Lifetime co-occurrence of DSM-III-R alcohol abuse and dependence with other psychiatric disorders in the National Comorbidity Survey.

OBJECTIVE: To study patterns of co-occurrence of lifetime DSM-III-R alcohol disorders in a household sample. METHODS: Data came from the National Comorbidity Survey (NCS), a nationally representative household survey. Diagnoses were based on a modified version of the Composite International Diagnostic Interview. RESULTS: Respondents with lifetime NCS/DSM-III-R alcohol abuse or dependence had a high probability of carrying at least 1 other lifetime NCS/DSM-III-R diagnosis. Retrospective reports have suggested that most lifetime co-occurring alcohol disorders begin at a later age than at least 1 other NCS/DSM-III-R disorder. Earlier disorders are generally stronger predictors of alcohol dependence than alcohol abuse and stronger among women than men. Lifetime co-occurrence is positively, but weakly, associated with the persistence of alcohol abuse among men and of alcohol dependence among both men and women. CONCLUSIONS: Caution is needed in interpreting the results due to the fact that diagnoses were made by nonclinicians and results are based on retrospective reports of the age at onset. Within the context of these limitations, though, these results show that alcohol abuse and dependence are often associated with other lifetime DSM-III-R disorders and suggest that, at least in recent cohorts, the alcohol use disorders are usually temporally secondary. Prospective data and data based on clinically confirmed diagnoses are needed to verify these findings.

Prevalence and correlates of drug use and dependence in the United States. Results from the National Comorbidity Survey.

OBJECTIVES: To analyze nationally representative data on the lifetime and 12-month prevalences of use of and dependence on illegal drugs (marijuana/hashish, cocaine/crack, heroin, hallucinogens), nonmedical prescription psychotropic drugs (sedatives, tranquilizers, stimulants, analgesics), and inhalants; and to examine data on the sociodemographic correlates of use and dependence. METHODS: The data come from the National Comorbidity Survey, a structured diagnostic interview administered to persons aged 15 to 54 years that generates reliable diagnoses according to the definitions and criteria of DSM-III-R. RESULTS: Of the respondents, 51.0% used one of the above drugs at some time in their lives, and 15.4% did so in the past 12 months. These estimates are similar to those obtained in the 1991 National Household Survey of Drug Abuse, where lifetime prevalence was 45.2% and 12-month prevalence was 16.7% among respondents in the age range 15 to 54 years. Of National Comorbidity Survey respondents, 7.5% (14.7% of lifetime users) were dependent at some time in their lives and 1.8% were dependent in the past 12 months. The prevalence estimate for lifetime dependence was reduced to 5.3% when calculated the percentage of respondents in the age range of 28 to 54 years who reported an onset of dependence as of 10 years earlier (ie, when they were 18 to 44 years old) was computed. This is similar to the Epidemiologic Catchment Area Study estimate of 5.1% among respondents in the age range 18 to 44 years, a comparison that matches the two studies on year of assessment, age of risk, and cohort. Males were significantly more likely to report both lifetime and 12-month use and dependence. Use and dependence were found to be more common in cohorts born after World War II than those born before the end of the war. The demographic predictors of lifetime use differed from the predictors of lifetime dependence among users, and these, in turn, differed from the predictors of recent dependence among people with a lifetime history of dependence. CONCLUSIONS: Drug use and dependence are highly prevalent in the general population. The fact that there are differences in the correlates of first use, dependence among users, and persistence of dependence means that future research aimed at pinpointing modifiable risk factors must be based on disaggregated analyses of separate stages of progression.

Optimal culture conditions for in vitro antigen-induced proliferation of rat lymph node cells.

Popliteal and inguinal lymph node cells (LNC) from rats immunized with ovalbumin (OA) in Freund's adjuvant, were cultured with OA for 4 days in a variety of serum-supplemented media. Incorporation of [3H]thymidine into [3H]DNA was assessed as an index of antigen-induced lymphoproliferation. Optimal conditions for proliferation were found to comprise culture in flat-bottomed vessels, in the presence of RPMI 1640 medium adjusted to rat osmolality (310 mosmoles/kg) containing 5% v/v fresh syngeneic rat serum plus 4 X 10(-4) M 2-mercaptoethanol.

Kindled seizures during a critical post-lesion period exert a lasting impact on behavioral recovery.

