PUBLIC HEALTH SIGNIFICANCE OF NEUROTICISM

1. Benjamin B. Lahey, University of Chicago PUBLIC HEALTH SIGNIFICANCE OF NEUROTICISM Student Leadership Presentation by Travis J. Pashak

2. Presentation Overview • What IS neuroticism? • Association with disorders • Genetic and Environmental influences • Causal links to adverse outcomes • Prevention • Future research

3. What is neuroticism?

4. What is neuroticism? • “Relatively stable tendencies to respond with negative emotions to threat, frustration, or loss.” – Lahey, B. B. • “An enduring tendency to experience negative emotional states” – Wikipedia

5. Characteristics of Neuroticism • Levels peak in late adolescence • Moderate decline through adulthood • Across rank-order individuals, stable • Somewhat higher in low SES groups • Slightly higher in females

6. Association with Mental Disorders Neuroticism is strongly associated with: • Somatoform disorders • Eating disorders • Schizophrenia • Substance use disorders • Depression and more…

7. Association with Mental Disorders

8. Associated AND Predictive • Higher neuroticism predicts a 90%-100% greater likelihood of developing major depression in the next 12 months • High neuroticism scores at age 16 predicted 93% greater likelihood of developing schizophrenia • Suicide risk between ages 15-21 was 225% greater for 14 year-olds in the highest neuroticism quartile vs. the lowest

9. Association with Physical Health Neuroticism is associated with: • Unfounded somatic complaints • Cardiovascular disease • Atopic eczema • Asthma • Irritable Bowel Syndrome

10. Associated AND Predictive • Neuroticism significantly predicts longevity in normative samples. • Neuroticism predicts morbidity in individuals with chronic diseases and cancer. • Neuroticism predicts health deterioration in individuals with Type I Diabetes and those with cardiac disease.

11. Neuroticism and Quality of Life Neuroticism is inversely related to: • Marital satisfaction • Occupational success • Overall quality of life All things considered, higher neuroticism “predicts shorter, less happy, less healthy, and less successful lives to a meaningful extent.” - Lahey

12. What causes neuroticism? • Evidence exists for both genetic influences on neuroticism and environmental influences. • Although we know that nature and nurture’s effects are intertwined, let’s explore their roots separately.

13. Genetic Influences • Neuroticism is largely heritable, peaking in early adolescence and early adulthood • During that period there are little sex differences, but with age women have more heritability than men

14. Genetic Influences • A polymorphism of the serotonin transporter has been shown to play a part in neuroticism development. • Called “5-HTTLPR,” this polymorphism is of special interest because: • It indirectly influences serotonin transporters • It could be a target for medication since we’ve seen progress using SSRI’s

15. Genetic Influences • Neuroticism scores are slightly but significantly higher in persons with at least one short 5-HTTLPR allele • fMRI has shown variations in 5-HTTLPR are linked to differences in amygdala activation in reaction to threats • However, Genome-wide linkage studies have been inconsistent (see link at end for more on GWAS)

16. Environmental Influences • Some correlations between neuroticism scores in adults and retrospective recall of their upbringing include: • Being abused as a child • Lack of religiosity in the family • Low parental involvement • This area is in definite need of prospective longitudinal research

17. Causal Links to AdverseOutcomes • Currently there are three working models of the causal links between neuroticism and mental disorders. • First, let’s briefly review some models from class: 1) 2) 3) 4)

18. Causal Link Models #1 Overlapping Genetic Influences • This model explains the correlation between mental disorders and neuroticism by showing that they are influenced by the same genes. *Multiformity *Mediator

19. Causal Link Models #2 Neuroticism, stressful events, and social support • This model explains the link between neuroticism and mental disorders by pointing to an indirect relationship of life events and social support

20. Causal Link Models #3 Neuroticism and Emotional Reactivity to Stressful Life Events • This model is probably the most fundamental of the three, stating that persons with high neuroticism respond more negatively to stimuli which then affects their mental health.

21. Neuroticism and Physical Health • Evidence is growing that neuroticism moderates the magnitude of physiological responses to stressors. • Other plausible examples? White board!

22. Neuroticism and Prevention • Ultimately, knowledge about neuroticism isn’t helpful to public health unless we can use it to prevent or treat problems. • Lahey suggests three potential prevention plans, but first can we think of any of our own?

23. Neuroticism and Prevention #1 Neuroticism Screenings • Those with high scores could be advised to seek further individual check-ups for both medical and mental issues which are commonly associated • However, the risks must be assessed including: • Money spent vs. positive impact on public health • False-positives leading to stigma or unnecessary worry • People largely already aware of their associated symptoms

24. Neuroticism and Prevention #2 Reduce population levels of neuroticism to indirectly reduce associated problems • To date, no interventions specifically for neuroticism have been developed but they seem feasible. • Implemented in group settings, could be very cost-effective

25. Neuroticism and Prevention #3 Routinely Assess for Neuroticism in Persons Already Showing the Associated Conditions • For those who appear to deteriorate more quickly when with high neuroticism, could improve longevity -Diabetes -Cardiovascular Disease

26. Where to Start Searching? • If we aim to identify populations with high levels of neuroticism and provide treatment & prevention of associated conditions, where do we start? • Geography and Personality: Regional Differences

27. Future Directions for Research • Further testing of the causal models • Combine evidence to construct comprehensive multimodal perspectives • Invest in a greater understanding of genetic and environmental influences • Create working models for each disorder of the multifaceted causal pathways

28. Helpful Online Resources • Neuroticism • 5-HTTLPR • Longevity • Regional Differences • Genome-Wide Association Study THANK YOU FOR YOUR ATTENTION AND PARTICIPATION!