Background: New classes of antidiabetic medications have been introduced, but details of their use are not well known. The aim was to assess prescription patterns and dosing for insulin glargine (market launch: 6/2000) in primary care patients.
Methods: Computerized data on prescriptions (Disease Analyzer, 6/1999 to 8/2003) from 277 general and internal medicine practices throughout Germany were analysed (67,402 diabetic patients; 340 incident glargine (age: 67+/-12 years) and 378 incident NPH users (66+/-11 years).
Results: Diabetes prevalence in the practices increased over the three-year period (5.1% to 6.2%). The highest increase was observed for insulin treated patients (+29%), followed by diet (+21%) and oral antidiabetics (+19%). Premixed insulin (short-acting insulin and NPH) remained constant as largest insulin group. A continuous increase of short-acting insulin analogues was found (+70%). Long-acting insulin analogues (glargine) increased threefold. Glargine was more often prescribed in combination with oral antidiabetics than NPH (76% vs 49%; p<0.05). Only about a quarter received short-acting insulin (NPH: 61%; p<0.05). The cumulative annual dose was higher among NPH users (geometric mean; NPH: 7971 IU; glargine: 5719 IU) (p<0.01), which persisted after adjusting for age, sex, and morbidity (p<0.01).
Conclusions: Diabetes prevalence continuously increased in German primary care practices from 1999 to 2003. The largest increase was found for insulin treatment, in particular, for short and long-acting insulin analogues. Insulin glargine was more often prescribed in combination with oral agents, whereas NPH insulin was more frequently prescribed with short-acting insulin, indicating different prescription patterns in primary care.