Transmission of alcohol use disorder across three generations: a Swedish National Study

The future of intergenerational transmission research: A prospective, three-generation approach

Dr. Dante Cicchetti's pioneering theory and research on developmental psychopathology have been fundamental to the proliferation of research on intergenerational transmission over the last 40 years. In part due to this foundation, much has been learned about continuities and discontinuities in child maltreatment, attachment, parenting, and psychopathology across generations. Looking towards the future, we propose that this field stands to benefit from a prospective, three-generation approach. Specifically, following established prospective, longitudinal cohorts of children over their transition to parenting the next generation will afford the opportunity to investigate the developmental origins of intergenerational transmission. This approach also can address key outstanding questions and methodological limitations in the extant literature related to the confounding of retrospective and prospective measures; examination of mediators and moderators; and investigation of the roles of biology, environment, and their interplay. After considering these advantages, we offer several considerations and recommendations for future research, many of which are broadly applicable to the study of two or more generations. We hope that this discussion will inspire the leveraging of existing prospective cohorts to carry forward Dr. Cicchetti's remarkable contributions, with the ultimate aim to inform the development of preventions and interventions that disrupt deleterious intergenerational cycles.

Disentangling the multigenerational transmissions of socioeconomic disadvantages and mental health problems by gender and across lineages: Findings from the Stockholm Birth Cohort Multigenerational Study

There is a paucity of research examining the patterning of socioeconomic disadvantages and mental health problems across multiple generations. The current study therefore aimed to investigate the interconnected transmissions of socioeconomic disadvantages and mental health problems from grandparents to grandchildren through the parents, as well as the extent to which these transmissions differ according to lineage (i.e., through matrilineal/patrilineal descent) and grandchild gender. Drawing on the Stockholm Birth Cohort Multigenerational Study, the sample included 21,416 unique lineages by grandchild gender centered around cohort members born in 1953 (parental generation) as well as their children (grandchild generation) and their parents (grandparental generation). Based on local and national register data, socioeconomic disadvantages were operationalized as low income, and mental health problems as psychiatric disorders. A series of path models based on structural equation modelling were applied to estimate the associations between low income and psychiatric disorders across generations and for each lineage-gender combination. We found a multigenerational transmission of low income through the patriline to grandchildren. Psychiatric disorders were transmitted through both the patriline and matriline, but only to grandsons. The patriline-grandson transmission of psychiatric disorder partially operated via low income of the fathers. Furthermore, grandparents' psychiatric disorders influenced their children's and grandchildren's income. We conclude that there is evidence of transmissions of socioeconomic disadvantages and mental health problems across three generations, although these transmissions differ by lineage and grandchild gender. Our findings further highlight that grandparents' mental health problems could cast a long shadow on their children's and grandchildren's socioeconomic outcomes, and that socioeconomic disadvantages in the intermediate generation may play an important role for the multigenerational transmission of mental health problems.

Familial associations in adolescent substance use disorder: a population-based cohort study

BACKGROUND AND AIMS

Family history of substance use disorder (SUD) affects a child's risk of the disorder through both genetic and shared environmental factors. We aimed to estimate the association between parental or older sibling SUD history with the risk of adolescent SUD diagnosis.

DESIGN, SETTING AND PARTICIPANTS

We conducted a population-based cohort study using administrative health-care databases in the Province of Manitoba, Canada, which has a universal and publicly funded health-care system. We included all children born from 1984 to 2000 who have linkages to both parents and were followed until age 18 years. We used generalized estimating equation models to produce unadjusted and adjusted relative risk (RR) estimates of adolescent SUD risk. The study cohort included 134 389 children and 31 307 full sibling pairs; 51.3% were male and 35.4% first-born.

MEASUREMENTS

The exposure was SUD diagnosis in a mother or father in either hospitalization or outpatient physician visit records before the children's age of 13 years. The secondary exposure was an adolescent SUD diagnosis in an older full sibling. The outcome was SUD diagnosis during adolescence (13 and 18 years of age) identified in either hospitalization or physician visit records. Children demographics and characteristics associated with SUD diagnosis were included in the models.

