Quality of life following a change in therapy for diabetes mellitus

The study objective was to evaluate and compare quality-of-life (QOL) parameters between patients with type 2 (non-insulin-dependent) diabetes mellitus who changed therapy from an oral hypoglycaemic agent (OHA) to insulin and those who remained on an OHA.

The World Health Organization Quality of Life Questionnaire (WHOQOL) was used to assess quality of life among 2 groups of patients with type 2 diabetes mellitus at baseline and after a 2-month follow-up period.

The study was conducted in the outpatient department of the Vuk Vrhovac Clinic, a referral centre for registration, treatment and follow-up of patients with diabetes mellitus in Zagreb, Croatia.

32 consecutively recruited patients with type 2 diabetes mellitus who were switched from an OHA to insulin therapy (group 1) were compared with 28 patients who remained on OHA (group 2) with respect to QOL issues. The patient groups were comparable in terms of gender, age, duration of disease, education and family status. However, patients in group 1 had glycosylated haemoglobin (HbA1c) values greater than 9.5% on average during a period of approximately 6 months, which was the criterion used for switching to insulin therapy.

At baseline, various QOL ratings were higher among patients in group 2 than group 1, indicating better quality of life with respect to overall quality of life (t = -2.31, p = 0.03), physical health (t = -2.36, p = 0.02), psychological state (t = -2.01, p = 0.05) and level of independence (t = -2.75, p = 0.001), while no differences were found between groups with respect to the social domain, personal beliefs and environmental QOL aspects. After the follow-up period, the groups were comparable in all QOL aspects other than overall quality of life (t = -2.18, p = 0.03) and level of independence (t = -3.49, p = 0.001), both of which remained higher for patients in group 2. No changes in QOL parameters were detected within group 2 from baseline to the end of the 2-month follow-up period, whereas patients in group 1 showed significant improvement in psychological QOL determinants (t = -2.14, p = 0.04).

Results of the study indicate that introducing insulin therapy in patients with type 2 diabetes mellitus and sustained elevated HbA1c levels might positively affect their quality of life.