Do phenotypic characteristics, parental psychopathology, family functioning, and environmental stressors have a role in the response to methylphenidate in children with attention-deficit/hyperactivity disorder? A naturalistic study from a developing country.

Little is known about the effect of clinical characteristics, parental psychopathology, family functioning, and environmental stressors in the response to methylphenidate in children with attention-deficit/hyperactivity disorder (ADHD) followed up in a naturalistic setting. Data from cultures outside the United States are extremely scarce. This is a longitudinal study using a nonrandom assignment, quasi-experimental design. One hundred twenty-five children with ADHD were treated with methylphenidate according to standard clinical procedures, and followed up for 6 months. The severity of ADHD symptoms was assessed by the Swanson, Nolan, and Pelham rating scale. In the final multivariate model, ADHD combined subtype (P < 0.001) and comorbidity with oppositional defiant disorder (P = 0.03) were both predictors of a worse clinical response. In addition, the levels of maternal ADHD symptoms were also associated with worse prognosis (P < 0.001). In the context of several adverse psychosocial factors assessed, only undesired pregnancy was associated with poorer response to methylphenidate in the final comprehensive model (P = 0.02). Our study provides evidence for the involvement of clinical characteristics, maternal psychopathology, and environmental stressors in the response to methylphenidate. Clinicians may consider adjuvant strategies when negative predictors are present to increase the chances of success with methylphenidate treatment.

Synaptic targets of photoreceptors specialized to detect color and skylight polarization in Drosophila.

Color and polarization provide complementary information about the world and are detected by specialized photoreceptors. However, the downstream neural circuits that process these distinct modalities are incompletely understood in any animal. Using electron microscopy, we have systematically reconstructed the synaptic targets of the photoreceptors specialized to detect color and skylight polarization in Drosophila, and we have used light microscopy to confirm many of our findings. We identified known and novel downstream targets that are selective for different wavelengths or polarized light, and followed their projections to other areas in the optic lobes and the central brain. Our results revealed many synapses along the photoreceptor axons between brain regions, new pathways in the optic lobes, and spatially segregated projections to central brain regions. Strikingly, photoreceptors in the polarization-sensitive dorsal rim area target fewer cell types, and lack strong connections to the lobula, a neuropil involved in color processing. Our reconstruction identifies shared wiring and modality-specific specializations for color and polarization vision, and provides a comprehensive view of the first steps of the pathways processing color and polarized light inputs.

Do hyperactive symptoms matter in ADHD-I restricted phenotype?

The objective of the current study was to evaluate a proposed restrictive inattentive type of Attention Deficit Hyperactivity Disorder (ADHD) by comparing clinical correlates among youths with ADHD inattentive type (ADHD-I) as a function of the number of hyperactivity symptoms presented (none vs. 3 or less) and controls (individuals without ADHD). The sample for this community-based study was comprised of youths aged 6 to 18 years from 12 public schools in Porto Alegre, Brazil. ADHD-I groups had lower levels of adaptive functioning (p < .001) and a higher occurrence of familial ADHD (p < .001) when compared with the controls. There was no significant difference between the two ADHD-I groups. Also, both ADHD-I groups had higher rates of oppositional defiant disorder than controls (p < .001) without significant difference between them. For generalized anxiety disorder and social phobia, only the ADHD-I without HI group showed significant differences compared to controls.

Do sluggish cognitive tempo symptoms predict response to methylphenidate in patients with attention-deficit/hyperactivity disorder-inattentive type?

In this naturalistic study, we assessed the effect of sluggish cognitive tempo (SCT) symptoms in the response to methylphenidate (MPH) in 88 children and adolescents with attention-deficit/hyperactivity disorder-Inattentive Type (ADHD-I) according to Diagnostic and Statistical Manual of Mental Disorders, 4(th) edition (DSM-IV) criteria. SCT symptoms were assessed in these subjects by means of the Child Behavior Checklist (CBCL) scale. The response to MPH after 1 month of treatment was assessed by parental scores in the Swanson, Nolan, and Pelham Questionnaire-Version IV (SNAP-IV) scale. No significant differences were found between subjects with and without SCT symptoms in the response to MPH either assessing presence of SCT symptoms categorically (at least 1 symptom) or dimensionally (p < 0.5 for both analyses; effect size [ES] = 0.24). Our findings corroborate previous phenotypic data suggesting that SCT symptoms do not define a clinically relevant type of ADHD-I.

Switching from methylphenidate immediate release to MPH-SODAS in attention-deficit/hyperactivity disorder.

OBJECTIVE: To assess ADHD symptoms after switching from Methylphenidate Immediate-release (MPH-IR) to Methylphenidate Spheroidal Oral Drug Absorption System (MPH-SODAS) in clinically stable patients with ADHD and to identify predictors of dissatisfaction with MPH-SODAS. METHODS: This is an 8-week open clinical trial. Patients were assigned to MPH-SODAS according to their pre-study dose of MPH-IR. Assessments at baseline were conducted using the Swanson, Nolan, and Pelham-IV Questionnaire (SNAP-IV), and the Barkley's Side Effect Rating Scale (SERS). Potentials predictors of treatment response were evaluated. RESULTS: From 62 patients, 47 completed the protocol. There was no significant change in the total score at the SNAP-IV (F (1,51.26) = 0.01; P = 0.91) and its subscales scores during the trial. Although no significant effect on the SERS total score (F (1,111.49) = 0.75; P = 0.39) was found, one adult patient with a previous cardiovascular condition presented a hemorrhagic cerebral vascular accident resulting in her obit. Overall, 46 (74.2%) patients reported to be satisfied. No factor assessed predicted dissatisfaction in univariated analyses. CONCLUSION: Results suggested that switching from MPH-IR to MPH-SODAS did not affect stabilization of ADHD symptoms in the majority of patients. MPH prescription in patients with previous cardiovascular conditions must be extremely careful. Further studies with long-acting MPH including larger samples and patients not responsive to MPH-IR are needed especially in countries outside the US.