Self-Reported Medication Use and Urinary Drug Metabolites in the German Chronic Kidney Disease (GCKD) Study

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.

Association Between Self-Reported Medication Adherence and Therapeutic Inertia in Hypertension: A Secondary Analysis of SPRINT (Systolic Blood Pressure Intervention Trial)

BACKGROUND

Therapeutic inertia (TI), failure to intensify antihypertensive medication when blood pressure (BP) is above goal, remains prevalent in hypertension management. The degree to which self-reported antihypertensive adherence is associated with TI with intensive BP goals remains unclear.

METHODS AND RESULTS

Cross-sectional analysis was performed of the 12-month visit of participants in the intensive arm of SPRINT (Systolic Blood Pressure Intervention Trial), which randomized adults to intensive (<120 mm Hg) versus standard (<140 mm Hg) systolic BP goals. TI was defined as no increase in antihypertensive regimen intensity score, which incorporates medication number and dose, when systolic BP is ≥120 mm Hg. Self-reported adherence was assessed using the 8-Item Morisky Medication Adherence Scale (MMAS-8) and categorized as low (MMAS-8 score <6), medium (MMAS-8 score 6 to <8), and high (MMAS-8 score 8). Poisson regressions estimated prevalence ratios (PRs) and 95% CIs for TI associated with MMAS-8. Among 1009 intensive arm participants with systolic BP >120 mm Hg at the 12-month visit (mean age, 69.6 years; 35.2% female, 28.8% non-Hispanic Black), TI occurred in 50.8% of participants. Participants with low adherence (versus high) were younger and more likely to be non-Hispanic Black or smokers. The prevalence of TI among patients with low, medium, and high adherence was 45.0%, 53.5%, and 50.4%, respectively. After adjustment, neither low nor medium adherence (versus high) were associated with TI (PR, 1.11 [95% CI, 0.87-1.42]; PR, 1.08 [95% CI, 0.84-1.38], respectively).

CONCLUSIONS

Although clinician uncertainty about adherence is often cited as a reason for why antihypertensive intensification is withheld when above BP goals, we observed no evidence of an association between self-reported adherence and TI.

Expectation of clinical decision support systems: a survey study among nephrologist end-users

BACKGROUND

Chronic kidney disease (CKD), a major public health problem with differing disease etiologies, leads to complications, comorbidities, polypharmacy, and mortality. Monitoring disease progression and personalized treatment efforts are crucial for long-term patient outcomes. Physicians need to integrate different data levels, e.g., clinical parameters, biomarkers, and drug information, with medical knowledge. Clinical decision support systems (CDSS) can tackle these issues and improve patient management. Knowledge about the awareness and implementation of CDSS in Germany within the field of nephrology is scarce.

PURPOSE

Nephrologists' attitude towards any CDSS and potential CDSS features of interest, like adverse event prediction algorithms, is important for a successful implementation. This survey investigates nephrologists' experiences with and expectations towards a useful CDSS for daily medical routine in the outpatient setting.

METHODS

The 38-item questionnaire survey was conducted either by telephone or as a do-it-yourself online interview amongst nephrologists across all of Germany. Answers were collected and analysed using the Electronic Data Capture System REDCap, as well as Stata SE 15.1, and Excel. The survey consisted of four modules: experiences with CDSS (M1), expectations towards a helpful CDSS (M2), evaluation of adverse event prediction algorithms (M3), and ethical aspects of CDSS (M4). Descriptive statistical analyses of all questions were conducted.

RESULTS

The study population comprised 54 physicians, with a response rate of about 80-100% per question. Most participants were aged between 51-60 years (45.1%), 64% were male, and most participants had been working in nephrology out-patient clinics for a median of 10.5 years. Overall, CDSS use was poor (81.2%), often due to lack of knowledge about existing CDSS. Most participants (79%) believed CDSS to be helpful in the management of CKD patients with a high willingness to try out a CDSS. Of all adverse event prediction algorithms, prediction of CKD progression (97.8%) and in-silico simulations of disease progression when changing, e. g., lifestyle or medication (97.7%) were rated most important. The spectrum of answers on ethical aspects of CDSS was diverse.

