Cardiovascular Morbidities in Adults Born Preterm: Getting to the Heart of the Matter!

Abstract

Advances in perinatal and neonatal care have led to improved survival of preterm infants into adulthood. However, the shift in focus to long-term health in adults born preterm requires a clear understanding of the impact of prematurity on developing organ systems and the development of adult-oriented disease. A less well-recognized area of risk for surviving preterm infants is their cardiometabolic health. Epidemiologic evidence has linked preterm birth to the development of systemic hypertension, type 2 diabetes, metabolic syndrome, heart failure, and ischemic heart disease. Of more significant concern is that the risk of cardiometabolic disorders is higher in adults born preterm compared to full-term infants. The interconnected nature of the cardio-pulmonary system means worsening morbidity and mortality in adults born preterm. Addressing the problems of adults born preterm holistically would help promote cardiovascular health, wellness, and quality of life over their lifetime. Recognizing that adults born preterm are a unique subset of the population is a challenge in the current healthcare environment. Addressing issues relevant to adults born preterm in the clinically and research domain, using technology to characterize cardiopulmonary physiology and exercise tolerance, developing screening tools for early diagnosis and treatment, and robust follow-up of these infants with access to longitudinal data would improve both the quality and longevity of life in adults born preterm.

Keywords: adults born preterm; diabetes; heart failure; hypertension; ischemic heart disease; metabolic syndrome; prematurity.

Figure 1

Illustration of the pathophysiology of cardiovascular morbidities in adults born preterm. Alterations in the cardiac structure include a smaller RV or LV systolic or diastolic volume and an increase in RV or LV mass. Functional changes include systolic and diastolic dysfunction, hypercontractile heart, and low cardiac output. Metabolic syndrome and a higher risk of type II diabetes contribute to endothelial dysfunction leading to systemic hypertension and ischemic heart disease. In addition, the smaller diameter of the thoracic and abdominal aorta, lower nephron mass, and alterations in sodium balance with activation of the renin-angiotensin system all contribute to the development of systemic hypertension in adults born preterm. Abbreviations: BPD—bronchopulmonary dysplasia, RAD—reactive airway disease, COPD—chronic obstructive airway disease, O2—oxygen, CMC—cardiomyocyte, RV—right ventricle, LV—left ventricle, T2D—type II diabetes, JGA—juxtaglomerular apparatus, RAS—renin-angiotensin system, PH—pulmonary hypertension, ROS—reactive oxygen species, IHD—ischemic heart disease, LVSVI—Left Ventricular Systolic Volume Index, LVDVI—Left Ventricular Diastolic Volume Index (copyright: Vasantha Kumar. H.S).

Figure 2

Diaphragmatic representation of clinical morbidities seen following premature birth in adults born preterm. The interconnectedness of the cardiac and pulmonary systems means that the heart carries the brunt of the effects of pulmonary morbidity. Early onset of type 2 diabetes and metabolic syndrome are risk factors for ischemic heart disease and systemic hypertension in adulthood. Systemic and pulmonary hypertension and chronic lung disease (COPD) are risk factors for the development of cardiac failure. Pulmonary hypertension, reactive airway disease and COPD could trigger exercise intolerance in preterm-born adults. Abbreviations: RAD—reactive airway disease, COPD—chronic obstructive airway disease, T2D—type II diabetes, PH—pulmonary hypertension, IHD—ischemic heart disease. (copyright: Vasantha Kumar. H.S).

Figure 3

Screening, early diagnosis, and interventions that would improve the quality of life in adults born preterm. Maternal cigarette smoking and intrauterine growth retardation contribute adversely to fetal development. Optimal postnatal nutrition and maternal breast milk promotion may facilitate organ system growth patterns. Screening for metabolic syndrome, biomarkers for detection of heart failure, and pulmonary function tests for obstructive airway disease may help in the early diagnosis and management of comorbidities. Lifestyle changes to promote wellness are of particular importance in adults born preterm. The role of stem cells in promoting lung growth needs more studies. Abbreviations: BW—birth weight, GA—gestational age, MV—mechanical ventilation, BP—blood pressure, BNP—brain natriuretic peptide. (copyright: Vasantha Kumar. H.S).