Robert Gerald Jan Moes,1 Eline L Huisman,1 Samuel JP Malkin,2 Barnaby Hunt2 1Novo Nordisk BV, Alphen aan den Rijn, Netherlands; 2Ossian Health Economics and Communications, Basel, SwitzerlandCorrespondence: Barnaby Hunt, Ossian Health Economics and Communications GmbH, Bäumleingasse 20, Basel, 4051, Switzerland, Tel +41 61 271 6214, Email hunt@ossianconsulting.comIntroduction: Achieving and maintaining glycemic control is the cornerstone of type 1 diabetes management, with the aim of reducing the incidence of diabetes-related complications over the long term. However, many individuals fail to reach glycemic targets. The present study evaluated the clinical and economic burden associated with poor glycemic control in people with type 1 diabetes in the Netherlands, and the improvements in outcomes that can be achieved by improving treatment.Methods: Immediate glycemic control, defined as achieving a glycated hemoglobin (HbA1c) target of 7.0% at the start of the analysis, was compared with delays in achieving control of 1, 3 and 7 years, with outcomes projected using the IQVIA CORE Diabetes Model. Projections of life expectancy, quality-adjusted life expectancy, and direct and indirect costs (expressed in 2021 euros [EUR]) were made at a patient level and extrapolated to the population level.Results: Improving HbA1c from 8.0% to 7.0% and 9.0% to 7.0% resulted in gains of up to 0.66 and 1.37 quality-adjusted life years (QALYs) per patient over a lifetime, respectively. At a population level, achieving immediate glycemic control was associated with gains of 9438, 27,171 and 72,717 QALYs and cost savings of up to EUR 224 million, EUR 556 million and EUR 1.3 billion compared with remaining in poor control for 1, 3 and 7 years, respectively.Conclusion: The clinical and economic burden of poor glycemic control in people with type 1 diabetes in the Netherlands was projected to be substantial, but considerable gains in quality-adjusted life expectancy and cost savings could be achieved through early and effective ...