Buprenorphine/naloxone versus methadone in opioid dependence: a longitudinal survey.

BACKGROUND AND OBJECTIVES: Buprenorphine and methadone are widely used for the treatment of opioid dependence, but their diversion and/or misuse are frequent. In principle, buprenorphine/naloxone combination therapy should be associated with a lower frequency of drug abuse/misuse than methadone. This study assessed the efficacy of the substitution of buprenorphine treatment with the buprenorphine/naloxone combination in opioid-dependent patients. MATERIAL AND METHODS: 3812 drug-addicted outpatients selected from 10 Italian Public Services for Addiction (Ser.T.) centres in Naples (Italy) were enrolled: 3105 (81.5%) were treated with methadone and 707 (18.5%) with buprenorphine. The buprenorphine treatment was switched to buprenorphine/naloxone (4:1), and the patients were followed for about 1 year. The number of subjects still on treatment after 1 year, their status according to social, educational and toxicologic (assessed by a urine toxicology test) parameters were assessed. RESULTS: 1 year after the therapy switch, the number of patients still on treatment was similarly reduced with methadone (2883; -7.5%) and buprenorphine/naloxone (632; -10.6%; p=0.369). However, in patients treated with buprenorphine/naloxone, a significant improvement was reported in social life status (63% versus 39% of the buprenorphine/naloxone and methadone treated subjects, respectively, were married/cohabiting p<0.001), in the educational level (43% of buprenorphine/naloxone treated versus 32% of the methadone treated subjects obtained at least a high school certificate, p<0.001) and in the toxicological conditions (53% of buprenorphine/naloxone treated subject versus 30% of methadone treated individuals had opioid- and cocaine- negative urine tests, p<0.001). DISCUSSION: These preliminary data suggest that buprenorphine/naloxone treatment of opioid dependence reduces the percentage of treated subjects similarly to methadone, and is associated with an improvement in social life, educational and toxicological conditions, compared with methadone treatment. However, we cannot exclude a selection bias, i.e. patients who were more likely to stabilize their opiate dependence switched to buprenorphine/naloxone.

Frequency of a mutated CCR-5 allele (delta32) among Italian healthy donors and individuals at risk of parenteral HIV infection.

The aim of this study was to assess the frequency of a truncated allele of the CCR-5 gene (delta32) in Italy, and address its possible role in parenteral HIV transmission, as well as its influence in HIV-associated disease progression. In 371 unrelated seronegative healthy blood donors the delta32 allele frequency was 0.047; this figure was significantly different from those reported in northern America and northern Europe populations. However, delta32 allele frequency in healthy individuals did not differ significantly from that found in 54 seronegative drug users (0.065), 98 seronegative hemophiliacs (0.051), and 81 seropositive hemophiliacs (0.049). Although in seropositive hemophiliacs the wt/delta32 heterozygous genotype was associated with a trend to a slower decline in CD4+ cell counts, its presence did not seem to influence disease progression, as comparable delta32 allele frequency frequencies were found among progressing (0.042) and nonprogressing (0.111) patients. These data do not seem to support a protective role of the delta32 allele in preventing HIV infection through the parenteral route, or in influencing the natural history of the disease in this particular risk category, although the delta32 heterozygous state was associated with lower plasma viremia levels. On the other hand, the finding of non-syncytium-inducing HIV strains in the majority of delta32 heterozygous seropositive patients suggests that its presence could not be a major factor in driving a switch toward more cytopathic, T-tropic HIV strains through selective pressure in coreceptor usage.

Early neuropsychological impairment in HIV-seropositive intravenous drug users: evidence from the Italian Multicentre Neuropsychological HIV Study.

The aim of the Italian Multicentre Neuropsychological HIV Study is to assess the prevalence and natural history of cognitive deficit in intravenous drug users (i.v.DUs) during the asymptomatic phase of HIV infection. The study is currently being conducted in four centres (Napoli, Benevento, Verona and Pavia) whose catchment areas are characterized by different levels of prevalence of HIV infection. Cognitive evaluation is being performed by means of a standardized neuropsychological test battery. A total of 251 subjects (167 males and 84 females) have been recruited in the cross-sectional phase of the study, including 75 asymptomatic HIV-seropositive i.v.DUs (HIV+/i.v.DUs), 97 HIV-seronegative i.v.DUs (HIV-/i.v.DUs) and 79 non-i.v.DU seronegative controls matched to i.v.DUs with regard to sex, age and educational level. The prevalence of global cognitive impairment (performance at least 1.5 standard deviations worse than the average of the control group, on at least two out of five tests) was significantly higher in HIV+/i.v.DUs than in either HIV-/i.v.DUs (22.7% vs. 8.2%; P < 0.01) or healthy controls (22.7% vs. 2.5%; P < 0.001). The difference between HIV-/i.v.DUs and healthy controls was not statistically significant (8.2% vs. 2.5%; P = 0.19). The results of this study lend further support to the 'cerebral reserve' model. The cerebral reserve could indeed be reduced in i.v.DUs as a consequence of chronic exposure to the substance of abuse, so that these subjects become more vulnerable to direct and indirect neurotoxic effects of HIV.

Incidence rate and risk factors for HCV seroconversion among injecting drug users in an area with low HIV seroprevalence.

We conducted a study on injecting drug users attending one of 3 drug treatment centres in Naples, to estimate HIV and hepatitis C virus (HCV) incidence rates and to identify risk factors for seroconversion. Incidence rates were estimated using as denominator the person-time of follow-up of participants who were negative for both HIV and HCV at enrollment and who were retested within 6-12 months. Information on risk factors was collected using a standardized questionnaire. A nested case-control analysis was performed comparing seroconverters with persistently HCV-negative individuals. None of the initially non-infected participants seroconverted for HIV, while the incidence rate for HCV infection was approximately 29 per 100 person-years. Analysis of risk factors showed that age > 28 years and injecting use of cocaine were associated with HCV seroconversion. The protective role of methadone treatment was also marginally significant. Our findings suggest that HCV infection may represent an important public health problem in areas with low HIV circulation. The identification of specific risk factors for HCV infection is needed to plan effective prevention strategies.

Atopy and coeliac disease: bias or true relation?

Several reports have suggested a relationship between atopy and coeliac disease and atopy has also been linked to the pathogenesis of the mucosal damage. Conclusive epidemiological evidence of the relationship has not been satisfactorily established. The case-control study reported here was undertaken to test the hypothesis that coeliac disease is linked to atopy. Eighty-two coeliac disease cases and a group of 180 age matched controls and all their first degree relatives were investigated for atopy. Siblings of cases reported an increased prevalence of food intolerance, compared to siblings of controls. No increase in asthma, eczema, rhinitis, conjunctivitis, cow's milk protein allergy (CMPA) were detected in relatives of cases, compared to those of controls. When each index case and each control were investigated no increased prevalence of atopic conditions was found. Skin prick testing to major allergens was positive in a similar proportion of cases and controls. Serum total IgE of a random sample of cases and controls showed no difference in mean values. This study supports the null hypothesis: there is no difference in the prevalence of atopy in cases affected by coeliac disease and their relatives, compared to controls and their relatives. The sources of possible bias in previous reports are discussed.