METHOD: Based on a preregistered protocol (PROSPERO: CRD42021239635), PubMed, Web of Knowledge/Science, Ovid MEDLINE, Embase, and APA PsycInfo databases were searched until April 21, 2021, to identify empirical studies reporting indices of autonomic nervous system (ANS) functioning in youths meeting DSM (version III, IV, IV-TR, 5 or 5-TR) or International Classification of Diseases (ICD) (version 9 or 10) criteria for any psychopathological/neurodevelopmental condition and assessed for ED with a validated scale. Eligible outcomes included correlation coefficients between ED and ANS measures or differences in ANS measures between youths with and without ED. Study quality was assessed with the Appraisal tool for Cross-Sectional Studies (AXIS) and the Newcastle-Ottawa Scale (NOS) for cohort studies. Random-effects meta-analyses were used for data synthesis.
RESULTS: There were 12 studies (1,016 participants) included in the descriptive review and 9 studies (567 participants) included in the meta-analyses. No evidence of a significant association between ED and altered cardiac or electrodermal functioning was found. However, exploratory meta-regressions suggested a possible association between reduced resting-state cardiac vagal control and increased ED.
CONCLUSION: This study did not find evidence of an association between ED and autonomic dysfunction. However, preliminary evidence that reduced vagal control at rest might be a transdiagnostic marker of ED in young people was found. Additional studies comparing autonomic measures in youths with and without ED are needed and should also assess the effects of interventions for ED on ANS functioning.
STUDY PREREGISTRATION INFORMATION: Systematic Review and Meta-Analysis: Is Autonomic Nervous System Functioning Atypical in Children and Adolescents With Emotional Dysregulation? https://www.crd.york.ac.uk/prospero/; CRD42021239635.
OBJECTIVES: The objectives of this systematic review and meta-analysis were to assess the efficacy, acceptability, and tolerability of nonstimulants in adults with ADHD.
METHODS: Data sources, searches, and study selection were based on a previously published network meta-analysis of randomized clinical trials (RCTs) by Cortese at al. (Lancet Psychiatry 5(9):727-738, 2018), which we updated in March 2022. Specifically, we searched PubMed, BIOSIS Previews, CINAHL, the Cochrane Central Register of Controlled Trials, EMBASE, ERIC, MEDLINE, PsycINFO, OpenGrey, Web of Science Core Collection, ProQuest Dissertations and Theses (UK and Ireland), ProQuest Dissertations and Theses (abstracts and international), and the WHO International Trials Registry Platform, including ClinicalTrials.gov for double-blind RCTs with a placebo arm, lasting at least one week, including adults with a diagnosis of ADHD based on DSM-III, DSM-III-R, DSM-IV(TR), DSM-5 or ICD-9- or 10, and reporting data on efficacy, tolerability (drop-out due to side effects) and acceptability (drop-out due to any cause) of guanfacine, clonidine, or atomoxetine. Additionally, we searched for RCTs of viloxazine extended release (ER), approved for ADHD in 2021. Random-effects meta-analyses were conducted, and the risk of bias for individual RCTs was assessed using the Cochrane Risk of Bias tool.
RESULTS: We included 18 studies in the meta-analyses (4308 participants) plus one additional study in the narrative synthesis (374 participants). The meta-analysis showed that atomoxetine (15 RCTs) (Hedge's g = - 0.48, 95% CI [- 0.64; - 0.33]), guanfacine (two RCTs) (Hedge's g = - 0.66, 95% CI [- 0.94; - 0.38]) and viloxazine ER (one RCT) were significantly more efficacious than placebo. Atomoxetine was less well tolerated than placebo, while tolerability of guanfacine and viloxazine ER could not be meta-analysed, since only one study, for each medication, reported on it.
CONCLUSIONS: All investigated nonstimulants were more efficacious in the treatment of ADHD in adults, than placebo, while the placebo had better acceptability and tolerability.
PROTOCOL: https://osf.io/5vnmt/?view_only=2bf87ed12ba94645babedceeee4c0120 .