CONCLUSION

This survey provides insights into experience with and expectations of out-patient nephrologists on CDSS. Despite the current lack of knowledge on CDSS, the willingness to integrate CDSS into daily patient care, and the need for adverse event prediction algorithms was high.

CKD Urine Metabolomics: Modern Concepts and Approaches

One of the primary challenges regarding chronic kidney disease (CKD) diagnosis is the absence of reliable methods to detect early-stage kidney damage. A metabolomic approach is expected to broaden the current diagnostic modalities by enabling timely detection and making the prognosis more accurate. Analysis performed on urine has several advantages, such as the ease of collection using noninvasive methods and its lower protein and lipid content compared with other bodily fluids. This review highlights current trends in applied analytical methods, major discoveries concerning pathways, and investigated populations in the context of urine metabolomic research for CKD over the past five years. Also, we are presenting approaches, instrument upgrades, and sample preparation modifications that have improved the analytical parameters of methods. The onset of CKD leads to alterations in metabolism that are apparent in the molecular composition of urine. Recent works highlight the prevalence of alterations in the metabolic pathways related to the tricarboxylic acid cycle and amino acids. Including diverse patient cohorts, using numerous analytical techniques with modifications and the appropriate annotation and explanation of the discovered biomarkers will help develop effective diagnostic models for different subtypes of renal injury with clinical applications.

Cardiovascular complications in chronic kidney disease: a review from the European Renal and Cardiovascular Medicine Working Group of the European Renal Association

Chronic kidney disease (CKD) is classified into five stages with kidney failure being the most severe stage (stage G5). CKD conveys a high risk for coronary artery disease, heart failure, arrhythmias, and sudden cardiac death. Cardiovascular complications are the most common causes of death in patients with kidney failure (stage G5) who are maintained on regular dialysis treatment. Because of the high death rate attributable to cardiovascular (CV) disease, most patients with progressive CKD die before reaching kidney failure. Classical risk factors implicated in CV disease are involved in the early stages of CKD. In intermediate and late stages, non-traditional risk factors, including iso-osmotic and non-osmotic sodium retention, volume expansion, anaemia, inflammation, malnutrition, sympathetic overactivity, mineral bone disorders, accumulation of a class of endogenous compounds called 'uremic toxins', and a variety of hormonal disorders are the main factors that accelerate the progression of CV disease in these patients. Arterial disease in CKD patients is characterized by an almost unique propensity to calcification and vascular stiffness. Left ventricular hypertrophy, a major risk factor for heart failure, occurs early in CKD and reaches a prevalence of 70-80% in patients with kidney failure. Recent clinical trials have shown the potential benefits of hypoxia-inducible factor prolyl hydroxylase inhibitors, especially as an oral agent in CKD patients. Likewise, the value of proactively administered intravenous iron for safely treating anaemia in dialysis patients has been shown. Sodium/glucose cotransporter-2 inhibitors are now fully emerged as a class of drugs that substantially reduces the risk for CV complications in patients who are already being treated with adequate doses of inhibitors of the renin-angiotensin system. Concerted efforts are being made by major scientific societies to advance basic and clinical research on CV disease in patients with CKD, a research area that remains insufficiently explored.

Estimated Lifetime Benefit of Combined RAAS and SGLT2 Inhibitor Therapy in Patients with Albuminuric CKD without Diabetes

BACKGROUND AND OBJECTIVES

Despite high rates of complications in patients with CKD without diabetes, the implementation of proven therapies in this group remains low. Expressing the clinical benefit of a therapy in terms of extra years free from the disease or death may facilitate implementation. We estimated lifetime survival free of kidney failure for patients with albuminuric CKD without diabetes treated with the combination therapy of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and sodium-glucose cotransporter-2 (SGLT2) inhibitors relative to patients not treated.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We used trial-level estimates of the effect of treatment with angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ramipril/benazepril; n=690) and SGLT2 inhibitors (dapagliflozin; n=1398) compared with placebo to derive the effect of combination therapy versus no treatment. Using this effect, we estimated treatment effect of combination therapy to the active treatment group of patients with albuminuric CKD without diabetes participating in the Dapagliflozin and Prevention of Adverse Outcomes in Chronic Kidney Disease (DAPA-CKD) trial (n=697) and projected eventfree and overall survival for those treated and not treated with combination therapy. We also performed our calculations anticipating lower adherence and less pronounced benefits than were observed in the clinical trials. The primary outcome was a composite of doubling of serum creatinine, kidney failure, or death.

