It has been hypothesized that lowered antioxidant capacity, which leads to increased oxidative stress, may be involved in the pathophysiology of major depressive disorder (MDD) and anxiety disorders and might be altered by antidepressant treatment.

This study investigated the association of plasma uric acid, the greatest contributor to blood antioxidant capacity, with MDD, generalized anxiety disorder, social phobia, panic disorder, agoraphobia and antidepressants in a large cohort.

Data was derived from the Netherlands Study of Depression and Anxiety including patients with current (n = 1648) or remitted (n = 609) MDD and/or anxiety disorder(s) (of which n = 710 antidepressant users) and 618 controls. Diagnoses were established with the Composite Interview Diagnostic Instrument. Symptom severity was ascertained in all participants with the Inventory of Depressive Symptoms and the Beck Anxiety Inventory. ANCOVA and regression analyses were adjusted for sociodemographic, health and lifestyle variables.

Plasma uric acid was lower in those with current MDD and/or anxiety disorder(s) (adjusted mean 270 μmol/L) compared to those with remitted disorders (280 μmol/L, P < 0.001) or to controls (281 μmol/L, P < 0.001; Cohen's d 0.14). Within patients antidepressants were not associated with uric acid levels. Increasing symptom severity was associated with lower uric acid levels for both depression (β = –0.05, P = 0.001) and anxiety symptoms (β = –0.05, P = 0.004).

This large scale study finds that the antioxidant uric acid is lower in current, but not remitted, MDD or anxiety disorders and in persons with higher symptom severity, suggesting disturbances in redox homeostasis play a role in the pathophysiology of depression and anxiety disorders.

The authors have not supplied their declaration of competing interest.

Oxidative stress has been implicated in the pathophysiology of depression and anxiety disorders and may be influenced by antidepressant use.

This study investigated the association of oxidative stress, measured by plasma levels of F2-isoprostanes and 8-hydroxy-2′-deoxyguanosine (8-OHdG), reflecting oxidative lipid and DNA damage respectively, with major depressive disorder (MDD), generalized anxiety disorder, social phobia, panic disorder, agoraphobia and antidepressant use in a large cohort.

Data was derived from the Netherlands Study of Depression and Anxiety including patients with current (n = 1641) or remitted (n = 610) MDD and/or anxiety disorder(s) (of which n = 709 antidepressant users) and 633 controls. Diagnoses were established with the Composite Interview Diagnostic Instrument. Plasma 8-OHdG and F2-isoprostanes were measured using UHPLC-MS/MS. ANCOVA was performed adjusting for sampling, sociodemographic, health and lifestyle variables.

F2-isoprostanes did not differ between controls and patients, or by antidepressant use. Patients (current or remitted) using antidepressants had lower 8-OHdG (adjusted mean 38.3 pmol/L) compared to patients (current or remitted) without antidepressants (44.7 pmol/L) and controls (44.9 pmol/L, P < 0.001; Cohen's d 0.26). Findings for 8-OHdG were similar over all disorders and all antidepressant types (SSRIs, TCAs, SNRIs; P < 0.001).

Contrary to previous findings this large-scale study did not find increased oxidative stress measured by F2-isoprostanes or 8-OHdG in MDD or anxiety disorders. 8-OHdG levels were lower in antidepressant users, which suggests antidepressants may have antioxidant properties.

The authors have not supplied their declaration of competing interest.

Major depressive disorder (MDD) is a common mood disorder, with a heritability of around 34%. Molecular genetic studies made significant progress and identified genetic markers associated with the risk of MDD; however, progress is slowed down by substantial heterogeneity as MDD is assessed differently across international cohorts. Here, we used a standardized online approach to measure MDD in multiple cohorts in the Netherlands and evaluated whether this approach can be used in epidemiological and genetic association studies of depression.

Within the Biobank Netherlands Internet Collaboration (BIONIC) project, we collected MDD data in eight cohorts involving 31 936 participants, using the online Lifetime Depression Assessment Self-report (LIDAS), and estimated the prevalence of current and lifetime MDD in 22 623 unrelated individuals. In a large Netherlands Twin Register (NTR) twin-family dataset (n ≈ 18 000), we estimated the heritability of MDD, and the prediction of MDD in a subset (n = 4782) through Polygenic Risk Score (PRS).

Estimates of current and lifetime MDD prevalence were 6.7% and 18.1%, respectively, in line with population estimates based on validated psychiatric interviews. In the NTR heritability estimates were 0.34/0.30 (s.e. = 0.02/0.02) for current/lifetime MDD, respectively, showing that the LIDAS gives similar heritability rates for MDD as reported in the literature. The PRS predicted risk of MDD (OR 1.23, 95% CI 1.15–1.32, R2 = 1.47%).

By assessing MDD status in the Netherlands using the LIDAS instrument, we were able to confirm previously reported MDD prevalence and heritability estimates, which suggests that this instrument can be used in epidemiological and genetic association studies of depression.

Oxidative stress has been implicated in the pathophysiology of major depressive disorder (MDD) and anxiety disorders and may be influenced by antidepressant use. This study investigated the association of oxidative stress, measured by plasma levels of F2-isoprostanes and 8-hydroxy-2′-deoxyguanosine (8-OHdG) reflecting oxidative lipid and DNA damage respectively, with MDD, anxiety disorders and antidepressant use in a large cohort.

