Suspected causal association between cocaine use and occurrence of panic.

AIM: To estimate a suspected causal association between cocaine use and the occurrence of panic. METHODS: Data are from an epidemiologic sample of school-attending youths enrolled in primary school who were traced, rerecruited, and assessed via standardized interviews in young adulthood during 2000-2002. A total of 1,692 young adults comprised the analysis sample. Occurrences of panic and cocaine use were assessed in young adulthood, via standardized item sets from the Diagnostic Interview Schedule. A brief assessment of panic experiences had also been made when the youths were in early adolescence. RESULTS: With statistical adjustment for important covariates, we found a modestly excess occurrence of panic attack-like experiences among those who had used cocaine at least once, relative to occurrence among young people who never had used cocaine (estimated odds ratio, OR = 1.9; p = .014 before exclusion of 288 with early onset panic attack-like experiences; p = .005 after this exclusion). DISCUSSION: The main finding of this study was an association linking cocaine use and panic attack-like experiences, which was more modest than was observed in study samples that included older adults.

Tobacco use among high school students in Buenos Aires, Argentina.

OBJECTIVES: This study assessed the prevalence and correlates of tobacco use among high school students in Buenos Aires, Argentina. METHODS: Anonymous, self-administered questionnaires were given to 3909 8th and 11th graders in a stratified random sample of 49 public and private schools. The instrument included items from American surveys, translated and validated among Argentinean teens. Multiple logistic regression analysis was used to estimate possible effects on smoking behavior of environment, students' personal characteristics, and their knowledge, beliefs, and attitudes regarding smoking. RESULTS: Of 8th and 11th graders, 20% and 43%, respectively, were classified as current smokers. Overall, 29% of males and 32% of females were current smokers. Students attending public schools were more likely to smoke than those in private schools (P < .05). Current smoking was associated with having a best friend who smokes, reporting that more than 50% of friends of the same sex smoke, having positive attitudes and beliefs toward smoking, and having a positive intention to smoke within the next year (all P < .001). CONCLUSIONS: Over 20% of the 8th graders in our sample were current smokers; prevention efforts must therefore start early.

Clusters of drug involvement in Panama: results from Panama's 1996 National Youth Survey.

This report is based on the first epidemiological investigation of clustering of tobacco, alcohol, inhalant, and other drug involvement within individual schools using data from Panama's 1996 National Youth Survey on Alcohol and Drug Use. Clustering was estimated with the Alternating Logistic Regression method. Adjusted estimates of pair-wise cross-product ratios (PWCPR), a measure of clustering, show modest clustering (i.e. PWCPR>1.0) at the school level for tobacco smoking (PWCPR=1.41; 95% confidence interval, CI=1.22-1.64), alcohol consumption (PWCPR=1.33; 95% CI=1.22-1.45), use of inhalants, (PWCPR=1.35; 95% CI=1.07-1.69), and other drug use (PWCPR=1.38; 95% CI=1.14-1.68). These findings provide preliminary evidence that the odds of drug use among school-attending youths increase when another youth in the same school uses drugs, and suggest a new line of research on within-school diffusion that should include the identification of school-level factors that contribute to student drug use.

First opportunities to try drugs and the transition to first drug use: evidence from a national school survey in Panama.

In recent evidence from the United States, there generally are no male-female differences in the probability of drug use among persons who report an opportunity to try the drugs. This is an important observation that might help us understand male-female differences in later drug use and dependence, but the observation needs to be replicated elsewhere. We begin this replication process using data from a 1996 national school survey of drug involvement among 6,477 students age 12-18 in Panama. We first examine the occurrence of an opportunity to use drugs by grade. We then follow these analyses with an examination of male-female differences in drug opportunity patterns. We found opportunities to use drugs and actual drug use to be greater at higher grade levels. Also, we found the probability of making a transition to use, given an opportunity, to be more likely among upper-grade students. Consistent with results observed in the United States, we found males in Panama to be more likely to have an opportunity to use marijuana, crack-cocaine, and other forms of cocaine, but not more likely than females to make a transition into drug use once an opportunity had occurred to try each drug. These findings are discussed in relation to the epidemiology and prevention of drug use in Panama and elsewhere, and future research on male-female differences in drug involvement.

Estimated occurrence of tobacco, alcohol, and other drug use among 12- to 18-year-old students in Panama: results of Panama's 1996 National Youth Survey on Alcohol and Drug Use.

This report provides the first epidemiological evidence on tobacco, alcohol, and other drug use among school students in Panama, using data from a student survey completed in 1996. Specifically, we examine sex, age, grade level, type of school, and urban-rural variations in the occurrence of tobacco, alcohol, and other drug use. Estimates of lifetime prevalence and past-year use of these products were obtained using data from Panama's 1996 National Youth Survey on Alcohol and Drug Use (n = 6,477). To account for the multistage sampling design of the survey, all estimates and respective standard errors are derived by the Taylor series approximation method using Epi Info 6.0 CSAMPLE software. In general, more males, more older students, and more students in higher grades have used licit and illicit drugs, even though male-female differences tend to be small. Public-private school differences and urban-rural trends vary depending on the drug. The findings of this study are discussed in relation to the epidemiology and prevention of drug use in Panama. Based on these data, we seek to provide information to be used by the Government of Panama in its planning for prevention programs directed toward students in Panamanian schools.

