Table 1.
Studies on genetics in the context of cognitive remediation therapies in schizophrenia.
| Sample | Intervention/approach | Gene | Variants | Comparisons | Results | Effect size | CTAM index | |
|---|---|---|---|---|---|---|---|---|
| Bosia et al. (2007) | SCH = 50 (CRT: 27/SRT: 23) |
Cogpack Software Drill-and-practice |
COMT | rs4680 | Baseline/post-treatment differences in cognition between Val/Val and Met-carriers | Greater improvement of executive functions and quality of life in Met carriers | Met carriers EF = 0.7 QoL = 0.50 |
57 |
| Greenwood et al. (2011) | SCH = 87 | Cognitive Remediation Therapy Strategy-based |
COMT | rs4680 | Baseline/post-treatment differences in cognition between the three genotype groups (Met/Met, Val/Met, Val/Val) | No effect of COMT genotype on CRT improvement | No effect | 77 |
| Panizzutti et al. (2013) | SCH = 48 | Computerized cognitive training exercises Drill and practice |
COMT | rs165599, rs9265, rs5993891, rs758373, rs2239395, rs2240713, rs739368, rs1544325 | Association between variation in the COMT gene and global cognition improvement | Cumulative effect of COMT SNPs on cognitive improvement | N.A. | 77 |
| Mak et al. (2013) | SCH = 41 HC = 40 |
RehaCom software Drill and practice |
COMT BDNF |
rs4680 rs6265 |
Baseline/post-treatment differences in cognition between Val/Val and Met-carriers | No significant effects | No effect | 40 |
| Bosia et al., 2014a, Bosia et al., 2014b | SCH = 86 |
Cogpack Software Drill-and-practice |
COMT 5-HT1A-R |
rs4680 rs6295 |
A general linear model analysis, with COMT and 5-HT1A-R genotypes as categorical predictors | COMT Val/Val plus 5-HT1A G/G: lower improvement of EF. | COMT Met Carriers plus 5-HT1A G/G group EF = 0.9 |
48 |
| Bosia et al., 2014a, Bosia et al., 2014b | SCH = 98 |
Cogpack Software Drill-and-practice |
COMT | rs4680 | Baseline/post-treatment differences in cognition between Val/Val and Met-carriers | Met carriers: greater improvement in processing speed in patients treated with D2 blockers | Met Carriers PS = 0.44 |
48 |
| Burton et al. (2015) | SCH = 41 | Compensatory Cognitive Training Strategy-based |
COMT | rs4680 | COMT genotype as a predictor of response | No effect of COMT genotype on cognitive improvement | No effect | 40 |
| Lindenmayer et al. (2015) | SCH = 145 |
Cogpack Software Drill and practice |
COMT | rs4680 | Baseline/post-treatment differences in cognition between the three genotype groups (Met/Met, Val/Met, Val/Val) | Met carriers: greater improvements in multiple cognitive domains | Met/Met PS = 0.310 A/V = 0.021 WM = 0.028 VL = 0.183 VIL = 0.314 R-PS = 0.029 GCI = 0.024 |
56 |
| Penadés et al. (2017) | SCH = 70 (CRT: 35/SST: 35) HC: 15 |
Cognitive Remediation Therapy Strategy-based |
BDNF | rs6265 | Differences in BDNF-serum levels between Val/Val and Met-carriers after CRT | Val/Val: higher BDNF serum levels after cognitive treatment Met-carriers: no changes |
Week-4 = 0.54 After CRT = 0.64 |
70 |
| Spangaro et al. (2018) | SCH = 88 |
Cogpack Software Drill-and-practice |
SLC1A2 | (EAAT2) rs4354668 | Differences between T/T homozygote and carriers of the G allele | T/T: greater Working Memory improvements after cognitive treatment Interaction between genotype and therapy on EF outcome |
T/T WM = 0.69 (3 months); 0.64 (6 months) T/T not treated with clozapine EF = 0.68 |
49 |
CTAM: Clinical Trials Assessment Measure; SCH: Schizophrenia; HC: Healthy controls; CRT: Cognitive Remediation Therapy; SST: Social Skills Training; SRT: Standard Rehabilitation Treatment; COMT: Catechol-O-methyltransferase; BDNF: Brain derived neurotrophic factor, SLC1A2: Excitatory amino acid transporter 2; 5-HT1A-R: 5-hydroxytryptamine receptor. EATT2: Excitatory amino acid transporter 2; PS: Psychomotor Speed; A/V: Attention/vigilance; VL: Verbal Learning; VIL: Visual Learning; R-PS: Reasoning and Problem Solving; EF: Executive functions; GCI: Global Composite Index; QoL: Quality of Life.