Clinical characteristics and management of type 1 diabetes in Spain. The SED1 study

To determine the sociodemographic and clinical profile of a representative sample of people with type 1 diabetes mellitus (DM1) in Spain and identify factors associated with glycemic control.

A cross-sectional observational study was carried out in adults and children with DM1 treated in 75 Spanish public hospitals, geographically distributed in order to be representative of the Spanish population. Within each center, the patients were included on a consecutive basis as they visited the clinic. They were interviewed, and their clinical histories were reviewed. A descriptive statistical analysis was made, and factors associated with HbA_1c were analysed using multivariate linear regression analysis.

A total of 647 patients were included: 55.3% females, aged 36.6 ± 14.4 years, 97.2% Caucasians, BMI 24.7 ± 4.4 kg/m² (12.1% ≥ 30 kg/m²), and 74.0% had secondary / university education. A total of 20.2% were active smokers. The mean time from the diagnosis of DM1 was 17.9 ± 12.0 years. A total of 48.7% presented comorbidities: 19.3% retinopathy and 16.4% hypothyroidism. As regards treatment for DM1, 76.5% received basal-bolus insulin therapy and 20.7% continuous subcutaneous insulin infusion (CSII); 51.0% of the patients used an insulin/carbohydrate ratio (ICR), with 4.6 ± 1.6 self-monitored capillary blood glucose (SMCBG) measurements a day, and 24.8% used continuous glucose monitoring (CGM). The mean HbA_1c value was 7.6 ± 1.1% (30% below 7%). Metabolic control improved (lower HbA_1c) with more daily SMCBG (B = -0.053; p = 0.009), a higher educational level (B = 0.461; P < 0.001), greater number of hypoglycemia episodes (B = -0.253; P = 0.018) and carbohydrate counting (B = -0.190; P = 0.048), and worsened the longer the duration of the disease (B = 0.010; P = 0.010), higher total dose of insulin (B = 0.010; P < 0.0001), poorer adherence to diet (B = 0.650; P < 0.0001) and a family history of DM (B = -0.233; P = 0.007).

The management of patients with DM1 in Spain, as well as the treatment they receive, is similar to that seen in other Western countries. Blood glucose control is associated with educational level, disease duration, and the characteristics of treatment and self-care.