Blood lead levels and major depressive disorder, panic disorder, and generalized anxiety disorder in US young adults.
BACKGROUND
Lead is a ubiquitous neurotoxicant, and adverse cognitive and behavioral effects are well-documented in children and occupationally exposed adults but not in adults with low environmental exposure.


OBJECTIVE
To investigate the association of current blood lead levels with 3 common psychiatric disorders-major depression, panic, and generalized anxiety-in young adults.


METHODS
Cross-sectional epidemiologic survey.


METHODS
Nationally representative sample of US adults.


METHODS
A total of 1987 adults aged 20 to 39 years who responded to the National Health and Nutrition Examination Survey (1999-2004).


METHODS
Twelve-month DSM-IV criteria-based diagnoses of major depressive disorder, panic disorder, and generalized anxiety disorder assessed using the Composite International Diagnostic Interview.


RESULTS
The mean (SD) blood lead level was 1.61 (1.72) microg/dL (range, 0.3-37.3 microg/dL) (to convert to micromoles per liter, multiply by 0.0483). Increasing blood lead levels were associated with higher odds of major depression (P = .05 for trend) and panic disorder (P = .02 for trend) but not generalized anxiety disorder (P = .78 for trend) after adjustment for sex, age, race/ethnicity, education status, and poverty to income ratio. Persons with blood lead levels in the highest quintile had 2.3 times the odds of major depressive disorder (95% confidence interval [CI], 1.13-4.75) and 4.9 times the odds of panic disorder (1.32-18.48) as those in the lowest quintile. Cigarette smoking was associated with higher blood lead levels and outcome, but models that excluded current smokers also resulted in significantly increased odds of major depression (P = .03 for trend) and panic disorder (P = .01 for trend) with higher blood lead quintiles.


CONCLUSIONS
In these young adults with low levels of lead exposure, higher blood lead levels were associated with increased odds of major depression and panic disorders. Exposure to lead at levels generally considered safe could result in adverse mental health outcomes.
Bouchard
Maryse F
MF
Département de santé environnementale et santé au travail, Université de Montréal, C.P. 6128 Succursale Centre-Ville, Montréal, QC H3C 3J7, Canada. bouchard.maryse@uqam.ca
Bellinger
David C
DC
Weuve
Jennifer
J
Matthews-Bellinger
Julia
J
Gilman
Stephen E
SE
Wright
Robert O
RO
Schwartz
Joel
J
Weisskopf
Marc G
MG
D000328:Adult; D017677:Age Distribution; D001008:Anxiety Disorders / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D003865:Major Depressive Disorder / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D004781:Environmental Exposure / Q000706:statistics & numerical data; D005260:Female; D006306:Health Surveys; D006801:Humans; D007854:Lead / Q000097:blood*; D016015:Logistic Models; D008297:Male; D009749:Nutrition Surveys; D016017:Odds Ratio; D016584:Panic Disorder / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D014481:United States / Q000453:epidemiology; D055815:Young Adult
D007854:Lead