Despite the value of 12-step meetings, few studies have examined factors associated with attendance among those living with HIV/AIDS, such as the impact of HIV disease severity and demographics.
This study examines predisposing characteristics, enabling resources and need on attendance at Alcoholic Anonymous (AA) and Narcotics Anonymous (NA) meetings among those living with HIV/AIDS and alcohol problems.
Secondary analysis of prospective data from the HIV-Longitudinal Interrelationships of Viruses and Ethanol study, a cohort of 400 adults living with HIV/AIDS and alcohol problems. Factors associated with AA/NA attendance were identified using the Anderson model for vulnerable populations. Generalized estimating equation logistic regression models were fit to identify factors associated with self-reported AA/NA attendance.
At study entry, subjects were 75% male, 12% met diagnostic criteria for alcohol dependence, 43% had drug dependence and 56% reported attending one or more AA/NA meetings (past six months). In the adjusted model, female gender negatively associated with attendance, as were social support systems that use alcohol and/or drugs, while presence of HCV antibody, drug dependence diagnosis, and homelessness associated with higher odds of attendance.
Non-substance abuse related barriers to AA/NA group attendance exist for those living with HIV/AIDS, including females and social support systems that use alcohol and/or drugs. Positive associations of homelessness, HCV infection and current drug dependence were identified. These findings provide implications for policy makers and treatment professionals who wish to encourage attendance at 12-step meetings for those living with HIV/AIDS and alcohol or other substance use problems.
HIV-infection; alcohol addiction disorder; substance-related disorders; 12 step groups; HIV/AIDS
Despite the vast literature examining disparities in medical care, little is known about racial/ethnic and mental health disparities in sexual health care. The objective of this study was to assess disparities in safe sex counseling and resultant behavior among a patient population at risk of negative sexual health outcomes.
We conducted a cross-sectional analysis among a sample of substance dependent men and women in a metropolitan area in the United States. Multiple logistic regression models were used to explore the relationship between race/ethnicity (non-Hispanic black; Hispanic; non-Hispanic white) and three indicators of mental illness (moderately severe to severe depression; any manic episodes; ≥3 psychotic symptoms) with two self-reported outcomes: receipt of safe sex counseling from a primary care physician and having practiced safer sex because of counseling.
Among 275 substance-dependent adults, approximately 71% (195/275) reported ever being counseled by their regular doctor about safe sex. Among these 195 subjects, 76% (149/195) reported practicing safer sex because of this advice. Blacks (adjusted odds ratio (AOR): 2.71; 95% confidence interval (CI): 1.36,5.42) and those reporting manic episodes (AOR: 2.41; 95% CI: 1.26,4.60) had higher odds of safe sex counseling. Neither race/ethnicity nor any indicator of mental illness was significantly associated with practicing safer sex because of counseling.
Those with past manic episodes reported more safe sex counseling, which is appropriate given that hypersexuality is a known symptom of mania. Black patients reported more safe sex counseling than white patients, despite controlling for sexual risk. One potential explanation is that counseling was conducted based on assumptions about sexual risk behaviors and patient race. There were no significant disparities in self-reported safer sex practices because of counseling, suggesting that increased counseling did not differentially affect safe sex behavior for black patients and those with manic episodes. Exploring the basis of how patient characteristics can influence counseling and resultant behavior merits further exploration to help reduce disparities in safe sex counseling and outcomes.
Counseling; Disparities; Sexual behavior; Stereotyping
Female sex workers (FSWs) are the group at greatest risk for human immunodeficiency virus (HIV) infection in India. Women and girls trafficked (ie, forced or coerced) into sex work are thought to be at even greater risk because of high exposure to violence and unprotected sex, particularly during the early months of sex work, that is, at initiation. Surveys were completed with HIV-infected FSWs (n = 211) recruited from an HIV-related service organization in Mumbai, India. Approximately 2 in 5 participants (41.7%) reported being forced or coerced into sex work. During the first month in sex work, such FSWs had higher odds of sexual violence (adjusted odds ratio [AOR], 3.1; 95% confidence interval [CI], 1.6–6.1), ≥7 clients per day (AOR, 3.3; 1.8–6.1), no use of condoms (AOR, 3.8, 2.1–7.1), and frequent alcohol use (AOR, 1.9; 1.0–3.4) than HIV-infected FSWs not entering involuntarily. Those trafficked into sex work were also at higher odds for alcohol use at first sex work episode (AOR, 2.2; 95% CI, 1.2–4.0). These results suggest that having been trafficked into sex work is prevalent among this population and that such FSWs may face high levels of sexual violence, alcohol use, and exposure to HIV infection in the first month of sex work. Findings call into question harm reduction approaches to HIV prevention that rely primarily on FSW autonomy.
