Cardiovascular
Heterogeneity in the Association Between Endometriosis and Early-Onset Cardiovascular Disease by Systemic Inflammation: NHANES 1999–2006 Chidinma Oli* Chidinma Oli University of Florida
Background: Endometriosis is a chronic inflammatory condition associated with increased cardiovascular disease (CVD) risk, yet the role of systemic inflammation in shaping this association remains poorly understood. We examined whether systemic inflammation modifies the association between endometriosis and early-onset CVD among U.S. women.
Methods: We analyzed data from 5,309 women aged 20–54 years in the National Health and Nutrition Examination Survey (1999–2006). Endometriosis and early-onset cardiovascular disease (i.e., CVD before age 55) were based on self-reported physician diagnoses. Early-onset CVD included congestive heart failure, coronary heart disease, angina, myocardial infarction, or stroke. Systemic inflammation was characterized using high-sensitivity C-reactive protein [hs-CRP; low (<1 mg/L), moderate (1–3 mg/L) and high (>3mg/L)] and the systemic immune-inflammation index (SII; tertiles). Survey-weighted logistic regression was used to assess heterogeneity across inflammation levels, with stabilized inverse probability of treatment weighting (IPTW) to adjust for confounding.
Results: Among 5,309 women, 356 (7.06%) reported an endometriosis diagnosis and 152 (3.02%) early-onset CVD. After IPTW adjustment for age, body mass index, smoking, education, age at menarche, physical activity and race/ethnicity, endometriosis was associated with higher odds of early-onset CVD among women with high hs-CRP (prevalence odds ratio [POR] = 2.37, 95% CI: 1.50–3.74), but not among those with low or moderate hs-CRP levels (p-interaction= 0.24). Across SII strata, the strongest association was observed among women in the medium SII tertile (POR = 3.09, 95% CI: 1.55–6.16), with no associations in the low or high tertiles (p-interaction = 0.16).
Conclusion: The association between endometriosis and early-onset CVD showed heterogeneity across levels of systemic inflammation, with stronger associations observed at higher hs-CRP and intermediate SII levels.