METHOD: Based on a pre-registered protocol (PROSPERO: CRD42022328485), we searched PubMed, Web of Knowledge/Science, Ovid Medline, Embase and APA PsycINFO up to 5th February 2022, with no language/type of document restrictions. We included observational studies 1) reporting at least one measure of vision in people of any age with a diagnosis of ASD based on DSM or ICD criteria, or ADOS; or 2) reporting the prevalence of ASD in people with and without vision disorders. Study quality was assessed with the Appraisal tool for Cross-Sectional Studies (AXIS). Random-effects meta-analyses were used for data synthesis.
RESULTS: We included 49 studies in the narrative synthesis and 46 studies in the meta-analyses (15,629,159 individuals distributed across multiple different measures). We found meta-analytic evidence of increased prevalence of strabismus (OR = 4.72 [95% CI: 4.60, 4.85]) in people with versus those without ASD (non-significant heterogeneity: Q = 1.0545, p = 0.7881). We also found evidence of increased accommodation deficits (Hedge's g = 0.68 [CI: 0.28, 1.08]) (non-significant heterogeneity: Q = 6.9331, p = 0.0741), reduced peripheral vision (-0.82 [CI: -1.32, -0.33]) (non-significant heterogeneity: Q = 4.8075, p = 0.4398), reduced stereoacuity (0.73 [CI: -1.14, -0.31]) (non-significant heterogeneity: Q = 0.8974, p = 0.3435), increased color discrimination difficulties (0.69 [CI: 0.27,1.10]) (non-significant heterogeneity: Q = 9.9928, p = 0.1890), reduced contrast sensitivity (0.45 [CI: -0.60, -0.30]) (non-significant heterogeneity: Q = 9.9928, p = 0.1890) and increased retinal thickness (=0.29 [CI: 0.07, 0.51]) (non-significant heterogeneity: Q = 0.8113, p = 0.9918) in ASD.
DISCUSSION: ASD is associated with some self-reported and objectively measured functional vision problems, and structural alterations of the eye, even though we observed several methodological limitations in the individual studies included in our meta-analyses. Further research should clarify the causal relationship, if any, between ASD and problems of vision during early life.
PROSPERO REGISTRATION: CRD42022328485.
METHODS: Based on a preregistered protocol (CRD42022377671), we searched PubMed, Medline, Ovid Embase, APA PsycINFO and Web of Science on 15th August 2022, with no language/type of document restrictions. We included studies reporting accuracy measures (e.g. sensitivity, specificity, or Area under the Receiver Operating Characteristics Curve, AUC) for QbTest in discriminating between people with and without DSM/ICD ADHD diagnosis. Risk of bias was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2). A generic inverse variance meta-analysis was conducted on AUC scores. Pooled sensitivity and specificity were calculated using a random-effects bivariate model in R.
RESULTS: We included 15 studies (2,058 participants; 48.6% with ADHD). QbTest Total scores showed acceptable, rather than good, sensitivity (0.78 [95% confidence interval: 0.69; 0.85]) and specificity (0.70 [0.57; 0.81]), while subscales showed low-to-moderate sensitivity (ranging from 0.48 [0.35; 0.61] to 0.65 [0.52; 0.75]) and moderate-to-good specificity (from 0.65 [0.48; 0.78] to 0.83 [0.60; 0.94]). Pooled AUC scores suggested moderate-to-acceptable discriminative ability (Q-Total: 0.72 [0.57; 0.87]; Q-Activity: 0.67 [0.58; 0.77); Q-Inattention: 0.66 [0.59; 0.72]; Q-Impulsivity: 0.59 [0.53; 0.64]).
CONCLUSIONS: When used on their own, QbTest scores available to clinicians are not sufficiently accurate in discriminating between ADHD and non-ADHD clinical cases. Therefore, the QbTest should not be used as stand-alone screening or diagnostic tool, or as a triage system for accepting individuals on the waiting-list for clinical services. However, when used as an adjunct to support a full clinical assessment, QbTest can produce efficiencies in the assessment pathway and reduce the time to diagnosis.