The present study was undertaken to assess the effects of amygdala kindling on behavioral recovery following unilateral frontal cortex damage in rats. Daily electrical stimulation of the amygdala began 48 h after lesion and continued until all animals had a single Stage 5 seizure. When amygdala kindled seizure activity ratable as Stage 0 occurred within the first 6 days after lesion, animals recovered from somatosensory asymmetries in approximately 3 weeks. In contrast, kindled animals that experienced Stage 1 seizure activity within the first 6 days after lesion failed to recover from somatosensory deficits in 4 months of testing. Differences in rate of recovery could not be accounted for by lesion size or placement. These data support the notion that not only is there a 'critical period' after brain damage during which the recovery process is vulnerable to seizure activity, but the type of kindled seizure that is experienced during that time ultimately determines how recovery is affected.

Prevalence and correlates of substance use disorders among older adolescents in Puerto Rico and the United States: a cross-cultural comparison.

Although there are substantial data on adolescent substance use, little systematic research has studied the prevalence of adolescent substance disorders in general populations, let alone cultural differences in disorder prevalence. In this paper we report the prevalence and correlates of alcohol and drug use and disorder among older adolescents on Puerto Rico (PR) and in the United States (US). Data come from an island-wide survey of the PR general residential population (15-18 year old subsample, unweighted N=922) fielded in 1997, and from the National Comorbidity Survey of the US household population (15-18 year old subsample, unweighted N=641), fielded in 1991. Both surveys used a similar standardized interview based on the Composite International Diagnostic Interview (CIDI) to generate DSM-IV diagnoses. Bivariate analyses and logistic regression were used. The major findings are: (1) US youth report higher rates of lifetime alcohol and drug use and substance-related disorder than PR youth; (2) the transition to abuse or dependence occurs for one-third of US drinkers, one-fifth of drinkers in PR, and about one-half of the drug users in both US and PR; (3) there are marked variations across sites in the types of symptoms substance users are likely to experience; (4) with the exception of family income, most correlates operate similarly in both sub-samples; and (5) the majority of both US and PR youth with a past year substance use disorder did not report any service utilization in the past year.

Drug abuse, methadone treatment, and health services use among injection drug users with AIDS.

This paper compares health care use across subgroups of injection drug users (IDUs) with AIDS, as defined by current drug abuse status and participation in methadone maintenance treatment (MMT), using surveillance-identified IDU status and health care claims data. Merged Medicaid and AIDS surveillance data were analyzed using ordinary least squares regression, simple logistic regression and multinomial logistic regression. Consistent MMT was more likely among women, Whites and older subjects. Monthly total expenditures and inpatient expenditures were significantly lower for IDUs in MMT than for IDUs with claims indicative of current drug abuse. Consistent participation in MMT was associated with a higher probability of antiretroviral use and, among antiretroviral users, more consistent use of antiretrovirals. Merged administrative data sets can be an important data source that illuminate the relationships among drug abuse, drug treatment, and HIV-related health care. For AIDS-infected IDUs, consistent MMT may lower barriers to receipt of appropriate HIV-related health care and reinforce adherence to medical recommendations.

Prevalence and demographic correlates of symptoms of last year dependence on alcohol, nicotine, marijuana and cocaine in the U.S. population.

The prevalence of last year use of alcohol, cigarettes, marijuana and cocaine in the U.S. population and conditional prevalence of a proxy measure of last year dependence among last year users of each drug class were assessed as a function of age, gender and ethnicity. Analyses were based on three aggregated waves (1991, 1992 and 1993) of the nationally representative samples of the general population aged > or = 12 interviewed in the National Household Surveys on Drug Abuse (n = 87915). An approximation of DSM-IV drug-specific last year dependence for each drug class was derived from self-reported symptoms of dependence, data on frequency and quantity of use and drug-related problems reported for the last year. Descriptive and multivariate analyses were conducted. The inclusion of cigarettes among the drugs, the large number of cases and the wide age range of respondents (> or = 12) enable us to make drug, age, gender and ethnic comparisons not otherwise possible in any other data set. The proxy measure of dependence, however, has limitations. The five major findings are that: (1) nicotine is the most addictive of the four drugs we examined; (2) among female last year users of alcohol and marijuana, adolescents are significantly more at risk for dependence than any other age group of women; (3) conditional prevalences of last year dependence on alcohol, marijuana and cocaine are higher among adolescent females than adolescent males but significantly different only for cocaine; (4) among adults, the rates of dependence are higher among males than among females for alcohol and marijuana, but lower for nicotine; and (5) among last year users, whites are more likely than any other ethnic group to be dependent on nicotine and blacks to be dependent on cocaine.

