title: Obesity, smoking, and frontal brain dysfunction.
abstract: Obesity, smoking, and conduct problems have all been associated with decrements in brain function. However, their additive and interactive effects have rarely been examined. To address the deficiency, we studied P300a and P300b electroencephalographic potentials in 218 women grouped by the presence versus absence of: (1) a BMI > or = 30 kg/m(2); (2) recent smoking; and (3) > or = 2 childhood conduct problems. Analyses revealed smaller P300a and P300b amplitudes over the posterior scalp among recent smokers versus nonsmokers. No corresponding group differences were found in P300 latencies or frontal scalp amplitudes. The most interesting analysis result was an interaction between conduct problems and obesity limited to the frontally generated P300a component: its latency was significantly greater in women with both attributes than in those with either or neither attribute. An exploratory ANOVA, substituting the genotype of a GABRA2 SNP for conduct problems, also demonstrated an interaction with obesity affecting P300a latency. It is hypothesized that conduct problems, and a conduct-problem-associated GABRA2 genotype, decrease the age-of-onset and/or increase the lifetime duration of obesity. As a result, they may potentiate the adverse effects of obesity on frontal white matter and thereby increase P300a latency. Smoking may affect brain function by a different mechanism to reduce posterior scalp P300a and P300b amplitudes while preserving frontal scalp P300a latency and amplitude.
authors: Department of Psychiatry, University of Connecticut School of Medicine, Farmington, Connecticut 06030-2103, USA. bauer@psychiatry.uchc.edu
authors: Lance
authors: L
authors: Bauer
authors: Danielle
authors: D
authors: Dick
authors: Laura
authors: L
authors: Bierut
authors: Kathleen
authors: K
authors: Bucholz
authors: Howard
authors: H
authors: Edenberg
authors: Samuel
authors: S
authors: Kuperman
authors: John
authors: J
authors: Kramer
authors: John
authors: J
authors: Nurnberger
authors: Sean
authors: S
authors: O'Connor
authors: John
authors: J
authors: Rice
authors: John
authors: J
authors: Rohrbaugh
authors: Marc
authors: M
authors: Schuckit
authors: Jay
authors: J
authors: Tischfield
authors: Bernice
authors: B
authors: Porjesz
authors: Victor
authors: V
authors: Hesselbrock
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002540:Cerebral Cortex / Q000503:physiopathology; D019955:Conduct Disorder / Q000150:complications / Q000235:genetics / Q000503:physiopathology*; D018913:Event-Related Potentials, P300 / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D009765:Obesity / Q000150:complications / Q000503:physiopathology*; D020641:Polymorphism, Single Nucleotide; D011963:Receptors, GABA-A / Q000235:genetics / Q000502:physiology*; D012907:Smoking / Q000503:physiopathology*
chemical_list: C484841:GABRA2 protein, human; D011963:Receptors, GABA-A