Impact of malnutrition on long-term atrial high-rate episodes, atrial fibrillation, and mortality in octogenarians with dual-chamber pacemakers

Background

Malnutrition is common among elderly patients, often leading to severe complications. This study sheds light on the connection between malnutrition and the occurrence of atrial high-rate episodes (AHREs) and atrial fibrillation (AF), as well as all-cause mortality, in individuals aged 80 and older (octogenarians) with dual-chamber permanent pacemakers (DCPM). We employed the Controlling Nutritional Status (CONUT) score and Prognostic Nutritional Index (PNI) to assess malnutrition status effectively.

Methods

In this comprehensive retrospective analysis, we evaluated 324 octogenarians who underwent DCPM implantation and received consistent long-term monitoring at a leading tertiary cardiac clinic. Participants were classified into three nutritional status categories based on their CONUT scores.

Results

During long-term follow-up, the incidence of AHREs did not differ significantly across CONUT score categories; however, AF and the combined endpoint of AHREs + AF were significantly higher in the moderate-to-severe malnutrition group (p < 0.001). Long-term mortality rates increased progressively from normal CONUT scores to moderate-to-severe scores. In the adjusted Cox model, mild malnutrition was associated with a 3.6-fold increased risk of mortality (95% CI: 2.2–14.2), while moderate-to-severe malnutrition conferred a 6.0-fold increased risk (95% CI: 3.4–20.4). Mortality risk rose consistently with worsening nutritional status, with multivariable-adjusted hazard ratios of 3.2 (95% CI: 1.6–11.6) and 5.4 (95% CI: 3.0–19.6) for mild and moderate-to-severe malnutrition, respectively. The CONUT score demonstrated superior predictive value compared with the PNI for both AHREs/AF (AUC 0.73 vs. 0.69) and all-cause mortality (AUC 0.67 vs. 0.61).

Conclusion

Malnutrition, as assessed by the CONUT score, is independently associated with long-term AHREs + AF and all-cause mortality in octogenarians undergoing standard pacemaker follow-up, with the CONUT score demonstrating greater predictive accuracy than the PNI.