Screening and treatment of diabetic nephropathy by primary care physicians

Microvascular Benefits of New Antidiabetic Agents: A Systematic Review and Network Meta-Analysis of Kidney Outcomes

CONTEXT

Diabetic kidney disease affects nearly one-third of US adults with prevalent type 2 diabetes mellitus (T2DM). The use of new antidiabetic medications in the prevention and treatment of diabetic kidney disease is a growing area of research interest.

OBJECTIVE

We sought to characterize the risk of developing a composite kidney outcome among patients receiving a new antidiabetic medication of the SGLT-2i, GLP-1ra, and DPP-4i drug classes.

METHODS

We conducted a systematic literature search in MEDLINE to identify randomized trials observing kidney safety endpoints associated with the use of new antidiabetic medications. Two independent reviewers selected the 7 eligible studies for analysis. Included studies were published between January 2013 and March 2020, conducted with adult participantss, published full-text in English, and observed composite kidney outcomes. A network meta-analysis was conducted within a Bayesian framework using a fixed-effects model with uninformative priors.

RESULTS

A qualitative assessment of transitivity was conducted to ensure similar distribution of potential modifiers across studies. Included studies were generally comparable in mean age, glycated hemoglobin A1c (HbA1c), and mean duration of T2DM at baseline.

MAIN CONCLUSIONS

Compared with placebo, dapagliflozin was associated with the greatest reduction in risk of developing the composite kidney outcome (hazard ratio 0.53; 95% credible interval, 0.43-0.66) followed by empagliflozin, canagliflozin, semaglutide, and liraglutide. Linagliptin did not show a significant reduction in risk of the outcome.

LIMITATIONS

This analysis was limited by the scarcity of data for kidney safety endpoints in large, randomized clinical trials. Although the heterogeneity statistic was low, there are slight differences in study design and baseline demographic characteristics across trials.

Retinal microvascular signs and risk of diabetic kidney disease in asian and white populations

The objective was to examine prospectively the association between retinal microvascular signs and development of diabetic kidney disease (DKD) in Asian and White populations. We analysed two population-based cohorts, composing of 1,221 Asians (SEED) and 703 White (WESDR) adults with diabetes. Retinal microvascular signs at baseline included vascular caliber (arteriolar—CRAE, and venular—CRVE) and diabetic retinopathy (DR). Incident cases of DKD were identified after ~ 6-year. Incident cases were defined based on eGFR in SEED and proteinuria or history of renal dialysis in WESDR. The incidence of DKD were 11.8% in SEED and 14.0% in WESDR. Wider CRAE in SEED (OR = 1.58 [1.02, 2.45]) and wider CRVE (OR = 1.69 [1.02, 2.80)) in WESDR were associated with increased risk of DKD. Presence of DR was associated with an increased risk of DKD in both cohorts (SEED: OR = 1.91 [1.21, 3.01] in SEED, WESDR: OR = 1.99 [1.18, 3.35]). Adding DR and retinal vascular calibers in the model beyond traditional risk factors led to an improvement of predictive performance of DKD risk between 1.1 and 2.4%; and improved classification (NRI 3 between 9%). Microvascular changes in the retina are longitudinally associated with risk of DKD.

Point-of-care urine albumin in general practice offices: effect of participation in an external quality assurance scheme

BACKGROUND

The Norwegian Quality Improvement of Primary Care Laboratories (Noklus) offers external quality assurance (EQA) schemes (EQASs) for urine albumin (UA) annually. This study analyzed the EQA results to determine how the analytical quality of UA analysis in general practice (GP) offices developed between 1998 (n=473) and 2012 (n=1160).

METHODS

Two EQA urine samples were distributed yearly to the participants by mail. The participants measured the UA of each sample and returned the results together with information about their instrument, the profession and number of employees at the office, frequency of internal quality control (IQC), and number of analyses per month. In the feedback report, they received an assessment of their analytical performance.