FINDINGS

Of the 134 389 children, 9.5% had a mother with a history of SUD, 11.3% had a father and 1.3% had an older sibling with a history of SUD diagnosis; 2566 (1.9%) had an adolescent SUD diagnosis. An increased risk of adolescent SUD was observed with SUD history in mothers [adjusted RR (aRR) = 2.50; 95% confidence interval (CI) = 2.26, 2.79], fathers (aRR = 2.15; 95% CI = 1.95, 2.37), both parents (aRR = 3.74; 95% CI = 3.24, 4.31) and older sibling (aRR = 3.85; 95% CI = 2.53, 5.87).

CONCLUSIONS

A family history of substance use disorder in parents or older siblings appears to be associated with increased SUD risk in adolescents.

Exploring Factors Associated With Mobile Phone Behaviors and Attitudes Toward Technology Among Adults With Alcohol Use Disorder and Implications for mHealth Interventions: Exploratory Study

BACKGROUND

Alcohol use disorder (AUD) is associated with severe chronic medical conditions and premature mortality. Expanding the reach or access to effective evidence-based treatments to help persons with AUD is a public health objective. Mobile phone or smartphone technology has the potential to increase the dissemination of clinical and behavioral interventions (mobile health interventions) that increase the initiation and maintenance of sobriety among individuals with AUD. Studies about how this group uses their mobile phone and their attitudes toward technology may have meaningful implications for participant engagement with these interventions.

OBJECTIVE

This exploratory study examined the potential relationships among demographic characteristics (race, gender, age, marital status, and income), substance use characteristics (frequency of alcohol and cannabis use), and clinical variables (anxiety and depression symptoms) with indicators of mobile phone use behaviors and attitudes toward technology.

METHODS

A sample of 71 adults with AUD (mean age 42.9, SD 10.9 years) engaged in an alcohol partial hospitalization program completed 4 subscales from the Media Technology Usage and Attitudes assessment: Smartphone Usage measures various mobile phone behaviors and activities, Positive Attitudes and Negative Attitudes measure attitudes toward technology, and the Technological Anxiety/Dependence measure assesses level of anxiety when individuals are separated from their phone and dependence on this device. Participants also provided demographic information and completed the Epidemiologic Studies Depression Scale (CES-D) and the Generalized Anxiety Disorder (GAD-7) scale. Lastly, participants reported their frequency of alcohol use over the past 3 months using the Drug Use Frequency Scale.

RESULTS

Results for the demographic factors showed a significant main effect for age, Smartphone Usage (P=.003; ηp2=0.14), and Positive Attitudes (P=.01; ηp2=0.07). Marital status (P=.03; ηp2=0.13) and income (P=.03; ηp2=0.14) were associated only with the Technological Anxiety and Dependence subscale. Moreover, a significant trend was found for alcohol use and the Technological Anxiety/Dependence subscale (P=.06; R2=0.02). Lastly, CES-D scores (P=.03; R2=0.08) and GAD symptoms (P=.004; R2=0.13) were significant predictors only of the Technological Anxiety/Dependence subscale.

CONCLUSIONS

Findings indicate differences in mobile phone use patterns and attitudes toward technology across demographic, substance use, and clinical measures among patients with AUD. These results may help inform the development of future mHealth interventions among this population.

Exploring the evidence for epigenetic regulation of environmental influences on child health across generations

Environmental exposures, psychosocial stressors and nutrition are all potentially important influences that may impact health outcomes directly or via interactions with the genome or epigenome over generations. While there have been clear successes in large-scale human genetic studies in recent decades, there is still a substantial amount of missing heritability to be elucidated for complex childhood disorders. Mounting evidence, primarily in animals, suggests environmental exposures may generate or perpetuate altered health outcomes across one or more generations. One putative mechanism for these environmental health effects is via altered epigenetic regulation. This review highlights the current epidemiologic literature and supporting animal studies that describe intergenerational and transgenerational health effects of environmental exposures. Both maternal and paternal exposures and transmission patterns are considered, with attention paid to the attendant ethical, legal and social implications.

