Barriers towards insulin therapy in type 2 diabetic patients: results of an observational longitudinal study

BACKGROUND: The course of barriers towards insulin therapy was analysed in three different groups of type 2 diabetic patients. This observational longitudinal study surveyed a three-month follow-up. METHODS: Participants in this study totalled 130 type 2 diabetic patients. The first subgroup was on insulin therapy at baseline (group 1: n = 57, age 55.6 ± 8.7 yrs, disease duration 12.7 ± 7.2 yrs, HbA1c 8.5 ± 1.6%) and remained on insulin at follow-up. Of an initial 73 insulin-naïve patients, 44 were switched to insulin therapy (group 2: age 58.1 ± 6.8 yrs, disease duration 7.7 ± 5.0 yrs, HbA1c 9.1 ± 1.7%) and 29 patients remained on an oral regimen (group 3: age 52.7 ± 10.7 yrs, disease duration 5.3 ± 4.6 yrs, HbA1c 8.3 ± 1.4%). Barriers towards insulin therapy were measured using the Insulin Treatment Appraisal Scale (ITAS). As generic instruments of health related quality of life patients completed also the Problem Areas of Diabetes Questionnaire (PAID), the WHO-5 Well-Being Scale (WHO-5), the Centre for Epidemiologic Studies Depression Scale (CES-D) and the Trait Version of the State Trait Anxiety Inventory (STAI) at baseline and at three-month follow-up. RESULTS: At the three-month follow-up, HbA1c had improved in all three groups (7.7 ± 1.2% vs. 7.1 ± 1.1% vs. 6.7 ± 0.8%). The course of negative appraisal of insulin therapy was significantly different in the three groups (p > .003): the ITAS score increased in patients remained on oral antidiabetic drugs (51.2 ± 12.2 to 53.6 ± 12.3), whereas it decreased in patients switched to insulin therapy (49.2 ± 9.8 to 46.2 ± 9.9) or remained on insulin treatment (45.8 ± 8.3 to 44.5 ± 8.0). Diabetes-related distress, trait anxiety, and well-being, showed a similar course in all three groups. The depression score improved significantly in patients switched to insulin treatment compared with patients remaining on insulin therapy. CONCLUSIONS: In summary, this study suggests that a negative appraisal of insulin treatment is modifiable by the initiation of insulin therapy. This finding indicates that barriers to insulin are a rather temporary than a stable phenomenon.