Poor growth prior to early childhood: Decreased health and life‐span in the adult

Abstract

Previous studies in animal populations have shown that stunted neural and thymolymphatic growth early in development may result in permanently impaired neural and immune function, decreased body growth, vertebral wedging, and decreased life-span. In the human adult, small vertebral neural canal (VNC) diameters may reflect early stunted neural and immune development and impaired function that leads to decreased health (inferred by greater vertebral wedging) and life-span in the adult. VNC, which complete their growth by early childhood (age 4), are markers of early development in adults. On the other hand, features following general body growth, such as height, weight (represented here by vertebral body height) continues to grow until young adulthood. They are less reliable, because they readily experience catch-up growth (even in chronically stressed populations) and, unlike VNC, may mask poor early growth. To test associations between early growth and adult health and life-span in humans, we measured 2,060 VNC, vertebral heights, vertebral wedging, nerve-root tunnel lengths, severity of vertebral osteophytosis, and ages at death in 90 adult (aged 15-55 years) prehistoric skeletons (950-1300 A.D.). Tibial lengths were also measured in a subsample (n = 30). Multivariate, bivariate, and nonparametric analyses showed that small VNC are significantly associated with greater vertebral wedging and decreased life-span (P less than 0.05-0.00001). VNC are independent of vertebral body heights and tibial lengths (general body growth). VNC, but not statural components, are useful in predicting adult health, presumably because they reflect neural and immune development and do not readily experience catch-up growth. Thus, longitudinal retrospective measures of early growth and adult health were systematically linked within individuals regardless of confounding factors operating over the 350-year time period. Since this research was completed, this model has repeatedly been independently confirmed in four living urban industrial populations. Longitudinal retrospective analysis was employed together with direct measures of VNC, neural and immune function. Together these results suggested that it may be essential to improve growth prior to early childhood in order to maximize adult health and life-span.

The use of non‐adult vertebral dimensions as indicators of growth disruption and non‐specific health stress in skeletal populations

“…However, Gilsanz et al (1994, 1997) found that while the cross‐sectional area of the vertebral bodies was larger in boys than girls, measurements of vertebral body height were comparable at all ages (Gilsanz et al, 1994, 1997). Limited sexual dimorphism in the TR diameters of adult males and females has also been reported and this is an important advantage of studies of vertebral growth (Clark et al, 1986; Watts, 2011). However, advancement in the ability to assess pubertal development provides an additional avenue through which vertebral growth can be assessed in the future (Shapland and Lewis, 2013).…”

“…The formation of the anteroposterior (AP) and transverse diameters (TR) of the neural canal is predominantly complete in early childhood, reaching ∼95% of its final size by 5 years of age (Diméglio, 1993). Consequently, evidence of growth disturbance during early postnatal life may become “locked into” these dimensions (Clark et al, 1986; Clark, 1988; Diméglio, 1993; Larsen, 1997; Watts, 2011, 2013a,b). The value of the AP and TR dimensions of the vertebrae has been previously recognized and implemented in both adult (Clark et al, 1986; Clark, 1988; Watts, 2011, 2013a,b) and non‐adult (Watts, 2013b) skeletal collections.…”

“…Consequently, evidence of growth disturbance during early postnatal life may become “locked into” these dimensions (Clark et al, 1986; Clark, 1988; Diméglio, 1993; Larsen, 1997; Watts, 2011, 2013a,b). The value of the AP and TR dimensions of the vertebrae has been previously recognized and implemented in both adult (Clark et al, 1986; Clark, 1988; Watts, 2011, 2013a,b) and non‐adult (Watts, 2013b) skeletal collections. However, these measurements, as well as that of vertebral body height, have yet to be explored as a potential method to map the growth of non‐adults.…”

Dental indicators of stress and reduced age at death in prehistoric Native Americans

“…Vertebral neural canal size has the same growth curve as the thymolymphatic tissues. Small vertebral neural canal size may reflect a systemic perturbation occurring during prenatal or early postnatal development, resulting in damage to developing neural and thymolymphatic tissues, with consequent effects on neural and immune system function (Clark et al, 1986). It is also possible that environmental stressors may biologically damage the immune system of the developing fetus or child through a mechanism other than the specific endocrine pathways of the stress response.…”

Do environmental disturbances of an individual's growth and development influence the later bone involution processes? A study of two mediaeval populations

“…Among many skeletal indications of living conditions, one may distinguish the ones that reflect the occurrence of disturbances in early stages of ontogenesis, when the development is most rapid, that is, in the foetal period and early childhood (Clark et al, 1986). If these disturbances are severe, frequent and longlasting, they lead to considerable retardation of growth.…”