A Prospective Open-Label Pilot Study of Transcranial Direct Current Stimulation in High-Functioning Autistic Patients with a Dysexecutive Syndrome.

BACKGROUND: Executive functions (EF) are often impaired in autism spectrum disorder (ASD). Such dysfunctions are associated with anxiety, depression, and a lack of autonomy. Transcranial direct current stimulation (tDCS) has been shown to enhance EF in healthy adults and clinical populations and to improve working memory - a component of the EF - in adults with high-functioning ASD (HF-ASD). We hypothesized that tDCS could improve the EF of HF-ASD patients. Such enhancement could improve their adaptive behaviors. METHOD: Eight patients with HF-ASD received 10 consecutive cathodal tDCS sessions (2 mA) over the left dorsolateral prefrontal cortex (F3) for 15 min each in an open trial. EF (with the Stroop test, Trail Making Test [TMT] A and B, Modified Wisconsin Card Sorting Test [mWCST], and Verbal Fluency Test) and behavioral dysexecutive syndrome (with the Behavioral Dysexecutive Syndrome Inventory and the Repetitive and Restricted Behaviour scale) were assessed before and 10 days after treatment. RESULTS: This study showed significant improvement in initiation (TMT-A time: p = 0.018) and cognitive flexibility (TMT-B time: p = 0.009; letter Verbal Fluency Test: p = 0.017; mWCST total errors: p = 0.028) after tDCS. Regarding behavior, the hypoactivity of the patients improved, as well as their repetitive and restrictive behaviors. In addition, this noninvasive neurostimulation technique was well tolerated. CONCLUSIONS: Flexibility and initiation are the most impaired EF in autism. These are promising results which justify a randomized and placebo-controlled study in a wider population. If these results were confirmed by a randomized controlled trial, tDCS could be an easy and well-tolerated adjunctive treatment aiming to improve the quality of life and the autonomy of ASD patients.

Interest of adjusting urine cannabinoids to creatinine level to monitor cannabis cessation therapy in heavy smokers with psychiatric disorders.

Up to 25% of hospitalized patients in a psychiatric department exhibit troubles linked to cannabis use. Weaning patients with psychiatric disorders off drugs of abuse requires specific care to improve their clinical outcome. The present study aims to develop a predictive model of urinary excretion of creatinine-normalized cannabinoids (UCNC ) and to determine UCNC thresholds corresponding to the widely used cut-offs of 20 ng/mL and 50 ng/mL for cannabinoids. One hundred thirty-two patients with 452 urine samples were included between 2013 and 2017. Urinary cannabinoids and UCNC elimination curves were computed for each patient. Using a mono-exponential mixed effect model with 88 samples from 26 subjects exhibiting at least 3 decreasing UCNC in a row, the average calculated elimination rate constant was 0.0108 ± 0.0026 h-1 , corresponding to a mean elimination half-life of 64 ± 12 hours. The use of UCNC is of particular interest because of a high inter- and intra-individual variability of urinary creatinine concentration (from 0.06 to 3.81 mg/mL). Moreover, UCNC allows for the detection of diluted or concentrated urine specimens that may lead to false positive (FP) or false negative (FN) results. Receiver operator characteristic (ROC) curves were used to assess UCNC thresholds of 32.4 and 124.7 ng/mg that provide a strong discrimination between positive and negative samples for cannabinoids cut-offs of 20 and 50 ng/mL respectively. The developed model and the defined UCNC thresholds allowed for the accurate prediction of the time needed to reach a negative UCNC result that could be used by clinicians to optimize clinical care.