Table 1.
Study | No. patients | Diagnosis | No. controls (relatives) | Cognitive measures | Main results* |
---|---|---|---|---|---|
Green et al.16 | — | 160 | MSIT, WASI (vocabulary, similarities, block design, matrix reasoning) |
|
|
Gong et al.17 | — | 700 | Digital and spatial working memory spans | No association between COMT and digital and spatial working memory spans | |
Blanchard et al.18 | — | 291 | Spatial n-back task | No association between COMT and n-back task | |
Greenwood et al.19 | 87 | Schizophrenia | — | WCST, WAIS-R (digit span) |
|
Wishart et al.20 | — | 95 | TMT A–B, D-KEFS (trail-making subtest) |
|
|
Stokes et al.21 | — | 50 | Spatial n-back, go/no-go, Tower of London tasks | No association between COMT and any cognitive measure | |
Rosa et al.22 | 67 | Schizophrenia and schizoaffective disorder | 186 | Modified Stroop test (manipulating level of required cognitive stability) |
|
Solís-Ortiz et al.23 | — | 74 F | WCST, Stroop test, CPT (test single and AX task), verbal fluency test |
|
|
Uçok et al.24 | 99 | Schizophrenia | — | WCST, CPT (ZA task) |
|
Wilkosc et al.25 | — | 200 | WCST | WCST (percentage of nonperseverative errors): Val/Val Val/met ↓ (in males only) | |
Wirgenes et al.26 | 315 | Schizophrenia-spectrum disorders
|
340 | Bergen n-back task, digit symbol coding test, CVLT, D-KEFS (colour-word interference test, verbal fluency test) |
|
Pomarol-Clotet et al.27 | 42 | Schizophrenia | 31 | N-back task (sequential letter version) | No association between COMT and n-back task |
Dennis et al.28 | — | 496 to 1218 | CANTAB (paired associates learning, spatial working memory, verbal recognition memory—immediate recall, ID/ED, rapid visual processing, spatial span, spatial recognition memory), Green’s story recall (immediate and delayed), TMT A–B, WAIS-III (forward and backward digit span, digit symbol, symbol search), COWAT, semantic fluency, Stroop colour-word interference | No association between COMT and any cognitive measures | |
Van den Bos et al.29 | — | 70 | IGT | Val/Val ↑ | |
Yue et al.30 | — | 21 | N-back task (sequential number version) | Val/Met ↓, Val/Val ↑ | |
Krug et al.31 | — | 80 | Verbal fluency | No association between COMT and verbal fluency | |
Neuhaus et al.32 | 111 | Schizophrenia | — | CPT-IP | Val/Val ↑ |
Prata et al.33 | 42 | Schizophrenia | 48 | Verbal fluency task |
|
Schmack et al.34 | — | 44 | Monetary incentive delay | No association between COMT and monetary incentive delay | |
Sheldrick et al.35 | — | 522 | D2 Test of Attention, MWT-B, LNS, TMT B, verbal fluency, Wechsler Memory Scale (spatial span) |
|
|
Roussos et al.36 | — | 107 | SoC, IGT |
|
|
Roffman et al.37 | 185 | Chronic schizophrenia | — | WCST |
|
Opgen-Rhein et al.38 | 63 | Schizophrenia | 40 | ANT | Schizophranie–controls: Val/Val ValMet ↓ reaction time and ↑ conflict effect scores |
Mata et al.39 | 130 | First-episode nonaffective psychosis | — |
|
No association between COMT and any cognitive domain |
Diaz-Asper et al.40 | 325 | Schizophrenia, schizoaffective disorder | 330 (359) | Spatial n-back task, WCST, CPT 1–9, WAIS-R (short form: arithmetic, similarities, picture completion and digit symbol), ID/ED | Patients, controls, relatives:
|
Bertolino et al.41 | — | 82 | Spatial n-back task, recognition memory paradigm | No association between COMT and any cognitive measures | |
Aguilera et al.42 | — | 521 | WCST, CPT-IP, WMS-R (backward visual span), WAIS III (LNS) |
|
|
Woodward et al.43 | 86 | Schizophrenia | — | ACTT, WCST, WISC-R (mazes), BSRT, CIGT, COWAT, WAIS-R (digit symbol) |
|
MacDonald et al.44 | — | 464 | N-back task (sequential letter version), CPT (AX/DPX tasks) |
|
|
Ehlis et al.45 | 56 | Schizophrenia-spectrum disorders | — | Stroop test, TMT A–B, verbal fluency test |
|
Dickerson et al.46 | 364 | Schizophrenia | — | RBANS: immediate memory (list learning and story memory tasks), visuospatial/constructional (figure copy and line orientation tasks), language (picture naming and semantic fluency tasks), attention (digit span and coding tasks) and delayed memory (list recall, story recall, figure recall and list recognition tasks) | No association between COMT and any of the RBANS index |
