TOPLINE:

In a nationwide cohort of Japanese working-age adults, new-onset atrial fibrillation was associated with a modestly faster annual decline in kidney function — measured as a decrease of 0.29 mL/min/1.73 m² in the estimated glomerular filtration rate (eGFR) — and a higher risk of experiencing a 30% or greater reduction in the eGFR. The effects were more pronounced in women and patients with diabetes and when atrial fibrillation persisted at follow-up.

METHODOLOGY:

• Atrial fibrillation is sometimes found incidentally in working-age adults, but it is unclear whether it speeds up decline in kidney function.
• Researchers conducted a retrospective cohort study using data from annual health screening records (serial ECG and eGFR measurements) and insurance claims from a Japanese database to investigate the association of new-onset atrial fibrillation with subsequent decline in kidney function among working-age adults.
• They analyzed data of 141,060 adults (mean age, 49.8 years; 81.8% men) with normal sinus rhythm who did not have prior atrial fibrillation, cardiovascular comorbidities, or end-stage kidney disease.
• Those who developed new-onset atrial fibrillation during an exposure period of 1 year (n = 23,510) were each matched with five similar individuals who did not (n = 117,550).
• The primary outcome was decline in eGFR, and the secondary outcome was at least a 30% decline in eGFR from baseline; the median follow-up duration was 4.73 years, with a median of five eGFR measurements per participant.

TAKEAWAY:

• Developing new-onset atrial fibrillation was associated with a greater annual rate of decline in eGFR (difference, -0.29 mL/min/1.73 m²; P for interaction < .001) than not developing the condition.
• Individuals with new-onset atrial fibrillation had nearly triple the risk of experiencing a 30% or greater drop in eGFR (hazard ratio, 2.91; P < .001); the estimated 7-year risk was 11.0% with atrial fibrillation vs 4.9% without.
• Among individuals with atrial fibrillation confirmed during outpatient visits, those with reconfirmed atrial fibrillation at subsequent annual screening had a greater adjusted annual decline in eGFR (-1.55 mL/min/1.73 m²) than those who returned to sinus rhythm (-1.15 mL/min/1.73 m²; P < .001).
• Subgroup analyses revealed that the association between new-onset atrial fibrillation and accelerated decline in eGFR was more pronounced in women and patients with diabetes.

IN PRACTICE:

“This finding suggests the importance of CKM [cardiovascular-kidney-metabolic] perspectives in AF [atrial fibrillation] management,” the authors wrote.

SOURCE:

The study was led by Yuichiro Mori, MD, Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan. It was published online on in JAMA Network Open.

LIMITATIONS:

Unmeasured confounders such as detailed measurements (ambulatory blood pressure, medication classes and dosages, glycemic control, and sleep apnea), socioeconomic status, and lifestyle factors could not be fully accounted for. Atrial fibrillation identification based on annual screening ECGs and outpatient visits may have misclassified some individuals with paroxysmal and asymptomatic disease. The study population comprised Japanese citizens, and findings may not be generalizable to other regions.

DISCLOSURES:

This study received funding from the Japan Health Insurance Association and was also supported by AMED and JSPS KAKENHI. Two authors disclosed receiving consultation fees and grants outside the submitted work.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.