Trend of body mass index and its impact on glycemic control in Finnish patients with type 2 diabetes

Abstract Background Obesity prevalence has increased in Finland and is prevalent in patients with type 2 diabetes (T2D). Understanding the trend in body mass index (BMI) and its impact on glycemic control helps in the assessment of treatment strategies for T2D. We aimed to investigate the current trend in BMI among Finnish patients with T2D and the glycated hemoglobin (HbA1c) control across different BMI categories. Methods Regional data on electronic health records (EHRs) covering all public health care in North Karelia, Finland, were used. Patients with T2D (ICD-10 code E11) in 2012-2022 were identified from EHRs. In each study year, patients with ≥1 measurement of BMI and HbA1c were included in data analysis. Generalized estimating equations regression analyses were performed to evaluate the trends. Results The annual number of patients in the analyses ranged from 5149 to 10216 in 2012-2022. The unadjusted mean BMI remained stable. However, an increasing trend in BMI was observed in the age-adjusted model and remained unchanged with further adjustment for sex, duration of diabetes, and antidiabetic medication use, reflecting the aging of the patient population and lower BMI in aged patients. Patients with higher BMI had higher HbA1c levels in 2012-2022. The increasing trends in HbA1c over time were observed across different BMI categories (except for the obsess class III) accounting for age, sex, and duration of diabetes. However, a decreasing trend in HbA1c was found in the obese class III category with further adjustment for antidiabetic medication use, along with the highest usage rates of the new antidiabetic medications during the follow-up. Conclusions Our findings suggest that weight management requires increased attention in Finnish patients with T2D and is also important for better glycemic control. Multimodal treatment, including effective lifestyle counseling, self-care support, and medication management, is needed. Key messages • More attention and resources are needed to achieve optimal weight control. • Weight management could aid in better glycemic control.