Developmental Origins of Health and Disease Flashcards
can the rapid increases in rates of non-communicable diseases be explained by genetics
no
non-communicable diseases in developed countries are increasing rapidly which is not in correlation to ____ that is not changing much
changes in genetic makeup of the population
what was the relationship found between average income and CHD (coronary heart disease)
high income had lower rates of CHD
what was the relationship between REGIONAL infant mortality rates and heart disease 50yrs later & why
- strong correlation
- ie/ babies who were undernourished before or after birth were more likely to have poor health much later
- high infant mortality rate reflects poor maternal health and nutrition -> suggest adverse pregnancy and infant conditions that impact later health (IN REGIONAL)
what factor strongly predicted whether someone died of CVD before reached 65 years of age
birth weight
what does the hook like pattern (non-linear) of birth weight to CVD related death <65yo indicate
- increasing risk of CVD with decreasing birth weight
- but also increasing risk of CVD at the highest birthweight groups
what does gestational diabetes do to foetus
- can cause foetal overgrowth
- increases risk of later disease
relationship between birth weight and current health (alive)
- low birth weight had higher rates non-communicable disease
what is the Barker hypothesis
- adverse nutrition in early life, including prenatally - as measured by low birth weight -> increases susceptibility to cardiometabolic diseases
what has the Barker hypothesis evolved into
DOHaD paradigm
what was Barker’s suggestion (which is supported by many studies) & what was the suggestion that opposed it
- that adult disease was affected by events before birth
- adult disease attributed to genetics and adult lifestyle
list some cardiovascular and metabolic diseases that are increased risk later in life from lower birth weight
- diabetes, insulin resistance, insulin deficiency
- hypertension
- CVD
- stroke
list some neurological and mental diseases that are increased risk later in life from lower birth weight
- schizophrenia
- impaired neuromotor function
- poor cognition
list some other diseases (repro, bone, respiratory, immune) that are increased risk later in life from lower birth weight
- polycystic ovary syndrome
- osteoporosis
- chronic obstructive lung disease
- asthma (overall, mostly not allergic)
- early life susceptible to infection
list some diseases that are increased risk later in life from very high birth weight
- some cancers (breast, ovarian, prostate cancers)
- allergy (eczema /allergic dermatitis, food allergy)
a change from nutrient-poor to nutrient-rich environments were associated with increase or decrease in disease risk
this is referred to as the ______ _______ hypothesis
- increase risk
- thrifty phenotype hypothesis
(Hales and Barker) proposed what as the thrifty phenotype hypothesis
(concerns foetal nutrition)
- low availability of nutrients prenatally
- followed by improvement in nutritional availability in early childhood
- caused increased risk metabolic disorders
- due to permanent changes in metabolic processing of glucose-insulin determined in utero
explain the ‘set points’ of hales & barker thrifty phenotype hypothesis
(concerns foetal nutrition)
- undernourished foetus has set points -> saves energy possible
- if more nutrients are available after birth, a thrifty response results in obesity and metabolic poor health
what is low birth weight a marker of for research purposes
- foetal nutrition
what is Foetal Origins of Adult Disease (FOAD) hypothesis
- that low birth weight (a marker of foetal nutrition) not the only exposure that affects later health (broadening of thrifty phenotype hypothesis)
- the environment a foetus is exposed to affects foetal development, which in turn alters the individual’s risks of later disease
what is the refinement of the thrifty phenotype
- ‘predictive adaptation’
- not by barker
what is the concept of predictive adaptation
- foetuses adapt to environment they expect to enter into once outside womb -> increase likelihood of survival (short-term benefit)
- results in adverse consequences for long-term health when prenatal and postnatal environments don’t align
- adult disease risk was increased by this ‘developmental mismatch’
developmental origins of health and disease paradigm (DOHaD) reflects what & not what about disease risk
- disease risk reflects cumulative effect of events across a person’s lifespan that changes an individual’s health trajectory
- disease risk does not reflect a once-off exposure
according to the developmental origins of health and disease paradigm (DOHaD), individual’s health trajectory have greatest effect from events when
- events that occur early on have greatest effects on health trajectories
according to the developmental origins of health and disease paradigm (DOHaD), does early or late intervention provide greater potential benefit for life-long health
- earlier intervention
define DOHaD
- a disturbance of the environment in early life, occurring at critical stages of the development of regulatory systems and their target tissues, that alters functional developmental and capacity, therefore predisposing to impaired function and disease in alter life
(3) main types of early life exposures that program later health and disease risk
- maternal
- paternal
- placental
examples of maternal factors of exposure
- diseases like diabetes
- smoking during pregnancy
- maternal stress
how do maternal factors of exposure affect foetus
- affect foetal nutrition
- result in foetal exposure to chemicals that cross placenta
examples of paternal factors that of exposure
- obesity and poor diet quality which affect sperm
what is one of the most common reasons for poor foetal growth in developed countries?
- poor placental function
function of the placenta
- transport nutrients from mother to foetus, including: oxygen, glucose, amino acids, methyl donors
by what process / mode are nutrients (including most amino acids) transported across placenta against conc gradient
- active process
how is foetal exposure to active corticosteroids (cortisol in humans) reduced
- deactivates maternal stress hormones as they pass across placenta
list 2 roles of placenta
- actively metabolises many nutrients
- important source of hormones that regulate maternal adaptation to pregnancy
what is excess foetal corticosteroid exposure a well-established risk factor of
- poor progeny (foetus) health