RESULTS

The number of years that the GP office had participated in Noklus was inversely related to the percentage of "poor" results for quantitative but not semiquantitative instruments. The analytical quality improved for participants using quantitative instruments who received an initial assessment of "poor" and who subsequently changed their instrument. Participants using reagents that had expired or were within 3 months of the expiration date performed worse than those using reagents that were expiring in more than 3 months.

CONCLUSIONS

Continuous participation in the Noklus program improved the performance of quantitative UA analyses at GP offices. This is probably in part attributable to the complete Noklus quality system, whereby in addition to participating in EQAS, participants are visited by laboratory consultants who examine their procedures and provide practical advice and education regarding the use of different instruments.

Filling the gap in CKD: The health care workforce and faculty development

Given limited resources, adding another chronic illness to the panoply of chronic disease care is problematic. Nevertheless, chronic kidney disease (CKD) is increasing in recognition and prevalence across the world, and a management strategy for this growing population is necessary. A diverse group of health care professionals interacts with patients with CKD and their family members, including nurses, nurse practitioners, dieticians, social workers, pharmacists, physicians, physical therapists, physician assistants, and public health workers. All these individuals have the opportunity to reinforce CKD management. This potentially would bring a broader health care workforce to bear on CKD, reducing the impact of the nephrology workforce shortage. To realize such a strategy, it is necessary to bolster CKD awareness and knowledge in the diverse health care workforce. A faculty development program that extends CKD awareness to existing health care workers also has the possibility of migrating into the learner curriculum in health professional schools. This approach would expand CKD education, creating a skilled diverse health care workforce.

Quality of care and attributable healthcare costs in diabetic hypertensive patients initiated on calcium antagonist therapy

BACKGROUND AND OBJECTIVE

Calcium antagonists (CAs) from two classes - dihydropyridine and non-dihydropyridine (DCAs and NDCAs, respectively) - are important add-on agents in goal blood pressure (BP) attainment. This study compared drug regimens to which DCAs or NDCAs had been added; for each class, BP reduction and healthcare costs were evaluated in a diabetic hypertensive population.

DESIGN, SETTING AND PATIENTS

This was a retrospective observational study using administrative claims data within two US health plans. Patients with diabetes mellitus (DM) and hypertension initiated on CA therapy between 1 January 2000 through 30 June 2002 were identified; the date the first CA prescription (CA-Rx) was filled in this period was labelled the index date. Inclusion required plan enrolment for 6 months pre- and 1 year post-index, no CA-Rx 6 months pre-index, and medication possession ratio >50% for 1 year post-index. Patients fell into either dihydropyridine or non-dihydropyridine study groups.

MAIN OUTCOME MEASURES AND RESULTS

For each group, costs (amounts allowed by plans, in US dollars; actual costs for 2000-2002) were calculated for resources attributable to DM/hypertension. A total of 5551 patients met eligibility criteria (NDCA = 1515; DCA = 4036). Most had been taking other antihypertensive medications: 86% and 76% in the DCA and NDCA groups, respectively. The NDCA group had lower annual attributable costs than the DCA group ($US1637 [95% CI $US1479, $US1813] vs $US1989 [95% CI $US1823, $US2170]; p < 0.004). A total of 313 medical charts were reviewed (DCA = 242, NDCA = 71). Both groups had similar pre-and post-index BP values; mean changes in systolic and diastolic BP were not statistically significant between groups. Only 22% of all patients attained the recommended systolic/diastolic BP goal of <130/80mm Hg, and <45% of patients were tested for proteinuria during the study period.

CONCLUSIONS

Patients initiated on an NDCA attained similar BP reductions compared with DCA at lower total healthcare costs. Opportunities exist for more aggressive management of BP and testing for proteinuria in DM patients with hypertension.

Endothelial dysfunction in geriatric diabetic patients: the role of microalbuminuria in elderly type 2 diabetic patients? A randomized controlled study

BACKGROUNDS/AIMS

Microalbuminuria is considered a marker of extensive endothelial dysfunction and is associated with excess of other cardiovascular risk factors. Our aim is to assess the importance of the presence of microalbuminuria in elderly diabetic patients.

