TY - JOUR
T1 - The Longitudinal Course of Schizophrenia Across the Lifespan
T2 - Clinical, Cognitive, and Neurobiological Aspects
AU - Heilbronner, Urs
AU - Samara, Myrto
AU - Leucht, Stefan
AU - Falkai, Peter
AU - Schulze, Thomas G.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - Despite several decades of research, our knowledge of the long-term course of schizophrenia (SZ) is hampered by a lack of homogeneity of both research methods and phenotypic definitions of SZs course. We provide a comprehensive review of the course of SZ by applying stringent methodological and diagnostic study-selection criteria. We report on positive and negative symptoms, cognition, and findings obtained by neuroimaging. In addition, we perform a meta-analysis of longitudinal studies of cognition in humans. We selected 35 human studies focusing on a narrow SZ phenotype, employing a follow-up duration of six months or more and consistent methodology at the different measurement points. For the meta-analysis on global cognitive change, eight and four studies were used to compare SZ to healthy and psychiatric controls, respectively. We find that the course of SZ is characterized by a constancy or even improvement of positive and negative symptoms and by fairly stable cognitive impairment, reflecting structural frontal and temporal cortical pathology. Progressive changes of the frontal cortex appear to develop in parallel with changes in symptomatology and executive impairment. Despite stable differences in cognition between patients and controls over the time intervals studied, high heterogeneity in the magnitude of effect sizes is present, and age is identified as one of its potential sources. Meta-regression shows these magnitudes to depend on the age at study inclusion. For future research, a combination of longitudinal and cross-sectional research designs is warranted to better account for potential cohort effects.
AB - Despite several decades of research, our knowledge of the long-term course of schizophrenia (SZ) is hampered by a lack of homogeneity of both research methods and phenotypic definitions of SZs course. We provide a comprehensive review of the course of SZ by applying stringent methodological and diagnostic study-selection criteria. We report on positive and negative symptoms, cognition, and findings obtained by neuroimaging. In addition, we perform a meta-analysis of longitudinal studies of cognition in humans. We selected 35 human studies focusing on a narrow SZ phenotype, employing a follow-up duration of six months or more and consistent methodology at the different measurement points. For the meta-analysis on global cognitive change, eight and four studies were used to compare SZ to healthy and psychiatric controls, respectively. We find that the course of SZ is characterized by a constancy or even improvement of positive and negative symptoms and by fairly stable cognitive impairment, reflecting structural frontal and temporal cortical pathology. Progressive changes of the frontal cortex appear to develop in parallel with changes in symptomatology and executive impairment. Despite stable differences in cognition between patients and controls over the time intervals studied, high heterogeneity in the magnitude of effect sizes is present, and age is identified as one of its potential sources. Meta-regression shows these magnitudes to depend on the age at study inclusion. For future research, a combination of longitudinal and cross-sectional research designs is warranted to better account for potential cohort effects.
KW - diagnosis
KW - imaging
KW - longitudinal
KW - neuropsychology
KW - psychosis
KW - schizophrenia
UR - http://www.scopus.com/inward/record.url?scp=84962528018&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84962528018&partnerID=8YFLogxK
U2 - 10.1097/HRP.0000000000000092
DO - 10.1097/HRP.0000000000000092
M3 - Article
C2 - 26954596
AN - SCOPUS:84962528018
VL - 24
SP - 118
EP - 128
JO - Harvard Review of Psychiatry
JF - Harvard Review of Psychiatry
SN - 1067-3229
IS - 2
ER -