Data was derived from the Netherlands Study of Depression and Anxiety including patients with current (N = 1619) or remitted (N = 610) MDD and/or anxiety disorder(s) (of which N = 704 antidepressant users) and 612 controls. Diagnoses were established with the Composite International Diagnostic Interview. Plasma 8-OHdG and F2-isoprostanes were measured using LC-MS/MS. ANCOVA was performed adjusted for sampling, sociodemographic, health and lifestyle variables.

F2-isoprostanes did not differ between controls and patients, or by antidepressant use. Patients with current disorders had lower 8-OHdG (mean 42.1 pmol/l, 95% CI 40.4–43.8) compared to controls (45.0 pmol/l, 95% CI 42.9–47.2; p < 0.001) after adjustment for sampling, sociodemographics and lifestyle, but these differences disappeared after further adjustment for antidepressant use (p = 0.562). Antidepressant users had lower 8-OHdG levels (38.2 pmol/l, 95% CI 36.5–39.9) compared to controls (44.9 pmol/l, 95% CI 43.2–46.6; Cohen's d = 0.21, p < 0.001). Results for 8-OHdG were comparable across disorders (MDD and/or anxiety disorders), and all antidepressant types (SSRIs, TCAs, other antidepressants).

Contrary to previous findings this large-scale study found no increased oxidative stress in MDD and anxiety disorders. Antidepressant use was associated with lower oxidative DNA damage, suggesting antidepressants may have antioxidant effects.

There is a paucity of valid, brief instruments for the assessment of lifetime major depressive disorder (MDD) that can be used in, for example, large-scale genomics, imaging or biomarker studies on depression. We developed the LIfetime Depression Assessment Self-report (LIDAS), which assesses lifetime MDD diagnosis according to DSM criteria, and is largely based on the widely used Composite International Diagnostic Interview (CIDI). Here, we tested the feasibility and determined the sensitivity and specificity for measuring lifetime MDD with this new questionnaire, with a regular CIDI as reference.

Sensitivity and specificity analyses of the online lifetime MDD questionnaire were performed in adults with (n = 177) and without (n = 87) lifetime MDD according to regular index CIDIs, selected from the Netherlands Study of Depression and Anxiety (NESDA) and Netherlands Twin Register (NTR). Feasibility was tested in an additional non-selective, population-based sample of NTR participants (n = 245).

Of the 753 invited persons, 509 (68%) completed the LIDAS, of which 419 (82%) did this online. User-friendliness of the instrument was rated high. Median completion time was 6.2 min. Sensitivity and specificity for lifetime MDD were 85% [95% confidence interval (CI) 80–91%] and 80% (95% CI 72–89%), respectively. This LIDAS instrument gave a lifetime MDD prevalence of 20.8% in the population-based sample.

Measuring lifetime MDD with an online instrument was feasible. Sensitivity and specificity were adequate. The instrument gave a prevalence of lifetime MDD in line with reported population prevalences. LIDAS is a promising tool for rapid determination of lifetime MDD status in large samples, such as needed for genomics studies.

Do DSM-IV diagnostic criteria for major depression (MD) in Chinese and Western women perform in a similar manner?

The CONVERGE study included interview-based assessments of women of Han Chinese descent with treated recurrent MD. Using Mplus software, we investigated the overall degree of between-sample measurement invariance (MI) for DSM-IV diagnostic criteria for MD in the CONVERGE sample and samples selected from four major Western studies from the USA and Europe matched to the inclusion criteria of CONVERGE. These analyses were performed one pair at a time. We then compared the results from CONVERGE paired with Western samples to those obtained when examining levels of MI between pairs of the Western samples.

Assuming a single factor model for the nine diagnostic criteria for MD, the level of MI based on global fit indexes observed between the CONVERGE and the four Western samples was very similar to that seen between the Western samples. Comparable results were obtained when using a two-factor structure for MI testing when applied to the 14 diagnostic criteria for MD disaggregated for weight, appetite, sleep, and psychomotor changes.

Despite differences in language, ethnicity and culture, DSM criteria for MD perform similarly in Chinese women with recurrent MD and comparable subjects from the USA and Europe. The DSM criteria for MD may assess depressive symptoms that are relatively insensitive to cultural and ethnic differences. These results support efforts to compare findings from depressed patients in China and Western countries.

To determine the prevalence of psychosocial problems among Dutch children aged 8–12 years and studying its association with risk factors and quality of life.

This study was conducted within the framework of a community-based health study in the north-west region of the Netherlands. The cross-sectional study sample consisted of 2703 children (1392 boys and 1311 girls). Psychosocial problems and quality of life were measured with the extended version of the Strengths and Difficulties Questionnaire (SDQ) and KIDSCREEN-10, respectively. Questionnaires and data about risk factors (parental education level, ethnicity, family structure, income, chronic diseases and life events) were completed by the parents or caregivers.

The prevalence of psychosocial problems (SDQ score ≥14) in the total sample was 10.4%. The prevalence was higher in boys compared with girls (13.9% v. 6.6%, OR = 2.28; 95% CI = 1.75–2.97). Boys had significantly more hyperactivity/inattention, conduct, peer relationship and prosocial behaviour problems compared with girls. Risk factors associated with psychosocial problems were: one or more chronic disease(s), life event(s), a low parental educational level (for boys only) and an income under a modal level. Psychosocial problems were significantly inverse related with quality of life in the total sample (rho = −0.47).

Psychosocial problems are common in children, especially among boys, and are inversely related with children's quality of life. The identified risk factors in this study can be useful for developing targeted prevention strategies aimed at children at high risk for psychosocial problems.