METHODS

A total of 40 normotensive elderly type 2 diabetic patients of both genders with mean age >65 years were randomly included and were further subdivided according to the presence of persistent microalbuminuria into microalbuminuric and normoalbuminuric groups.

PATIENTS AND METHODS

All patients in both groups were subjected to thorough clinical and laboratory investigations including the assay of serum thrombomodulin (TM) and glycosylated hemoglobin level. Early-morning midstream urine samples were evaluated for levels of beta 2 microglobulin, alpha 1 microglobulin, TM, and N-acetyl-beta-D-glucosaminidase (NAG).

RESULTS

There was no significant difference between both groups regarding the clinical demographic characteristics. There were statistically significant higher values for glycosylated hemoglobin percentage, serum triglycerides and serum TM and urinary B2 microglobulin, urinary alpha 1 microglobulin, urinary NAG and urinary thrombomodulin in microalbuminuric group in comparison to normoalbuminuric group (P < 0.05).

CONCLUSION

Microalbuminuria is associated with markers of endothelial dysfunction in elderly normotensive type 2 diabetic patients. We recommend incorporation of periodic testing for microalbuminuria in this sector of patients.

Who is tested for diabetic kidney disease and who initiates treatment? The Translating Research Into Action For Diabetes (TRIAD) Study

OBJECTIVE

We examined factors associated with screening for albuminuria and initiation of ACE inhibitor or angiotensin receptor blocker (ARB) treatment in diabetic patients.

RESEARCH DESIGN AND METHODS

We conducted surveys and medical record reviews for 5,378 patients participating in a study of diabetes care in managed care at baseline (2000-2001) and follow-up (2002-2003). Factors associated with testing for albuminuria were examined in cross-sectional analysis at baseline. Factors associated with initiating ACE inhibitor/ARB therapy were determined prospectively.

RESULTS

At baseline, 52% of patients not receiving ACE inhibitor/ARB therapy and without known diabetic kidney disease (DKD) were screened for albuminuria. Patients > or =65 years of age, those with higher HbA(1c), those with cardiovascular disease (CVD), and those without hyperlipidemia were less likely to be screened. Of the patients with positive screening tests, 47% began ACE inhibitor/ARB therapy. Initiation of therapy was associated with positive screening test results, BMI > or =25 kg/m(2), treatment with insulin or oral antidiabetic agents, peripheral neuropathy, systolic blood pressure > or =140 mmHg, and CVD. Of the patients receiving ACE inhibitor/ARB therapy or with known DKD, 63% were tested for albuminuria.

CONCLUSIONS

Screening for albuminuria was inadequate, especially in older patients or those with competing medical concerns. The value of screening could be increased if more patients with positive screening tests initiated ACE inhibitor/ARB therapy. The efficiency of screening could be improved by limiting screening to diabetic patients not receiving ACE inhibitor/ARB therapy and without known DKD.

Medication dosing errors for patients with renal insufficiency in ambulatory care

BACKGROUND

Approximately 8.7 million (3%) Americans have various degrees of chronic renal insufficiency (CRI). Patients with CRI are susceptible to adverse drug events related to improper dose adjustment of drugs that are eliminated primarily unchanged through the kidney. Renal dosing errors are an important quality-of-care problem in the inpatient setting, yet little is known about dosing errors for patients with renal insufficiency in the outpatient setting.

METHODS

Electronic records were queried to identify patients with CRI (estimated creatinine clearance < 50 mL/min) who visited the ambulatory care clinic at least once from January 1, 2003 through December 31, 2003.

RESULTS

Of the total of 224 patients identified with CRI, 157 (70%) received one or more of 17 drugs with high rates of renal elimination. A total of 207 drugs requiring dose adjustment were prescribed to these patients, and 52 (25%) were prescribed at an inappropriately high dose. For 127 (57%) of the 224 patients, CRI was not documented. Patients with documented CRI were equally likely to be prescribed an inappropriately high dose of a target drug.

