 (60.2) | 24 (51.1) | 35 (70.0) |
| New cooperative | 17 (17.3) | 9 (19.1) | 8 (16.0) |
| Other | 2 (2.0) | 0 (0.0) | 2 (4.0) |
| None | 1 (1.0) | 1 (2.1) | 0 (0.0) |
| Residency status, n (%)* | |||
| Urban | 67 (68.4) | 36 (61.7) | 9 (76.0) |
| Rural | 17 (17.3) | 11 (17.0) | 4 (18.0) |
| Daily insulin dosage, units* | 41.3 (14.7) | 40.3 (14.9) | 42.2 (14.6) |
| Statin usage, n (%) | 12 (12.6) | 7 (14.9) | 5 (10.9) |
| BMI, kg/m2* | 22.48 (2.75) | 21.86 (2.35) | 24.49 (3.50)† |
| SBP, mmHg* | 126.3 (18.7) | 124.9 (25.7) | 126.3 (18.7) |
| DBP, mmHg* | 72.6 (9.0) | 72.1 (13.2) | 72.6 (9.0) |
| HbA1c, %* | 6.87 (1.15) | 6.94 (1.14) | 6.87 (1.15) |
| Total cholesterol, mg/dL* | 5.16 (1.19) | 4.84 (1.35) | 5.16 (1.19) |
| HDL, mg/dL* | 1.56 (0.33) | 1.63 (0.49) | 1.56 (0.33) |
| LDL, mg/dL* | 2.87 (1.02) | 2.65 (1.12) | 2.87 (1.02) |
| Triglyceride, mg/dL* | 1.08 (0.50) | 1.11 (0.59) | 1.08 (0.50) |
| Creatinine, μmol/L* | 87.4 (3.2) | 89.6 (4.3) | 81.1 (5.6) |
| C-peptide ≥0.075 nmol/L, n (%)* | 14 (14.7) | 11 (19.6) | 3 (21.4) |
| Urinary Alb/Cr, mg/g, median (minimum, maximum)* | 9.88 (0.35, 5,557.8) | 8.29 (0.06, 8,759.4) | 9.88 (0.35, 5,557.8) |
Data are mean (SD) unless otherwise indicated. Alb/Cr, albumin/creatinine; DBP, diastolic blood pressure; SBP, systolic blood pressure.
Eleven were missing for highest education level; 12 were missing for occupation; 11 were missing for marital status; 11 were missing for medical insurance; 11 were missing for residency status; 2 were missing for daily insulin dosage; 14 were missing for weight, height, and BMI; 17 were missing for SBP and DBP; 1 was missing for HbA1c; 1 was missing for total cholesterol, HDL, LDL, and triglyceride; 5 were missing for creatinine; 4 were missing for C-peptide; 11 were missing for urinary Alb/Cr; 26 were missing antibody status.
P < 0.05 from χ2 test and ANOVA test comparing antibody-positive and -negative groups.
One interesting observation in this population is the favorable lipid profile associated with longevity, which was also observed in the Golden Years Cohort and the Joslin 50-Year Medalist cohort (1,2). Relatively low BMI was consistent with the observation found in the Swedish National Diabetes Register (3). As in previous research (4), islet autoantibodies were still detectable in a large proportion of participants. The positive association between BMI and autoantibody status that was found for the first time might be partially explained by studies showing that higher BMI is associated with more residual β-cell function (5). Future mechanistic study will be needed for better understanding the reason for long-term survival in this population.
