Urine Concentration Does Not Affect Biochemical Testing for Non-adherence

Hypertension is one of the most important modifiable risk factor causing cardiovascular disease. Unfortunately, non-adherence to antihypertensive medications is frequently observed in hypertensive patients and can lead to an increase in morbidity and mortality. Until recently, there was no robust clinical method to objectively diagnose non-adherence. Recently, the detection of medications in urine or blood by mass spectrometry techniques such as liquid chromatography-tandem mass spectrometry (LC–MS-MS) has been accepted as the diagnostic method of choice for the detection of non-adherence. Despite this, it is unclear whether the concentration of urine can affect the detection of medications in urine. Therefore, this study aimed to assess the effect of urine concentration on detection of antihypertensive medications by LC–MS-MS in which urine creatinine is used as an independent marker of urine concentration. Biochemical adherence results for 22 different medications (1,709 prescriptions) in 463 different subjects were converted to an adherence score. The adherence score was defined as the ratio of the total number of subjects in which the drug was detected to the total number of subjects to whom the drug was prescribed. The adherence scores for each medication were correlated with urine creatinine concentration for each medication. Non-adherence was observed in 47.1% of samples with a mean urine creatinine concentration of these samples of 9.4 ± 7.1 mmol/L. There was no significant difference between the urine creatinine concentrations in the detected vs non-detected groups for each of the 22 medications. Furthermore, there are no differences in adherence scores across the urine creatinine concentration. This is the first study to demonstrate that urine creatinine concentration does not affect the results of the adherence screening by LC–MS-MS.</p

An Innovative Chemical Adherence Test Demonstrates Very High Rates of Nonadherence to Oral Cardio-Metabolic Medications

Chronic kidney disease (CKD) is one of the leading causes of death worldwide. About 13% of the world’s population are living with CKD; and over the last 20 years, there has been over a 40% increase in mortality rates due to CKD.1,2 Compared to patients without CKD, CKD stages G3a to G4 (estimated glomerular filtration rate 15–60 ml/min per 1.73 m2) is associated with a 2 to 3 fold increase in risk of cardiovascular disease mortality.3 It is estimated that about 17% to 74% of patients with CKD are nonadherent to their medications.4 Improvement in adherence has been identified as a key strategy to enhance cardiovascular outcomes.5 However, the diagnosis of nonadherence, until recently, was difficult due to the lack of objective tools in busy clinics because some subjective methods have been found to be unreliable.6 Chemical adherence testing (CAT) is a novel, objective, robust and clinically reliable test that uses liquid-chromatography tandem mass spectrometry to assess adherence to medications. A random spot urine or blood sample is screened to determine the presence or absence of 70 of the most common cardio-metabolic medications (Supplementary Table S1) (including antihypertensives, lipid lowering medications, and glucose lowering drugs).7 There are guidelines available to help implement the use of the test and address common questions about the clinical use of the test.7 Currently, CAT is being used in routine care in some specialist hypertension clinics across Europe and has been recommended by the European Society of Cardiology and the European Society of Hypertension as the method to be used to measure adherence in patients with suspected resistant hypertension.8 The use of CAT is limited outside of hypertension and to the best of our knowledge there has been no publication that has used CAT to diagnose medication nonadherence in renal patients. The aim of this study was therefore to demonstrate and highlight the usefulness of CAT to determine the prevalence of nonadherence to cardio-metabolic medications in patients attending routine renal clinics.</p

High non-adherence rates to secondary prevention by chemical adherence testing in patients with TIA

Introduction: Transient ischaemic attack (TIA) clinics are important for secondary prevention of fatal or disabling stroke. Non-adherence to prescribed medications is an important reason for treatment failure but difficult to diagnose. This study ascertained the utility of a novel biochemical tool in the objective biochemical diagnosis of non-adherence. Methods: One-hundred consecutive urine samples collected from patients attending the TIA clinic, at a tertiary centre, were analysed for presence or absence of prescribed cardiovascular medications using liquid chromatography-mass spectrometry (LC-MS/MS). Patients were classified as adherent or non-adherent, respectively. Demographic and clinical characteristics were compared between the two cohorts. Univariate regression analyses were performed for individual variables and model fitting was undertaken for significant variables. Results: The mean duration of follow-up from the index event was 31 days [standard deviation (SD): 18.9]. The overall rate of non-adherence for at least one medication was 24%. In univariate analysis, the number of comorbidities [3.4 (SD: 1.9) vs. 2.5 (1.9), P = 0.032] and total number of all prescribed medications [6.0 (3.3) vs 4.4 (2.1), P = 0.032] were higher in the non-adherent group. On multivariate analysis, the total number of medications prescribed correlated with increased non-adherence (odds ratio: 1.27, 95% Confidence Intervals: 1.1-1.5, P = 0.01). Conclusions: LC-MS/MS is a clinically useful tool for the diagnosis of non-adherence. Nearly a quarter of TIA patients were non-adherent to their cardiovascular medications Addressing non-adherence early may reduce the risk of future disabling cardiovascular events

V392 Persei: A γ-ray bright nova eruption from a known dwarf nova

V392 Persei is a known dwarf nova (DN) that underwent a classical nova eruption in 2018. Here we report ground-based optical, Swift UV and X-ray, and Fermi-LAT γ-ray observations following the eruption for almost three years. V392 Per is one of the fastest evolving novae yet observed, with a t2 decline time of 2 d. Early spectra present evidence for multiple and interacting mass ejections, with the associated shocks driving both the γ-ray and early optical luminosity. V392 Per entered Sun-constraint within days of eruption. Upon exit, the nova had evolved to the nebular phase, and we saw the tail of the supersoft X-ray phase. Subsequent optical emission captured the fading ejecta alongside a persistent narrow line emission spectrum from the accretion disc. Ongoing hard X-ray emission is characteristic of a standing accretion shock in an intermediate polar. Analysis of the optical data reveals an orbital period of 3.230 ± 0.003 d, but we see no evidence for a white dwarf (WD) spin period. The optical and X-ray data suggest a high mass WD, the pre-nova spectral energy distribution (SED) indicates an evolved donor, and the post-nova SED points to a high mass accretion rate. Following eruption, the system has remained in a nova-like high mass transfer state, rather than returning to the pre-nova DN low mass transfer configuration. We suggest that this high state is driven by irradiation of the donor by the nova eruption. In many ways, V392 Per shows similarity to the well-studied nova and DN GK Persei