METHOD: Based on a pre-registered protocol (PROSPERO: CRD42021256352), we searched PubMed, Web of Knowledge/Science, Ovid Medline, Embase and APA PsycINFO up to 16th November 2021, with no language/type of document restrictions. We included observational studies reporting at least one measure of vision in people of any age meeting DSM/ICD criteria for ADHD and in people without ADHD; or the prevalence of ADHD in people with and without vision disorders. Study quality was assessed with the Appraisal tool for Cross-Sectional Studies (AXIS). Random effects meta-analyses were used for data synthesis.
RESULTS: We included 42 studies in the narrative synthesis and 35 studies in the meta-analyses (3,250,905 participants). We found meta-analytic evidence of increased risk of astigmatism (OR = 1.79 [CI: 1.50, 2.14]), hyperopia and hypermetropia (OR = 1.79 [CI: 1.66, 1.94]), strabismus (OR = 1.93 [CI: 1.75, 2.12]), unspecified vision problems (OR = 1.94 [CI: 1.38, 2.73]) and reduced near point of convergence (OR = 5.02 [CI: 1.78, 14.11]); increased lag (Hedge's g = 0.63 [CI: 0.30, 0.96]) and variability (Hedge's g = 0.40 [CI: 0.17, 0.64]) of the accommodative response; and increased self-reported vision problems (Hedge's g = 0.63 [CI: 0.44, 0.82]) in people with ADHD compared to those without ADHD (with no significant heterogeneity). We also found meta-analytic evidence of no differences between people with and without ADHD on retinal nerve fiber layer thickness (Hedge's g = -0.19 [CI: -0.41, 0.02]) and refractive error (Hedge's g = 0.08 [CI: -0.26, 0.42]) (with no significant heterogeneity).
DISCUSSION: ADHD is associated with some self-reported and objectively ascertained functional vision problems, but not with structural alterations of the eye. Further studies should clarify the causal relationship, if any, between ADHD and problems of vision.
TRIAL REGISTRATION: PROSPERO registration: CRD42021256352.
AREAS COVERED: We first discuss the definition of biomarkers and the necessary research steps from discovery to implementation. We then provide a broad overview of research studies on candidate diagnostic biomarkers in ADHD encompassing genetic/epigenetic, biochemical, neuroimaging, neurophysiological and neuropsychological techniques. Finally, we critically appraise current limitations in the field and suggest possible ways forward.
EXPERT OPINION: Despite the large number of studies and variety of techniques used, no promising biomarkers have been identified so far. Clinical and biological heterogeneity as well as methodological limitations, including small sample size, lack of standardization, confounding factors, and poor replicability, have hampered progress in the field. Going forward, increased international collaborative efforts are warranted to support larger and more robustly designed studies, develop multimodal datasets to combine biomarkers and improve diagnostic accuracy, and ensure reproducibility and meaningful clinical translation.
AREAS COVERED: The authors searched PubMed, Medline, PsycInfo, Embase+Embase Classic, Web of Sciences databases, and clinicaltrials.gov up to 4 January 2024, for randomized controlled trials (RCTs) of any intervention for sleep disorders associated with ADHD. They retained 16 RCTs (eight on pharmacological and eight on non-pharmacological interventions), supporting behavioral intervention and melatonin, and nine ongoing RCTs registered on clinicaltrials.gov.
EXPERT OPINION: The pool of RCTs testing interventions for sleep disorders in individuals with ADHD is expanding. However, to inform clinical guidelines, there is a need for additional research in several areas, including 1) RCTs based on a precise phenotyping of sleep disorders; 2) pragmatic RCTs recruiting neurodevelopmental populations representative of those seen in clinical services; 3) trials testing alternative interventions (e.g. suvorexant or light therapy) or ways to deliver them (e.g. online); 4) sequential and longer-term RCTs; 5) studies testing the impact of sleep interventions on outcomes other than sleep; 6) and implementation of advanced evidence synthesis and precision medicine approaches.