title: Correlation between age and MMSE in schizophrenia.
abstract: BACKGROUND
  The Mini-Mental State Examination (MMSE) is widely used in schizophrenia, although normative data are lacking in this population. This review and meta-regression analysis studies the effect of aging on MMSE scores in schizophrenic patients.
  
  
  METHODS
  We entered the search terms schizophrenia and MMSE in PubMed and PsychInfo. Bibliographies of pertinent articles were also examined. We included every study presenting the MMSE scores in schizophrenic patients along with a corresponding mean age. We conducted our analyses using simple linear regression weighted for the inverse of within-trial variance of the age variable, thus conferring more importance to studies with narrower age groups.
  
  
  RESULTS
  We identified 56 articles (n = 5,588) published between 1990 and 2012. The MMSE scores of schizophrenic patients decline by approximately 1 point for every four years (y = 34.939-0.247x, 95% Confidence Interval (CI) [-0.304, -0.189], R 2 = 0,545), which is five times the rate in the general population. Institutionalized patients account for a large proportion of this decline (y = 37.603-0.308x, 95% CI [-0.349, -0.267], R 2 = 0.622) whereas community-dwelling patients are relatively stable throughout aging (y = 27.591-0.026x, 95% CI [-0.074, 0.023], R 2 = 0.037).
  
  
  CONCLUSIONS
  Subgroup analyses show different trajectories between institutionalized and outpatients with schizophrenia. The deterioration observed in institutionalized patients may have to do with greater illness severity, heavier medication load, vascular risk factors, and lack of stimulation in institutional settings. Studies documenting the role of these variables would be useful. Cognitive screening tools that assess executive functions would be interesting to study in schizophrenics, as they may reveal more subtle age-related cognitive changes not measured by the MMSE.
authors: Centre de Santé et de Services Sociaux,Institut Universitaire de Gériatrie de Sherbrooke,University of Sherbrooke,Quebec,Canada.
authors: Jean-Robert
authors: JR
authors: Maltais
authors: Department of Geriatric Psychiatry,Douglas Mental Health University Institute,Montreal,Quebec,Canada.
authors: Geneviève
authors: G
authors: Gagnon
authors: Centre de Recherche du CHUS,Centre Hospitalier Universitaire de Sherbrooke,Sherbrooke,Quebec,Canada.
authors: Marie-Pierre
authors: MP
authors: Garant
authors: Centre de Santé et de Services Sociaux,Institut Universitaire de Gériatrie de Sherbrooke,University of Sherbrooke,Quebec,Canada.
authors: Jean-François
authors: JF
authors: Trudel
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D003072:Cognition Disorders / Q000150:complications; D006801:Humans; D007326:Institutionalization / Q000706:statistics & numerical data; D008875:Middle Aged; D009483:Neuropsychological Tests; D010045:Outpatients / Q000523:psychology / Q000706:statistics & numerical data; D012559:Schizophrenia / Q000150:complications / Q000175:diagnosis*; D012565:Schizophrenic Psychology
keywords: Mini-Mental State Examination; aging; cognition (neuro-cognitive functions); review; schizophrenia