Abstract 4140423: Advanced maternal age and association with major adverse cardiovascular events from NHANES from 1999 to 2018

Introduction: Pregnancy at an advanced age is becoming increasingly common in developed countries. The relationship between advanced maternal age (AMA) (≥ 35 years) and major cardiovascular events (MACE) is not well studied. Therefore, we evaluated the association of AMA at the time of last childbirth with MACE in a large nationally representative sample. Methods: We analyzed data from the 1999–2018 National Health and Nutrition Examination Survey. Females aged ≥45 years with no missing pregnancy record were included in the analysis. Based on the age of their last childbirth, they were divided into 4 groups- those who delivered at <35 years (GROUP 1), 35-40 years (GROUP 2), >40 years (GROUP 3), and nulliparous (GROUP 4). MACE was defined as a composite of a history of congestive heart failure, coronary artery disease, stroke, or all-cause death. We assessed the association between these groups and MACE using univariate and multivariate logistic regression models. Results: Among 13,180 (weighted frequency = 53,636,595) females included in this analysis, 20% had a history of AMA (groups 2 and 3), 70.6% had no history of AMA (group 1), and 9.4% were nulliparous. Compared to nulliparous women, women with no history of AMA had an 83% higher odd of MACE with an OR 1.83 (95% CI 1.45 – 2.31), while those with history of childbirth between ages 35 – 40 years had a 84% higher odd of MACE with OR of 1.84 (95% CI 1.37 - 2.46), and women with childbirth >40 had 2.7 higher odds of MACE (2.73, (1.87 - 4.00)). However, after adjusting for demographic characteristics and surrogates for social determinants of health such as income, food insecurity, and insurance status, as well as cardiovascular (CV) risk factors like alcohol use, smoking, and comorbidities such as diabetes, dyslipidemia, and hypertension, this association was attenuated. (Table 1) Conclusion: Our study did not find a significant independent association between the maternal age of last childbirth and MACE. This suggests that maternal age alone may not be the primary risk factor; the effect of AMA might be mediated by other CV, social risk factors, and parity. This warrants further investigation to better risk stratify women with AMA as a documented risk factor.