Sex Differences in the Brain Transcriptome Related to Alcohol Effects and Alcohol Use Disorder

There is compelling evidence that sex and gender have crucial roles in excessive alcohol (ethanol) consumption. Here, we review some of the data from the perspective of brain transcriptional differences between males and females, focusing on rodent animal models. A key emerging transcriptional feature is the role of neuroimmune processes. Microglia are the resident neuroimmune cells in the brain and exhibit substantial functional differences between males and females. Selective breeding for binge ethanol consumption and the impacts of chronic ethanol consumption and withdrawal from chronic ethanol exposure all demonstrate sex-dependent neuroimmune signatures. A focus is on resolving sex-dependent differences in transcriptional responses to ethanol at the neurocircuitry level. Sex-dependent transcriptional differences are found in the extended amygdala and the nucleus accumbens. Telescoping of ethanol consumption is found in some, but not all, studies to be more prevalent in females. Recent transcriptional studies suggest that some sex differences may be due to female-dependent remodeling of the primary cilium. An interesting theme appears to be developing: at least from the animal model perspective, even when males and females are phenotypically similar, they differ significantly at the level of the transcriptome.

Intersection of familial risk and environmental social control on high-risk drinking and alcohol dependence in a US national sample of adults

BACKGROUND

Effects of a family history of alcoholism may be moderated by area-level social control factors. We examine whether increased neighborhood alcohol availability (low social control environment) or increased presence of religious adherents in the county (high social control environment) interact with family history in relation to alcohol outcomes.

METHODS

Weighted data from 12,686 adult drinkers (51% male; mean age 44; 80% White, 9% Black, 11% Hispanic) in three US National Alcohol Surveys were linked with data on area-level off-premise alcohol availability and adherence to religions with strong prohibitions against drinking. Family history density had four levels (family history negative, extended family only, first-degree relative(s) only, high family density). Dichotomous outcomes were past-year high-risk drinking and alcohol dependence. Logistic regression models with interaction terms assessed whether associations of family history with alcohol outcomes differed significantly by area-level social control. Stratified models assessed differences by sex and by race/ethnicity.

RESULTS

In the full sample, effects of first-degree relatives and high family density on high-risk drinking strengthened as alcohol availability increased. This was replicated in the subsample of women and suggested in relation to dependence among men and Black drinkers. For White drinkers, higher religious social control reduced effects of first-degree relatives on high-risk drinking.

CONCLUSIONS

Low social control-in particular, greater density of off-premise alcohol outlets-appears to exacerbate effects of a family history of alcoholism on high-risk drinking. Policy makers should consider differential benefits of decreasing alcohol availability for people from high-risk families to reduce high-risk drinking and alcohol problems.

Mechanisms underlying familial aggregation of exceptional health and survival: A three-generation cohort study

The familial resemblance in length of adult life is very modest. Studies of parent-offspring and twins suggest that exceptional health and survival have a stronger genetic component than lifespan generally. To shed light on the underlying mechanisms, we collected information on Danish long-lived siblings (born 1886-1938) from 659 families, their 5379 offspring (born 1917-1982), and 10,398 grandchildren (born 1950-2010) and matched background population controls through the Danish 1916 Census, the Civil Registration System, the National Patient Register, and the Register of Causes of Death. Comparison with the background, population revealed consistently lower occurrence of almost all disease groups and causes of death in the offspring and the grandchildren. The expected incidence of hospitalization for mental and behavioral disorders was reduced by half in the offspring (hazard ratio 0.53, 95% confidence interval 0.45-0.62) and by one-third in the grandchildren (0.69, 0.61-0.78), while the numbers for tobacco-related cancer were 0.60 (0.51-0.70) and 0.71 (0.48-1.05), respectively. Within-family analyses showed a general, as opposed to specific, lowering of disease risk. Early parenthood and divorce were markedly less frequent in the longevity-enriched families, while economic and educational differences were small to moderate. The longevity-enriched families in this study have a general health advantage spanning three generations. The particularly low occurrence of mental and behavioral disorders and tobacco-related cancers together with indicators of family stability and only modest socioeconomic advantage implicate behavior as a key mechanism underlying familial aggregation of exceptional health and survival.

Family structure and alcohol use disorder: a register-based cohort study among offspring with and without parental alcohol use disorder

AIMS

To assess whether parental alcohol use disorder (AUD) is associated with higher risks of living in a non-intact family and assess whether non-intact family structure is associated with higher risks of AUD in the offspring.

