Date Published: April 22, 2019
Publisher: Public Library of Science
Author(s): Mukharram M. Bikbov, Rinat R. Fayzrakhmanov, Gyulli M. Kazakbaeva, Rinat M. Zainullin, Inga I. Arslangareeva, Timur R. Gilmanshin, Venera F. Salavatova, Nikolai A. Nikitin, Svetlana R. Mukhamadieva, Dilya F. Yakupova, Renat I. Khikmatullin, Artur F. Zaynetdinov, Yulia V. Uzianbaeva, Said K. Aminev, Ildar F. Nuriev, Jost B. Jonas, Iratxe Puebla.
Non-communicable chronic diseases have become the leading causes of mortality and disease burden worldwide. With information about the frequency of diabetes as a major non-communicable chronic disease in Russia being scarce, we assessed the prevalence of diabetes and its associated factors in a rural and urban population in Russia.
The Ural Eye and Medical Study is a population-based study in the city of Ufa/Russia and in villages in a distance of 65 km from Ufa. Inclusion criterion was an age of 40+ years. All study participants underwent a standardized interview and a detailed general examination. Diabetes mellitus was defined by a plasma glucose concentration ≥7.0 mmol/L or self-reported history of physician diagnosis of diabetes.
Out of a population of 7328 eligible individuals, 5899 individuals (2580 (43.7%) men) (participation rate:80.5%) participated (mean age:59.0±10.7 years (range:40–94 years)). Diabetes mellitus was present in 687 individuals (11.7%;95% confidence interval (CI):11.9,12.5). Awareness rate of having diabetes was 500/687 (72.8%;95%CI:69.0,76.0), with mean known duration of diabetes of 10.0±9.4 years. Known type 1 diabetes was present in 44 subjects and known type 2 diabetes in 358 subjects. Prevalence of undiagnosed diabetes was 3.2% (95%CI:2.7,3.6) in the study population. Among patients with diabetes, 59.1% (95%CI:55.4,62.8) received treatment for diabetes, among whom 237 (58.5%;95%CI:53.7,63.3) individuals had adequate glycemic control. In multivariable analysis, higher prevalence of diabetes mellitus was associated with older age (P<0.001; odds ratio (OR):1.03;95%CI:1.01,1.04), higher body mass index (P<0.001;OR:1.07;95%CI:1.04,1.10), lower prevalence of vigorous daily work (P = 0.002;OR0.68;95%CI:0.53,0.87), positive history of arterial hypertension (P = 0.03;OR:1.40;95%CI:1.03,1.89) and cardiovascular diseases (P = 0.001;OR:1.60;95%CI:1.21,2.13) including heart attacks (P = 0.01;OR:1.80;95%CI:1.15,2.81), higher serum concentration of triglycerides (P<0.001;OR:1.51;95%CI:1.30,1.75), higher systolic blood pressure (P = 0.01;OR:1.01;95%CI:1.01,1.02), higher number of meals taken daily (P<0.001;OR:1.46;95%CI:1.25,1.69), and non-Muslim religion (P = 0.02;OR:0.73;95%CI:0.56,0.94). In this ethnically mixed, urban and rural Russian population aged 40+ years, the awareness rate of diabetes (72.8%) was relatively high, while the diabetes prevalence (11.7%) was comparable with that of other countries such as China and the USA. Factors associated with higher diabetes prevalence were similar in Russia and these other countries and included older age, higher body mass index and higher serum concentration of triglycerides, lower prevalence of vigorous daily work, arterial hypertension and cardiovascular diseases.
Diabetes mellitus has become one of the most important causes of disability and death in all world regions. In the recent Global Burden of Diseases Study 2015, diabetes has climbed from position # 24 in 1990 through position #16 in 2005 to position #11 in 2015 in the ranking list of the most frequent causes of global DALYs (disability-adjusted life-years) for both sexes . In a parallel manner, diabetes besides ischemic heart disease and stroke was among the leading causes of years of life lost (YLLs) in most world regions . Despite the high importance of diabetes for public health and although Russia is by area the largest, and by population one of the most populous, countries worldwide, information about the prevalence of diabetes in Russia and factors associated with the occurrence of diabetes in Russia has remained scarce [3–5]. A large-scaled investigation on 26,620 adult Russians assessed the prevalence of diabetes, however, the recruitment occurred in highly frequented public areas and it was not purely population-based . Another Russian investigation on the prevalence of diabetes was performed in a selected relatively small study population in the Siberian region of Krasnoyarsk . Other studies examined the frequency of an impaired fasting glucose and the prevalence of the metabolic syndrome and on familial hypercholesterolemia in relatively small cohorts of Yakut adults in North-West Siberia [6,7]. In view of the scarcity of data on the prevalence of diabetes and its associated factors available for Russia and in view of the importance of diabetes, we therefore conducted this study to assess the prevalence of diabetes in a population in Russia and to explore associations between diabetes and other major risk factors. Since Russia includes many ethnicities, we chose as study area a region with a population consisting of Russians and other ethnic groups with different cultural background.
