Neurobiological Effects of Transcranial Direct Current Stimulation Treatment in Alcohol Use Disorder

BDNF levels will be evaluated by collecting a venous blood sample. BDNF is a member of the nerve growth factor (NGF) family of neurotrophic growth factors. Low levels of peripheral BDNF and NGF have been reported in mood disorders and other psychopathological conditions with normalization after antidepressant treatment or mood stabilization. The increase in serum levels of BDNF seems to reflect the concomitant activation of BDNF synthesis that accompanies the neuronal remodeling triggered by the suspension of alcohol intake and suggests that the synthesis of BDNF may have a role in the long-term maintenance of alcohol abstention. BDNF measurements will be calculated in pg/ml

Pro-BDNF is the precursor of BDNF and it acts as a repository of mature BDNF and acts itself by inducing neuronal thinning. Pro-BDNF levels will be evaluated by collecting a venous blood sample. Pro-BDNF measurements will be calculated in ng/ml.

Pro-BDNF/BDNF ratio, seems to be a more specific measurement of the early changes in the metabolism of BDNF. Its level seems to correlate to more or less a neurotrophic and neuroprotective action of BDNF.

The TLFB is a calendar-based interview method in which the individual retrospectively identifies the days when alcohol was assumed, and the number of standard drinks consumed on those days. // Alcohol consumption will be assessed using the TimeLine Follow Back (TLFB). TLFB is an interview-based assessment. Using a calendar, participants are guided through the process of recalling and reporting daily alcohol consumption. TLFB provides measures of alcohol consumption per week, alcohol consuming days per week, heavy alcohol consuming days per week.

Alcohol craving intensity will be assessed using a visual analog scale (VAS). Participants sign subjective feelings of craving on a 10 cm line marked from zero (null) to 10 (the most intense).

Alcohol craving will be assessed using the Brief Substance Craving Scale (BSCS). The BSCS is a 16 item, self-report instrument assesses craving for substances of abuse over a 24 hour period.

Alcohol consumption will be evaluated by breathalyzer. Breathalyzer measures breath alcohol concentration (BrAC) levels; the BrAC-data was interpreted as blood alcohol content (BAC). Semi-quantitative analyses are performed. The breathalyzer can differentiate five levels: negative (0 - 0.07 gr / L), low (0.07 - 0.3 gr / L), warn (0.31 - 0.5 gr / L), fall (0.51 - 0.8 gr / L), fall + (> 0.8 gr / L)

Alcohol craving subtype will be assessed using the Craving Typology Questionnaire (CTQ). It is a self-report questionnaire measuring three supposedly independent typologies of alcohol craving: relief, obsessive and reward craving.

The MADRS is a 10-item scale that evaluates the core symptoms and cognitive features of clinical depression. Each MADRS item is rated on a 0 to 6 scale. The MADRS Total score ranges from 0 (min) to 60 (max). Higher MADRS scores indicate higher levels of depressive symptoms.

Substances consumption will be evaluated by Urine Drug Screen (UDS). Urine Drug Screen is a test to evaluate the presence of substances of abuse in urine samples. Quantitative analyses are not performed. Test may be positive or negative for the presence of substances of abuse.

Frontal Assessment Battery (FAB) is a short neuropsychological tool aimed at assessing executive functions. The FAB consists of six subtests, each exploring functions related to the frontal lobes: conceptualization (by means of a similarities task), mental flexibility (by means of a phonological fluency task), motor programming (by means of Luria's motor series), sensitivity to interference (by means of a conflicting instruction task), inhibitory control (by means of a go-no-go task), and environmental autonomy (by means of evaluation of prehension behavior). Each subtest score may range from 0 (min) to 3 (max); total score is from 0 (min) to 18 (max). Higher scores indicate better performance.

The HAM-A is a 14-item scale that assesses anxiety symptoms of anxiety such as "anxious mood", "tension" or "fears". Each item is scored on a 5-point scale, ranging from 0 (not present) to 4 (severe). Sum the scores from all 14 parameters gives the HAM-A Total Score which may range from 0 (min) to 56 (max).

The HAM-D is a 21-item scale that measures the severity of depressive symptoms and additional clinical information (diurnal variation, depersonalization/derealization, paranoid symptoms, and obsessive-compulsive symptoms). The severity of depression is divided into 4 categories as follows: 0-7 is considered as normal patients, 8-16 suggesting mild depression, 17-23 suggesting moderate depression and scores over 24 indicating severe depression. The total HDRS score ranged from 0 to a maximum of 52 points.

