title: Changes in neuropsychological tests and brain metabolism after bariatric surgery.
abstract: BACKGROUND
  The mechanisms by which obesity alters the cerebral function and the effect of weight loss on the brain have not been completely clarified.
  
  
  OBJECTIVE
  The objective of the study was to assess the effect of bariatric surgery on the cognitive function and cerebral metabolism.
  
  
  METHODS
  Seventeen obese women were studied prior to and 24 weeks after bariatric surgery using neuropsychological tests and positron emission tomography.
  
  
  METHODS
  The study was conducted in a reference center for the treatment of obesity of a Brazilian public university.
  
  
  METHODS
  Thirty-three women paired by age and level of education made up two groups: 17 severely obese patients and 16 lean patients. They did not have diabetes mellitus or a family history of dementia.
  
  
  METHODS
  Comparison of performance in neuropsychological tests and cerebral metabolism of the obese women before and after bariatric surgery was measured. The results found at the two moments were compared with those of the women of normal weight.
  
  
  RESULTS
  Women with a mean age of 40.5 years and mean body mass index of 50.1 kg/m(2) when compared with women with mean body mass index of 22.3 kg/m(2) showed increased cerebral metabolism, especially in the posterior cingulate gyrus (P < .004). No difference was found between the groups for the neuropsychological tests. After 24 weeks the cerebral metabolism of the obese women was lower, similar to the lean women, and there was an improvement of executive function, accompanying changes of metabolic and inflammatory parameters.
  
  
  CONCLUSIONS
  Obese women may have increased cerebral metabolism when compared with women of normal weight, and this appears to reverse after weight loss induced by bariatric surgery, accompanied by improved executive function.
authors.affiliation: Obesity and Metabolic Syndrome Group (E.L.M., A.H., M.C.M., M.E.d.M., N.C.H., C.C.), Division of Endocrinology and Metabolism, Clinical Hospital, School of Medicine, University of São Paulo, 05403-000 São Paulo, Brazil; Laboratory of Medical Investigation (LIM-18) (M.C.M., M.E.d.M.), Division of Nuclear Medicine (C.A.B., A.M.N.C., C.R.O., S.P.), Department of Radiology, Division of Metabolic and Bariatric Surgery (M.A.S.), Department of Digestive Surgery, Division of Clinical Immunology and Allergy (E.C.-N.), Department of Clinical Medicine, Integrated Laboratories of Neuropsychology (D.F.), Psychology and Neuropsychology Unit, Institute of Psychiatry, Clinical Hospital, School of Medicine, and Heart Institute (E.C.-N.), University of São Paulo, 01246-903 São Paulo, Brazil.
authors.forename: Emerson Leonildo
authors.initials: EL
authors.lastname: Marques
authors.forename: Alfredo
authors.initials: A
authors.lastname: Halpern
authors.forename: Marcio
authors.initials: M
authors.lastname: Corrêa Mancini
authors.forename: Maria Edna
authors.initials: ME
authors.lastname: de Melo
authors.forename: Nídia Celeste
authors.initials: NC
authors.lastname: Horie
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: Buchpiguel
authors.forename: Artur
authors.initials: A
authors.lastname: Martins Novaes Coutinho
authors.forename: Carla Rachel
authors.initials: CR
authors.lastname: Ono
authors.forename: Silvana
authors.initials: S
authors.lastname: Prando
authors.forename: Marco Aurélio
authors.initials: MA
authors.lastname: Santo
authors.forename: Edécio
authors.initials: E
authors.lastname: Cunha-Neto
authors.forename: Daniel
authors.initials: D
authors.lastname: Fuentes
authors.forename: Cintia
authors.initials: C
authors.lastname: Cercato
mesh_terms: D000328:Adult; D050110:Bariatric Surgery / Q000523:psychology*; D001921:Brain / Q000378:metabolism*; D003071:Cognition; D056344:Executive Function; D005260:Female; D006801:Humans; D008568:Memory; D008875:Middle Aged; D009483:Neuropsychological Tests; D009767:Obesity, Morbid / Q000378:metabolism / Q000523:psychology / Q000601:surgery*; D016896:Treatment Outcome; D015431:Weight Loss