Caldú et al.47 | — | 75 | WCST, Conners’ CPT II, n-back task, WAIS (vocabulary) |
|
|
Barnett et al.48 | 822 | Schizophrenia-spectrum disorders | 1088 | WCST |
|
Szöke et al.49 | 66 | Schizophrenia | 50 (57 SCZ) | TMT A–B, WCST | Patients, controls, relatives: no association between COMT and any cognitive measure |
Rybakowski et al.50 | 79 | Schizophrenia | — | WCST |
|
Krabbendam et al.51 | 23 | Schizophrenia | 21 (33) | CPT (Flanker version) | Patients, controls, relatives: Val/Val ↓ (correct responses) |
Han et al.52 | 132M | First-episode schizophrenia, schizoaffective disorder | — | WAIS (information, digit span, vocabulary. arithmetic comprehension, similarity, picture, picture arrangement, block design, object assembly, digit symbol) |
|
Golimbet et al.53 | 124 | Schizophrenia | 116 (79) | Long-term memory, short-term memory, verbal fluency, selectivity of speech relations, calculating with switching over | No association between COMT and any cognitive measure |
Bertolino et al.54 | — | 27 | Recognition memory paradigm | Val/Val ↓ (accuracy at retrieval) | |
Stefanis et al.55 | — | 527 | CPT-IP version | Val/Val Val/Met: higher reaction time variability | |
Ho et al.56 | 159 | Schizophrenia | 84 | WCST, digit span backward, TMT A–B | No association between COMT and any cognitive measure |
Galderisi et al.57 | 106 | Schizophrenia | — | CPT (AX task), WCST | CPT (AX errors) and WSCT (perseverative errors): Val/Val ↓ |
Bruder et al.58 | — | 402 | SDR, WSPT, N-back (sequential letter version), LNS, WCST (n = 246) |
|
|
Blasi et al.59 | — | 23 | Variable attentional control task | Val/Val Val/Met ↓ | |
Rosa et al.60 | 89 | Schizophrenia, schizoaffective disorder, psychotic mood disorder, schizophreniform disorder, brief psychotic disorder, delusional disorder, atypical psychosis | (89) | WCST |
|
Nolan et al.61 | 26 | Schizophrenia, schizoaffective disorder | — | Competing programs task | Val/Val Val/Met ↓ cognitive stability and ↑ cognitive flexibility |
de Frias et al.62 | — | 286 M | Episodic memory (recall test, recognition test), semantic memory (knowledge test, fluency test) |
|
|
Tsai et al.63 | — | 120 F | WCST | No association between COMT and WCST (perseverative errors) | |
Goldberg et al.64 | 74 | Schizophrenia, schizoaffective disorder (depressed type) | 68 (108) | Spatial n-back task, CPT 1–9, WAIS-R (IQ similarities, arithmetic, picture completion and digit symbol) |
|
Malhotra et al.65 | — | 73 | WCST | WCST (perseverative errors): Val/Val Val/Met ↓ | |
Joober et al.66 | 94 | Schizophrenia | 31 | WCST |
|
Bilder1 | 58 | Schizophrenia, schizoaffective disorder | — |
|
Processing speed and attention domain: Val/Val ↓ |
Egan et al.67 | 175 | Schizophrenia | 55 (219) | WCST, WAIS-R, WRAT | Patients, controls, relatives: WSCT (perseverative errors): Val/Val ↓ |
ACTT = Auditory Consonant Trigram Test; ANT = Attention Network Test; BSRT = Buschke Selective Reminding Test; CANTAB = Cambridge Neuropsyhological Test Automated Battery; CIGT = Category Instance Generation Test; COMT = catechol-O-methyltransferase; COWAT = Controlled Oral Word Association Test; CPT = Continuous Performance Test; CPT-IP = Continuous Performance Test, Identical Pairs version; CVLT = California Verbal Learning Test; DAT = dopamine transporter; D-KEFS = Delis–Kaplan Executive Function System; F = female; DPX = Dot Pattern Expectancy task; ID/ED = intradimensional/extradimensional shift task; IGT = Iowa Gambling Task; LNS = letter and number sequencing; M = male; MSIT = Multi-Source Interference Task; MWT-B = Mehrfachwahl-Wortschatz-Intelligenztest B; RBANS = Repeatable Battery for the Assessment of Neuropsychological Status; SDR = Spatial Delayed Response; SoC = Stockings of Cambridge; TMT = Trail Making Test; WAIS = Wechsler Adult Intelligence Scale; WAIS III = Wechsler Adult Intelligence Scale-III; WAIS-R = Wechsler Adult Intelligence Scale-Revised; WASI = Wechsler Abbreviated Scale of Intelligence; WCST = Wisconsin Card sorting Test; WISC-R = Wechsler Intelligence Scale for Children-Revised; WMS-R = Wechsler Memory Scale-Revised; WRAT = Wide Range Achievement Test; WSPT = Word Serial Position Test.