Preterm Birth Is Associated With Increased Blood Pressure in Young Adults: Important Opportunities for Blood Pressure Management

The co-occurrence and cumulative prevalence of hypertension, rheumatoid arthritis, and hypothyroidism in preterm-born women in the Women's Health Initiative

Emerging evidence suggests that preterm-born individuals (<37 weeks gestation) are at increased risk of developing chronic health conditions in adulthood. This study compared the prevalence, co-occurrence, and cumulative prevalence of three female predominant chronic health conditions - hypertension, rheumatoid arthritis [RA], and hypothyroidism - alone and concurrently. Of 82,514 U.S. women aged 50-79 years enrolled in the Women's Health Initiative, 2,303 self-reported being born preterm. Logistic regression was used to analyze the prevalence of each condition at enrollment with birth status (preterm, full term). Multinomial logistic regression models analyzed the association between birth status and each condition alone and concurrently. Outcome variables using the 3 conditions were created to give 8 categories ranging from no disease, each condition alone, two-way combinations, to having all three conditions. The models adjusted for age, race/ethnicity, and sociodemographic, lifestyle, and other health-related risk factors. Women born preterm were significantly more likely to have any one or a combination of the selected conditions. In fully adjusted models for individual conditions, the adjusted odds ratios (aORs) were 1.14 (95% CI, 1.04, 1.26) for hypertension, 1.28 (1.12, 1.47) for RA, and 1.12 (1.01, 1.24) for hypothyroidism. Hypothyroidism and RA were the strongest coexisting conditions [aOR 1.69, 95% CI (1.14, 2.51)], followed by hypertension and RA [aOR 1.48, 95% CI (1.20, 1.82)]. The aOR for all three conditions was 1.69 (1.22, 2.35). Perinatal history is pertinent across the life course. Preventive measures and early identification of risk factors and disease in preterm-born individuals are essential to mitigating adverse health outcomes in adulthood.

Association of Preterm Birth With Prevalent and Incident Hypertension, Early-Onset Hypertension, and Cardiovascular Disease in the Women's Health Initiative

Increasing evidence suggests preterm birth is a risk factor for hypertension and cardiovascular disease (CVD) in adulthood. Whether there is effect modification by hypertension on CVD risk is unknown. To investigate the associations between preterm birth, hypertension, and incident CVD, we identified 2,303 women aged 50 to 79 years who self-reported being born preterm from the Women's Health Initiative. Using multivariable logistic regression, prevalent hypertension at enrollment, age at hypertension diagnosis, and antihypertensive medication use were compared by birth status (preterm, full-term). Risk of incident hypertension, coronary heart disease, and CVD were analyzed using multivariable Cox proportional-hazard models. Both models adjusted for age, race/ethnicity, education, smoking, physical activity, body mass index, and diabetes mellitus. Significant associations were found between preterm birth and prevalent hypertension (37% vs 33.1%; adjusted odds ratio 1.26 [95% confidence interval (CI) 1.15 to 1.28] p = <0.0001), early-onset hypertension (<50 years) (14.7% vs 11.7%; adjusted odds ratio 1.31, 95% CI 1.15 to 1.48, p = <0.0001), and incident hypertension (53.2% vs 51%; ajusted hazard ratio 1.10, 95% CI 1.03 to 1.19, p = 0.008). Preterm-born women reported taking more antihypertensive medications (2.9% vs 2.6%, p = 0.04). Preterm birth had a nonsignificant association with CVD risk, but when stratified by prevalent hypertension, women born preterm without hypertension had elevated CVD risk compared with women born full-term without prevalent hypertension. Women with prevalent hypertension, preterm and full-term, had similar magnitudes of elevations in CVD risk. In conclusion, preterm birth increases the risk of hypertension and coronary heart disease. With 10% of the population born preterm, birth history should be assessed as a CVD risk factor.