DISCUSSION

Incorrect dosing of medications among patients with CRI is common in the ambulatory care setting. Strategies for preventing medication dosing errors can target the prescribing and monitoring stages of pharmaceutical care.

Rapid microalbuminuria screening in type 2 diabetes mellitus: simplified approach with Micral test strips and specific gravity

BACKGROUND

Microalbuminuria is known to be a harbinger of serious complications in type 2 diabetes mellitus. Since medical intervention at the onset of microalbuminuria can be critical in reducing these adverse outcomes, it is widely agreed that type 2 diabetic patients should be screened for microalbuminuria. The purpose of the present study is to evaluate Micral test strips in conjunction with a urine specific gravity determination as a rapid and accurate method for detecting microalbuminuria in type 2 diabetic patients.

METHODS

In this prospective study, a total of 444 urine samples of type 2 diabetic patients were obtained from the ABCD study cohort for analysis. Urinary albumin concentrations were determined using Micral test strips and compared to results measuring albumin by the immunoturbidimetry method of timed collections. Urine specific gravity was measured by a standard urine dipstick.

RESULTS

The performance characteristics of the Micral test strips for detecting microalbuminuria (30-300 mg albumin/24 h) were adequate but not optimal: sensitivity 88%, specificity 80%, positive predictive value 69%, negative predictive value 92%. A concomitant specific gravity determination was useful in indexing the magnitude of false negative and false positive readings by the Micral test strips.

CONCLUSIONS

While the use of Micral test strips provides a rapid approach to detecting microalbuminuria in type 2 diabetic patients, this method has limitations. The simultaneous measurement of specific gravity is helpful in addressing some of the shortcomings of this screening test.

Cost-effective strategies in the prevention of diabetic nephropathy

A significant subgroup of patients with diabetes mellitus are predisposed to developing diabetic nephropathy and it is in this subgroup that other diabetes- related complications, and in particular greatly increased cardiovascular disease risk, are concentrated. The high personal, social and financial costs of managing end-stage renal failure and the other complications associated with diabetic nephropathy make a powerful case for screening and effective intervention programmes to prevent the condition or retard its progression. As major breakthroughs in finding genetic susceptibility factors remain elusive, screening efforts continue to be based on microalbuminuria testing, despite increasing recognition of its limitations as a positive predictor of nephropathy. Interventions have been extensively studied, but results remain conflicting. Economic evaluations of such screening and intervention programmes are essential for health planners, yet models of the cost/benefit ratio of such interventions often rely on a rather slim evidence base. Where economic models are developed, they are frequently based on those papers that propound the greatest clinical benefits of a given intervention, leading to a possible over-estimation of the advantages of the chosen approach. Furthermore, the benefits of even such generally accepted interventions as ACE inhibitor treatment are less firmly established than generally appreciated. Lifestyle interventions are instinctively attractive, but are by no means a low-cost option (as is often assumed by both medical professionals and politicians). This review critically assesses the evidence for clinical efficacy and economic benefit of microalbuminuria screening and interventions such as intensive glycaemic control, antihypertensive treatment, ACE inhibition and angiotensin receptor blockade, dietary protein restriction and lipid-modifying therapy. The various costs associated with diabetic nephropathy are so great that even expensive interventions may have a favourable cost/benefit ratio, provided they are truly effective.

Screening for chronic kidney disease: unresolved issues

End-stage renal disease is epidemic in the United States. As a measure to control this epidemic, it has been recommended that individuals who are at risk for CKD be tested for undetected kidney disease during routine health care encounters. There are generally accepted criteria against which screening recommendations for CKD control and prevention programs should be judged. If detection strategies are to be adopted for the screening of kidney disease, then CKD must represent a significant public health problem, be characterized by a clear natural history with a detectable asymptomatic period, outcomes should be improved by early treatment, and acceptable screening tests should be available. Health systems must provide adequate and appropriate follow-up medical care for individuals with newly detected CKD. Finally, the cost-effectiveness of screening needs to be demonstrated and the effectiveness of screening as a means of achieving reductions in CKD should be proven in randomized trials.

