Validity of Prescription-Defined and Hospital-Diagnosed Hypertension Compared with Self-Reported Hypertension in Denmark

Kasper Bonnesen,1,2 Morten Schmidt1– 3 1Department of Clinical Epidemiology, Aarhus University and Aarhus University Hospital, Aarhus, Denmark; 2Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; 3Department of Cardiology, Aarhus University Hospital, Aarhus, DenmarkCorrespondence: Kasper Bonnesen, Aarhus University, Olof Palmes Allé 43– 45, 8200 Aarhus N, Denmark, Tel +45 87 16 72 12, Email bonnesen@clin.au.dkPurpose: Hypertension is an important risk factor in cardio-epidemiological research, but data quality remains a concern. We validated different registry-based definitions of hypertension.Patients and Methods: The cohort included all first-time responders of the Danish National Health Surveys (2010, 2013, or 2017). Prescription-defined hypertension was defined as ≥ 1 or ≥ 2 filled prescriptions of antihypertensive specific drugs in ≥ 1 or ≥ 2 different antihypertensive drug classes within 90, 180, or 365 days before survey response. Hospital-diagnosed hypertension was defined from hypertension diagnoses within five years before the survey response. Considering self-reported hypertension as the reference, we calculated the positive predictive value (PPV), the negative predictive value (NVP), the sensitivity, and the specificity of prescription-defined and hospital-diagnosed hypertension.Results: Among 442,490 survey responders, 127,247 (29%) had self-reported hypertension. For prescription-defined hypertension with 365-day lookback, the PPV was highest for ≥ 2 prescriptions in ≥ 2 drug classes (94%) and lowest for ≥ 1 prescription in ≥ 1 drug class (85%). The NPV was highest for ≥ 1 prescription in ≥ 2 drug classes (94%) and lowest for ≥ 1 prescription in ≥ 2 drug classes (80%). The sensitivity was highest for ≥ 1 prescription in ≥ 1 drug class (79%) and lowest for ≥ 2 prescriptions in ≥ 2 drug classes (30%). The specificity was ≥ 94% for all algorithms. The PPV and specificity did not change noteworthy with length of lookback period, whereas the NPV ...