Sarcoidosis Carries Higher Risk of Heart Failure, Study Suggests

Relative to the general population, people with sarcoidosis are at higher long-term risk of heart failure and other heart problems, a large Danish data study suggests.

Its researchers recommend regular monitoring of cardiac issues across this patient group.

The study, “Long-Term Adverse Cardiac Outcomes in Patients With Sarcoidosis,” was published in the Journal of the American College of Cardiology.

Sarcoidosis is characterized by the formation of granulomas (clumps of inflammatory cells) in different tissues and organs, most commonly in the skin, lungs, and lymph nodes. Some people with sarcoidosis will have involvement of the heart, which can lead to problems such as heart failure (when the heart is unable to efficiently pump blood).

Most published data on heart-related outcomes in sarcoidosis patients was either conducted several decades ago, or focused on relatively small populations. “There is a paucity of contemporary data on the risk of adverse cardiac outcomes, particularly heart failure, in patients with sarcoidosis,” the study noted.

Researchers used national health databases in Denmark to identify 11,834 adults diagnosed with sarcoidosis between 1996 and 2016. For each patient, they identified four people without sarcoidosis (control group), who were matched based by age, sex, and comorbidities (diseases apart from sarcoidosis).

The median age in the study population was 42.8, and 54.3% were male. Median follow-up time was just over eight years for both sarcoidosis patients and controls.

The absolute 10-year risk of heart failure was significantly higher among sarcoidosis patients than controls — 3.18% vs. 1.72%. The relative risk of heart failure in the sarcoidosis group was also seen to be particularly high in the first year after diagnosis.

“Sarcoidosis was associated with a higher long-term risk of incident [heart failure] compared with the background population,” the researchers wrote.

Other heart-related complications were also more common in sarcoidosis patients than in controls. In particular, the absolute 10-year risk of cardiac arrest, ventricular arrhythmias (abnormal heartbeats originating in the heart’s ventricles), and the need for an implantable cardioverter defibrillator was 0.96% for sarcoidosis patients and 0.45% for controls.

“Our study demonstrated that sarcoidosis was associated with a higher long-term risk of a wide range of cardiac
outcomes compared with a matched population,” the researchers wrote.

To better understand the prognosis of sarcoidosis-associated heart failure, the researchers matched 364 people with sarcoidosis who developed heart failure with patients with heart failure but without sarcoidosis (1,456 patients).

Statistical analyses indicated that the all-cause mortality risk was significantly higher — by about 35% — in the sarcoidosis group.

“Patients with sarcoidosis developing HF [heart failure] had a higher associated mortality than patients with HF without a history of sarcoidosis,” the researchers wrote.

Collectively, these “results underline the need for regular monitoring of cardiac manifestations in patients with sarcoidosis,” the team concluded.

Given the observational nature of this study, its researchers noted that it is not possible to draw reliable conclusions about cause and effects. Additionally, data used were incomplete in some aspects; for instance, it did not include information about individuals’ ethnicity, which is known to influence the prevalence and presentation of sarcoidosis. Diagnoses given a majority of the analyzed patients (57.3%) also did not specify the sarcoidosis location, and some may have had cardiac sarcoidosis, or sarcoidosis that specifically affects the heart.

Further studies are needed, they advised.

“These findings warrant further large-scale studies on the risk and prognosis associated with adverse cardiac outcomes in patients with sarcoidosis, including patients with confirmed cardiac sarcoidosis,” the researchers concluded.