Unhealthy alcohol use (the spectrum of risky use through dependence) is common in HIV-infected persons, yet it can interfere with HIV medication adherence, may lower CD4 cell count, and can cause hepatic injury. Carbohydrate-deficient transferrin (CDT), often measured as %CDT, can detect heavy drinking but whether it does in people with HIV is not well established.
We evaluated the operating characteristics of %CDT in HIV-infected adults using cross-sectional data from 300 HIV-infected adults with current or past alcohol problems. Past 30-day alcohol consumption was determined using the Timeline Followback, a validated structured recall questionnaire, as the reference standard. Sensitivity and specificity of %CDT (at manufacturer's cutoff point of 2.6%) for detecting both “at-risk” (≥four drinks per occasion or >seven drinks per week for women, ≥five drinks per occasion or >14 per week for men) and “heavy” drinking (≥ four drinks per day for women, ≥ five drinks per day for men on at least seven days) were calculated. Receiver operating characteristic (ROC) curves were estimated to summarize the diagnostic ability of %CDT for distinguishing “at risk” and “heavy” levels of drinking. Exploratory analyses that stratified by gender and viral hepatitis infection were performed.
Of 300 subjects, 103 reported current consumption at “at-risk” amounts, and 47 reported “heavy” amounts. For “at-risk” drinking, sensitivity of %CDT was 28% (95% confidence interval (CI) 19%, 37%), specificity 90% (95% CI 86%, 94%); area under the ROC curve (AUC) was 0.59. For “heavy” drinking, sensitivity was 36% (95% CI 22%, 50%), specificity 88% (95% CI 84%, 92%); AUC was 0.60.
Sensitivity appeared lower among women and those with viral hepatitis; specificity was similar across subgroups. Among HIV-infected adults, %CDT testing yielded good specificity, but poor sensitivity for detecting “at-risk” and “heavy” alcohol consumption, limiting its clinical utility for detecting unhealthy alcohol use in this population.
carbohydrate-deficient transferrin; CDT; alcohol; HIV
Little is known about how different types of substances affect oral health. Our objective was to examine the respective effects of alcohol, stimulants, opioids, and marijuana on oral health in substance-dependent persons. Using self-reported data from 563 substance-dependent individuals, we found that most reported unsatisfactory oral health, with their most recent dental visit more than 1 year ago. In multivariable logistic regressions, none of the substance types were significantly associated with oral health status. However, opioid use was significantly related to a worse overall oral health rating compared to 1 year ago. These findings highlight the poor oral health of individuals with substance dependence and the need to address declining oral health among opioid users. General health and specialty addiction care providers should be aware of oral health problems among these patients. In addition, engagement into addiction and medical care may be facilitated by addressing oral health concerns.
Oral health; Substance dependence; Dental care
The association between smoking and HIV disease progression has been examined in several studies; however, findings have been inconsistent. We examined the effect of recent cigarette smoking on CD4+ T cell count/µL (CD4 count) and HIV RNA concentration (HIV viral load [VL]) among two HIV-infected cohorts with alcohol problems in Massachusetts in the periods 1997–2001 and 2001–2006 using a prospective cohort design and linear mixed models. Smoking groups were defined as: minimal or non-smokers, light smokers, moderate smokers and heavy smokers. Age, alcohol use, injection drug use, depressive symptoms, gender, annual income, and antiretroviral therapy (ART) adherence were considered as potential confounders. Among 462 subjects, no significant differences in CD4 count or viral load were found between smoking groups. Using minimal or non-smokers as the reference group, the adjusted mean differences in CD4 count were: 8.2 (95% confidence interval (CI): −17.4, 33.8) for heavy smokers; −0.1 (95% CI: −25.4, 5.1) for moderate smokers; and −2.6 (95% CI: −28.3, 3.0) for light smokers. For log10 VL, the adjusted differences were: 0.03 (95% CI: −0.12, 0.17) for heavy smokers; −0.06 (95% CI: −0.20, 0.08) for moderate smokers; and 0.14 (95% CI −0.01, 0.28) for light smokers. This study did not find an association between smoking cigarettes and HIV disease progression as measured by CD4 cell count and VL.