Use of the inhalant lança by Brazilian medical students.

In a recent epidemiological survey of more than 700 Brazilian medical students, we found new evidence on a previously reported pattern of the "lança perfume" inhalant drug use. With multiple logistic regression used to hold constant an array of suspected correlates, we found a moderately strong association between the use of marijuana and the use of lança (adjusted odds ratio, OR = 5.6; p < .01). We also found that lança is almost never used by students who have never consumed alcoholic beverages. This pattern of associations can be used to guide the planning of programs to reduce the occurrence of illicit use of pharmaceutical compounds by medical students in Brazil.

Degree of acculturation and the risk of crack cocaine smoking among Hispanic Americans.

Epidemiologic data from three national surveys conducted in 1988, 1990, and 1991 were used to investigate the association between acculturation and use of crack cocaine among Hispanic Americans living in the United States. Poststratification and conditional logistic regression were used to hold constant shared aspects of neighborhood environment, age, sex, and education. The analyses showed a strong inverse relationship between degree of acculturation and crack smoking among Mexican Americans (relative odds = 0.12, 95% confidence interval = 0.04, 0.34) but not among other Hispanics in the study population. This observed variation within the US Hispanic American population deserves special attention in future research.

Drug abuse and illicit drug use in Puerto Rico.

OBJECTIVES: Based on an epidemiologic field survey of community households in Puerto Rico, this study estimates the frequency of illicit drug use and clinically defined drug abuse and/or dependence syndromes. Results are compared with those from surveys on the United States mainland. Suspected risk factors are studied as well, with a special focus on childhood misbehavior. METHODS: Trained lay interviewers administered a Spanish Diagnostic Interview Schedule to 912 respondents aged 17 to 68 years who were selected by multistage probability sampling of island households. RESULTS: An estimated 8.2% of the population had a history of illicit drug use and 1.2% qualified for a standardized lifetime diagnosis of drug abuse, dependence, or both. An estimated 18.4% of the male drug users and 7.7% of the female drug users met criteria for drug abuse and/or dependence. A history of drug use was related to the diagnoses of alcohol abuse and/or dependence and antisocial personality, but few persons who had used illicit drugs at least once in their lifetime reported a history of receiving treatment for alcohol, drug, or mental health problems. CONCLUSIONS: The data were consistent with a suspected association between level of childhood misbehavior and occurrence of illicit drug use, even after statistical control for potentially confounding variables.

Human IgE responses to Schistosoma mansoni and resistance to reinfection

Schistosoma mansoni infected Kenyan patients were treated and the intensities of their reinfections were followed over the next two years. in addition, their pre- and six month post-treatment serum levels of IgG1-4, IgM, and IgE, specific for schistosoma, egg and adult worm, were measured in ELISA. No reinfection took place before six months post-treatment. Reinfection intensities varied with age; the younger children becoming reinfected at significantly higher intensities than older individuals. When antibody and reinfection levels were compared, only the six month post-treatment IgE response against adult worm correlated negatively with intensities of reinfection and, therefore, was predictive of resistance or immunity to reinfection. IgE and IgG specific Western Blots were carried out. The adult worm antigens recognized by IgE were restricted compared with the IgG responses of the same patients, although no individual antigen was uniquely recognized by the IgE isotype. A dominant 22 kDa antigen was recognized by most but not all high IgE responders. Patients with IgE responses against this antigen suffered significantly lower subsequent levels of reinfection, compared with non-responders. A monospecific rabbit antiserum against the 22KDa adult worm antigen showed that this antigen is specifically located in the tegument of the adult worm and of 'lung' and 'liver' stage schistosomula, but is absent from the early 'skin' schistosomula. It is possible that this antigen is a target for human IgE mediated immune effector mechanisms active against the post skin stage schistosomula and that this is boosted by the death of adult worms

Human antibody responses to Schistosoma mansoni: does antigen directed, isotype restriction result in the production of blocking antibodies?

After treatment young Kenyan schoolchildren are highly susceptible to reinfection with Schistosoma mansoni. Older children and adults are resistant to reinfection. There is no evidence that this age related resistance is due to a slow development of protective immunological mechanisms, rather, it appears that young children are susceptible because of the presence of blocking antibodies which decline with age, thus allowing the expression of protective responses. Correlations between antibody responses to different stages of the parasite life-cycle suggest that, in young children, antigen directed, isotype restriction of the response against cross-reactive polysaccharide egg antigens results in an ineffectual, or even blocking antibody response to the schistosomulum.