OBJECTIVES: To compare the impact of starting either insulin glargine once-daily or insulin detemir twice-daily on multiple dimensions of QOL in patients with type 2 diabetes inadequately controlled on OGLDs. METHODS: This study was part of a 24-week, multinational, randomised trial in which 964 insulin-naïve patients, aged 40-75 years, with inadequately controlled type 2 diabetes (HbA1c 7.0-10.5%) were randomised to glargine once-daily or detemir twice-daily. For both insulins the dose was titrated every 2 days by 2 U to obtain fasting plasma glucose <5.6 mmol/l. For detemir, there also was a pre-dinner target <5.6 mmol/l. QOL and TS were assessed using: type 2 Diabetes Symptom Checklist revised (DSC-r), World Health Organization-5 well-being index (WHO-5), Hypoglycaemia Fear Survey (HFS) and Diabetes Treatment Satisfaction Questionnaire (DTSQ). Higher scores indicate greater symptom distress, well-being, worries about hypoglycaemia and TS, respectively. Data were analysed using ANCOVA. RESULTS: HbA1c reductions and overall hypoglycaemia were comparable between glargine and detemir (mean±SD change in HbA1c: -1.46±1.09 and -1.54±1.11%, respectively [P=0.149]). Total diabetes-related symptom distress (DSC-r) decreased in both treatment groups. There were no significant differences between groups, except for the neuropathic pain subscale (P=0.027 in favour of glargine). Well-being (WHO-5) increased equally in both groups (+6.13±21.47 for glargine and +7.54±19.06 for detemir on scale 0-100, P=0.742). There was no significant difference between treatments for the HFS (P=0.441). TS (DTSQ) improved for both treatment groups, but significantly more for glargine than for detemir: Mean±SD increase in total satisfaction score (scale 0-36): 5.1±8.6 for glargine and 4.1±8.8 for detemir (P<0.001). CONCLUSIONS: Initiating glargine once-daily or detemir twice-daily in patients with type 2 diabetes failing OGLDs resulted in similarly improved glycaemic control, associated with an overall positive effect on diabetes symptom distress and emotional well-being. TS improved with both insulins, however, improvement was significantly greater with glargine than detemir.