The Ural Eye and Medical Study (UEMS) is a population-based cross-sectional study performed in the urban region of Kirovskii in the city of Ufa and in villages of the rural region of the Karmaskalinsky District in a distance of 65 km from Ufa in direction to the Ural Mountains. It was conducted from 2015 to 2017. According to the Declaration of Helsinki, the Ethics Committee of the Academic Council of the Ufa Eye Research Institute approved the study and all participants gave informed written consent. The ethics committee confirmed that all methods were performed in accordance with the relevant guidelines and regulations. Inclusion criterion for the participation in the study was an age of 40+ years, with no exclusion criteria. The reasons to choose an age of 40+ years as inclusion criterion was that the prevalence of major disorders starts to increase beyond that age, so that with that age value the study population would include a sufficient number of patients affected by the disease, and a sufficient number of healthy control individuals. In addition, many population-based studies have chosen this age-limit as inclusion criterion, so that the results of the present study would easier to be compared with the observations made in previous investigations. The study has been described in detail previously [8–10]
The study included 5899 individuals (2580 (43.7%) men) out of a population of 7328 eligible individuals, with a participation rate of 80.5%. The non-participation of the eligible but non-participating individuals was due to the individuals´ decision not to participate. The mean age of the study population was 59.0 ± 10.7 years (median: 58 years; range: 40–94 years). The composition of the study population with respect to gender and age corresponded to the gender and age distribution in the Russian population according to the census carried out in 2010, with no significant difference between both populations (P = 0.25) (Table 2) . With respect to the ethnic composition, the percentage of the non-Russian groups was higher in the present study population than in the population of all Russia. For that reason, the statistical analysis was additionally performed separately for both groups, the Russian group and the non-Russian group. Mean body height was 164.8 ± 8.8 cm (median: 164 cm; range: 112–196 cm), mean body weight was 75.9 ± 14.6 kg (median: 75 kg; range: 31–170 kg), and mean body mass index was 27.9 ± 5.0 kg/m2 (median: 27.4 kg/m2; range: 13.96–60.96 kg/m2). Illiteracy (equivalent to level 0 or pre-primary education of the International Standard Classification of Education (ISCED) was present for 17 (0.3%) individuals, 104 (1.8%) participants had passed the fifth grade (equivalent to ISCED level I; primary education or first stage of basic education), 593 (10.1%) participants the 8th grade (equivalent to ISCED level II or lower secondary education), 659 (11.2%) participants the 10th grade (equivalent to ISCED level III or upper secondary education), and 782 (13.3%) individuals the 11th grade (equivalent to ISCED level IV or post-secondary non-tertiary education). Graduates (equivalent to ISCED level V or first stage of tertiary education) were 2052 (34.8%) individuals, and post graduates (equivalent to ISCED level VI or second stage of tertiary education) were 52 (0.9%) study participants. A specialized secondary education had been achieved by 1638 (27.8%) individuals.
In this population-based study in a typically ethically mixed urban and rural population of Russia, the prevalence of diabetes mellitus was 11.7% (95%CI: 11.89, 12.53) in the population aged 40+ years, with an awareness rate of 72.8% (95%CI: 69.0, 76.0). The prevalence of undiagnosed diabetes was 3.2% (95% CI: 2.7, 3.6): 3.6% (95% CI: 2.9, 4.4) in men and 2.8% (95% CI: 2.3, 3.4) in women. Among patients with diabetes, 59.1% (95% CI: 55.4, 62.8) received treatment for diabetes. Among those 406 diabetic individuals with diabetic therapy, 237 (58.5% (95%CI: 53.7, 63.3) individuals had a blood glucose concentration of lower than 7 mmol/L and were considered having adequate glycemic control. A higher prevalence of diabetes mellitus was associated with older age, higher body mass index, lower prevalence of vigorous daily work, positive history of arterial hypertension and including heart attacks, higher serum concentration of triglycerides, higher systolic blood pressure, higher number of meals taken daily, and non-Muslim religion (Tables 1–4).