Association Between Composite Dietary Antioxidant Index and Endometriosis from NHANES 2001-2006: A Cross-Sectional...

To evaluate the association between Composite Dietary Antioxidant Index (CDAI) and the risk of endometriosis in American women.

The study adopted a cross-sectional design, incorporating 3862 women aged over 20 years, selected from the National Health and Nutrition Examination Survey (NHANES) dataset from 2001 to 2006. Six dietary antioxidants were taken into account in calculating CDAI. Endometriosis was determined based on self-report. To evaluate the association between CDAI and the risk of endometriosis, we employed models with multivariable logistic variables. For subgroup assessment in relation to CDAI, a stratified multivariate logistic regression model was utilized.

Among all participants, 273 participants (7.1%) were found to exhibit endometriosis. The preliminary analysis showed a reverse association between CDAI and the likelihood of endometriosis (odds ratio [OR] = 0.95; 95% confidence interval [CI]: 0.92~0.98). Upon full adjustment within the multivariable logistic regression, the ORs (95% CI) for endometriosis prevalence per unit increase in CDAI were estimated to be 0.96 (0.93~1). When the CDAI levels were divided into quartiles, it was found that the ORs for endometriosis with CDAI levels in Q2 (-2.131-0.023), Q3 (0.023-2.650), and Q4 (2.650-42.854) were 0.74 (0.52, 1.05), 0.76 (0.53, 1.1), and 0.53 (0.36, 0.79), respectively, compared to those with CDAI levels in Q1 (-7.151--2.131). We evaluated the association between CDAI and endometriosis using subgroups stratified by age, race/ethnicity, education level, body mass index (BMI), oral contraceptive, and menopausal status, revealing a substantial negative relationship.

In this cross-sectional study, increasing CDAI was proportionally associated with a reduced risk of endometriosis among American women, suggesting a diet high in antioxidants may play an important role in reducing the risk of endometriosis. The findings of NHANES data spanning 2001 to 2006 suggest that promoting antioxidant-rich diets could be an important prevention strategy for endometriosis.