Patients with polycystic kidney disease (PKD) are at elevated risk of new-onset atrial fibrillation (AF), according to researchers.

In a population-based cohort study using inpatient claims data from Taiwan’s National Health Insurance Research Database (NHIRD), investigators found that PKD patients had a  significant 31% increased risk of AF compared with individuals who did not have PKD, after adjusting for age, sex, and comorbidities. The risk was higher in patients aged 50 to 64 years and those without any comorbidities, “suggesting that the development of AF in patients with PKD is highly associated with the disease itself,” the investigators reported in Medicine (2016;95:e2623).

The study by Tung-Min Yu, MD, of the China Medical University in Taiwan, and colleagues compared 7,203 PKD patients with 28,739 randomly selected controls frequency matched according to age, sex, and baseline comorbidities. The risk of AF in PKD patients increased as the number of risk factors increased. Compared with patients with no risk factors, those with 1 risk factor had a significant 59% increased risk of AF. Patients with 3 risk factors had a significant 67% increased risk. Patients with 4 and 5 or more risk factors had a 2.2 and 3.6 times increased risk, respectively.

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PKD patients with congestive heart failure (CHF) and chronic kidney disease (CKD) had the highest risk of AF, followed by PKD patients with hypertension and CHF, and PKD patients with hypertension, CHF, and CKD, according to the researchers. In addition, the odds of dying from AF was 69% higher in the PKD patients than in the comparison cohort.

“The current study is the first to provide clinical evidence of the association between AF and PKD,” the authors wrote.

Previous research has identified crucial risk factors associated with new-onset AF, including advanced age, hypertension, and CHF.

Cardiovascular complications remain the major problems contributing to mortality and morbidity in PKD patients, the researchers stated. Studies have demonstrated that enlargement of renal cysts in adults with ADPKD is associated with increased circulating and intrarenal renin-angiotensin-aldosterone system (RAAS) activity, Dr. Yu’s team noted. A study published in the American Journal of Nephrology (1998;18:391-398) revealed enhanced sympathetic activity in ADPKD patients, with higher plasma concentrations of epinephrine and norepinephrine found in patients with essential hypertension, with or without renal failure. In addition, in a paper published in Journal of Molecular and Cellular Cardiology (2013;58:199-208), researchers reported that idiopathic dilated cardiomyopathy was more prevalent in ADPKD patients than in the general population.

Neera K. Dahl, MD, PhD, Associate Professor of Medicine (Nephrology) at the Yale School of Medicine in New Haven, Conn., who has a research interest in ADPKD but was not part of the new study, said the paper by Dr. Yu and colleagues “provides evidence that ADPKD is an independent risk factor for AF.”

A limitation of the study, however, was the lack of information on structural heart disease in the cohort, Dr. Dahl said. It is not known if patients with PKD were more likely to have left ventricular hypertrophy, reduced ejection fraction, or valvular heart disease, which may also predispose to AF, and whether the findings from the Taiwanese population would be generalizable to other populations.

Cardiovascular disease is still the major cause of mortality in ADPKD.  Focusing on arrhythmia opens new areas for research,” Dr. Dahl said.