Takahashi S; Department of Cardiology, Sakakibara Heart Institute
Nakayama A; Nanasato M; Isobe M

Environmental Health & Preventive Medicine. 31:26, 2026.

BACKGROUND: Although marital status is a key social determinant of health,
its prognostic relevance in cardiopulmonary exercise testing (CPX) cohorts
remains unclear. We aimed to evaluate the association between marital
status and mortality risk in patients with cardiac disease (CD) who
underwent CPX.

METHODS: This retrospective, single-center observational study involved
consecutive patients with CD who underwent post-discharge CPX between 2008
and 2020. Participants (mean age: 69 years; 73% male) were categorized as
either unmarried (never married, divorced, or widowed) or married. The
primary outcome was all-cause mortality, and the secondary outcome was
cardiovascular mortality. We used Cox proportional hazards models to
estimate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs).
Model 1 was adjusted for age and sex to estimate the overall association
between marital status and outcomes. Model 2 was adjusted for Model 1
covariates and peak VO2 to account for objectively measured exercise
capacity.

RESULTS: Of 4,681 patients analyzed, 1,117 were unmarried and 3,564 were
married. In Model 1, being married was associated with a lower risk of
all-cause mortality (aHR: 0.75, 95% CI: 0.62-0.91, P < 0.001). This
association persisted after adjusting for peak VO2 in Model 2 (aHR: 0.79,
95% CI: 0.65-0.96, P = 0.002). For cardiovascular mortality, the estimates
were consistent in direction (Model 1; aHR: 0.64, 95% CI: 0.44-0.93, P =
0.019, Model 2; aHR: 0.69, 95% CI: 0.47-1.02, P = 0.061).

CONCLUSIONS: In a large CPX cohort of patients with CD, married status
was associated with a lower risk of all-cause mortality. The association
was attenuated but remained after adjustment for peak VO2, suggesting that
differences in exercise capacity may contribute but do not fully account
for the observed association. Marital status should be interpreted as a
social marker rather than a causal or interventional exposure, and future
studies should clarify modifiable factors related to prognosis.