Antecedent tone presentation significantly delays rate of amygdala kindling.

External stimuli may contribute to seizure occurrence in at least two ways. First, the aberrant neuronal activity that precipitates a seizure could be elicited by certain external events; and second, external events could cue the organism to an impending seizure and result in a compensatory response that is, in effect, 'anti-convulsant'. While previous research has been aimed at addressing these issues, the results have been inconclusive. The present study was conducted to clarify and extend this prior work. Adult male Long-Evans hooded rats were chronically implanted with a kindling electrode and randomly assigned to one of two groups. The Tone group was presented with a 2-s auditory stimulus (Tone) beginning one second prior to and overlapping with the 1-s kindling stimulus. Animals in the No Tone group received only the kindling stimulus. Antecedent tone presentation significantly delayed the rate of amygdala kindling. The Tone group required significantly more stimulations to reach a Stage 5 seizure than did the No Tone group. The possibility of this phenomenon providing a means to study the mechanisms underlying anti-epileptogenesis is discussed.

The development of a short observation method for the study of the activity and contacts of old people in residential settings.

Data from a non-participant, 'event-sampling', direct observation study of 32 elderly persons in residential care were simplified and re-analysed, with the aim of developing a short, practical method of observation for use in research and training in residential care. A single, nominated hour's observation seemed to fit the data satisfactorily. This method, when applied to data from two newly observed contrasting samples, revealed the same important differences as had been found from a whole day's observation. A practical, short observation method thus emerged for use in research and training.

Beyond the rhetoric of zero tolerance: long-term solutions for at-risk youth.

Prevention of violence in schools must be accompanied by intervention across multiple contexts and the use of consistent but fair consequences that are implemented with children's positive development in mind.

Alveolar macrophages. VI. Regulation of alveolar macrophage-mediated suppression of lymphocyte proliferation by a putative T cell.

Alveolar macrophages (AM) from normal rats suppressed antigen- or mitogen-stimulated blastogenic responses in cultures of splenic or lymph node lymphocytes, high levels of suppression often being observed when added AM comprised as few 0.6% of the total cells in culture. The efficiency of AM-mediated suppression of spleen cell blastogenesis declined with the age of the spleen cell donors, was severely curtailed by pretreatment of donors with low levels of cyclophosphamide, and was depleted by adult thymectomy coupled with thoracic duct drainage. The suppressive activity of AM was most obvious at high cell density, was unaffected by the presence of indomethacin in the cultures, or by prior X-irradiation of the spleen cells. Fractionation of spleen cells by velocity sedimentation yielded cell populations of greatly varying sensitivities to AM-mediated suppression, from small splenocytes (sedimentation velocity 1.1-2.8 mm/h) which were almost totally refractory to AM-suppression when assayed in isolation from the remainder of the spleen cell population, to larger cells (sedimentation velocity greater than 3.,5 mm/h) exhibiting high levels of sensitivity. Fractionation of spleen cells by glass wool adherence indicated decreased sensitivity to AM-suppression in the effluent population. Examination of the suppressive activity of individual subpopulations of AM separated by velocity sedimentation indicated that the larger macrophages were the most active in vitro. Suppressive activity of this nature was not seen with unstimulated peritoneal macrophages, but was observed when 'activated' peritoneal exudate cells were tested. These data are discussed in terms of a two-cell model for suppression of blastogenesis, the ultimate effector cell being a macrophage, the activity of which is controlled by a long-lived, recirculating lymphocyte, which we have provisionally designated as a T lymphocyte.

Alveolar macrophages: functional heterogeneity within macrophage populations from rat lung.

Alveolar macrophages were obtained from the unstimulated lungs of rats by repeated endobronchial lavage and an interstitial macrophage population prepared by mincing the lungs subsequent to the lavage process. Considerable heterogeneity was observed within these macrophage populations with respect to cell size, surface morphology and cytochemistry. Functional studies, involving assessment of IgG-Fc receptor density/avidity and the expression of cytostatic activity in cultures of mitogen-stimulated lymphocytes, revealed comparable heterogeneity, and further indicated a considerably higher degree of apparent stimulation in the alveolar versus the interstitial macrophage population. Parallel assessment of the functional activity of blood monocytes, the immediate precursors of these latter macrophages, indicated a lower state of activation again. This suggests that the lung interstitium normally provides an intermediate environment between the blood and the alveolar spaces, wherein blood monocytes may undergo maturational changes before their efflux into the alveoli.