Cigarette Smoking; CD4+ T cells; Viral Load; HIV
Structural equation models (SEMs) provide a general framework for analyzing mediated longitudinal data. However when interest is in the total effect (i.e. direct plus indirect) of a predictor on the binary outcome, alternative statistical techniques such as non-linear mixed models (NLMM) may be preferable, particularly if specific causal pathways are not hypothesized or specialized SEM software is not readily available. The purpose of this paper is to evaluate the performance of the NLMM in a setting where the SEM is presumed optimal.
We performed a simulation study to assess the performance of NLMMs relative to SEMs with respect to bias, coverage probability, and power in the analysis of mediated binary longitudinal outcomes. Both logistic and probit models were evaluated. Models were also applied to data from a longitudinal study assessing the impact of alcohol consumption on HIV disease progression.
For the logistic model, the NLMM adequately estimated the total effect of a repeated predictor on the repeated binary outcome and were similar to the SEM across a variety of scenarios evaluating sample size, effect size, and distributions of direct vs. indirect effects. For the probit model, the NLMM adequately estimated the total effect of the repeated predictor, however, the probit SEM overestimated effects.
Both logistic and probit NLMMs performed well relative to corresponding SEMs with respect to bias, coverage probability and power. In addition, in the probit setting, the NLMM may produce better estimates of the total effect than the probit SEM, which appeared to overestimate effects.
To understand patterns of alcohol consumption and baseline factors associated with favorable drinking patterns among HIV-infected patients.
We studied drinking patterns among HIV-infected patients with current or past alcohol problems. We assessed drinking status in 6 month intervals. Based on National Institute on Alcohol Abuse and Alcoholism guidelines a favorable drinking pattern was defined as not drinking risky amounts at each assessment or decreased drinking over time. All other patterns were defined as unfavorable. Logistic regression models were used to identify baseline factors associated with a favorable pattern.
Among 358 subjects, 54% had a favorable drinking pattern with 44% not drinking risky amounts at every assessment, and 11% decreasing consumption over time. Of the 46% with an unfavorable pattern, 4% drank risky amounts each time, 5% increased, and 37% both decreased and increased consumption over time. Current alcohol dependence and recent marijuana use were negatively associated with a favorable pattern, while older age and female gender, and having a primary HIV risk factor of injection drug use were positively associated with a favorable pattern.
Many HIV-infected adults with alcohol problems have favorable drinking patterns over time, and alcohol consumption patterns are not necessarily constant. Identifying HIV-infected adults with a pattern of risky drinking may require repeated assessments of alcohol consumption.
Alcohol; HIV; drinking patterns
Chronic medical diseases require regular and longitudinal care and self-management for effective treatment. When chronic diseases include substance use disorders, care and treatment of both the medical and addiction disorders may affect access to care and the ability to focus on both conditions. The objective of this paper is to evaluate the association between the presence of chronic medical disease and recent addiction treatment utilization among adults with substance dependence.
Cross-sectional secondary data analysis of self-reported baseline data from alcohol and/or drug-dependent adults enrolled in a randomized clinical trial of a disease management program for substance dependence in primary care. The main independent variable was chronic medical disease status, categorized using the Katz Comorbidity Score as none, single condition of lower severity, or higher severity (multiple conditions or single higher severity condition), based on comorbidity scores determined from self-report. Asthma was also examined in secondary analyses. The primary outcome was any self-reported addiction treatment utilization (excluding detoxification) in the 3 months prior to study entry, including receipt of any addiction-focused counseling or addiction medication from any healthcare provider. Logistic regression models were adjusted for sociodemographics, type of substance dependence, recruitment site, current smoking, and recent anxiety severity.
