Non-adherence to cardiometabolic medication as assessed by LC-MS/MS in urine and its association with kidney and cardiovascular outcomes in type 2 diabetes mellitus

AIMS/HYPOTHESIS

Non-adherence to medication is a frequent barrier in the treatment of patients with type 2 diabetes mellitus, potentially limiting the effectiveness of evidence-based treatments. Previous studies have mostly relied on indirect adherence measures to analyse outcomes based on adherence. The aim of this study was to use LC-MS/MS in urine-a non-invasive, direct and objective measure-to assess non-adherence to cardiometabolic drugs and analyse its association with kidney and cardiovascular outcomes.

METHODS

This cohort study includes 1125 participants from the PROVALID study, which follows patients with type 2 diabetes mellitus at the primary care level. Baseline urine samples were tested for 79 cardiometabolic drugs and metabolites thereof via LC-MS/MS. An individual was classified as totally adherent if markers for all drugs were detected, partially non-adherent when at least one marker for one drug was detected, and totally non-adherent if no markers for any drugs were detected. Non-adherence was then analysed in the context of cardiovascular (composite of myocardial infarction, stroke and cardiovascular death) and kidney (composite of sustained 40% decline in eGFR, sustained progression of albuminuria, kidney replacement therapy and death from kidney failure) outcomes.

RESULTS

Of the participants, 56.3% were totally adherent, 42.0% were partially non-adherent, and 1.7% were totally non-adherent to screened cardiometabolic drugs. Adherence was highest to antiplatelet and glucose-lowering agents and lowest to lipid-lowering agents. Over a median (IQR) follow-up time of 5.10 (4.12-6.12) years, worse cardiovascular outcomes were observed with non-adherence to antiplatelet drugs (HR 10.13 [95% CI 3.06, 33.56]) and worse kidney outcomes were observed with non-adherence to antihypertensive drugs (HR 1.98 [95% CI 1.37, 2.86]).

CONCLUSIONS/INTERPRETATION

This analysis shows that non-adherence to cardiometabolic drug regimens is common in type 2 diabetes mellitus and negatively affects kidney and cardiovascular outcomes.

Measuring adherence to antihypertensive medication using an objective test in older adults attending primary care: cross-sectional study

Analysis of urine samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS) has previously revealed high rates of non-adherence to antihypertensive medication. It is unclear whether these rates represent those in the general population. This study aimed to investigate whether it is feasible to collect urine samples in a primary care setting and analyse them using LC-MS/MS to detect non-adherence to antihypertensive medication. This study used a prospective, observational cohort design. Consecutive patients were recruited opportunistically from five general practices in UK primary care. They were aged ≥65 years with hypertension and had at least one antihypertensive prescription. Participants were asked to provide a urine sample for analysis of medication adherence. Samples were sent to a laboratory via post and analysed using LC-MS/MS. Predictors of adherence to medication were explored with multivariable logistic regression. Of 349 consecutive patients approached for the study, 214 (61.3%) gave informed consent and 191 (54.7%) provided a valid urine sample for analysis. Participants were aged 76.2 ± 6.6 years and taking a median of 2 antihypertensive medications (IQR 1-3). A total of 27/191 participants (14.2%) reported not taking all of their medications on the day of urine sample collection. However, LC-MS/MS analysis of samples revealed only 4/27 (9/191 in total; 4.7%) were non-adherent to some of their medications. Patients prescribed more antihypertensive medications were less likely to be adherent (OR 0.24, 95%CI 0.09-0.65). Biochemical testing for antihypertensive medication adherence is feasible in routine primary care, although non-adherence to medication is generally low, and therefore widespread testing is not indicated.

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.

Nonadherence in Hypertension: How to Develop and Implement Chemical Adherence Testing

Nonadherence to antihypertensive medication is common, especially in those with apparent treatment-resistant hypertension (true treatment-resistant hypertension requires exclusion of nonadherence), and its routine detection is supported by clinical guidelines. Chemical adherence testing is a reliable and valid method to detect adherence, yet methods are unstandardized and are not ubiquitous. This article describes the principles of chemical adherence testing for hypertensive patients and provides a set of recommendations for centers wishing to develop the test. We recommend testing should be done in either of two instances: (1) in those who have resistant hypertension or (2) in those on 2 antihypertensives who have a less than 10 mm Hg drop in systolic blood pressure on addition of the second antihypertensive medication. Furthermore, we recommend that verbal consent is secured before undertaking the test, and the results should be discussed with the patient. Based on medications prescribed in United Kingdom, European Union, and United States, we list top 20 to 24 drugs that cover >95% of hypertension prescriptions which may be included in the testing panel. Information required to identify these medications on mass spectrometry platforms is likewise provided. We discuss issues related to ethics, sample collection, transport, stability, urine versus blood samples, qualitative versus quantitative testing, pharmacokinetics, instrumentation, validation, quality assurance, and gaps in knowledge. We consider how to best present, interpret, and discuss chemical adherence test results with the patient. In summary, this guidance should help clinicians and their laboratories in the development of chemical adherence testing of prescribed antihypertensive drugs.

