Prevalence and risk factors of undiagnosed diabetes mellitus among gastroenterological patients: a HbA(1c)-based single center experience

Background Diabetes mellitus is a major risk factor for microvascular disease, leading to chronic kidney injury or cardiovascular disease, but there is a tremendous proportion of patients worldwide who suffer from undiagnosed diabetes. Until now, little is known about the prevalence of undiagnosed diabetes in gastroenterology inpatients. Objective To improve detection of undiagnosed diabetes, a routine screening procedure for gastroenterology inpatients, based on hemoglobin A(1c) (HbA(1c)) and fasting plasma glucose (FPG) measurement, was established. Methods We conducted a retrospective analysis of the implemented diabetes screening. Diabetes mellitus was diagnosed according to the guideline of the German Diabetes Association in patients with an HbA(1c) of >= 6.5 % anld/or fasting plasma glucose (FPG) >= 126 mg/dL. Univariate and multivariate analyses were performed to identify independent risk factors for undiagnosed diabetes. Results Within a 3-month period, 606 patients were eligible for a diabetes screening. Pre-existing diabetes was documented in 120 patients (19.8 %), undiagnosed diabetes was found in 24 (3.9 %), and 162 patients (26.7%) met the definition for prediabetes. Steroid medication use, age, and liver cirrhosis due to primary sclerosing cholangitis (PSC) were identified as risk factors for undiagnosed diabetes. Conclusion The prevalence of undiagnosed diabetes in gastroenterology inpatients is markedly elevated in comparison to the general population, and a substantial number of inpatients are in a prediabetic status, underlining the need for diabetes screening. In addition to previously described risk factors of patient age and steroid medication use, we identified PSC-related liver cirrhosis (but not liver cirrhosis due to another etiology) as an independent risk factor for undiagnosed diabetes.