HPLC–MS–MS Indicates Resistant Hypertension in Non-Adherent Patients

May 19, 2014
By LCGC Editors

A new study in the journal Heart suggests that high performance liquid chromatography tandem mass spectrometry (HPLC–MS–MS) could be performed as a standard screening tool to identify patients who do not take the anti-hypertensive medications as prescribed by their doctor. 1 The authors suggest that up to one in four patients is misdiagnosed as suffering with “resistant hypertension”, when in fact the patient has not been taking their prescribed medications as advised.1

It is estimated that around 10–20% of patients suffering with high blood pressure are resistant to standard anti-hypertensive drugs. Patients suffering with long-standing high blood pressure can be referred to specialist clinics for alternative therapies such as renal cauterization, where the nerve endings of the kidney artery walls are at a lower blood pressure.

It is however debated whether or not resistant hypertension is simply the result of not taking prescribed drugs as advised. The authors state that estimates of non-adherence range between 3­–65%. HPLC–MS–MS could be used as a useful screening tool prior to referral to specialist clinics.

The team spot sampled urine from 208 patients with long-standing high blood pressure who had been referred to a specialist hypertension clinic in Leeds, UK. HPLC–MS–MS was performed on the samples to detect the presence of a range of drugs known to be used in the treatment of hypertension.

Of the 208 patients tested, one in four patients were not taking their prescribed medication. Furthermore one in 10 samples did not contain any anti-hypertension medication. The average number of drugs in samples was also lower than expected.

The results suggest that HPLC–MS–MS could be used as a tool to screen for non-adherence to prescribed drug courses, however, the sample size is small and further investigations will need to be carried out in the future.

1. M. Tomaszewski, C. White, P. Patel, et al., Heart First Published Online: April 2, 2014) doi: 10.1136/heartjnl-2013-305