Lifecourse Epi Lecture 7 Flashcards
Adenocarcinoma in Young Women
Adenocarcinoma of the vagina is rare, usually occurs in women over 50 years old
1966-1969: eight cases of young women (aged 15-22 years) seen at two hospitals in Boston
Diagnoses were delayed
High prevalence of benign adenosis of the vagina in all cases
Clustering of cases warranted focus on similarities between them
Methods for Adenocarcinoma Case Study
Retrospective case-control study to compare cases and their families in detail
Each case matched with 4 controls, born within five days and on same type of hospital service
Key Findings in Adenocarcinoma Case Study
mothers took estrogen while pregnant
All mothers began treatment during first trimester
Prior pregnancy loss and bleeding during pregnancy more common among cases
DES alone doesn’t cause disease
1 in 8 mothers didn’t take DES during pregnancy
Adenocarcinomas occurred in older women before DES
4 in 8 mothers used DES during other pregnancies, without adverse effect in children
Risk of tumor development in children exposed to DES appears to be small
Importance of Adenocarcinoma Case Study
“Biological time bomb”
First example of transplacental carcinogenesis in humans
Illustrates a specific biological vulnerability
Clear demonstration of effects of prenatal exposure on health outcomes later in life
Peaks in risk at multiple times during lifecourse
Timing of cases (1946-1951) coincided with widespread use of estrogens to treat high-risk pregnancies
Possibility of future cases in children and grandchildren of women treated during pregnancy
Need for more frequent cervical screenings for women exposed to DES in utero
2-4 million women exposed to DES during pregnancy in 1970s
Risk and Protective Factors for Early Childhood Development
Exposure to biological and psychosocial risks affects the developing brain and may compromise the development of children
Impact of inequalities in child development begin prenatally, continue through early years of life
With cumulative exposure to developmental risks, disparities may widen and trajectories become more firmly established
Reducing inequalities requires early integrated interventions and should target the risks to which children in a particular setting are exposed
Perhaps, most effective and cost-efficient time to prevent inequalities is early in life, before trajectories have been firmly established
Action, or lack of action, have lifetime consequences for adult functioning, for the care of the next generation and for the wellbeing of societies
How Risk Factors and Stress Affect Brain and Behavioral Development
3 Translational Processes
Extent and nature of deficits depend on timing
Co-occurring and cumulative influences
Differential activity
Maternal Nutrition
Among pregnant women in low and middle-income countries…
42% are anemic
60% are iron deficient
But, little information on perinatal iron deficiency and child development
Significant evidence that the fetus is resilient to dietary and other environmental insults
Infant and child nutrition
16% of births in low and middle-income countries are low birth weight
As high as 27% in south Asia
Most LBW births are attributed to intrauterine growth restriction (IUGR)
39% of infants in these countries are exclusively breastfed
Variation in duration of breastfeeding across cultures
Long-term effects?
