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The following is a summary of “Association of waist circumference with long-term all-cause mortality and cardiac death in patients with a pacemaker: a retrospective study,” published in the April 2025 issue of BMC Cardiovascular Disorders by Li et al. 

This study aimed to evaluate the association between abdominal obesity and long-term clinical outcomes in patients implanted with a pacemaker, with particular focus on all-cause and cardiac-specific mortality. While BMI has traditionally been used to assess obesity-related risk, increasing evidence suggests that waist circumference may offer a more precise reflection of visceral adiposity and its impact on cardiovascular health.

The investigation was conducted as part of the SUMMIT Study, enrolling 492 patients who had received permanent pacemakers. Participants were stratified into three groups: abdominally obese, normal, and lean, based on their baseline waist circumference measurements, which were taken at the midpoint between the lowest rib and iliac crest following exhalation. Abdominal obesity was defined according to standard thresholds: WC ≥80 cm for men and ≥75 cm for women. The study’s primary endpoint was all-cause mortality, while cardiac death was designated as the secondary outcome. Patients were followed for an average of 67.2 ± 17.5 months.

Of the total cohort, 37.6% exhibited abdominal obesity at baseline, with an average waist circumference of 84.2 ± 12.7 cm. During the follow-up period, 71 patients (14.4%) died from any cause, and 24 patients (4.87%) experienced cardiac-related death. Patients who died had significantly higher WC compared to survivors (87.6 cm vs. 83.6 cm, P = 0.014), whereas no statistically significant difference in BMI was observed (23.6 vs. 23.5, P = 0.930).

Multivariate Cox regression analysis revealed that lean individuals, defined by WC below the obesity threshold, had a markedly reduced risk of both all-cause mortality ([HR] 0.188; 95%  [CI] 0.070–0.505; P = 0.001) and cardiac death (HR 0.097; 95% CI 0.012–0.792; P = 0.029) compared with those classified as abdominally obese.

Waist circumference, as an indicator of abdominal obesity, appears to be a more reliable predictor of long-term mortality in patients with pacemakers than BMI. Specifically, individuals with WC below 80 cm for men and 75 cm for women exhibited significantly lower risks of both all-cause and cardiac-specific mortality. These findings underscore the importance of incorporating waist circumference into routine risk assessments for patients requiring pacemaker therapy and highlight the need for targeted interventions addressing visceral fat to improve survival outcomes in this population.

Source: bmccardiovascdisord.biomedcentral.com/articles/10.1186/s12872-025-04671-2