RESULTS

The aggregate estimated hazard ratio comparing combination therapy with angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and SGLT2 inhibitor versus no treatment for the primary end point was 0.35 (95% confidence interval, 0.30 to 0.41). For a 50-year-old patient until the age of 75 years, the estimated survival free from the primary composite end point was 17.0 (95% confidence interval, 12.4 to 19.6) years with the combination therapy and 9.6 years (95% confidence interval, 8.4 to 10.7) with no treatment with any of these agents, corresponding to a gain in eventfree survival of 7.4 (95% confidence interval, 6.4 to 8.7) years. When assuming lower adherence and less pronounced efficacy of combination therapy, the gain in eventfree survival ranged from 5.3 years (95% confidence interval, 4.4 to 6.1) to 5.8 years (95% confidence interval, 4.8 to 6.8).

CONCLUSIONS

Treatment with the combination of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and SGLT2 inhibitor in patients with albuminuric CKD without diabetes is expected to substantially increase kidney failure-free survival.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Benazepril for Advanced Chronic Renal Insufficiency, NCT00270426, and a Study to Evaluate the Effect of Dapagliflozin on Renal Outcomes and Cardiovascular Mortality in Patients with Chronic Kidney Disease (Dapa-CKD), NCT03036150.

Prevalence, phenotypic characteristics and prognostic role of apparent treatment resistant hypertension in the German Chronic Kidney Disease (GCKD) study

Treatment resistant hypertension (TRH) appears of particular relevance in patients with chronic kidney disease (CKD). However, causes and consequences of TRH in CKD patients remain incompletely understood. Therefore, we analyzed the prevalence of apparent TRH (aTRH), and phenotypic characteristics and prognosis associated with aTRH among participants of the German Chronic Kidney Disease (GCKD) study. As insufficient medication adherence has been shown to be a frequent cause of pseudoresistance, we also assessed treatment adherence. Study participants were classified as having aTRH, controlled hypertension and uncontrolled hypertension based on study visit blood pressure and self-reported medication intake. Drug adherence was assessed by comparing self-reported antihypertensive medication with detectable urinary drug metabolites measured by mass spectroscopy. Out of 4901 individuals included in this study, 38% were classified as having aTRH. Male sex, older age, lower estimated glomerular filtration rate (eGFR), higher body mass index (BMI), higher urine albumin-to-creatinine ratio (UACR) and presence of diabetes mellitus were independently associated with higher prevalence of aTRH in a multivariable adjusted regression model. Patients classified as aTRH had higher risk for major adverse cardiovascular events and worsening of kidney disease compared to patients with no aTRH after multivariate adjustment for potential confounders. There was a high agreement between self-reported medication and detectable urinary drug metabolites. In conclusion, in a cohort of Caucasian patients with moderately severe CKD, aTRH was highly prevalent and, in most cases, likely not caused by low medication adherence. Furthermore, aTRH was linked to cardio-renal endpoints, emphasizing the need for improved management.

Toxic nephropathy: Adverse renal effects caused by drugs

This is a brief overview of toxic nephropathy, which is an increasingly recognised problem with the continual introduction of new drugs and novel drug modalities, especially in oncology, and the risks associated with polypharmacy in many patients; although it is important to remember that it may not always be caused by a drug. It is also important to note that several possibly harmful drugs are now available without prescription ('over-the-counter') and can be purchased easily over the internet, including some poorly characterised herbal remedies. Knowing exactly what our patients are taking as medication is not always easy and patients often fail to mention drugs that may not have been prescribed by a doctor or recommended by a pharmacist. Moreover, patients with several comorbidities often require care from more than one doctor in other specialties, which can also lead to drug prescribing in isolation. This article will summarise some key aspects of drug nephrotoxicity and provide a few clinical pointers to consider, bearing in mind that there is rarely any antidote available, and effective treatment relies on early detection, prompt drug withdrawal, and supportive care. This short review is intended only as a primer to highlight some of the more practical aspects of toxic nephropathy; its content is based on a lecture delivered during the 2021 European Congress of Internal Medicine.