High Concomitant Misuse of Fentanyl in Subjects on Opioid Maintenance Treatment.

BACKGROUND: Concomitant opioid misuse is an increasing problem in opioid maintenance treatment as it interferes with treatment success. OBJECTIVE: Therefore, the rates of concomitant fentanyl misuse in opioid maintained patients were investigated. METHODS: We conducted a cross-sectional study which consisted in collecting data via urine samples and questionnaires in Germany. Urine samples of patients on opioid maintenance treatment were gathered and fentanyl concentrations were measured from 2008 to 2012. An anonymous questionnaire provided data on the consumption of fentanyl as concomitant drug. Data were analyzed with descriptive statistics and group differences were calculated using the Chi-Square test. RESULTS: Among the total sample (urine probes of 960 patients), 6.8% opioid maintained patients had positive urine samples for fentanyl and 37.9% reported concomitant fentanyl misuse (401 of these patients filled out the questionnaire). A significant age-related association of concomitant fentanyl misuse was identified in the urine analyses (χ2 = 7.489; p = .024) and also in the questionnaire data (χ2 = 11.899, p = .003), indicating that young age increased the probability of fentanyl consumption. Patients receiving methadone had the highest rates of concomitant fentanyl misuse with 18.4% according to urine analysis. In addition, the results show that patients who are on diamorphine are significantly less likely to misuse fentanyl. CONCLUSIONS: Fentanyl is a frequently used concomitant drug. Especially young patients and patients taking methadone are at high risk. Because of the life-threatening consequences of fentanyl overdose, patients taking fentanyl should be intensively medically surveilled.

Polymodal Transient Receptor Potential Vanilloid (TRPV) Ion Channels in Chondrogenic Cells.

Mature and developing chondrocytes exist in a microenvironment where mechanical load, changes of temperature, osmolarity and acidic pH may influence cellular metabolism. Polymodal Transient Receptor Potential Vanilloid (TRPV) receptors are environmental sensors mediating responses through activation of linked intracellular signalling pathways. In chondrogenic high density cultures established from limb buds of chicken and mouse embryos, we identified TRPV1, TRPV2, TRPV3, TRPV4 and TRPV6 mRNA expression with RT-PCR. In both cultures, a switch in the expression pattern of TRPVs was observed during cartilage formation. The inhibition of TRPVs with the non-selective calcium channel blocker ruthenium red diminished chondrogenesis and caused significant inhibition of proliferation. Incubating cell cultures at 41 °C elevated the expression of TRPV1, and increased cartilage matrix production. When chondrogenic cells were exposed to mechanical load at the time of their differentiation into matrix producing chondrocytes, we detected increased mRNA levels of TRPV3. Our results demonstrate that developing chondrocytes express a full palette of TRPV channels and the switch in the expression pattern suggests differentiation stage-dependent roles of TRPVs during cartilage formation. As TRPV1 and TRPV3 expression was altered by thermal and mechanical stimuli, respectively, these are candidate channels that contribute to the transduction of environmental stimuli in chondrogenic cells.

Sleeping Patterns in Patients with Opioid Use Disorder: Effects of Opioid Maintenance Treatment and Detoxification.

The aim of the study was to explore whether abstinent patients on recent opioid detoxification or on opioid maintenance treatment suffer from sleeping problems. 199 patients on opioid maintenance treatment (methadone, diacetylmorphine and buprenorphine) or recent opioid detoxification were included in this exploratory cross-sectional study. We used the Pittsburgh Sleep Quality Index (PSQI) and the Regensburger Insomnia Scale (RIS) in order to assess potential sleeping problems. There was a significant effect of the condition "opioid maintenance" or "recent opioid detoxification" on the total score of PSQI and RIS. All opioid maintenance drugs used by the study population were associated with more sleeping problems compared to the detoxification group when calculated with RIS values. Recently abstinent patients (opioid detoxification) displayed significantly fewer sleep disturbances than opioid-maintained patients. Since sleeping problems can seriously impair treatment success and quality of life, screening for sleep disturbances and their subsequent treatment is of pronounced relevance.