TY - JOUR
T1 - Peer Social Genetic Effects and the Etiology of Substance Use Disorders, Major Depression, and Anxiety Disorder in a Swedish National Sample
AU - Salvatore, Jessica E.
AU - Ohlsson, Henrik
AU - Sundquist, Jan
AU - Sundquist, Kristina
AU - Kendler, Kenneth S.
PY - 2024/9/1
Y1 - 2024/9/1
N2 - OBJECTIVE: There is growing interest in how peers' genotypes may influence health (i.e., peer social genetic effects). The authors sought to clarify the nature of peer social genetic effects on risk for drug use disorder, alcohol use disorder (AUD), major depression, and anxiety disorder. METHOD: Cox models were used with data from a population-based Swedish cohort (N=655,327). Outcomes were drug use disorder, AUD, major depression, and anxiety disorder registrations between ages 17 and 30 from medical, criminal, and pharmacy registries. The authors indexed peer social genetic effects with peers' family genetic risk scores (FGRSs) for the same disorders, which are personalized measures of genetic risk inferred from diagnoses in first- to fifth-degree relatives. RESULTS: Across disorders, peer FGRSs predicted increased risks of proband registration (hazard ratio range, 1.01-1.59), with stronger effects for drug use disorder and AUD than for major depression and anxiety disorder. Peer social genetic effects were stronger for school classmates than for geographically proximal peers, and for peers from upper secondary school (ages 16-19) versus peers from lower secondary school (ages 7-16). Peer social genetic effects remained significant following statistical control for sociodemographic confounders, whether peers were affected, and peers' FGRS for educational attainment. Peer social genetic effects were more pronounced for probands at higher genetic risk. CONCLUSIONS: The genetic makeup of adolescents' peers has long-reaching consequences on risks for drug use disorder, AUD, major depression, and anxiety disorder. Individuals at high genetic risk are more sensitive to social genetic effects. Alternative hypotheses such as sociodemographic stratification, exposure to affected peers, and genetic predispositions for educational attainment did not explain the risk associated with peer social genetic effects for substance use and psychiatric disorders.
AB - OBJECTIVE: There is growing interest in how peers' genotypes may influence health (i.e., peer social genetic effects). The authors sought to clarify the nature of peer social genetic effects on risk for drug use disorder, alcohol use disorder (AUD), major depression, and anxiety disorder. METHOD: Cox models were used with data from a population-based Swedish cohort (N=655,327). Outcomes were drug use disorder, AUD, major depression, and anxiety disorder registrations between ages 17 and 30 from medical, criminal, and pharmacy registries. The authors indexed peer social genetic effects with peers' family genetic risk scores (FGRSs) for the same disorders, which are personalized measures of genetic risk inferred from diagnoses in first- to fifth-degree relatives. RESULTS: Across disorders, peer FGRSs predicted increased risks of proband registration (hazard ratio range, 1.01-1.59), with stronger effects for drug use disorder and AUD than for major depression and anxiety disorder. Peer social genetic effects were stronger for school classmates than for geographically proximal peers, and for peers from upper secondary school (ages 16-19) versus peers from lower secondary school (ages 7-16). Peer social genetic effects remained significant following statistical control for sociodemographic confounders, whether peers were affected, and peers' FGRS for educational attainment. Peer social genetic effects were more pronounced for probands at higher genetic risk. CONCLUSIONS: The genetic makeup of adolescents' peers has long-reaching consequences on risks for drug use disorder, AUD, major depression, and anxiety disorder. Individuals at high genetic risk are more sensitive to social genetic effects. Alternative hypotheses such as sociodemographic stratification, exposure to affected peers, and genetic predispositions for educational attainment did not explain the risk associated with peer social genetic effects for substance use and psychiatric disorders.
KW - Adolescence
KW - Anxiety Disorder
KW - Family Genetic Risk Score
KW - Major Depression
KW - Peer Social Genetic Effects
KW - Substance-Related and Addictive Disorders
UR - http://www.scopus.com/inward/record.url?scp=85202984781&partnerID=8YFLogxK
U2 - 10.1176/appi.ajp.20230358
DO - 10.1176/appi.ajp.20230358
M3 - Article
C2 - 39108160
AN - SCOPUS:85202984781
SN - 0002-953X
VL - 181
SP - 824
EP - 833
JO - American Journal of Psychiatry
JF - American Journal of Psychiatry
IS - 9
ER -