Forces of Continuity and Change: Internal Dispositions
Formative nature of the first years of life
Attachment theory
Children develop internal working models of their relationships with primary caregivers
These models serve as foundation for later interpersonal relationships
Experimental basis for child’s perceptions of caregivers’ accessibility and responsiveness, and their own deservingness of care
Internal Disposition: Temperament
Defined as… Constitutional (biologically based) differences in reactivity and self-regulation OR Basic stable personality characteristics OR Behavioral style
Relationship with the nature and quality of interpersonal interactions
Children Who Enjoy Success as Adults…
Evidence from a cohort of children from disadvantaged backgrounds
More active, cuddly and good-natured at age 1
Correlated with later childhood autonomy, good peer relations, and an internal locus of control
Lifecourse Continuities
Attributed to internalized societal norms, knowledge, behavioral tendencies, attitudes and values
Cognitive, emotional and social skills are developed through interaction with families, schools and peers
Socialization
Possible explanation for intergenerational continuities in behavior and attainment
Example: working class parents who place high value on conformity to external authority Compared with middle class parents who emphasize children’s self-direction Class differences in parental values may perpetuate inequality across generations by preparing children to occupy similar class positions in adulthood
Stability of Environments
Continuity in social and interpersonal environments sustained by…
Macro-level processes of stratification that impede major changes in location within social hierarchies
Micro-level processes of environmental selection – support and reinforce pre-existing psychological and behavioral tendencies
Macro- and micro-level processes that encourage environmental stability create continuity over the lifecourse
Reflects the motivated selection and creation of environments by individuals
“The self” emphasized as a motivational system in the selection of social and interpersonal environments
Motivated to…
Maintain and enhance positive self-conceptions
Maintain consistency in the self
Seek social relations that are consistent with their self-conceptions
Those with negative self-views set low goals and self-handicap
Cumulative Nature of Development
Promotes lifecourse continuities
Early biological insults may limit future neurological and physiological potential
i.e. prenatal alcohol exposure, poor maternal nutrition
Specific stages during which children must develop cognitive and emotional capacities, or they will lose the ability to achieve full developmental potential
Transitions, Turning Points and Human Agency
Stability in lifecourse punctuated by physiological alterations, life transitions and turning points that alter developmental and experiential trajectories
Hormonal changes associated with puberty, creation of new physical and social selves that require adjustment and adaptation
Turning Points
Period or points in time “in which a person has undergone a major transformation in views about the self, commitments to important relationships or involvement in significant life roles”
Family formation, unemployment, self-realizations, reinterpretations of past events, etc.
Empirical Discontinuity between Childhood and Adulthood
Multiple pathways to specific outcomes
Specific childhood experiences (i.e. parental divorce) may be linked to multiple adult outcomes
Most theories of lifecourse continuities are insufficiently specific to predict which adult outcomes should be predicted by which childhood experiences, and vice versa
Childhood Antecedents of Adult Disease
Low birth weight, placenta size, weight gain in 1st year of life may increase risk for chronic diseases in adulthood
Heart disease, diabetes, obstructive lung disease, schizophrenia
Specific childhood diseases also increase the risk of cause-specific adult mortality
e.g. childhood respiratory tract infections adult chronic obstructive lung disease
Debate about the primacy of physiological processes
One side: adult diseases are “programmed’ by biological processes during prenatal period and infancy
Other side: infant developmental indicators serve as markers for generally poor living conditions during childhood that have effects on later health
Low SES during childhood is related to risk factors for and the prevalence of adult disease
Complicated by complex, interlocking nature of trajectories of health and SES
Ben-Shlomo & Smith: Deprivation in infancy or adult life, and mortality risk
Mortality rates for various diseases are positively correlated with infant mortality rates taken around the time when the people dying would have been born.
Ischemic heart disease, stroke, bronchitis, stomach cancer, overall cancer, cervical cancer, and lung cancer
Also related to low present-day SES position, as shown by social class or by a deprivation index
McLeod: Connections Between Childhood and Adulthood
“The plausibility of these diverse pathways suggests that the full relevance of childhood socioeconomic circumstances for adult health can only be determined through a complete accounting of life course trajectories” (McLeod, 2003)
Childhood Adversity and Adult Life
Adverse childhood events constrain future life options, but also create opportunities for development
Children who…
lose parents
are separated from parents
whose parents divorce
More likely to experience adverse effects of childhood adversity
Adult Outcomes of Childhood Parental LossThrough Divorce, Death or Out-of-Home Placement
Primary outcomes…
Psychological well-being
Marital outcomes
Socioeconomic attainment
Childhood Parental Divorce
Modest, but significant, association with psychological well-being in adulthood
Psychological effects persist and possibly strengthen through adult life course
Effects of family conflict comparable to effects of divorce
Childhood adversities cluster within families
Children from divorced homes also fare less well economically than children from stable, two-parent homes
Attain lower levels of education and are employed in lower status occupations as adults
“as these young men and women faced the developmental tasks of establishing love and intimacy, they most felt the lack of a template for a loving, enduring and moral relationship between men and women” (McLeod, 2003)