The Barratt Impulsiveness Scale 11th version (BIS-11) is a 30-item scale that assesses impulsivity. The BIS-11 was developed to specifically measure impulsiveness, in contrast to other "action-oriented" traits such as sensation-seeking, extraversion, and risk taking. The total BIS-11 score ranged from 30 to a maximum of 120 points. Higher scale scores indicate higher levels of impulsiveness.

The TAS-20 is a self-report scale that assesses alexithymia. It is comprised of 20 items assessing three dimensions of alexithymia, i.e., Difficulty Identifying Feelings (DIF), Difficulty Describing Feelings (DDF), and Externally Oriented Thinking (EOT). Each of the twenty items is rated on a 5-point Likert scale. Increasing scores indicate higher degrees of alexithymia. The TAS-20 uses cutoff scoring: equal to or less than 51 = non-alexithymia, equal to or greater than 61 = alexithymia. Scores of 52 to 60 = possible alexithymia.

The BDI-II is a 21-item self-report measure of depressive symptoms. Each of the 21 items corresponding to a symptom of depression is summed to give a single score for the Beck Depression Inventory-II (BDI-II). There is a four-point scale for each item ranging from 0 to 3. On two items (16 and 18) there are seven options to indicate either an increase or decrease of appetite and sleep. Cut-off score guidelines for the BDI-II are given with the recommendation that thresholds be adjusted based on the characteristics of the sample, and the purpose for use of the BDI-II. Total score of 0-13 is considered minimal range, 14-19 is mild, 20-28 is moderate, and 29-63 is severe.

The SOGS is a 20-item instrument to screen for probable pathological gambling. A cut score of 5 or more is typically used to indicate that the individual is a probable pathological gambler.

The LAPS is a 16-item questionnaire to assess negative affect, positive affect, and hedonic tone. The 16-item scale comprises 3 subscales (negative affect, positive affect, hedonic tone) and 4 independent items (cognitive functioning, overall functioning, my life is meaningful, I feel happy). Patients rate their positive and negative moods, and hedonic tone from 0 to 10, where 0 is not at all, 1-3 are scores for a little bit, 4-6 are scores for moderately, 7-9 are scores for quite a bit and 10 represents very much.

The G-SAS is a 12-item self-rated scale designed to assess gambling symptom severity and change during treatment. Each 12-item scale has a score ranging from 0 - 4 (adjective anchors for 0 and 4 vary for each item). All items ask for an average symptom based on the past 7 days. Total score ranges from 0 - 48: extreme = 41 - 48, severe = 31 - 40, moderate = 21 - 30, mild = 8 - 20.

The Y-MRS is a 11-item scale to assess manic symptoms based on the patient's subjective report of his or her clinical condition over the previous 48hours. Additional information is based upon clinical observations made during the clinical interview. YMRS cut-off values were minimal (13), mild (20), moderate (26), and severe (38) manic symptoms.

The BPRS-E is a 24-item scale for assessing type, severity and change over time of 24 psychiatric symptoms. The presence and severity of psychiatric symptoms were rated on a Likert scale ranging from 1 (not present) to 7 (extremely severe). Thus, possible scores vary from 24 to 168 with lower scores indicating less severe psychopathology.

The TES is a short tool aimed at assessing any possible discomfort during the electrical stimulation (e.g., itching, pain or burning), the duration and the degree of intensity discomfort.

A) The SOCRATES 8A is a 19-items scale that measures participants general level of motivation. SOCRATES 8A assess strengths and needs in the areas of treatment readiness, motivation of problem drinkers and drug users for change and to enter treatment. It provides scores on three subscales- Recognition, Ambivalence and Taking steps.

The IGT is a computer-administered neuro-psychological test to evaluate decision-making abilities. It consists of 100 card selections from four decks of cards divided into five distinct blocks of 20 trials each to examine participant's learning curve. A total score for the IGT is calculated by subtracting the total number of selections from the bad decks from the total number of selections from the good deck. A positive total score indicates advantageous decision-making, whereas a negative total score indicates disadvantageous decision-making.

The SCWT evaluates attention, information processing speed, selective attention, cognitive flexibility and the ability to inhibit cognitive interference of simultaneous stimulus. The SCWT evaluates the reaction times to non-ambiguous stimuli and to ambiguous stimuli.