Association of composite dietary antioxidant index with prevalence of stroke: insights from NHANES 1999-2018

Abstract

Background: There is a growing acknowledgment of the potential influence of antioxidative effects resulting from dietary decisions on the occurrence of stroke. The objective of this study was to elucidate the correlation between the composite dietary antioxidant index (CDAI) and the incidence of stroke in the general population of the United States.

Methods: We gathered cross-sectional data encompassing 40,320 participants from the National Health and Nutrition Examination Survey (NHANES) spanning the years 1999 to 2018. Employing weighted multivariate logistic regression, we assessed the correlation between CDAI and stroke, while also investigating potential nonlinear relationships through restricted cubic spline (RCS) regression. Further, the intake of CDAI components were then incorporated into a predictive nomogram model, subsequently evaluated for its discriminatory prowess in stroke risk assessment using the receiver operating characteristic (ROC) curve.

Results: Post-adjustment for confounding variables, we found that higher CDAI score were associated with a decreased risk of stroke, the odds ratio (OR) [95% CI] of CDAI associating with prevalence was 0.96 [0.94-0.98] (P< 0.001). Moreover, the adjusted OR [95% CI] for stroke across ascending CDAI quartiles stood at 0.90 [0.74-1.09], 0.74 [0.60-0.91], and 0.61 [0.50-0.76] compared to the reference quartile, respectively. The RCS analysis indicated a nonlinear yet negative correlation between CDAI and stroke. The nomogram model, constructed based the intake of antioxidants, exhibited a significant predictive capacity for stroke risk, boasting an area under the curve (AUC) of 77.4% (76.3%-78.5%).

Conclusion: Our investigation ascertained a nonlinear negative relationship between CDAI and stroke within the broader American population. However, given the inherent limitations of the cross-sectional design, further comprehensive research is imperative to establish the causative nature of this association.

Keywords: CDAI; NHANES; RCS; cross-sectional study; stroke.

Figure 1

A detailed flow chart of participant recruitment.

Figure 2

The RCS curve of the association between CDAI and stroke among all the study participants. RCS regression was adjusted for age, sex, race, education levels, smoking, drinking, hypertension, and DM. RCS, restricted cubic spline; CDAI, composite dietary antioxidant index; DM, diabetes; OR, odds ratio.

Figure 3

The RCS curves of the association between CDAI components and stroke among all the study participants. (A) The RCS curve of the association between carotenoid and stroke; (B) The RCS curve of the association between selenium and stroke; (C) The RCS curve of the association between zinc and stroke; (D) The RCS curve of the association between Vitamin A and stroke; (E) The RCS curve of the association between Vitamin C and stroke; (F) The RCS curve of the association between Vitamin E and stroke. RCS regression was adjusted for age, sex,race, education levels, smoking, drinking, hypertension, and DM. RCS, restricted cubic spline; CDAI, composite dietary antioxidant index; DM, diabetes; Se, selenium; OR, odds ratio.

Figure 4

Subgroups analyses for the association between CDAI and stroke. Analyses were stratified by sex (male and female), age (≤ 40 years, 40–60 years, and ≥ 60 years), race/ethnicity (Black, White, and others), and BMI (normal weight, overweight, and obesity). Logistic regression analyses were adjusted for age, sex, race, education levels, smoking, drinking, hypertension, and DM. CDAI, composite dietary antioxidant index; DM, diabetes; OR, odds ratio.

Figure 5

Subgroups RCS analyses for the association between CDAI and stroke stratified by (A) sex (male and female), (B) age (≤ 40 years, 40–60 years, and ≥ 60 years), and (C) BMI (normal weight, overweight, and obesity), and (D) race/ethnicity (Black, White, and others). RCS regression was adjusted for age, sex, race, education levels, smoking, drinking, hypertension, and DM. RCS, restricted cubic spline; CDAI, composite dietary antioxidant index; DM, diabetes; OR, odds ratio.

Figure 6

Establishment and validation of a risk prediction model for stroke. (A) A nomogram model based on age, race/ethnicity, and CDAI components. (B) ROC curve for evaluating the predictive power for stroke of the nomogram model. CDAI, composite dietary antioxidant index; ROC, receiver operating characteristic. * P value<0.05, ** P value<0.01, *** P value<0.001.