Parity, coronary heart disease and mortality in the old order Amish

Parity and later life risk for coronary heart disease among slum-dwelling women in Mysore, India

BACKGROUND

To examine the role of parity in coronary heart disease (CHD) among middle-aged Indian women living in government-designated slums in Mysore, India.

METHODS

Between October 2017 and May 2018, a cross-sectional study was carried out among women, 40-64 years of age, residing in government-designated slums in Mysore, India. In addition to socio-demographics, data were collected on CVD risk factors including use of tobacco and alcohol, diet, physical activity, sleep, quality of life, and personal and family history of chronic disease. Patients underwent a medical examination and a venous blood sample was taken for fasting lipid measurement. Resting electrocardiography was carried out by a trained medical technician. Multivariable logistic regression with associated 95% confidence intervals was used to examine the relationship between parity and coronary heart disease.

RESULTS

The prevalence of CHD in this sample of middle-aged women was 6.4%. Nulliparous women were at heightened risk for CHD compared to parous women with up to five live births. In the adjusted model, women who had 1-2 and 3-5 live births had 0.24 times lower odds (95% Confidence Interval [CI]: 0.05-1.29) and 0.38 times lower odds (95%CI: 0.178-0.87) of CHD, respectively, as compared to nulliparous women.

CONCLUSION

Among a fairly homogenous population of slum-dwelling women reporting almost universal breastfeeding for three or more months following birth, parity up to five births appeared protective against CHD. Further studies are needed to evaluate whether near universal breastfeeding rates in this population mediated the relationship of parity and CHD.

Gravidity, parity, blood pressure and mortality among women in Bangladesh from the HEALS cohort

OBJECTIVES

Despite a hypothesised connection of reproductive history with hypertension and mortality, the nature of this association is poorly characterised. We evaluated the association of parity and gravidity with blood pressure, hypertension and all-cause mortality.

DESIGN

Prospective cohort study.

SETTING

Health Effects of Arsenic Longitudinal Study cohort in rural Bangladesh.

PARTICIPANTS

There were 21 634 Bangladeshi women recruited in 2000-2002, 2006-2008 and 2010-2014 included in the present analysis.

METHODS

Reproductive history was ascertained through an interviewer-administered questionnaire at the baseline visit. Blood pressure was measured by a trained study physician following a standard protocol at the baseline visit. Vital status was ascertained at the biennial follow-up of study participants through June 2017. Linear and logistic regression models estimated the relationship between parity and gravidity with blood pressure and hypertension, respectively. Cox proportional hazards models estimated the relationship with all-cause mortality only among women aged >45 years.

RESULTS

Diastolic blood pressure was lowest in women with parity one (reference) and elevated in nulliparous women (adjusted % change=3.12; 95% CI 1.93 to 4.33) and women with parity >2 (adjusted % change=1.71; 95% CI 1.12 to 2.31). The associations with nulliparity were stronger for women aged >45 years. Similar association patterns were observed with hypertension. Further, in nulliparous women aged >45 years, 265 deaths (6.6%) were ascertained during the follow-up period (median follow-up time=8 years), and we observed suggestive elevated risks of all-cause mortality (adjusted HR 3.83; 95% CI 0.74 to 19.78). The relationships between reproductive history, blood pressure, hypertension and mortality were similar when modelling reproductive history as gravidity rather than parity.

CONCLUSIONS

For women in rural Bangladesh, nulliparity and nulligravidity appear to be associated with higher blood pressure and subsequent elevated risk of mortality.

Frailty: A cost incurred by reproduction?

Evolutionary theories of senescence, such as the ‘disposable soma’ theory, propose that natural selection trades late survival for early fecundity. ‘Frailty’, a multidimensional measure of health status, may help to better define the long-term consequences of reproduction. We examined the relationship between parity and later life frailty (as measured by the Frailty Index) in a sample of 3,534 adults aged 65 years and older who participated in the English Longitudinal Study of Ageing. We found that the most parous adults were the most frail and that the parity-frailty relationship was similar for both sexes. Whilst this study provided some evidence for a ‘parity-frailty trade-off’, there was little support for our hypothesis that the physiological costs of childbearing influence later life frailty. Rather, behavioural and social factors associated with rearing many children may have contributed to the development of frailty in both sexes.

