Table 2.
Study characteristics and outcomes of systematic review and meta-analysis of ROS
| Author (year) | Sample size (N) |
Mean age (SD) (years) |
Gender (male/female) |
Diagnostic method | Disease type | Patient status | Illness duration (years/months) | Medication | Specimen (parameter) | Study outcomes | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Patient | Control | Patient | Control | Patient | Control | ||||||||
| Dietrich-Muszalska et al. [49] (2005) | 31 | 14 | 18–36 | NA | NA | NA | DSM-IV | Paranoid schizophrenia | Inpatients | 4 years | Patients were treated with atypical antipsychotics (risperidone, quetiapine, olanzapine) | Platelets (ROS: superoxide anion, H2O2, singlet oxygen, organic radicals) | ROS level in resting platelets was significantly higher in patients compared to healthy controls (p<0.05). After stimulated with thrombin, platelets from patients (increased 53%) showed decreased chemiluminescence compared to healthy controls (increased 101.5%). |
| Dietrich-Muszalska and Olas [50] (2009) | 35 | 25 | 31.4 (7.3) | 31.0 (6.8) | 21/14 | 15/10 | DSM-IV | Paranoid schizophrenia | Inpatients | 8.9 (4.5) years | Patients were treated with atypical antipsychotics (clozapine, risperidone, olanzapine, quetiapine) | Superoxide anion radicals level was lower in patients compared to healthy controls (p=0.05). They suggested that the reduced level could be due to the formation of RNS. | Superoxide anion radicals level was lower in patients compared to healthy controls (p=0.05). They suggested that the reduced level could be due to the formation of RNS. |
| Melamed et al. [51] (1998) | 29 | 17 | 39.1 (6.3) | 39.4 (6.1) | 19/10 | 9/8 | DSM-III | Schizophrenia | NA | 9.5 (2.4) years | The patients did not take antipsychotics prior to hospitalization | Superoxide anion production was significantly higher (with 34% more production) in patients in comparison to healthy controls (p=0.003). | Superoxide anion production was significantly higher (with 34% more production) in patients in comparison to healthy controls (p=0.003). |
| Sirota et al. [52] (2003) | 18 | 15 | 36.2 (5.8) | 36.8 (5.6) | 15/3 | 12/3 | DSM-IV | Schizophrenia | NA | 11 (9) years | The patients had not taken anti-psychotic medications prior to hospitalization for at least 3 months | Superoxide anion production was significantly higher in patients compared to healthy controls (p=0.012). | Superoxide anion production was significantly higher in patients compared to healthy controls (p=0.012). |
| Szuster-Ciesielska et al. [53] (2008) | 29 | 30 | 48.2 (11.2) | 41.3 (4.4) | 14/15 | 15/15 | DSM-IV | Unipolar depression & bipolar depression | NA | NA | Most of the patients had not taken medication for 3–7 days before the examination; 4 patients received different combinations of amitriptyline, sulpiride, clomipramine, perazine, levomepromazine, or imipramine | Superoxide anion (p<0.05) and H2O2 (p<0.05) productions were significantly higher in patients compared to healthy controls. | Superoxide anion (p<0.05) and H2O2 (p<0.05) productions were significantly higher in patients compared to healthy controls. |
| Alcocer-Gómez et al. [54] (2014) | 40 | 20 | Non-treated=54.4 (10.1); amitriptyline=53.5 (9.8) | 57 (3) | Non-treated=2/18; amitriptyline=1/19 | 2/18 | DSM-IV | Melancholic depression | Outpatients | NA | 20 patients were without treatment; 20 were treated with amitriptyline for 12.1 (2.3) months | Peripheral blood mononuclear cells (mitochondrial superoxide) | Mitochondrial superoxide production was significantly higher in unmedicated patients in comparison to healthy controls (p<0.001). Significantly increased production was also observed in patients treated with amitriptyline (p<0.05 between unmedicated and medicated patients; p<0.001 between medicated patients and healthy controls). |
| Atanackovic et al. [55] (2004) | 10 | 11 | 33.0 (7.4) | 28.0 (4.2) | 2/8 | 4/7 | ICD-10 | Minor depression | Inpatients | NA | Patients were on psychotherapy but not on psychopharmacological treatment | Phagocytes (ROS) | No significant difference in ROS production was observed between patients and healthy controls. |
| Chang et al. [56] (2015) | 35 | 35 | 39.14 (10.23) | 39.37 (8.5) | 13/22 | 11/24 | DSM-IV | First-episode major depressive disorder | Outpatients | NA | Patients were under sertraline treatment for 12 weeks | Blood (superoxide radicals and hydroxyl radicals) | No significant differences in superoxide radicals (p=0.38) and hydroxyl radicals (p=0.26) levels were observed between patients before treatment of sertraline and healthy controls. However, both levels were significantly decreased after treatment of sertraline for 12 weeks (p<0.001). |
| Rybka et al. [57] (2013) | 15 | 19 | 59.7 (1.91) | 62.3 (2.84) | NA | NA | ICD-10 | Recurrent depressive disorder | NA | NA | 60% were treated with selective serotonin reuptake inhibitor (SSRIs), 35% with serotonin-norepinephrine reuptake inhibitor (SNRIs), and 15% with tricyclic antidepressant (TCAs), either as monotherapies or in various combinations | Plasma (H2O2) | Plasma H2O2 concentration was significantly higher in patients in comparison to healthy controls (p=0.005). |
DSM: Diagnostic and Statistical Manual of Mental Disorders, ICD: International Classification of Diseases, ROS: reactive oxygen species, H2O2: hydrogen peroxide, N: number of patients, SD: standard deviation