| Literature DB >> 35790319 |
Janet B McGill1, Hermann Haller2, Prabir Roy-Chaudhury3,4, Andrea Cherrington5, Takashi Wada6, Christoph Wanner7, Linong Ji8, Peter Rossing9,10.
Abstract
Albuminuria is useful for early screening and diagnosis of kidney impairment, especially in people with pre-diabetes or type 2 diabetes (T2D), which is the leading cause of chronic kidney disease (CKD) and end-stage kidney disease (ESKD), associated with increased mortality, poor cardiovascular outcomes, and high economic burden. Identifying patients with CKD who are most likely to progress to ESKD permits timely implementation of appropriate interventions. The early stages of CKD are asymptomatic, which means identification of CKD relies on routine assessment of kidney damage and function. Both albuminuria and estimated glomerular filtration rate are measures of kidney function. This review discusses albuminuria as a marker of kidney damage and cardiorenal risk, highlights the importance of early screening and routine testing for albuminuria in people with T2D, and provides new insights on the optimum management of CKD in T2D using albuminuria as a target in a proposed algorithm. Elevated urine albumin can be used to detect CKD in people with T2D and monitor its progression; however, obstacles preventing early detection exist, including lack of awareness of CKD in the general population, poor adherence to clinical guidelines, and country-level variations in screening and treatment incentives. With albuminuria being used as an entry criterion and a surrogate endpoint for kidney failure in clinical trials, and with novel treatment interventions available to prevent CKD progression, there is an urgent need for early screening and diagnosis of kidney function decline in people with T2D or pre-diabetes. © Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Entities:
Keywords: diabetes mellitus, type 2; diabetic neuropathies
Mesh:
Substances:
Year: 2022 PMID: 35790319 PMCID: PMC9258490 DOI: 10.1136/bmjdrc-2022-002806
Source DB: PubMed Journal: BMJ Open Diabetes Res Care ISSN: 2052-4897
Figure 1Prognosis of CKD by GFR and albuminuria categories. Green: low risk (if no other markers of kidney disease, no CKD); yellow: moderately increased risk; orange: high risk; red: very high risk. Reproduced with permission from Kidney Disease: Improving Global Outcomes (KDIGO) 2020 Clinical Practice Guideline for Diabetes Management in Chronic Kidney Disease.1 A, albuminuria category; CKD, chronic kidney disease; G, GFR category; GFR, glomerular filtration rate.
Figure 2Life expectancy in people with early CKD, T2D, and early CKD in T2D. The reference group consisted of participants with neither diabetes nor CKD. Early CKD was defined as CKD stages 1–3 without diabetes. Diabetes was defined as T2D without CKD. Early CKD in T2D was defined as diabetes with early CKD stages 1–3. Reproduced with permission from Kidney International.26 CKD, chronic kidney disease; T2D, type 2 diabetes.
Figure 3Proposed algorithm for the optimum management of CKD in T2D using albuminuria as a target.2 65 †Exercise (strenuous exercise within 24 hours of sample collection), infection (septicemia or other conditions increasing vascular permeability, symptomatic urinary tract infection), fever, congestive heart failure, marked hyperglycemia, menstruation, upright posture (orthostatic proteinuria causing transient elevation in UACR), and marked hypertension may elevate UACR independent of kidney damage. A, albuminuria category; ACEi, ACE inhibitor; ARB, angiotensin receptor blocker; CKD, chronic kidney disease; DPP-4i, dipeptidyl peptidase-4 inhibitor; eGFR, estimated glomerular filtration rate; G, GFR category; GLP-1RA, glucagon-like peptide-1 receptor agonist; RAS, renin–aldosterone system; SGLT2i, sodium-glucose co-transporter-2 inhibitor; T2D, type 2 diabetes; UACR, urine albumin-to-creatinine ratio.
Methods for testing albuminuria as recommended by KDIGO and ADA guidelines2 11 54 57
| Method | Urine albumin-to-creatinine ratio; screening*† | Urine albumin (24-hour urine albumin test) | Urine dipsticks sensitive for albuminuria‡ | Total protein measurements (urine protein-to-creatinine ratio)§ |
| Pros |
Guideline-preferred method. Capable of specific and precise quantification at low concentrations and of producing quantitative results over the clinically relevant range. Provides a more specific and sensitive measure of changes in glomerular permeability than urinary total protein. |
Capable of specific and precise quantification at low concentrations, and of producing quantitative results over the clinically relevant range. |
Convenient. Less expensive. |
Less expensive. |
| Cons |
Measurement may be influenced by several factors;¶ therefore, repeat tests are required, with 2 of 3 abnormal measurements reported within a period of 3–6 months before a patient is considered to have high albuminuria ( |
Method may be burdensome and time consuming and adds little to prediction or accuracy. Measurement may be influenced by several factors;¶ therefore, repeat tests are required, with 2 of 3 abnormal measurements reported within a period of 3–6 months before a patient is considered to have high albuminuria ( |
Method of measuring albumin alone. Measurement of albumin alone without simultaneously measuring urine creatinine is susceptible to false-negative and false-positive determinations as a result of variation in urine concentration due to hydration. Simultaneous measurement of creatinine allows more accurate results. |
Do not give equal analytical specificity and sensitivity for all proteins that can contribute to diverse estimates of proteinuria prevalence. Not as specific or sensitive a measure of changes in glomerular permeability as UACR, thus not as accurate in detecting low concentrations of albumin indicative of the early stages of kidney damage or kidney disease progression. |
*Screening, as measured by a spot urine sample, is done annually; however, patients with UALB >30 mg/g creatinine or an eGFR <60 mL/min/1.73 m2 should be monitored twice annually to guide therapy.11
†Albumin is measured using immunologic assays by diagnostic laboratories and albumin concentration reported as a ratio to urinary creatinine concentration (mg/mmol or mg/g).11
‡Urine dipstick test results may vary depending on the manufacturer and are affected by the urine pH. The results are also operator dependent and may be affected by colored compounds in urine (ie, bilirubin and drugs such as ciprofloxacin, chloroquine). This test cannot reliably distinguish between proteinuria categories and has a low diagnostic accuracy for proteinuria detection.2
§Most laboratories use either turbidimetric or colorimetric methods to measure total protein.2
¶Exercise (strenuous exercise within 24 hours of sample collection), infection (septicemia or other conditions increasing vascular permeability, symptomatic urinary tract infection), fever, congestive heart failure, marked hyperglycemia, menstruation, upright posture (orthostatic proteinuria causing transient elevation in UACR), and marked hypertension may elevate UACR independent of kidney damage.11
ADA, American Diabetes Association; eGFR, estimated glomerular filtration rate; KDIGO, Kidney Disease: Improving Global Outcomes; UACR, urine albumin-to-creatinine ratio; UALB, urine albumin.