Incidence of type 1 diabetes mellitus in the Republic of Sakha (Yakutia) for 2018–2022

Type 1 diabetes mellitus (T1DM) is a socially significant disease with high disability and high mortality risk [1-3]. In the post-pandemic period, many regions of the Russian Federation have seen an increase in the incidence rate of T1DM, especially among children [4][5]. This phenomenon should certainly be studied. In this regard, regions with a centralized endocrinology service that provide the real scale of primary and general morbidity are of great interest. Herewith, the Republic of Sakha (Yakutia) can become a pilot region for conducting clinical and epidemiological studies, monitoring the epidemiological situation, and developing functional medical and organizational measures.

Materials and methods

The research presents a retrospective analysis of the primary and general incidence rate of T1DM in the Republic of Sakha (Yakutia) based on data from the regional registry and information from the Yakut Republican Information and Analytical Center for 2018–2022.

Results

According to the regional registry, in the Republic of Sakha (Yakutia) at the end of 2022, a total of 969 people were registered with the T1DM diagnosis, including 46 children, 29 adolescents, and 894 adults. The prevalence of T1DM in the Republic of Sakha (Yakutia) is 97.67 per 100,000 of the population.

The average age of patients with T1DM is 39.8 years. The gender distribution of patients with T1DM is as follows: 52% of men and 48% of women. The average life expectancy of patients with T1DM is 49.7 years. The average duration of the disease from the onset of T1DM is 12.4 years, with a disease duration of 10 years or more in 61.5% of patients (Table 1).

Dynamics of incidence of T1DM in the adult population

In dynamics from 2018 to 2022, the overall incidence rate of T1DM in the adult population in the Republic of Sakha (Yakutia) decreased by 15.5% and amounted to 263.6 per 100,000 adult population (2018 – 311.9). The primary incidence rate of T1DM in the adult population decreased by 1.3% and amounted to 7.9 per 100,000 adult population (2018 – 8.0) (Table 2).

When analyzing the overall incidence rate of T1DM by districts of the republic, it was revealed that an increase in the overall incidence rate of the adult population of the Republic of Sakha (Yakutia) was observed in eight (23.5%) districts: Ust-Maisky (6.7 times from 89.6 to 596.6 per 100,000 adult population), Oleneksky (3.4 times from 187.8 to 638.9), Srednekolymsky (3.2 times from 39.4 to 124.4), Nyurbinsky (by 42.6% from 44.1 to 62.9), and Megino-Kangalassky (by 41.6% from 86.8 to 122.9).

A decrease in the overall incidence rate of T1DM was observed in the city of Yakutsk (by 21.2% from 403.8 to 318.3 per 100,000 adult population) and 22 (64.7%) districts, among which the highest growth rates were in the following ones: Allaikhovsky (7 times from 369.2 to 52.5), Kobyaysky (4.9 times from 280.1 to 57.1), Bulunsky (4.1 times from 65.9 to 16.1), Gorny (3.3 times from 582.2 to 174.3), and Abyysky (2.5 times from 350.0 to 139.7).

In 2022, the overall incidence rate of T1DM in the adult population in the city of Yakutsk (318.3) and 7 (20.6%) districts exceeded the average values ​​for the republic, of which the maximum level was observed in Oleneksky (638.9), Ust-Maisky (596.6), Tomponsky (538.5), Mirninsky (463.6), and Aldansky (421.0) districts.

In 23 (67.6%) districts, the overall incidence rate in 2022 did not exceed the national values, while the minimum level was recorded in Bulunsky (16.1), Verkhnekolymsky (33.1), Verkhnevilyuysky (49.9), Eveno-Bytantaysky (50.5), and Allaikhovsky (52.5) ​​districts.

During the analyzed period, an increase in the primary incidence rate of T1DM in the adult population of the Republic of Sakha (Yakutia) was noted in three (8.8%) districts: Ust-Aldansky (2 times from 7.2 to 14.5 per 100,000 adult population), Tomponsky (by 25.9% from 42.8 to 53.9), and Neryungri (by 15.9% from 8.8 to 10.2).

A decrease in the primary incidence rate of T1DM was observed in the city of Yakutsk (by 32.6% from 4.3 to 2.9) and six (17.6%) districts: Gorny (2 times from 75.9 to 37.3), Suntarsky (2 times from 12.9 to 6.4), Vilyuysky (2 times from 11.8 to 5.9), Aldansky (by 45.7% from 30.0 to 16.3), Olekminsky (by 1.8% from 5.5 to 5.4), and Mirny (by 1.6% from 18.6 to 18.3).

In 2022, the primary incidence rate of T1DM in the adult population in 11 (32.4%) districts exceeded the average values ​​for the republic, of which the maximum level was observed in Srednekolymsky (83.0), Tomponsky (53.9), Oleneksky (37.6), Gorny (37.3), and Abyysky (34.9) districts.

