Individualised targets for insulin initiation in type 2 diabetes mellitus—the influence of physician and practice: a cross-sectional study in eight European countries

Abstract

Objectives To determine at what glycated haemoglobin (HbA1c) level physicians from eight European countries would initiate insulin in type 2 diabetes, which physician or practice related factors influenced this level and whether physicians would differentiate between a younger uncomplicated patient and an older patient with comorbidities.Design Cross-sectional study with data from the Guideline Adherence to Enhance Care study.Setting and participants 410 physicians from both primary and secondary care from Belgium, France, Germany, Italy, Ireland, Sweden, the Netherlands and the UK.Outcome measures Physicians were asked at which HbA1c level they would initiate insulin for a young, uncomplicated patient (vignette 1) and for an older, complicated patient (vignette 2). We evaluated differences in HbA1c levels between physicians from different countries using analysis of variance. To identify physician and practice related factors associated with HbA1c level at initiation of insulin, we performed multivariable linear regression. Multiple imputation was used to deal with missing data.Results In Germany, Ireland, Sweden, the Netherlands and the UK, the HbA1c levels for initiating insulin in vignette 2 (range: 60.0 to 66.0 mmol/mol; 7.6% to 8.2%) were higher than for vignette 1 (range: 57.2 to 64.2 mmol/mol; 7.4% to 8.0%). In multivariable analysis, the HbA1c level at which insulin was initiated only differed between countries (vignette 1): Dutch physicians initiated insulin at a lower HbA1c level compared with Belgium, France and the UK. No physician or practice factors were independently associated with HbA1c level at insulin initiation.Conclusions When deciding on individualised HbA1c targets for insulin initiation, physicians from five countries took patient’s age and comorbidity into account. The HbA1c level at which physicians would initiate insulin therapy differed between countries.