DESIGN

Prospective cohort study.

SETTING

Danish nation-wide registries.

PARTICIPANTS

A total of 9948 parental AUD offspring and 98 136 reference offspring from the Danish population.

MEASUREMENTS

Family structure assessed at birth and at each birthday until age 15 as intact or non-intact (with mother only, father only or neither parent); years lived in an intact family defined as total number of years lived with both parents from birth until the 15th birthday; AUD defined as registration in medical, treatment and cause of death registries. Data were analyzed by Cox regression.

FINDINGS

At birth, 30.9% [95% confidence interval (CI) = 29.1-32.6] of parental AUD offspring and 10.7% (95% CI = 10.3-11.0) of reference offspring lived in a non-intact family. At age 15, the numbers were 84.6% (95% CI = 83.9-85.3) and 38.4% (95% CI = 38.1-38.7). Parental AUD was associated with a higher risk of offspring AUD [hazard ratio (HR) = 1.88, 95% CI = 1.74-2.02]. Offspring were at lower risk of AUD if they lived 15 years in an intact family compared with offspring who never lived in an intact family (HR = 0.67, 95% CI = 0.52-0.87 for those with parental AUD, and HR = 0.53, 95% CI = 0.48-0.59 for those whose parents did not have AUD). Findings were inconclusive as to whether or not an association was present between family structure and AUD among offspring with parental AUD and reference offspring.

CONCLUSIONS

The prevalence of non-intact family structure appears to be higher in offspring of parents with alcohol use disorder (AUD) than among offspring from the general population. Parental AUD appears to be associated with increased risk of offspring AUD, and non-intact family structure appears to be associated with increased risk of offspring AUD regardless of parental AUD.

Alcohol-related mortality following the loss of a child: a register-based follow-up study from Norway

OBJECTIVES

The death of one's child is one of the most stressful events a person can experience. Research has shown that bereaved parents have a higher mortality than non-bereaved parents. This increased mortality might partly be caused directly by long-term stress. However, changes in health behaviour such as an increase in alcohol consumption might also play a role. This study examines the association between losing a child and alcohol-related mortality. In addition to Cox regression models using data covering the entire Norwegian adult population, we employ sibling fixed-effect models in order to partly control for genes and childhood experiences that might be associated with both losing a child and alcohol-related mortality.

DESIGN

A follow-up study between 1986 and 2014 based on Norwegian register data.

SETTING

Norway.

PARTICIPANTS

The entire Norwegian adult population.

PRIMARY OUTCOME MEASURE

Alcohol-related mortality.

RESULTS

An increased alcohol-related mortality was found among parents who had experienced the death of a child. The HR of alcohol-related mortality among those bereaved of a child was 1.59 (95% CI 1.48 to 1.71) compared with non-bereaved parents, for women 2.03 (95% CI 1.78 to 2.32) and for men 1.46 (95% CI 1.34 to 1.59). After including sibling fixed effects, the HR of alcohol-related mortality among parents who had lost a child was 1.30 (95% CI 1.03 to 1.64).

CONCLUSIONS

This study provides evidence of an elevated alcohol-related mortality among parents who have lost a child compared with non-bereaved parents. Although strongly attenuated, there is still an association when adjusting for genetic predisposition for alcohol problems as well as childhood environment using sibling fixed-effect models.

Problematic Facebook use and anxiety concerning use of social media in mothers and their offspring: An actor-partner interdependence model

Previous research has shown significant and positive associations between social anxiety of parents and their adolescent offspring. The main aim of this study was to investigate this relationship in the social media (SM) context. We tested one hundred and fifty-two couples comprising mothers and their adolescent offspring (12-14 years old) on their levels of problematic Facebook use (PFU) and social anxiety concerning SM use. An actor-partner interdependence model highlighted the positive relationship between the PFU scores of mothers and their offspring on the levels of SM social anxiety in the offspring. We discuss the results in the context of intergenerational transfer of problematic technology use and social anxiety.

