Defining Hypertension, Diabetes, and Anemia in Research

In HNR, all laboratory data had been analyzed centrally in the laboratory of the university hospital of Essen. Serum creatinine (according to Jaffé) was determined on a Siemens Healthcare Diagnostics ADVIA Chemistry. Serum creatinine was not standardized to isotope dilution mass spectrometry. Hypertension was defined as either a blood pressure of at least 140 mmHg systolic or at least 90 mmHg diastolic or taking antihypertensive medication. Blood pressure cut-offs were selected according to the cut-offs used to define hypertension in the validated risk models. Diabetes was defined according to the respective definitions used in the risk models: either self-reported prevalent diabetes [27 (link), 28 (link)] or using a combination of known diabetes or taking antidiabetic drugs [29 (link), 30 (link)]. Albuminuria was defined as albumin/creatinine ratio (ACR) ≥ 30 mg/dl. In all models except the Kwon model, anemia was coded if hemoglobin levels were < 12 g/dl. In the Kwon model, the threshold for hemoglobin was < 12 g/dl for women and < 13 g/dl for men. Peripheral vascular artery disease was defined according to clinical information.