Familial risk of sinus node dysfunction indicating pacemaker implantation: a nationwide cohort study

Area of Science:

• Cardiology
• Genetics
• Public Health

Background:

• Sinus node dysfunction (SND) is a common indication for cardiac pacing.
• Genetic predisposition to SND is suspected but not well-established.

Purpose of the Study:

• To investigate the risk of SND and mortality in first-degree relatives of patients with SND requiring pacemakers.
• To assess the impact of the age of pacemaker implantation on disease risk in relatives.

Main Methods:

• Nationwide register-based study using Danish registries (Civil Registration, National Patient, Pacemaker and ICD).
• Followed 6,027,090 individuals born after 1954 (1982-2022).
• Analyzed 2,477 pacemaker implantations for SND.

Main Results:

• First-degree relatives had a 2.9-fold increased risk of pacemaker-treated SND compared to the general population.
• Risk was inversely proportional to the index person's implantation age (RR=5.5 for ≤60 years).
• Overall mortality was similar, but higher for relatives of early-onset SND patients (RR=1.22 for ≤60 years).

Conclusions:

• First-degree relatives of SND patients face an elevated risk of SND.
• The risk of SND in relatives is inversely associated with the age of pacemaker implantation in the index patient.
• While overall mortality is comparable, early-onset SND in a family member may increase mortality risk in relatives.