Can Nurturing the Young Be the Key to Tackling Chronic Diseases in the Old? A Narrative Review With a Global Perspective

INFANT AND CHILD HEALTH IN THE MILLENNIUM DEVELOPMENT GOALS ERA

The world’s children are living, growing, and learning more than ever before, but progress has not been the same across the globe and has fallen short of the global Millennium Development Goal (MDG) targets for childhood mortality, underweight, and primary education (Table 1).¹¹ Huge disparities still exist between HICs and LMICs. For example, sub-Saharan African children are more than 15 times more likely to die before their fifth birthday than children in HICs.¹² In LMICs, children born in the poorest families are twice as likely to die as those from the wealthiest.¹² This disparity is not restricted to the developing world. In HICs, disadvantaged populations suffer disproportionately. Babies born to indigenous Australian mothers and, in the United States, babies born to African American mothers are twice as likely to start life with low birth weight (a risk factor for neonatal death and childhood illness) than those born to nonindigenous and white non-Hispanic women. Additionally, babies born in remote communities or to mothers in the lowest socioeconomic classes are also at a disadvantage in both countries.^11,13,14

IMPORTANCE OF A GOOD START IN LIFE

Awareness is growing that the MDGs have not adequately captured the full burden of childhood health and development. The Sustainable Development Goals (SDGs), which succeeded the MDGs from 2015, established 17 broader and ambitious targets addressing economic, social, and environmental dimensions of development in an integrated manner.¹⁵ The SDG framework adopts a holistic perspective of health in the early years. It measures whether children thrive to their full potential by ensuring they are well-nourished and grow; are educated early and protected from threats; and grow up in a clean, healthy environment free from poverty (Table 2).¹⁶ In 2010, 43% of children in LMICs were at risk of not reaching their development potential because of stunting (ie, chronic malnutrition) and poverty.^17,18 The burden on children in HICs remains unclear.¹⁹ For example, while the United States performs well on childhood mortality and stunting, no nationally representative data on early childhood learning and protection from abuse and violence are available.¹⁶

Investing in nurturing care that addresses these risk factors gives children a good start in life and has enduring benefits on health, learning, and earning capacity²⁰ with the potential to address the comorbid negative effects of chronic disease and socioeconomic disadvantage. Fetal life, infancy, and early childhood are times of rapid brain growth; development of cognitive, language, and emotional capacities²¹; and establishment of long-term control of metabolism.²² Consequently, these are also times of extreme vulnerability to the effects of poor nutrition and psychosocial stressors.

In terms of nutrition, the first 1,000 days of life, from conception until 2 years of age, are critical. Poor maternal health and poor nutrition before and during pregnancy increase the risk of intrauterine growth restriction²³ that in turn increases the risk of stunting (or being short for your height, indicating chronic undernutrition).²⁴ Poor feeding practices and infectious disease also contribute to stunting, a condition that is irreversible after the first 2 years of life.^23,25 Undernutrition in the first 1,000 days increases the chances of becoming overweight in adulthood and of developing chronic disease risk factors such as high blood sugar, cholesterol, and blood pressure, especially if children rapidly gain weight after 2 years old.²⁴ Early undernutrition is also associated with lower educational attainment and adult income,^25,26 as well as restricted reproductive outcomes, as stunted women give birth to smaller babies.²⁷ Stunting and poverty in early life are estimated to reduce adult income by up to 20%.²⁸

Similarly, exposure to adverse experiences such as violence and poverty in early life is associated with a greater incidence of chronic disease (mental and physical) and lower education and income levels, especially when multiple risks accrue before 3 years of age.^18,20,29,30 The evidence is the strongest for the increased risk of cardiovascular disease and its contributing factors (eg, hypertension, diabetes, obesity),³⁰ a leading cause of adult morbidity and mortality in both high- and low-income countries. Poverty affects cognitive development directly through altered epigenetic and biological mechanisms^20,31,32 and indirectly because parents have fewer caregiving resources.³³ The effects of poverty on development are evident in the first 1,000 days and continue into the second 1,000 days (from 2 to 5 years of age).^18,30 These negative consequences of undernutrition and adversity also reduce growth and developmental outcomes in the next generation.^27,30,31 In addition, children raised in economic hardship are more likely to adopt adverse health-related behaviors (because of limited access to nutritious food and safe physical activity), contributing to the risk of chronic disease.³² Addressing these risk factors early has the potential to stop the progression to chronic disease and disadvantage in adulthood and disrupt this vicious intergenerational cycle.

A ROLE FOR HEALTH PROFESSIONALS AND HEALTHCARE SYSTEMS

The global intergovernmental institutions WHO and UNICEF have set the parameters for improving the health of women and children worldwide, and a body of research has developed the case and means for taking action. Now the onus is on individual governments to turn their population statistics in the right direction. Governments can facilitate change by creating appropriate policies and making funds available, but they will need to work in partnership with health system actors, with the private and nonprofit sectors, and with passionate people who make it all happen.

We have discussed a number of global and national initiatives, but the small or unnoticed projects on our own doorsteps define the success of policies and high-level commitments. Health professionals at all levels of the healthcare system have an important role to play. The example of the HIPPY program (supported by the Australian government) operating within a primary care service demonstrates how a non–health-related program can be integrated successfully in a privately run community health service. Primary care lends itself particularly well to such an integrated and holistic approach as it is rooted in the community and looks after patients’ physical, mental, and social well-being.

The Ochsner-Bonnabel High School public/private partnership in New Orleans, LA supports a school-based health center (SBHC) and illustrates the commitment of health systems to support children and parents living in poverty and disadvantage. Started as part of the state’s 1991 Adolescent School Health Initiative, SBHCs provide comprehensive medical and mental health services and are strategically located in schools with high-risk student populations to address gaps in care. The SBHC at Bonnabel High School provides students with easily accessible healthcare, timely effective medical treatment, and continuity of care for common and chronic conditions such as asthma to reduce school absenteeism. The SBHC emphasizes preventive and proactive care through health screening and risk assessments, including mental illness. It evidently provides needed, equitable care, with roughly 300 general visits and 115 mental health visits per month; 41% of patients are uninsured. The SBHC also promotes healthy lifestyles in collaboration with the student-run Wellness Council. The Bonnabel program’s success, nationally recognized by the Alliance for a Healthier Generation for its efforts to address childhood obesity, attests to the importance of dedicated programs for high-risk populations to turn their health outcomes around.⁴⁸

The SBHC approach has been adopted across the United States and is associated with not only a range of positive health impacts⁴⁹ but also improved school attendance and academic performance.⁵⁰ In some contexts, SBHCs have been used to provide prenatal and antenatal care for adolescents and have been associated with lower rates of low-birth weight infants compared to standard hospital-based care.⁵¹ This outcome exemplifies how existing community health platforms that deliver services to young women can be used to implement interventions targeting the first 1,000 days of life, in addition to addressing the risk factors for chronic disease in older children and young adults. Additionally, the adolescents accessing SBHCs often come from socioeconomic disadvantage and may live in single-parent families and care for younger siblings. Therefore, working to improve their health and education outcomes can have an immediate impact on their own families, as well as their future children.

SHIFTING TO AN INVERSE-CARE LENS

Caring for the young and future generations is the key to tackling the current epidemic of chronic disease. There still is a way to go, especially for LMICs. Although the statistics on the health of women and children in HICs compare favorably to LMICs, there is no place for complacency. The existing healthcare disparities within resource-rich and highly developed countries call for an inverse-care approach.⁵² This concept, launched by Sir Julian Tudor Hart in 1971 is, in 2018, still embarrassingly relevant.