IgA Nephropathy in Adults: A Review

Importance IgA nephropathy (IgAN) is a chronic kidney disease involving deposition of IgA-containing immune complexes in the glomerulus, causing glomerular inflammation and scarring. It is the most common immune-mediated glomerular disease worldwide, and affects an estimated 198 887 to 208 184 persons in the US. Up to 50% of patients with IgAN develop kidney failure within 10 years of diagnosis.

Observations IgAN typically presents with nephritic syndrome and usually occurs in younger adults, with a mean age at diagnosis of 34 to 45 years. Incidence is highest in East Asia. Approximately 60% of cases are detected incidentally with hematuria or proteinuria on urinalysis. Up to 30% of patients present with episodic visible hematuria, often concomitantly with an upper respiratory or gastrointestinal tract infection (synpharyngitic hematuria). Less common presentations include nephrotic syndrome (<5%) and rapidly progressive glomerulonephritis (<5%). When IgAN is suspected (due to hematuria, proteinuria, or reduced kidney function), initial workup should include quantification of proteinuria and assessment for other causes of nephritic syndrome (eg, lupus nephritis). Adults with suspected IgAN and proteinuria greater than or equal to 0.5 g per day should undergo kidney biopsy. The diagnosis of primary IgAN is based on presence of IgA-dominant immune deposits in the glomerular mesangium after excluding other causes of this histologic appearance, ie, IgA vasculitis, IgA-dominant infection-related glomerulonephritis, and secondary IgAN from diseases such as cirrhosis, inflammatory bowel disease, celiac disease, infection (eg, viral hepatitis), and autoimmune diseases (eg, axial spondyloarthritis). Based on the Kidney Disease: Improving Global Outcomes 2025 clinical practice guideline for the management of IgAN, treatment for patients with proteinuria greater than 0.5 g per day includes behavioral modifications (eg, dietary sodium <2 g/d, smoking cessation, weight control, exercise), antihypertensive medications for goal blood pressure less than 120/70 mm Hg, and therapies to reduce the formation of IgA-containing immune complexes (eg, targeted-release budesonide), decrease glomerular injury (eg, systemic glucocorticoids, iptacopan), and manage existing IgAN-induced nephron loss (eg, renin-angiotensin system inhibitor or dual endothelin angiotensin receptor antagonist [eg, sparsentan] alone or in combination with a sodium-glucose cotransporter 2 inhibitor).

Conclusions and Relevance IgAN is the leading cause of immune-mediated glomerular disease worldwide. Patients with suspected IgAN and proteinuria greater than or equal to 0.5 g per day should undergo kidney biopsy to confirm the diagnosis. Treatment of IgAN includes behavioral modifications, blood pressure management, and therapies to decrease formation of IgA-containing immune complexes (eg, targeted-release budesonide), reduce immune complex–mediated glomerular injury (eg, systemic glucocorticoids, iptacopan), and manage IgAN-induced nephron loss (eg, renin-angiotensin system inhibitor, dual endothelin angiotensin receptor antagonist, and sodium-glucose cotransporter 2 inhibitor).

Author/s:

Sinead Stoneman, Jia Wei Teh, Michelle Marie O’Shaughnessy

Revisiting Race and the Benefit of RAS Blockade in Heart Failure: A Meta-Analysis of Randomized Clinical Trials

Alex Haga — Thu, 27 Jun 2024 23:40:01 +0000

Date Added:

June 27, 2024

Journal/Publication:

JAMA

Publication Date:

June 25, 2024

URL:

Revisiting Race and the Benefit of RAS Blockade in Heart Failure: A Meta-Analysis of Randomized Clinical Trials

Type:

Meta-analyses, Reviews, and Guidelines

Format:

Article

DOI (1):

10.1001/jama.2024.6774

Keywords

RAS blocker

heart failure

renin-angiotensin system

PMID (1):

38809561

MeSH

Angiotensin Receptor Antagonists* / therapeutic use

Angiotensin-Converting Enzyme Inhibitors* / therapeutic use

Black or African American

Renin-Angiotensin System* / drug effects

Heart Failure* / drug therapy

RAS blockers work as well for CHF in Black people as in White people. James W. Mold, MPH

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Importance: Concerns have arisen that renin-angiotensin system (RAS) blockers are less effective in Black patients than non-Black patients with heart failure and reduced ejection fraction (HFrEF).

Objective: To determine whether the effects of RAS blockers on cardiovascular outcomes differ between Black patients and non-Black patients with HFrEF.

Data sources: MEDLINE and Embase databases through December 31, 2023.

Study selection: Randomized trials investigating the effect of RAS blockers on cardiovascular outcomes in adults with HFrEF that enrolled Black and non-Black patients.

Data extraction and synthesis: Individual-participant data were extracted following Preferred Reporting Items for Systematic Reviews and Meta-analyses Independent Personal Data (PRISMA-IPD) reporting guidelines. Effects were estimated using a mixed-effects model using a 1-stage approach.

Main outcome and measure: The primary outcome was first hospitalization for HF or cardiovascular death.

Results: The primary analysis, based on the 3 placebo-controlled RAS inhibitor monotherapy trials, included 8825 patients (9.9% Black). Rates of death and hospitalization for HF were substantially higher in Black than non-Black patients. The hazard ratio (HR) for RAS blockade vs placebo for the primary composite was 0.84 (95% CI, 0.69-1.03) in Black patients and 0.73 (95% CI, 0.67-0.79) in non-Black patients (P for interaction = .14). The HR for first HF hospitalization was 0.89 (95% CI, 0.70-1.13) in Black patients and 0.62 (95% CI, 0.56-0.69) in non-Black patients (P for interaction = .006). Conversely, the corresponding HRs for cardiovascular death were 0.83 (95% CI, 0.65-1.07) and 0.84 (95% CI, 0.77-0.93), respectively (P for interaction = .99). For total hospitalizations for HF and cardiovascular deaths, the corresponding rate ratios were 0.82 (95% CI, 0.66-1.02) and 0.72 (95% CI, 0.66-0.80), respectively (P for interaction = .27). The supportive analyses including the 2 trials adding an angiotensin receptor blocker to background angiotensin-converting enzyme inhibitor treatment (n = 16 383) gave consistent findings.

Conclusions and relevance: The mortality benefit from RAS blockade was similar in Black and non-Black patients. Despite the smaller relative risk reduction in hospitalization for HF with RAS blockade in Black patients, the absolute benefit in Black patients was comparable with non-Black patients because of the greater incidence of this outcome in Black patients.

Author/s:

Li Shen, Matthew M Y Lee, Pardeep S Jhund, Christopher B Granger, Inder S Anand