Article Information
Acknowledgments. The authors are indebted to the individuals whose participation made this study possible and to all the clinical physicians who helped with data and sample collection: Rongwen Bian, Jiangsu Provincial Hospital; Hanqing Cai, The Second Affiliated Hospital of Jilin University; Zhimei Deng, Heilongjiang Province Qiqihar Hospital; Hongjie Di, Jiangsu Integrated Traditional Chinese and Western Medicine Hospital; Yatao Ding, Yanghou Hongquan Hospital; Jingtao Dou, China PLA General Hospital; Bo Feng, Shanghai East Hospital; Xuhua Gao and Qidong Zheng, Zhejiang Province Yuhuan Hospital; Chunxiu Gong, Beijing Children’s Hospital; Xiaoju Guan, Shanxi Province Taiyuan Heping Hospital; Lixin Guo, Beijing Hospital; Ruiqing Guo, Hebei Province Cangzhou Second Hospital; Xiaohui Guo and Nan Gu, Peking University First Affiliated Hospital; Xu Hong, Beijing Friendship Hospital; Hui Hui, Hunan Province Binzhou Hospital; Qiuhe Ji, Xi’an Xijing Hospital; Jinhua Jiang, Yanbian Second Hospital; Hui Jin, Dongnan University Zhongda Hospital; Weihong Li, Shanxi Province Yangquan Hospital; Yuxia Li, Shanxi Province Yuncheng Tongde Hospital; Ziling Li, Neimenggu Baogang Hospital; Shaoda Lin and Kun Lin, Guangdong Province Shantou First Hospital; Chang Liu, Hunan Province Binzhou First Hospital; Hongfei Liu, Hunan Province Third Hospital; Changmei Liu, Binyi Hospital; Jie Liu, Shanxi Province People’s Hospital; Juming Lu, China PLA General Hospital; Weiping Lu, Jiangsu Province Huaian Hospital; Weiguang Luo, Shenyang Fourth Hospital; Li Mao, Jiangsu Province Huaian Hospital; Anhua Shao, Shanghai First Hospital; Yi Shen, Hebei Province Qinhuangdao First Hospital; Jianying Tang, Shanghai Third Hospital; Zhenghe Tang, Shandong Province Laigang Hospital; Chenggong Tian, Nanjing Gulou Hospital; Haoming Tian and Sheyu Li, Sichuan University Huaxi Hospital; Su Wang, Tianjing Fifth Hospital; Ying Wang, Jiangsu Province Yangzhou First Hospital; Feng Wei, Shandong Province Binzhou Hospital; Jianping Xiang, Hunan Province Huaihua First Hospital; Xinhua Xiao and Jianping Xu, Beijing Union Hospital; Zhangrong Xu, China PLA 306 Hospital; Bingquan Yang, Dongnan University Zhongda Hospital; Jianming Yang, Hubei Province Yichang First Hospital; Jie Yang, Shandong Province Taian Hospital; Sujie Yang, Shandong Luzhong Hospital; Tao Yang, Jiangsu Province People’s Hospital; Hong Yin, Gansu Province Lanzhou First Hospital; Xiaohua Yu, Liaoning Province Liaoyang Central Hospital; Jing Zhang, Shanxi Province Integrated Traditional Chinese and Western Medicine Hospital; Lei Zhang, Qingdao Diabetes Hospital; Qian Zhang, Guiyang Medical School Second Affiliated Hospital; Xiaokai Zhang, Fujian Province General Hospital; Ying Zhang, Guangzhou Medical School Third Affiliated Hospital; Qiu Zhang, Anhui Medical School First Affiliated Hospital; Meihua Zhao, Jiangsu Province Huaian First Hospital; Qian Zhao, Ningxia Province People’s Hospital; Hui Zheng, Tianjing Taida International Cardiovascular Hospital; Mao Zheng, Anhui Province General Hospital; Hong Zhong, Heilongjiang Province General Hospital; Jiaqiang Zhou, Sir Run Run Shaw Hospital; Qun Zhu, Nanjing Medical University Second Affiliated Hospital; and Benliang Zou, Xiyuan Hospital China Academy of Chinese Medical Sciences. The authors also thank Dr. Zhiguang Zhou and Dr. Gan Huang (Zhongnan University Xiangya Second Hospital) for their help with the autoantibody measurement and George Liang King (Harvard Joslin Diabetes Center) for his insightful suggestions on the manuscript.
Funding. This study was supported by the National Key R&D Program of China (2016YFC1304901, 2016YFC1305603), National High-tech R&D Program of China (863 Program) (2012AA02A509), and Beijing Science and Technology Committee Funding (D131100005313008).
Duality of Interest. No potential conflicts of interest relevant to this article were reported.
Author Contributions. W.L. and L.J. conceived and designed the study and drafted the manuscript, with key input from X.H. W.L. and Y.W. did the statistical analyses. S.G. played a key role in study design. Y.M. and S.Z. played key roles in recruitment of participants. X.G. contributed to generation of data. All authors provided critical input into revised versions of the manuscript. L.J. is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