Non-adherence to heart failure medications predicts clinical outcomes: assessment in a single spot urine sample by liquid chromatography-tandem mass spectrometry (results of a prospective multicentre study)

AIMS

Liquid chromatography-mass spectrometry (LC-MS/MS) is an objective new technique to assess non-adherence to medications. We used this method to study the prevalence, predictors and outcomes of non-adherence in patients with heart failure with reduced left ventricular ejection fraction (HFrEF).

METHODS AND RESULTS

This study included 1296 patients with HFrEF from BIOSTAT-CHF, a study that aimed to optimise guideline-recommended therapies. Angiotensin-converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARBs), mineralocorticoid receptor antagonists, β-blockers and loop diuretics were measured in a single spot urine sample at 9 months using LC-MS/MS. The relationship between medication non-adherence and the composite endpoint of all-cause death or heart failure hospitalisation, over a median follow-up of 21 months, was evaluated. Non-adherence to at least one prescribed medication was observed in 45.9% of patients. The strongest predictor of non-adherence was non-adherence to any of the other medication classes (P < 0.0005). Regional differences within Europe were observed. On multivariable analyses, non-adherence to ACEi/ARBs and β-blockers was associated with an increased risk of the composite endpoint [hazard ratio (HR) 1.38, 95% confidence interval (CI) 1.09-1.95, P = 0.008 and HR 1.48, 95% CI 1.12-1.96, P = 0.006, respectively). Non-adherence to β-blockers was also associated with an increased risk of death (HR 2.48, 95% CI 1.67-3.68, P < 0.0005). Patients who were non-adherent to loop diuretics were healthier and had a decreased risk of the composite endpoint (HR 0.69, 95% CI 0.51-0.93, P = 0.014). Non-adherence to mineralocorticoid receptor antagonists was not related to any clinical outcome.

CONCLUSION

Non-adherence to medications, assessed by a single urine test, is common and predicts clinical outcomes in patients with HFrEF.

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.

Hyphenated mass spectrometry techniques for assessing medication adherence: advantages, challenges, clinical applications and future perspectives

Nonadherence to prescribed pharmacotherapy is an understated public health problem globally and is costing many patients their chance to return to good health and healthcare systems billions. Clinicians need an accurate assessment of adherence to medications to aid the clinical decision-making process in the event of poor patient progress and to maximise the patient health outcomes from the drug therapies prescribed. An overview of indirect and direct methods used to measure medication adherence is presented, highlighting the potential for accurate measuring of drugs in biological samples using hyphenated mass spectrometry (MS) techniques to provide healthcare professionals with a reliable evidence base for clinical decision making. In this review we summarise published applications of hyphenated MS techniques for a diverse range of clinical areas demonstrating the rise in the use of such direct methods for assessing medication adherence. Although liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods using plasma, serum and urine samples are the most popular, in recent years increased attention has been given to liquid chromatography high-resolution mass spectrometry (LC-HRMS) methods and alternative biosample matrices including hair, saliva and blood microsamples. The advantages and challenges of using hyphenated MS techniques to address this healthcare problem are also discussed alongside future perspectives.

Scales for assessing medication adherence in patients with hypertension

BACKGROUND

the choice of the appropriate tool for assessing level of medication adherence is a significant barrier in scientific research.

AIMS

to translate into Greek and test the reliability of the Hill-Bone and A-14 scales among patients with hypertension. Also, to compare patients' responses in the Hill-Bone scale, A-14 scale and Morisky Medication Adherence Scale (MMAS).

METHODS

data collection occurred between February 2016 and March 2016 at a general hospital in Athens, Greece. The sample consisted of hypertensive patients (n=34) and non-hypertensive patients (n=34).

FINDINGS

the coefficient alpha in hypertensive patients was 0.76 for Hill-Bone, 0.64 for MMAS and 0.91 for the A-14 scale. In non-hypertensive patients, the Cronbach's alpha for MMAS was 0.81 and 0.78 for A-14. A statistically significant difference was found among the mean scores of the scales, whereas strong correlation was found only between two pairs of questions with similar meaning.

CONCLUSION

all tools are appropriate to assess the level of medication adherence in Greek hypertensive patients. However, careful translation of the scales is essential since items with the same meaning could be understudied in a different way.

Objective measures of non-adherence in cardiometabolic diseases: a review focused on urine biochemical screening

Cardiometabolic diseases are among the most prevalent and harmful conditions worldwide. They are complex, comorbid conditions that require polypharmacy - a known contributor to non-adherence in cardiovascular disease (CVD) and diabetes mellitus (DM). Suboptimal adherence is associated with poor disease control, which increases the risk of hospitalizations, mortality, and preventable financial implications. However, until recently, the lack of a gold standard for non-adherence testing in cardiometabolic diseases has been the major barrier for understanding true prevalence and mortality consequences. Recent European guidelines have endorsed biochemical testing as the preferred measure for non-adherence in CVD, with urinary screening methods being the most clinically widespread. The diagnostic and therapeutic benefits incurred to health service resources by use of biochemical non-adherence testing are vast, as hospitalizations and associated economic burdens are reduced, and tailored therapies are increased. However, biochemical testing can only signify a snap shot of adherence behavior, and true adherence may be skewed by pharmacokinetic factors. This review summarizes current literature regarding the prevalence, impact, and reasons of non-adherence in cardiometabolic disease. The benefits of current adherence diagnostic tools have been appraised, where urine in biochemical testing has been focused upon and evaluated against other matrices.