Increased preterm birth following maternal wildfire smoke exposure in Brazil

Preterm birth (PTB) complications are the leading cause of death among children under 5 years of age, responsible for approximately 1 million deaths in 2015, according to the World Health Organization. Those infants born prematurely who survived the first 5 years, studies suggest that these infants are more likely to experience a range of poor health outcomes during childhood and even adulthood. Wildfire smoke has been suggested as a type of air pollution source with high toxicity for reproductive health. In this study, we estimated the association between preterm birth and wildfire periods in Brazil, a country included in the list of the 10 nations with the greatest number of preterm birth and also considered as a very fire-prone region. We applied a time-stratified case-crossover study design using conditional logistic regression models to estimate the odds ratio for preterm birth associated with wildfire-related prenatal PM_2.5, during different windows of exposure, including trimesters 1-3. After adjusting for several confounders (other air pollutants, demographics, meteorological variables, and spatiotemporal terms), we found that wildfire smoke exposure during pregnancy may be associated with preterm birth in Brazil. Southeast was the region with the highest increase in the odds of PTB (OR:1.41 (95%CI: 1.31-1.51) when the exposure occurred in the first trimester. In the North, exposure to PM_2.5 during wildfire periods in the second trimester of pregnancy was associated with increased odds of PTB (OR:1.05 (95%CI: 1.01-1.09) in preterm birth when the exposure occurred in the second trimester. This study suggests that wildfire smoke exposure during pregnancy may increase the risk for preterm birth in Brazil. This should be of great concern to the public health authorities, obstetricians, and policymakers.

Low birth weight trends: possible impacts on the prevalences of hypertension and chronic kidney disease

Worldwide, hypertension and chronic kidney disease (CKD) are highly prevalent disorders and are strong risk factors for cardiovascular disease and end-stage renal disease (ESRD). The developmental origins of health and disease (DOHAD) concept suggests that undesirable perinatal environmental conditions, such as malnutrition, contribute to disease development in adults. Among the known hypertension and CKD risk factors, DOHAD plays a potential role in determining susceptibility to the onset of these diseases in later adulthood. Since low birth weight (LBW) is a surrogate marker for adverse fetal environmental conditions, the high incidence of LBW in developing countries and its increasing incidence in most developed countries (attributed to multiple pregnancies and prepregnancy maternal factors, such as undernutrition, advanced maternal age, and smoking) is concerning. Thus, LBW is an important public health problem not only because of the associated infant mortality and morbidity but also because it is a risk factor for adult-onset hypertension/CKD. During their reproductive years, pregnant women who were born with LBWs have an increased risk of hypertensive disorders of pregnancy, which contribute to the risk of developing cardiovascular disease and ESRD. The offspring of LBW females are also likely to be LBW, which suggests that susceptibility to hypertension/CKD may reflect transgenerational inheritance. Therefore, there is global concern about the increasing prevalence of LBW-related diseases. This review summarizes the relevance of hypertension and CKD in conjunction with DOHAD and discusses recent studies that have examined the impact of the upward LBW trend on renal function and blood pressure.

Lower insulin sensitivity in young adults born preterm in Thailand

BACKGROUND

Previous studies reported impaired glucose homeostasis among preterm survivors, but consisted almost exclusively of Caucasians. It is unknown whether Asians born preterm display similar impairments.

AIM

To assess glucose homeostasis and other cardiometabolic outcomes among young adults born preterm in Thailand.

METHODS

Participants were 575 young adult offspring of mothers from the Chiang Mai Low Birth Weight Study, born in 1989 to 1990 and followed up in 2010: 54.1% females, median age 20.6 years, including 33 individuals (5.7%) born preterm. After an overnight fast, participants underwent clinical assessments, including blood sampling (glucose, insulin, and lipid profile). Insulin sensitivity was assessed using HOMA-IR and insulin secretion estimated using HOMA-β.

RESULTS

In unadjusted analyses, young Thai adults born preterm were 3.2 cm shorter (P = .037), 6 kg lighter (P = .016), and had HOMA-β 34% higher (P = .026) than those born at term. Adjusted analyses accounting for important confounders showed marked impairments in glucose homeostasis among preterm survivors: fasting insulin levels were 32% greater (P = .011), with HOMA-IR and HOMA-β that were 31% (P = .020) and 43% higher (P = .005), respectively, compared to peers born at term. There were no other contrasting observations between groups, with anthropometric differences disappearing after adjustment for confounders.

DISCUSSION

Young adults in Thailand born preterm were more insulin resistant than peers born at term. The observed impairments in glucose metabolism among young Thai adults born preterm corroborate findings reported mostly on Caucasians. The challenge for general practitioners and public health professionals is to encourage those born preterm to make healthier lifestyle choices early on.

Preterm Birth Is Associated With Increased Blood Pressure in Young Adults: Important Opportunities for Blood Pressure Management

See Article Skudder-Hill et al.