In the city of Yakutsk (2.9) and five (14.7%) districts, the indicator in 2022 did not exceed the republican values ​​(Olyokminsky (5.4), Vilyuysky (5.9), Nyurbinsky (6.3), Suntarsky (6.4), and Verkhnevilyuysky (7.1) districts).

Dynamics of incidence of T1DM in children

In dynamics from 2018 to 2022, the overall incidence rate of T1DM among children increased by 43.6% and amounted to 141.3 per 100,000 children (2018 – 98.4). The primary incidence rate of T1DM among children increased by 2.5 times and amounted to 25.7 per 100,000 children (2018 – 10.2) (Table 3).

During the research period, when analyzing by districts of the republic, an increase in the overall morbidity of the child population was noted in the city of Yakutsk (by 92.5% from 110.4 to 212.5) and 17 (50%) districts, of which the morbidity rate was faster in Kobyaisky (5.9 times from 26.5 to 157.3 per 100,000 children), Nyurbinsky (2.6 times from 25.1 to 64.4), Khangalassky (2.3 times from 114.3 to 258.6), Oymyakonsky (2 times from 50.9 to 103.0), and Anabarsky (96.3% from 80.5 to 158.0) districts.

A decrease in the indicator was observed in 10 (29.4%) districts of the republic; among them, a significant decrease was in the following ones: Bulunsky (4.1 times from 352.7 to 87.0), Amginsky (3.3 times from 178.7 to 54.9), Zhigansky (2.1 times from 141.5 to 68.4), Namsky (by 39.2% from 63.0 to 38.3), and Olekminsky (by 26.7% from 46.1 to 33.8).

In 2022, the overall incidence rate of T1DM in children in the city of Yakutsk (212.5) and six (17.6%) districts exceeded the average values ​​for the republic: in Khangalassky (258.6), Neryungri (251.7), Abyysky (196.7), Mirny (158.9), and Anabarsky (158.0).

In 23 (67.6%) districts, the indicator in 2022 did not exceed the national values, while the minimum level was recorded in Gorny (23.8), Churapchinsky (28.9), Olekminsky (33.8), Namsky (38.3), and Srednekolymsky (41.4) districts.

During the analyzed period, an increase in the primary morbidity rate of the child population of the Republic of Sakha (Yakutia) was noted in the city of Yakutsk (3.1 times from 14.0 to 43.2) and six (17.6%) districts: Mirninsky (2.6 times from 10.9 to 28.4 per 100,000 children’s population), Neryungrinsky (2 times from 30.1 to 61.4), Megino-Kangalassky (by 94.9% from 9.9 to 19.3), Olekminsky (by 9.7% from 15.4 to 16.9), Lensky (by 2.7% from 11.0 to 11.3), and  Verkhnevilyuysky (by 1.4% from 13.9 to 14.1) .

In 2022, the primary incidence rate of T1DM in children in the city of Yakutsk (43.2) and seven (20.6%) districts exceeded the average values ​​for the republic, of which the maximum level was observed in Eveno-Bytantaysky (110.1), Neryungri (61.4), Oymyakonsky (51.5), Srednekolymsky (41.4), and Khangalassky (33.7) districts.

In five (14.7%) districts, the primary incidence rate of T1DM in 2022 did not exceed the national values ​​(in Lensky (11.3), Verkhnevilyuysky (14.1), Olekminsky (16.9), Amginsky (18.3), and Megino-Kangalassky (19.3)) (Table 3).

The prevalence of complications induced by T1DM in the Republic of Sakha (Yakutia) as a percentage, according to the DM registry, was as follows: diabetic retinopathy – 20.2%, diabetic nephropathy – 8.3%, and diabetic neuropathy –18.1%.

The structure of hypoglycemic therapy, according to the regional DM registry, reflected the following: 90.57% of patients were on therapy with insulin analogues, 4.96% received genetically engineered human insulin, 4.47% received insulin analogues and genetically engineered human insulin (Table 4).

Conclusion

According to the regional registry, in the Republic of Sakha (Yakutia), T1DM mainly affects young people: the average age is 39.86 years, the average life expectancy of patients with T1DM is 49.67 years, which determines the social significance of the disease. In the dynamics from 2018 to 2022, there was a downward trend in the overall and primary incidence rate of T1DM in the adult population of the Republic of Sakha (Yakutia). However, the epidemiological picture of morbidity in the child population was completely opposite. Thus, in the dynamics from 2018 to 2022, a sharp increase in the overall and primary incidence rate of T1DM was observed in the child population in the Republic of Sakha (Yakutia) (the highest jump was in 2021–2022), and the primary incidence rate had increased by almost 2 times. In the future, this will lead to an increase in the overall incidence rate of T1DM in the adult population in the Republic of Sakha (Yakutia). The data of a retrospective analysis of the clinical and epidemiological characteristics of T1DM will help to define a concept for improving the endocrinology service in the Republic of Sakha (Yakutia).