Reward discounting as a measure of impulsive behavior in a psychiatric outpatient population.

Impulsivity has been operationalized as a choice of an immediate smaller reward over a larger delayed or uncertain reward. This study examined a procedure that measures reward preference under these contingencies in psychiatric outpatients considered either at a high or low risk for engaging in impulsive behavior depending on their psychiatric diagnoses. The participants' rates of delay and uncertainty reward discounting were compared with their performances on a behavioral inhibition task and responses on a self-report personality impulsivity measure. The high-risk participants discounted delayed rewards more sharply and scored higher on the self-report impulsivity measure relative to the low-risk participants. Delay and uncertainty discounting were modestly correlated, but no other relationships were found between the other measures. Results from this study indicate that delay-discounting tasks may be sensitive to at least one form of impulsive behavior.

Buprenorphine dosing every 1, 2, or 3 days in opioid-dependent patients.

RATIONALE: Administration of double the maintenance dose of buprenorphine has been shown to permit every-other-day dosing. Whether longer periods between dosing can be achieved is unknown. OBJECTIVES: To examine whether triple the maintenance dose can be administered every 72 h without opioid withdrawal or intoxication. METHODS: Sixteen opioid-dependent outpatients each received three conditions (1) the maintenance dose of buprenorphine every 24 h, (2) double the maintenance dose every 48 h, and (3) triple the maintenance dose every 72 h under double-blind placebo-controlled conditions. Each conditions was imposed in a random sequence for 21-22 days. Self report and observer measures were taken at 24-h intervals. RESULTS: No significant differences were observed on measures of opioid agonist and withdrawal effects between the dosing conditions. However, averaging effects across conditions may obscure important within-condition effects. When conditions were analyzed by individual days within a condition, several significant effects were observed. For example, 24 h after administration of triple the maintenance dose, significant effects were observed in eight opioid agonist measures. Also, 72 h after administration of triple the maintenance dose, significant effects were observed on four measures of withdrawal. Neither adverse medical reactions nor excessive opioid intoxication were observed. CONCLUSIONS: These results suggest that buprenorphine may be administered safely every 72 h by tripling the maintenance dose, with only minimal withdrawal complaints. Importantly, this 72-h dosing may permit patients to attend clinic thrice weekly without the use of take-home doses.

Alternate-day buprenorphine dosing is preferred to daily dosing by opioid-dependent humans.

Alternate-day buprenorphine dosing was compared to daily dosing in opioid-dependent outpatients and choice of alternate-day versus daily dosing was assessed. Four dosing schedules were presented in random order under blind and open dosing conditions. Subjects received two exposures to each dosing schedule. During daily dosing, subjects received maintenance doses every 24 h. During blind alternate-day dosing, subjects received double maintenance doses every 48 h; placebo was interposed on intervening days. During open alternate-day dosing, subjects received twice their maintenance dose on Monday, Wednesday and Friday and maintenance doses on Sunday. After completing two exposures to each dosing schedule, subjects chose either daily or alternate-day schedules each week for 1 month. Study participation was contingent on daily attendance and opioid abstinence. Ten subjects were exposed to the four conditions once. Seven subjects repeated these conditions and participated in the choice phase. The effects of daily versus alternate-day dosing were not influenced by blind or open dosing conditions. Subjects' ratings of withdrawal, "sick" and sedation were lower during daily than during alternate-day dosing, but the difference between treatments was small. Nonetheless, subjects still chose alternate-day dosing on 96% of occasions, suggesting that the subject-rated differences between dosing schedules were not influential. These results extend prior findings to open-dosing conditions, and replicate the safety and acceptability of alternate-day buprenorphine treatment. Choice of alternate-day buprenorphine administration underscores the procedure's clinical utility and potential use as a positive reinforcer to enhance opioid treatment.

Preferences for clinic privileges, retail items and social activities in an outpatient buprenorphine treatment program.

This study evaluated preferences for various clinic privileges, retail items, and social activities for use in an outpatient opioid dependence treatment program. Fifty-three opioid-dependent patients who received treatment with buprenorphine for at least 30 days rank ordered 11 clinic privileges, 19 retail items, and 8 social activities from the most desirable (a rank of 1) to the least desirable (a rank equal to the number of items in that category). Additional questions determined preference for counseling frequency and dosing levels. The top three mean rankings for clinic privileges were $50 cash for opioid-negative urines (2.8), take-home doses of buprenorphine (3.6), and voucher points for opioid-negative urines (4.7). The top three mean rankings for retail items were restaurant gift certificates (4.1), movie passes (4.9), and videotape movie and player rentals (6.8). The top three mean rankings for social activities were movies (2.4), barbecues (3.8), and hiking trips (4.3). There was no preference reported for increases or decreases in counseling frequency. Seventy-four percent of subjects preferred to increase their buprenorphine dose by an average of 60.84% independent of their present dose. Consistent with previous findings from methadone treatment, cash payments for opioid-negative urines and take-home medication were the highest ranked clinic privileges. These results suggest that various retail items and social activities may also be useful for reinforcing positive treatment outcomes during outpatient opioid treatment.