Of 563 subjects, 184 (33%) reported any chronic disease (20% low severity; 13% higher severity) and 111 (20%) reported asthma; 157 (28%) reported any addiction treatment utilization in the past 3 months. In multivariate regression analyses, no significant effect was detected for chronic disease on addiction treatment utilization (adjusted odds ratio [AOR] 0.88 lower severity vs. none, 95% confidence interval (CI): 0.60, 1.28; AOR 1.29 higher severity vs. none, 95% CI: 0.89, 1.88) nor for asthma.
In this cohort of alcohol and drug dependent persons, there was no significant effect of chronic medical disease on recent addiction treatment utilization. Chronic disease may not hinder or facilitate connection to addiction treatment.
addiction; substance abuse; substance abuse; treatment; medical care; chronic disease
Prevalence of unhealthy alcohol use among medical inpatients is high.
To characterize the course and outcomes of unhealthy alcohol use, and factors associated with these outcomes.
Prospective cohort study.
A total of 287 medical inpatients with unhealthy alcohol use.
At baseline and 12 months later, consumption and alcohol-related consequences were assessed. The outcome of interest was a favorable drinking outcome at 12 months (abstinence or drinking “moderate” amounts without consequences). The independent variables evaluated included demographics, physical/sexual abuse, drug use, depressive symptoms, alcohol dependence, commitment to change (Taking Action), spending time with heavy-drinking friends and receipt of alcohol treatment (after hospitalization). Adjusted regression models were used to evaluate factors associated with a favorable outcome.
Thirty-three percent had a favorable drinking outcome 1 year later. Not spending time with heavy-drinking friends [adjusted odds ratio (AOR) 2.14, 95% CI: 1.14–4.00] and receipt of alcohol treatment [AOR (95% CI): 2.16(1.20–3.87)] were associated with a favorable outcome. Compared to the first quartile (lowest level) of Taking Action, subjects in the second, third and highest quartiles had higher odds of a favorable outcome [AOR (95% CI): 3.65 (1.47, 9.02), 3.39 (1.38, 8.31) and 6.76 (2.74, 16.67)].
Although most medical inpatients with unhealthy alcohol use continue drinking at-risk amounts and/or have alcohol-related consequences, one third are abstinent or drink “moderate” amounts without consequences 1 year later. Not spending time with heavy-drinking friends, receipt of alcohol treatment and commitment to change are associated with this favorable outcome. This can inform efforts to address unhealthy alcohol use among patients who often do not seek specialty treatment.
unhealthy alcohol use; medical inpatients; factors associated with drinking and consequences
The efficacy of screening and brief intervention (SBI) for drug use in primary care patients is largely unknown. Because of this lack of evidence, US professional organizations do not recommend it. Yet, a strong theoretical case can be made for drug SBI. Drug use is common and associated with numerous health consequences, patients usually do not seek help for drug abuse and dependence, and SBI has proven efficacy for unhealthy alcohol use. On the other hand, the diversity of drugs of abuse and the high prevalence of abuse and dependence among those who use them raise concerns that drug SBI may have limited or no efficacy. Federal efforts to disseminate SBI for drug use are underway, and reimbursement codes to compensate clinicians for these activities have been developed. However, the discrepancies between science and policy developments underscore the need for evidence-based research regarding the efficacy of SBI for drug use. This article discusses the rationale for drug SBI and existing research on its potential to improve drug-use outcomes and makes the argument that randomized controlled trials to determine its efficacy are urgently needed to bridge the gap between research, policy, and clinical practice.
