Background: Resistant Hypertension is defined as uncontrolled high BP despite treatment with at least three antihypertensive agents. The underlying cause is usually found to be phaeochromocytoma, Conns or renal artery stenosis (RAS). We would like to present two cases with difficult control of hypertension which did not fall into these categories.
Case 1: History: 68 year old gentleman presented 2012 with >10 year history of hypertension. BP 200/100. Medical history: strokes, obstructive sleep apnoea, LVH, T2 DM, cervical spondylosis, psoriasis, partial sightedness. Drug treatment: 15 different medications, including 4 antihypertensives.
Investigations: USS kidneys ruled out RAS, normal urine metanephrines and plasma renin measurements excluded phaeochromocytoma and Conns respectively. 24 hr BP excluded white coat syndrome. Renal denervation offered but declined. After 3 years of monitoring and medication adjustment, with no improvement in BP, a urine screen showed that no antihypertensive medications were present.
Outcome: Patient admitted hiding tablets as he could not cope with amount of medication. Hypertension medications reviewed and reduced to 2 which he now takes. July 2015 BP 130/78.
Case 2: History: 47 year old gentleman admitted 2013 with resistant hypertension. BP 168/90. Medical history: glomerulonephritis, IHD with recurrent angina, CVA with post stroke seizures, intracranial bleed. Drug treatment: 16 different medications, including 7 antihypertensives.
Investigations: Cushings, phaeochromocytoma excluded with normal UFCs and urine metanephrines respectively. MRI kidneys showed no significant narrowing. Unmeasurable aldosterone excluded Conns. 24 hr BP excluded white coat syndrome. After 3 years with no improvement, urine screen sent for analysis which showed the only drug detected was hydralazine.
Outcome: Patient confirmed he was hiding tablets as he didnt want any major side effects. Medication reviewed. All antihypertensives stopped except amlodipine 10 mg. BP 120/85.
Conclusion: The issue of adherence should be considered if all other causes of resistant hypertension have been excluded. Urine screen sent for analysis using mass spectrometry is not a quantitative assay, but will confirm compliance. This needs to be handled very tactfully to continue to engage the patient.