Impact of a program to improve adherence to diabetes guidelines by primary care physicians

OBJECTIVES

Previous studies have shown that primary care physician (PCP) adherence to diabetes guidelines is suboptimal. We sought to determine the state of diabetes care given by independently practicing PCPs in a rural county in Indiana and whether a multifaceted intervention targeting PCPs, patients, and the health care system would improve adherence to diabetes guidelines.

RESEARCH DESIGN AND METHODS

Baseline audits to assess adherence to diabetes guidelines were done on charts of the seven PCPs in the county. Audits were repeated after development of local consensus guidelines and feedback of baseline performance and after implementation of various interventions (practice aids, physician detailing, patient education sessions, and implementation of computerized individual meal planning).

RESULTS

Before any intervention, rates of adherence to guidelines were low (15% for foot exams, 20% for HbA(1c) measurement, 23% for eye exam referrals, 33% for urine protein screening, 44% for lipid profiles, 73% for home glucose monitoring, and 78% for blood pressure measurements). One year after development of local consensus guidelines and feedback of baseline performance, significant improvements were seen in blood pressure measurements (71 vs. 83%; P = 0.002), foot exams (19 vs. 42%; P < 0.001), HbA(1c) measurements (26 vs. 37%; P = 0.012), and PCP eye exams (38 vs. 46%; P = 0.043); a trend toward improvement was seen in referral to eye specialists (25 vs. 33%; P = 0.059). After a second year of multiple interventions, only blood pressure measurements (70 vs. 92%; P < 0.001) and foot exams (22 vs. 47%; P < 0.001) remained significantly improved; all other areas returned to rates indistinguishable from baseline.

CONCLUSIONS

In busy primary care practices lacking organizational support and computerized tracking systems, sustained improvements in diabetes care are difficult to attain using traditional physician-targeted approaches.

The cost-effectiveness of treating all patients with type 2 diabetes with angiotensin-converting enzyme inhibitors

BACKGROUND

Although guidelines recommend angiotensin-converting enzyme inhibitors for diabetic patients with microalbuminuria, this strategy requires that providers adhere to screening recommendations. In addition, the benefit of angiotensin-converting enzyme inhibitors in normoalbuminuric patients was recently demonstrated.

OBJECTIVE

To evaluate the cost-effectiveness of treating all patients with type 2 diabetes.

DESIGN

Markov model simulating the progression of diabetic nephropathy.

DATA SOURCES

Randomized trials estimating the progression of diabetic nephropathy with and without angiotensin-converting enzyme inhibitors.

TARGET POPULATION

Patients 50 years of age with newly diagnosed type 2 diabetes (fasting plasma glucose level > or = 7.8 mmol/L [140 mg/dL]).

TIME HORIZON

Lifetime.

PERSPECTIVE

Societal.

INTERVENTIONS

Patients received angiotensin-converting enzyme inhibitors, screening for microalbuminuria, or screening for gross proteinuria.

OUTCOME MEASURES

Lifetime cost, quality-adjusted life expectancy, and marginal cost-effectiveness.

RESULTS OF BASE-CASE ANALYSIS

Screening for gross proteinuria had the highest cost and the lowest benefit. Compared with screening for microalbuminuria, treating all patients was more expensive ($15240 and $14940 per patient) but was associated with increased quality-adjusted life expectancy (11.82 and 11.78 quality-adjusted life-years). The marginal cost-effectiveness ratio was $7500 per quality-adjusted life-year gained.

RESULTS OF SENSITIVITY ANALYSIS

Results were sensitive to the cost, effectiveness, and quality of life associated with angiotensin-converting enzyme inhibitor therapy, as well as age at diagnosis. The model was relatively insensitive to adherence with screening and costs of treating end-stage renal disease.

CONCLUSIONS

Treating all middle-aged diabetic patients with angiotensin-converting enzyme inhibitors is a simple strategy that provides additional benefit at modest additional cost. The strategy assumes that patients meet the older diagnostic criteria for diabetes and makes sense only for those who are not bothered by treatment.