Early intervention models of diabetes care to address adverse glycaemia in hospital

Abstract

Diabetes affects one quarter of individuals in hospital and contributes to worse clinical and economic outcomes. Acute hyperglycaemia causes immune dysfunction, proinflammatory and prothrombotic changes, and endothelial dysfunction, leading to increased risk of hospital-acquired infections, and cardiovascular and renal complications. Acute hypoglycaemia also causes proinflammatory and prothrombotic changes, endothelial dysfunction, and neuroglycopaenia-related complications. ‘Adverse glycaemia’ describes both extremes of hypoglycaemia and hyperglycaemia (defined as glucose <4 or >15 mmol/L), that are associated with adverse pathophysiology and adverse outcomes in hospital. Adverse glycaemia remains common in hospital patients due to various barriers including clinical inertia. This thesis aimed to develop and investigate a strategy of proactive care and early diabetes intervention to address adverse glycaemia in hospital.

A glucose alert system, comprising a novel clinical escalation tool coupled with alert-capable networked glucose meters, was developed to decrease clinical inertia (Chapter 3). In a 14-week, pre- and post- implementation study, the glucose alert system increased nursing and medical staff actions in response to adverse glycaemia, and this translated to a reduction in the incidence of hyperglycaemia.

Networked glucose meter technology was then implemented on eight noncritical medical and surgical care wards at the Royal Melbourne Hospital, enabling detailed baseline assessment of inpatient glycaemia (Chapter 4). In this first detailed glucometric analysis of an Australian hospital, our cohort was found to have a higher incidence of hyperglycaemia but a lower incidence of hypoglycaemia compared to benchmarks in the United States hospitals. A novel glucometric measure of ‘adverse glycaemic days’, defined as patient-days with glucose <4 or >15 mmol/L, was proposed as a useful metric for benchmarking, and as a tangible concept for educating health professionals about safe glycaemic control in hospital.

A comprehensive early intervention model of diabetes care was developed and investigated in the Randomised study of a Proactive Inpatient Diabetes Service (RAPIDS) (Chapter 5). The early intervention model included remote glycaemic surveillance and proactive management of all diabetes patients, by an inpatient diabetes team within 24 hours of admission. RAPIDS, a 24-week cluster randomised trial with a baseline period, involving 1002 consecutive patients, is amongst the largest randomised trials of inpatient diabetes care to date. Early intervention decreased the incidence of adverse glycaemic days by 28%, and decreased severe hyperglycaemia (patient-days with mean glucose >15 mmol/L) by 55%. This intervention was associated with an 80% relative risk reduction (and 4% absolute risk reduction) of developing hospital-acquired infection.

Lastly, a prediction tool to enable early identification of diabetes inpatients at high risk for persistent adverse glycaemia was developed (Chapter 6). A prediction tool based on four clinical factors available at admission (glucose at admission, glucose-lowering treatment regimen, glycosylated haemoglobin and glucocorticoid medication), accurately identified high-risk patients, and may assist delivery of targeted management.

The studies describe models of clinical care which may be implemented as stand-alone or as a bundle of interventions. The findings support the strategy of proactive care to improve inpatient glucose. Proactive and early intervention models of care which improve glycaemia may improve the care of individuals with diabetes in hospital.