addiction; drug use; primary care; drug screening; brief intervention
Unprotected heterosexual transactional sex plays a central role in the spread of HIV in India. Given alcohol’s association with risky sex in other populations and alcohol’s role in HIV disease progression, we investigated patterns of alcohol use in HIV-infected female sex workers (FSWs) and HIV-infected male clients of FSWs in Mumbai. Analyses identified factors associated with heavy alcohol use and evaluated the relationship between alcohol use and risky sex. We surveyed 211 female and 205 male individuals; 80/211 FSWs (38%) and 127/205 male clients (62%) drank alcohol in the last 30 days. Among females, 32 and 11% drank heavily and were alcohol-dependent, respectively; among males the respective proportions were 44 and 29%. Men’s heavy alcohol use was significantly associated with inconsistent condom use over the last year (AOR 2.40, 95% CI 1.21–4.77, P = 0.01); a comparable association was not seen in women. These findings suggest a need to address alcohol use both to avoid the medical complications of its heavy use in this population and to mitigate inconsistent condom use, the latter issue possibly requiring gender specific approaches. Such efforts to reduce drinking will be an important dimension to secondary HIV prevention in India.
Alcohol; Transactional sex; HIV; Female sex workers
Unhealthy alcohol use is common in medical inpatients, and hospitalization has been hypothesized to serve as a “teachable moment” that could motivate patients to decrease drinking, but studies of hospital-based brief interventions have often not found decreases. Evaluating associations between physical health and subsequent drinking among medical inpatients with unhealthy alcohol use could inform refinement of hospital-based brief interventions by identifying an important foundation on which to build them. We tested associations between poor physical health and drinking after hospitalization and whether associations varied by alcohol dependence status and readiness to change.
Participants were medical inpatients who screened positive for unhealthy alcohol use and consented to participate in a randomized trial of brief intervention (n=341). Five measures of physical health were independent variables. Outcomes were abstinence and the number of heavy drinking days (HDDs) reported in the 30 days prior to interviews 3 months after hospitalization. Separate regression models were fit to evaluate each independent variable controlling for age, gender, randomization group, and baseline alcohol use. Interactions between each independent variable and alcohol dependence and readiness to change were tested. Stratified models were fit when significant interactions were identified.
Among all participants, measures of physical health were not significantly associated with either abstinence or number of HDDs at 3 months. Having an alcohol-attributable principal admitting diagnosis was significantly associated with fewer HDDs in patients who were non-dependent [adjusted incidence rate ratio (aIRR) 0.10, 95% CI 0.03 – 0.32] or who had low alcohol problem perception (aIRR 0.36, 95% CI 0.13 – 0.99) at hospital admission. No significant association between alcohol-attributable principal admitting diagnosis and number of HDDs was identified for participants with alcohol dependence or high problem perception.
Among medical inpatients with non-dependent unhealthy alcohol use and those who do not view their drinking as problematic, alcohol-attributable illness may catalyze decreased drinking. Brief interventions that highlight alcohol-related illness might be more successful.
Linear mixed models (LMMs) are frequently used to analyze longitudinal data. Although these models can be used to evaluate mediation, they do not directly model causal pathways. Structural equation models (SEMs) are an alternative technique that allows explicit modeling of mediation. The goal of this paper is to evaluate the performance of LMMs relative to SEMs in the analysis of mediated longitudinal data with time-dependent predictors and mediators. We simulated mediated longitudinal data from an SEM and specified delayed effects of the predictor. A variety of model specifications were assessed, and the LMMs and SEMs were evaluated with respect to bias, coverage probability, power, and Type I error. Models evaluated in the simulation were also applied to data from an observational cohort of HIV-infected individuals. We found that when carefully constructed, the LMM adequately models mediated exposure effects that change over time in the presence of mediation, even when the data arise from an SEM.
To assess whether smoke-free restaurant laws influence the progression from (1) never smoking to early experimentation and (2) early experimentation to established smoking.
A longitudinal, 4-year, 3-wave study of a representative sample of Massachusetts youth.
A total of 301 Massachusetts communities.
Study participants were 3834 Massachusetts youths aged 12 to 17 years at baseline, from January 2, 2001, to June 18, 2002, of whom 2791 (72.8%) were reinterviewed after 2 years (from January 30, 2003, to July 31, 2004) and 2217 (57.8%) were reinterviewed after 4 years (from February 16, 2005, to March 26, 2006). Wave 3 respondents were recruited from both those who responded at wave 2 and those who did not.
