Intensive or conventional insulin therapy in type 2 diabetic patients? A population-based study on metabolic control and quality of life (The JEVIN-trial)

Summary

Long-term micro- and macrovascular complications cause major morbidity and mortality in patients with type 2 diabetes mellitus. Up to the present it is not clear whether intensified or conventional insulin treatment is more effective to keep blood glucose concentrations close to the normal range. In the present trial 90% (n = 117) of all insulin-treated type 2 diabetic patients aged 16 to 60 years and living in the city of Jena (100,247 inhabitants), Thuringia, Germany were examined. Fourty patients (34%) were on intensive insulin therapy (ICT, ≥ 2 injections of normal- and ≥ 1 injection of NPH-/mixed-insulin/day, ≥ 1 insulin-dose adjustments/ week, ≥ 2 blood-glucose self-tests/day) and 77 patients (66%) were on conventional insulin therapy (CIT). Patients with ICT had more injections/d (4.3 ± 0.7 vs CIT 2.4 ± 0.7, p < 0.001), more insulin-dose adjustments/week ≤ 11.5 ± 8.2 vs 2.2 ± 5.2, p < 0.001) and more blood-glucose self-tests/week (25.2 ± 5.7 vs 9.6 ± 8.8, p < 0.001). Patients with ICT had higher insulin doses (0.71 ± 0.32 vs 0.47 ± 0.2 IU/kg body wt/d, p < 0.001), were younger (50.5 ± 6.7 vs 54.0 ± 5.9 years, p = 0.004) and they had a non-significant tendency to a better HbAlc (8.7 ± 2.2 vs 9.2 ± 2.0%, p = 0.23, HPLC, Diamat^®, normal range 4.4–5,9%). There was a negative correlation between HbAlc and the frequency of blood-glucose self-tests/week (r = −0.23, p = 0.019) and the number of insulindose adjustments/week (r = −0.33, p < 0.001). There were no differences between the groups as regards body-mass index (29.7 ± 4.9 vs 28.0 ± 4.5 kg/m², p = 0.06), diabetes duration (12.3 ± 6.9 vs 12.2 ± 7.5 years, p = 0.96), duration of insulin therapy (4.2 ± 3.5 versus 4.5 ± 4.8 years, p = 0.67), incidence of acute complications (severe hypoglycaemia, diabetic coma), prevalence of retino-, nephro- and neuropathy (assessed according to Young et al.) and education or socio-economic factors. Also, in respect of quality of life and treatment satisfaction, assessed with standardized questionnaires according to Bradley et al. and Lewis et al., there were no differences between the two groups.

In conclusion, in type 2 diabetic patients, ICT seems to be indicated in a second step in “problem-patients” with bad metabolic control under CIT and/or individual's need for more flexibility. Perhaps, in these patients ICT leads to an improvement in the quality of metabolic control.

Key-Word

Population-based study, type 2 diabetic patients, intensified insulin therapy - conventional insulin therapy - HbAlc - acute and long-term complications