Optimisation of quality indicators for lipid-lowering treatment of type 2 diabetes mellitus

INTRODUCTION: The Danish Adult Diabetes Database (DADD) annually reports a quality indicator for lipid-lowering treatment of type 2 diabetes mellitus (T2DM) patients. This retrospective cohort study aims to A) investigate the reasons for inadequate or lacking lipid-lowering treatment and to B) assess the validity of the DADD indicator as a measure of quality of care. METHODS: A) A pop-up questionnaire enquiring about reasons for lack of treatment was added to the clinicians' data entry tool in the Central Denmark Region. B) The DADD indicator was compared on a per-clinic basis with the achieved median low-density lipoprotein (LDL) cholesterol level and with an internationally widely used indicator of lipid-lowering treatment quality. RESULTS: A) A total of 3,491 patients were registered from 1 January 2013 to 28 February 2015. For 170 (62%) of 309 patients with an LDL level ) 2.5 mmol/l who were not receiving lipid-lowering treatment, there was no 'good" explanation for lacking treatment. Among 518 patients with an LDL level > 2.5 mmol/l despite lipid-lowering treatment, 25g (50%) did not receive high-intensity treatment. B) The DADD quality indicator was neither associated with the international quality indicator nor with the median per-clinic LDL level for T2DM patients. CONCLUSIONS: A) We found substantial potential for improvement of lipid management among T2DM patients in Denmark by initiating and/or intensifying lipid-lowering treatment. B) The current DADD indicator is not a valid measure of lipid-lowering quality of care.