To assess to what extent resistant hypertension (RH) differs from uncontrolled hypertension (UH) in hypertensive patients followed-up by general practitioners (GP) or cardiologists.
In a cross-sectional study hypertensives were included if treated with ≥1 antihypertensive drug for ≥1 year. and BP≥140/90 mmHg or ≥130/80 mmHg if diabetes or renal failure. At analysis, each hypertension was classified as RH or UH (non-resistant), and thus as case or control. The RH definition was applied: BP uncontrolled although treated with ≥3 antihypertensive drugs from different classes, including a thiazide diuretic.
1911 and 2179 treated but uncontrolled hypertensive patients were recruited by 500 GPs and 571 cardiologists. RH prevalence was lower in the GP: 15 vs. 29%. GP patients had significantly less CV risk factors, subclinical organ damages and CV or renal diseases. Significant factors associated to RH were: renal diseases (OR = 4.7), antihypertensive treatment for > 7 years (OR = 3.1), subclinical organ damages (OR = 2.2), concomitant CV disease (OR = 2.0), known white-coat effect (OR = 1.9), diabetes (OR = 1.8), serious co-morbidity (OR = 1.7), age >65 years (OR = 1.6), PP >70 mmHg (OR = 1.5), recent antihypertensive intolerance (OR = 1.6), dyslipidaemia (OR = 1.6), abdominal obesity (OR = 1.5), BP control history for > 5 years (OR = 1.3). The majority of patients had lost hypertension control, and patients now resistant, similarly (78%), although a control history had significantly protected against RH (OR = 0.7).
Only up to about 30% of treated but uncontrolled hypertensive patients are treatment-resistant. Resistant hypertension most often results from previously controlled hypertension. BP control seems to delay this failure.