Parental Preconception Adversity and Offspring Health in African Americans: A Systematic Review of Intergenerational Studies

Background: This systematic review explores the empirical literature addressing the association between parental preconception adversity and offspring physical health in African-American families. Method: We conducted a literature search in PubMed, Web of Science, PsycINFO, CINAHL, and Scopus through June 2021. Articles were included if they: reported data about at least two generations of African-American participants from the same family; measured parental preconception adversity at the individual level; measured at least one offspring physical health outcome; and examined associations between parental adversity and child health. Results: We identified 701 unique articles; thirty-eight articles representing 30 independent studies met inclusion criteria. Twenty-five studies (83%) reported that parental preconception adversity was associated with child health; six studies (20%) reported that parental preconception adversity was not associated with at least one offspring outcome; several studies reported both. Only six studies (20%) reported an association specific to African Americans. Conclusion: Empirical evidence linking parental preconception adversity with offspring physical health in African Americans is limited and mixed. In the current literature, very few studies report evidence addressing intergenerational associations between parental preconception adversity and offspring physical health in the African-American population, specifically, and even fewer investigate forms of parental preconception adversity that have been shown to disproportionately affect African Americans (e.g., racism). To better understand root causes of racial health disparities, more rigorous systematic research is needed to address how intergenerational transmission of historical and ongoing race-based trauma may impact offspring health among African Americans.

Representativeness of the exposed cohort Enter 0 or 1: 1 = truly representative of the average _____ in the community 1 = somewhat representative of the average _____ in the community 0 = selected group of users (e.g., nurses, volunteers) 0 = no description of the derivation of the cohort Selection of the non-exposed cohort Enter 0 or 1: 1 = drawn from the same community as the exposed cohort 0 = drawn from a different source 0 = no description of the derivation of the non-exposed cohort *Ascertainment of exposure Enter 0 or 1: 1 = biological test (e.g., blood/urine) 1 = structured interview 1 = written self-report that characterizes dose (current or cumulative) 0 = written self-report without quantification of exposure 0 = no description *Ascertainment of exposure done prospectively or retrospectively Enter 0 or 1: 1 = Prospectively 0 = Retrospectively Demonstration that outcome of interest was not present at start of study, OR baseline assessment Enter 0 or 1: 1= yes 0 = no Comparability (2 maximum total points):

Comparability of cohorts on the basis of the design or analysis
Add points: Minimum 0, Maximum 2 1 = study accounts/controls for ______ (most important factor) 1 = study controls for any additional factor 0 = no adjustment for potential confounders Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) Ascertainment of exposure Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) Ascertainment of exposure Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort Ascertainment of exposure Representativeness of the exposed cohort 0select group of pregnant women (convenience sampling) 0select group of pregnant women (convenience sampling) 1truly representative of the average child born in the U.S. (probability sampling) 1truly representative of the average child born in the U.S. (probability sampling) 1truly representative of the average child born in the U.S. (probability sampling) Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) Ascertainment of exposure 1written self-report that characterizes dose (modified validated self-report measure [ETI-SF]) 1written self-report that characterizes dose (selfreport of binary measure) Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) 1drawn from the same community as the exposed cohort (same sample) Ascertainment of exposure  Miller et al. (2017) Representativeness of the exposed cohort 0select group of pregnant women (convenience sampling) Selection of the nonexposed cohort 1drawn from the same community as the exposed cohort (same sample) Ascertainment of exposure 1written self-report that characterizes dose Ascertainment of exposure done prospectively or retrospectively 0retrospectively Demonstration that outcome of interest was not present at start of study, OR baseline assessment 1yes Comparability of cohorts on the basis of the design or analysis 1study controls for any additional factors (e.g., maternal demographics, education, and obstetrical confounders [e.g., nulliparity]) Assessment of outcome 1 -objective measure (maternal and neonatal charts) Was follow-up long enough for outcomes to occur?

