Effects of Recent Stress and Variation in the Serotonin Transporter Polymorphism (5-HTTLPR) on Depressive Symptoms: A Repeated-Measures Study of Adults Age 50 and Older.

TitleEffects of Recent Stress and Variation in the Serotonin Transporter Polymorphism (5-HTTLPR) on Depressive Symptoms: A Repeated-Measures Study of Adults Age 50 and Older.
Publication TypeJournal Article
Year of Publication2016
AuthorsArpawong, TE, Lee, J, Phillips, DF, Crimmins, EM, Levine, ME, Prescott, CA
JournalBehavior Genetics
Volume46
Issue1
Pagination72-88
ISSN Number1573-3297
KeywordsAged, Alleles, depression, Depressive Disorder, Ethnic Groups, Female, Gene-Environment Interaction, Genetic Association Studies, Genetic Predisposition to Disease, Haplotypes, Humans, Life Change Events, Male, Middle Aged, Polymorphism, Single Nucleotide, Promoter Regions, Genetic, Serotonin Plasma Membrane Transport Proteins, Stress, Psychological
Abstract

Depending on genetic sensitivity to it, stress may affect depressive symptomatology differentially. Applying the stress-diathesis hypothesis to older adults, we postulate: (1) recent stress will associate with increased depressive symptom levels and (2) this effect will be greater for individuals with at least one short allele of the serotonin transporter gene promoter region (5-HTTLPR). Further, we employ a design that addresses specific limitations of many prior studies that have examined the 5-HTTLPR × SLE relation, by: (a) using a within-person repeated-measures design to address fluctuations that occur within individuals over time, increase power for detecting G × E, and address GE correlation; (b) studying reports of exogenous stressful events (those unlikely to be caused by depression) to help rule out reverse causation and negativity bias, and in order to assess stressors that are more etiologically relevant to depressive symptomatology in older adults. The sample is drawn from the Health and Retirement Study, a U.S. population-based study of older individuals (N = 28,248; mean age = 67.5; 57.3 % female; 80.7 % Non-Hispanic White, 14.9 % Hispanic/Latino, 4.5 % African American; genetic subsample = 12,332), from whom measures of depressive symptoms and exogenous stressors were collected biannually (1994-2010). Variation in the 5-HTTLPR was characterized via haplotype, using two single nucleotide polymorphisms (SNPs). Ordered logit models were constructed to predict levels of depressive symptoms from 5-HTTLPR and stressors, comparing results of the most commonly applied statistical approaches (i.e., comparing allelic and genotypic models, and continuous and categorical predictors) used in the literature. All models were stratified by race/ethnicity. Overall, results show a main effect of recent stress for all ethnic groups, and mixed results for the variation in 5-HTTLPR × stress interaction, contingent upon statistical model used. Findings suggest there may be a differential effect of stressors and 5-HTTLPR on depressive symptoms by ethnicity, but further research is needed, particularly when using a haplotype to characterize variation in 5-HTTLPR in population-based sample with a diverse ethnic composition.

DOI10.1007/s10519-015-9740-8
Endnote Keywords

5-HTTLPR/Depressive symptoms/G/Older adults/Race differences/Stressful life events/Genetic analysis

Endnote ID

999999

Citation Key8384
PubMed ID26330209
PubMed Central IDPMC4720538
Grant ListP30AG17265 / AG / NIA NIH HHS / United States
F32AG048681 / AG / NIA NIH HHS / United States
R01 AG030153 / AG / NIA NIH HHS / United States
RC2 AG036495 / AG / NIA NIH HHS / United States
F32 AG048681 / AG / NIA NIH HHS / United States
RC2AG036495 / AG / NIA NIH HHS / United States
RC4 AG039029 / AG / NIA NIH HHS / United States
RC4AG039029 / AG / NIA NIH HHS / United States
U01 AG009740 / AG / NIA NIH HHS / United States
T32 AG000037 / AG / NIA NIH HHS / United States
U01AG009740 / AG / NIA NIH HHS / United States
P30 AG017265 / AG / NIA NIH HHS / United States