Analysing the concept of diagnostic inertia in hypertension: a cross-sectional study.

Abstract

The aim of this study was to quantify diagnostic inertia (DI) when the physician fails to diagnose hypertension and determine its associated factors. This cross-sectional, observational study involved all patients without a diagnosis of hypertension who had their blood pressure (BP) measured at least three times during the second half of 2010 (N=48,605). Patients with altered mean BP figures (≥140/90mmHg) were considered to experience DI. Secondary variables: gender, atrial fibrillation, diabetes mellitus, dyslipidemia, cardiovascular disease, age and the physician having attended a cardiovascular training course (ESCARVAL). Associated factors were assessed by multivariate logistic regression analysis. Diagnostic inertia was present in 6450 patients (13.3%, 95% CI: 13.0-13.6%). Factors significantly associated with DI were: male gender (OR=1.46, 95% CI: 1.37-1.55, p<0.001), atrial fibrillation (OR=0.73, 95% CI: 0.58-0.92, p=0.007), the ESCARVAL cardiovascular course (OR=0.88, 95% CI: 0.81-0.96, p=0.005), diabetes mellitus (OR=0.93, 95% CI: 0.87-0.99, p=0.016), cardiovascular disease (OR=0.77, 95% CI: 0.67-0.88, p<0.001) and older age (years) (18-44→OR=1; 45-59→OR=12.45, 95% CI: 11.11-13.94; 60-74→OR=18.11, 95% CI: 16.30-20.12; ≥75→OR=20.43, 95% CI: 18.34-22.75; p<0.001). The multivariate model had an area under the ROC curve of 0.81 (95% CI: 0.80-0.81, p<0.001). This study will help clinical researchers differentiate between the two forms of DI (interpretation of a positive screening test and interpretation of positive diagnostic criteria). The results found here in patients with hypertension suggest that this problem is prevalent, and that a set of associated factors can explain the outcome well (AUC>0.80).