Psychometric and screening properties of the WHO-5 well-being index in adult outpatients with Type 1 or Type 2 diabetes mellitus.

OBJECTIVE: The 5-item World Health Organization well-being index is a commonly used measure of emotional well-being, but research on psychometric properties in outpatients with diabetes is scarce. We examined psychometric and screening properties for depression of this index in a large sample of Dutch outpatients with diabetes. METHODS: Patients with Type 1 (n = 384) and Type 2 (n = 549) diabetes from three outpatient clinics completed the WHO-5 index, the nine-item Patient Health Questionnaire, the Problem Areas in Diabetes survey and the Short Form-12 health survey. Internal consistency of the WHO-5 index was determined by Cronbach's alpha. The factor structure was tested by confirmatory factor analysis. Concurrent validity was assessed by correlations with the Patient Health Questionnaire, Problem Areas in Diabetes and the Short Form-12 mental component scores. Sensitivity and specificity of the WHO-5 index as depression screener were tested against two existing Patient Health Questionnaire cut-off scores for depression using receiver operating characteristic curves. RESULTS: A one-factor structure of the WHO-5 index was verified by confirmatory factor analysis for patients with Type 1 and Type 2 diabetes. Moderate to strong correlations were observed between the WHO-5 index and the Patient Health Questionnaire scores, the Problem Areas in Diabetes scores and the Short Form-12 mental component scores (r = 0.55-0.69, P < 0.001). Receiver operating characteristic curves showed that a WHO-5 index cut-off of < 50 performed best as an indication for likely depression, with sensitivity compared with a Patient Health Questionnaire score ≥ 10 and ≥ 12 of 79% and 88%, respectively, and specificity of 88% and 76%, respectively. CONCLUSIONS: The WHO-5 index is a short, psychometrically sound measure of emotional well-being that appears suitable for use as screening test for likely depression in outpatients with Type 1 and Type 2 diabetes.

The longitudinal association between glycaemic control and health-related quality of life following insulin therapy optimisation in type 2 diabetes patients. A prospective observational study in secondary care.

PURPOSE: To test whether improvement in glycosylated haemoglobin (HbA(1c)) as a marker of glycaemic control, following intensifying insulin therapy, is associated with improvements in HRQoL. METHODS: Dutch sub-optimally controlled (HbA(1c) > 7%) type 2 diabetes patients (N = 447, mean age 59 ± 11) initiated insulin glargine therapy. Data were collected at baseline, 3 and 6 months, and included HbA(1c) and measures of HRQoL: diabetes symptom distress (Diabetes Symptom Checklist-revised; DSC-r), fear of hypoglycaemia (Hypoglycaemia Fear Survey; HFS-w) and emotional well-being (WHO-5 wellbeing index). RESULTS: HbA(1c) decreased from 8.8 ± 1.4% to 8.0 ± 1.2% and 7.7 ± 1.3% at 3 and 6 months follow-up, respectively (P < 0.001), DSC-r score improved from 17.7 ± 14.7 to 14.3 ± 13.3 and 13.6 ± 13.3 (P < 0.001). HFS-w score did not significantly change. WHO-5 score increased from 56 ± 23 to 62 ± 23 and 65 ± 22 P < 0.001). A modest, significant association was found between HbA(1c) and WHO-5 score (B = -1.8, 95% CI: -2.7 to -0.8) and HbA1c and DSC-r score (B = 1.0, 95% CI: 0.4 to 1.6). No such association was found for HFS-w score. CONCLUSIONS: An association between improvement in HbA(1c) by means of optimising insulin therapy and improvement in HRQoL in type 2 diabetes patients has been observed. A weak, yet significant longitudinal association was found between improved HbA(1c) and emotional well-being and diabetes symptom distress.

Initiation of insulin glargine in patients with Type 2 diabetes in suboptimal glycaemic control positively impacts health-related quality of life. A prospective cohort study in primary care.

AIMS: To study prospectively the impact of initiating insulin glargine in suboptimally controlled insulin-naïve patients with Type 2 diabetes on health-related quality of life in relation to glycaemic control. METHODS: Insulin-naïve Dutch patients with Type 2 diabetes in suboptimal glycaemic control (HbA(1c) > 53 mmol/mol; 7%) on maximum dose of oral glucose-lowering medications were included from 363 primary care practices (n = 911). Patients started insulin glargine and were followed up for 6 months. At baseline (start insulin therapy), 3 and 6 months, HbA(1c) was measured and patients completed self-report health-related quality of life measures, including emotional well-being (World Health Organization-5 well-being index), fear of hypoglycaemia (Hypoglycaemia Fear Survey) and diabetes symptom distress (Diabetes Symptom Checklist-revised). Data were analysed using generalized estimating equations analysis. RESULTS: HbA(1c) (mmol/mol; %) decreased from 69 ± 16; 8.5 ± 1.7 to 60 ± 11; 7.6 ± 1.0 and 57 ± 11; 7.3 ± 1.0 at 3 and 6 months, respectively (P < 0.001). Pre-insulin BMI (kg/m(2) ) was 30 ± 5.7, which remained stable at 3 months (30 ± 5.8) and increased to 31 ± 5.9 at 6 months (P = 0.004); no significant changes in self-reported symptomatic and severe hypoglycaemia were observed, while nocturnal hypoglycaemia slightly decreased. The Hypoglycaemia Fear Survey score decreased from 14.6 ± 16.2 to 12.1 ± 15.2 and 10.8 ± 14.4 at 3 and 6 months, respectively (P < 0.001). The Diabetes Symptom Checklist-revised score decreased from 15 ± 14 to 10 ± 12 and 10 ± 13 (P < 0.001), with most pronounced reductions in hyperglycaemic symptoms and fatigue. The World Health Organization-5 score increased from 57 ± 25.3 to 65 ± 21.6 at 3-month follow-up and 67 ± 21.8 at 6-month follow-up (P < 0.001). CONCLUSIONS: Results of this observational study demonstrate combined glycaemic and health-related quality of life benefits of initiating insulin glargine in patients with Type 2 diabetes in routine primary care.