1yes (offspring was born)
Adequacy of followup of prospective cohorts/Adequacy of response of retrospective cohorts 1subjects lost to follow-up unlikely to introduce bias (< 30% lost)

Risk of Bias (ROB):
Moderate ROB; the primary source of bias was the nonrepresentative sample used; a retrospective measure of maternal preconception adversity was also used Supplemental Appendix H. Newcastle Ottawa Scale for Quality Assessment for Cross-Sectional Studies Criteria Selection (5 maximum total points):

Representativeness of the sample
Enter 0 or 1: 1 = truly representative of the average in the target population (all subjects or random sampling) 1 = somewhat representative of the average in the target population (non-random sampling) 0 = select group of users (e.g., nurses, volunteers) 0 = no description of the sampling strategy

Non-respondents
Enter 0 or 1: 1 = comparability between respondents and non-respondents characteristics is established and the response rate is satisfactory 0 = the response rate is unsatisfactory, or the comparability between respondents and non-respondents is unsatisfactory 0 = no description of the response rate or the characteristics of the respondents and non-respondents

Sample size
Enter 0 or 1: 1 = justified and satisfactory 0 = not justified

Ascertainment of exposure
Enter 0 or 1: 1 = validated measurement tool 1 = non-validated measurement tool that is available or described 0 = no description of the measurement tool *Ascertainment of exposure done prospectively or retrospectively Enter 0 or 1: 1 = Prospectively 0 = Retrospectively

Comparability (2 maximum total points):
The subjects in different outcome groups are comparable, based on the study design or analysis -confounding factors are controlled Add points: Minimum 0, Maximum 2 1 = study accounts/controls for the most important factor (select one) 1 = study controls for any additional factor 0 = no adjustment for potential confounders Outcome (3 maximum total points):

Statistical test
Enter 0 or 1: 1 = the statistical test used to analyze the data is clearly described and appropriate, and the measurement of the association is presented, including confidence intervals and the probability level (p value) 0 = the statistical test is not appropriate, not descried or incomplete Risk of Bias (ROB): High ROB; the primary sources of bias were the small and nonrepresentative sample used, and lack of information about participants' response rate; a retrospective measure of maternal preconception adversity was also used High ROB; the primary sources of bias were the small and nonrepresentative sample used, and lack of information about participants' response rate; a retrospective measure of maternal preconception adversity was also used Moderate ROB; the primary source of bias was the nonrepresentative sample used; a retrospective measure of maternal preconception adversity was also used High ROB; the primary sources of bias were the non-representative sample used and the lack of information about participants' response rate; a retrospective measure of maternal preconception adversity and maternal report of offspring health were also used Low ROB; the primary source of bias was the retrospective measure of maternal preconception adversity; maternal report of offspring health was also used CRITERIA CATEGORIES Lê-Scherban et al. (2018) Representativeness of the exposed cohort 1 -somewhat representative of the average resident of Philadelphia & its surrounding counties (stratified sampling) Non-respondents 0the response rate is unsatisfactory (67%) 1) Is the case definition adequate? Representativeness of the exposed cohort a) yes, with independent validation* b) yes, e.g., record linkage or based on self-reports c) no description 2) Representativeness of the cases a) consecutive or obviously representative series of cases* b) potential for selection biases or not stated 1) Comparability of cases and controls on the basis of the design or analysis a) study controls for _______________ (Select the most important factor.)* b) study controls for any additional factor* (These criteria could be modified to indicate specific control for a second important factor.)

Exposure (A study can be awarded a maximum of one star for each numbered item):
1) Ascertainment of exposure a) secure record (e.g., surgical records)* b) structured interview where blind to case/control status* c) interview not blinded to case/control status d) written self-report or medical record only e) no description 2) Same method of ascertainment for cases and controls a) yes* b) no 3) Non-Response rate a) same rate for both groups* b) non respondents described c) rate different and no designation Supplemental Appendix K. Newcastle Ottawa Scale for Quality Assessment for Case-Control Studies

CRITERIA CATEGORIES
Freedman et al. (2017) Is the case definition adequate? 1yes, with independent validation (medical records) Representativeness of the cases 1consecutive or obviously representative series (population-based study with stratified random sampling) Selection of controls 1community controls (same birth hospitals as cases) Definition of controls 1index delivery did not result in stillbirth Comparability of cases and controls on the basis of the design or analysis 1study controls for any additional factors (e.g., maternal education, age, time between index delivery & follow-up interview) Ascertainment of exposure 0written self-report (CTQ) Same method of ascertainment for cases and controls 1yes (CTQ) Non-response rate 0rate different for each group (17% non-response for cases vs. 25% non-response for controls) Risk of bias (ROB): Moderate ROB; the primary source of bias was the different participant response rates in the case and control groups; a retrospective measure of maternal preconception adversity was also used