Intergenerational transmission of alcohol misuse: mediation and interaction by school performance in a Swedish birth cohort

BACKGROUND

Children whose parents misuse alcohol have increased risks of own alcohol misuse in adulthood. Though most attain lower school marks, some still perform well in school, which could be an indicator of resilience with protective potential against negative health outcomes. Accordingly, the aim of this study was to examine the processes of mediation and interaction by school performance regarding the intergenerational transmission of alcohol misuse.

METHODS

Data were drawn from a prospective Swedish cohort study of children born in 1953 (n=14 608). Associations between parental alcohol misuse (ages 0-19) and participants' own alcohol misuse in adulthood (ages 20-63) were examined by means of Cox regression analysis. Four-way decomposition was used to explore mediation and interaction by school performance in grade 6 (age 13), grade 9 (age 16) and grade 12 (age 19).

RESULTS

Mediation and/or interaction by school performance accounted for a substantial proportion of the association between parental alcohol misuse and own alcohol misuse in adulthood (58% for performance in grade 6, 27% for grade 9 and 30% for grade 12). Moreover, interaction effects appeared to be more important for the outcome than mediation.

CONCLUSION

Above-average school performance among children whose parents misused alcohol seems to reflect processes of resilience with the potential to break the intergenerational transmission of alcohol misuse. Four-way decomposition offers a viable approach to disentangle processes of interaction from mediation, representing a promising avenue for future longitudinal research.

Socioeconomic status and alcohol use disorders across the lifespan: A co-relative control study

Objectives

Alcohol use disorders (AUD) is well known to aggregate in families and is associated with socioeconomic status (SES). The objective was to study the effect of education, income and neighborhood SES in adulthood on AUD, and to explore whether the potential associations were confounded by shared familial factors, by using a co-relative control design.

Methods

Data on AUD was drawn from the Swedish inpatient and outpatient care registers; prescription drug register; and crime data. Through national population registers we collected information on income, education and neighborhood SES at age 25, 30, 35 and 40 years in all individuals born in Sweden between 1950 and 1980. Each sex-specific stratum consisted of approximately 750,000–1,200,000 individuals, who were followed for AUD for a mean follow-up time ranging between 10 and 15 years until the end of 2013. Cox proportional hazards models were used to investigate the risk of AUD as a function of income, education and neighborhood SES in the general population and in pairs of first cousins and full siblings within the same sex, who differed in their exposure to the SES measure.

Results

Higher educational level, higher income and higher neighborhood SES were all associated with a reduced risk for AUD for both males and females in all ages. The potentially protective effect remained but was attenuated when comparing pairs of first cousins and full siblings.

Conclusions

High educational level and income in adulthood, as well as high neighborhood socioeconomic status, may represent protective factors against alcohol use disorders, even when shared familial factors, e.g. childhood socioeconomic status and genetic factors, have been taken into account.

Familial transmission of externalizing syndromes in extended Swedish families

Risk for criminal behavior (CB), alcohol use disorder (AUD), and drug abuse (DA) are known to be familial. We know less about their transmission across three generations. We examined 844,109 probands born in Sweden 1980-1990, their parents, aunts/uncles, and grandparents for registration in population-based registers for CB, AUD, and DA. Mean tetrachoric relative-proband correlations (95% CIs) were highest for DA (+0.24, 0.24-0.25), followed by CB (+0.23,0.22-0.23) and AUD (+0.17, 0.16-0.17). AUD and CB were relatively stably transmitted across generations, while DA resemblance among relatives was stronger in the younger generations. For all three syndromes, male-male transmission was modestly stronger than female-female. Cross-sex transmission was significantly weaker than same-sex transmission for DA and CB but not AUD. Risk to probands with only an affected grandparent or aunt/uncle were increased 50-60% for CB and AUD, and 70-100% for DA. Parallel figures for affected parents only and parents + grandparent or aunt/uncle were 2-3-fold and 4-5-fold for CB and AUD, and 4-5-fold and 6-7-fold for DA. CB, AUD, and DA are all substantially familial in the Swedish population with the transmission across three generations stable for CB and AUD but not DA. Modest quantitative sex effects are seen in the familial transmission of CB, AUD, and DA, and qualitative sex effects for CB and DA. Risk prediction in offspring is orderly with affection status in grandparental and avuncular relationships adding appreciably to that from the parental generation.