Treating depression in diabetes patients: does a nurse-administered minimal psychological intervention affect diabetes-specific quality of life and glycaemic control? A randomized controlled trial

AIMS: The aim of this study was to examine whether a nurse-administered minimal psychological intervention for depressive symptoms improves diabetes-specific quality of life and glycaemic control in older persons with diabetes. BACKGROUND: Depression is common among persons with diabetes and may have a negative impact on diabetes. Interventions aimed at reducing depressive symptoms may positively influence diabetes-specific quality of life as well. METHODS: A pragmatic, randomized controlled trial was carried out comparing the intervention with usual care among 208 Dutch primary care patients of ≥60 years with type 2 diabetes and co-occurring minor to moderate depression. Data on symptom distress and emotional distress were collected during 2003-2006, and haemoglobin A1c levels were obtained from general practices. Data were analysed using mixed model, repeated measures ANCOVAS. Hba1c was collected retrospectively from general practices between December 2006-February 2007. In July 2007 we retrieved some additional HbA1c data from the medical records of the university hospital. RESULTS: Only in higher-educated persons did the intervention have statistically significant effect on both emotional distress and symptom distress (DSC-R total score at 9 months P=0.001; PAID, 9 months P=0.03). Furthermore, we found an effect on symptom distress in men (9 months P=0.01), and on emotional distress in persons with a shorter diabetes duration (<7 years) (9 months P=0.04). A significant trend over time for haemoglobin A1c was found in favour of the intervention, with a statistically significant difference between groups after 9 months (P=0.02). CONCLUSION: The nurse-administered intervention had limited effects on diabetes-specific quality of life. As only certain subgroups benefited, ways of increasing effectiveness in other groups should be explored. The potentially beneficial effect on glycaemic control is encouraging and needs further research because of small numbers in the analysis.