Insulin glargine is a modified basal insulin analog that has been recently introduced, and following guidance from the National Institute for Clinical Excellence (NICE), it is now widely available in the U.K. (1). Studies in type 1 diabetes demonstrate that compared with NPH insulin, fasting blood glucose and hypoglycemic episodes are reduced and patient satisfaction is improved (2–7). To confirm whether these reported benefits are also achieved in routine clinical practice, we conducted a prospective audit of patients attending our diabetes clinic practice transferring to insulin glargine.
There were 83 patients with type 1 diabetes on multiple daily injection regimes who were transferred from NPH insulin to insulin glargine between July and November 2002. Indications for transfer were nocturnal hypoglycemia, morning fasting hyperglycemia, the use of two NPH injections, or patient request. Patient details, including glycemic control (glucose concentrations and HbA1c levels), were recorded. Patients completed a questionnaire on the frequency of hypoglycemia (requiring corrective action by patient) over the preceding month and severe hypoglycemic episodes (requiring assistance from a third party) over the 3 months preceding the initiation of insulin glargine therapy. Patient assessments on quality of life and well-being (Diabetes Treatment Satisfaction Questionnaire and Well-Being Questionnaire 28) (8,9) were also performed. Patients were reassessed after receiving insulin glargine for 3 months.
Morning blood glucose concentrations and HbA1c levels fell significantly, from 9.63 ± 0.44 to 7.15 ± 0.28 mmol/l (P < 0.001) and from 8.24 ± 0.16 to 7.86 ± 0.11% (P = 0.006), respectively. Total hypoglycemic episodes remained unchanged after transferral to insulin glargine. The number of severe hypoglycemic episodes was not statistically significantly different after transfer to glargine from baseline values (from 15 to 7) (P = 0.077). Aggregate scores for the Diabetes Treatment Satisfaction Questionnaire, which reflect satisfaction with treatment, improved from 23.5 (0.68) to 28 (0.67) (P < 0.001), whereas the score for unacceptably high blood glucose values fell from 3.53 (0.16) to 2.83 (0.17) (P = 0.002) with no significant change for unacceptably low blood glucose values (from 2.43 [0.16] to 2.11 [0.14]) (P = 0.07). The scores for the Well-Being Questionnaire 28 show significant improvements in patient-reported energy levels (P < 0.001), diabetes-specific well-being (P = 0.044), and total well-being (P = 0.001), with significant reductions in diabetes-related stress (P = 0.014).
Our results confirm that people with type 1 diabetes on a multiple daily insulin injection regime who transfer to insulin glargine from isophane insulin have a significant fall in their morning blood glucose concentrations and HbA1c levels as well as significant improvements in satisfaction with their treatment and subjective well-being. The use of insulin glargine appears to be advantageous for some patients with type 1 diabetes.