Women's Reproductive History and Pre-Clinical Peripheral Arterial Disease in Late Life: The San Diego Population Study

Objective: Reproductive events have been linked with increased cardiovascular risk in women, but whether they are associated with pre-clinical peripheral arterial disease (PAD) has been understudied. We evaluated associations between reproductive factors and later-life ankle-brachial index (ABI), femoral artery intima-media thickness (fIMT), and femoral plaques. Methods: Cross-sectional analysis of 707 multiethnic women who participated in a follow-up exam of the San Diego Population Study in 2007-2011. To assess associations between reproductive factors (age at menarche, parity, age at menopause, surgical menopause, hormone therapy) with ABI, and Doppler ultrasound measurements of common and superficial fIMT, linear regression was used; for femoral plaque presence, logistic regression was used. Models were adjusted for age, race/ethnicity, and cardiometabolic factors. We tested interactions of reproductive factors with menopause type (natural vs. surgical). Results: Women were on average 71 years old, and 56% were non-Hispanic White. Reproductive factors were not associated with fIMT, femoral plaque presence, or ABI. There were significant interactions between menopause type (surgical vs. natural) and oral contraceptive use (-β: 0.04, p = 0.03) for ABI, as well as between menopause type and parity (β: 0.11, p = 0.05) and age at menopause (β: 0.001, p = 0.05) for fIMT. Among women with natural menopause, oral contraceptive use was associated with higher ABI (β: 0.03, p = 0.007) and older age at natural menopause was related to greater fIMT (β: 0.009, p = 0.06). Among women with surgical menopause, nulliparity was marginally associated with greater fIMT (β: 0.33, p = 0.07). Conclusions: Reproductive history may not be independently associated with later-life lower extremity atherosclerosis in women. Studies are necessary to confirm findings and examine pregnancy-related exposures in relation to pre-clinical PAD.

The Association Between Parity and Subsequent Cardiovascular Disease in Women: The Atherosclerosis Risk in Communities Study

Background: Previous studies are inconclusive on the relationship between parity and cardiovascular disease (CVD), with few evaluating multiple cardiovascular outcomes. It is also unclear if any relationship between parity and CVD is independent of breastfeeding. We examined the associations between parity and cardiovascular outcomes, including breastfeeding adjustment. Materials and Methods: Data were from 8,583 White and African American women, 45-64 years of age, in the Atherosclerosis Risk in Communities Study. Coronary heart disease (CHD), myocardial infarction (MI), heart failure, and strokes were ascertained from 1987 to 2016 by annual interviews and hospital surveillance. Parity and breastfeeding were self-reported. Cox proportional hazards regression estimated hazard ratios (HR) for the association between parity and cardiovascular outcomes, adjusting for baseline sociodemographic, clinical and lifestyle factors, and breastfeeding. Results: Women reported no pregnancies (6.0%), or having 0 (1.6%), 1-2 (36.2%), 3-4 (36.4%), or 5+ (19.7%) live births. During 30 years follow-up, there were 1,352 CHDs, 843 MIs, 750 strokes, and 1,618 heart failure events. Compared with women with 1-2 prior births, those with prior pregnancies and no live births had greater incident CHD (HR = 1.64, 95% confidence interval 1.14-2.42) and heart failure risk (1.46, 1.04-2.05), after adjustment for baseline characteristics. Women with 5+ births had greater risk of CHD (1.29, 1.10-1.52) and hospitalized MI (1.38, 1.13-1.69), after adjustment for baseline characteristics and breastfeeding. Conclusions: In a diverse U.S. cohort, a history of 5+ live births is associated with CHD risk, specifically, MI, independent of breastfeeding. Having a prior pregnancy and no live birth is associated with greater CHD and heart failure risk.