The primary predictor of interest is the strength of the local restaurant smoking regulation in the respondents’ town of residence at the baseline of each transition period.
Main Outcome Measures
(1) Overall progression to established smoking (having smoked ≥100 cigarettes in one’s lifetime), (2) transition from nonsmoking (never having puffed a cigarette) to experimentation, and (3) transition from experimentation to established smoking.
Youths living in towns with a strong restaurant smoking regulation at baseline had significantly lower odds of progressing to established smoking (odds ratio, 0.60; 95% confidence interval, 0.42–0.85) compared with those living in towns with weak regulations. The observed association between strong restaurant smoking regulations and impeded progression to established smoking was entirely due to an effect on the transition from experimentation to established smoking (odds ratio, 0.53; 95% confidence interval, 0.33–0.86).
Local smoke-free restaurant laws may significantly lower youth smoking initiation by impeding the progression from cigarette experimentation to established smoking.
Opioid-dependent patients often have co-occurring chronic illnesses requiring medications that interact with methadone. Methadone maintenance treatment (MMT) is typically provided separately from medical care. Hence, coordination of medical care and substance use treatment is important to preserve patient safety.
To identify potential safety risks among MMT patients engaged in medical care by evaluating the frequency that opioid dependence and MMT documentation are missing in medical records and characterizing potential medication-methadone interactions.
Among patients from a methadone clinic who received primary care from an affiliated, but separate, medical center, we reviewed electronic medical records for documentation of methadone, opioid dependence, and potential drug-methadone interactions. The proportions of medical records without opioid dependence and methadone documentation were estimated and potential medication-methadone interactions were identified.
Among the study subjects ( = 84), opioid dependence documentation was missing from the medical record in 30% (95% CI, 20%–41%) and MMT documentation was missing from either the last primary care note or the last hospital discharge summary in 11% (95% CI, 5%-19%). Sixty-nine percent of the study subjects had at least 1 medication that potentially interacted with methadone; 19% had 3 or more potentially interacting medications.
Among patients receiving MMT and medical care at different sites, documentation of opioid dependence and MMT in the medical record occurs for the majority, but is missing in a substantial number of patients. Most of these patients are prescribed medications that potentially interact with methadone. This study highlights opportunities for improved coordination between medical care and MMT.
methadone; medication interactions; patient safety; care coordination
We studied whether readiness to change predicts alcohol consumption (drinks per day) 3 months later in 267 medical inpatients with unhealthy alcohol use. We used 3 readiness to change measures: a 1 to 10 visual analog scale (VAS) and two factors of the Stages of Change Readiness and Treatment Eagerness Scale: Perception of Problems (PP) and Taking Action (TA). Subjects with the highest level of VAS-measured readiness consumed significantly fewer drinks 3 months later [Incidence rate ratio (IRR) and 95% confidence interval (CI): 0.57 (0.36, 0.91) highest vs. lowest tertile]. Greater PP was associated with more drinking [IRR (95%CI): 1.94 (1.02, 3.68) third vs. lowest quartile]. Greater TA scores were associated with less drinking [IRR (95%CI): 0.42 (0.23, 0.78) highest vs. lowest quartile]. Perception of Problems' association with more drinking may reflect severity rather than an aspect of readiness associated with ability to change; high levels of Taking Action appear to predict less drinking. Although assessing readiness to change may have clinical utility, assessing the patient's planned actions may have more predictive value for future improvement in alcohol consumption.
unhealthy alcohol use; readiness to change; medical inpatients; Stages of Change Readiness and Treatment Eagerness Scale (SOCRATES)
To determine whether adolescents living in parental homes where smoking is banned are more likely to move into smoke-free living quarters when they leave home.
We analyzed data on 693 youths from a four-year, three-wave prospective study of a representative sample of Massachusetts adolescents (aged 12–17). All youths resided in independent living quarters at follow-up. The primary outcome was presence of a smoking ban in the living quarters at follow-up. The primary predictor was presence of a household smoking ban in the parental home, assessed two years prior to the outcome. Generalized linear mixed effects models examined the effect of a parental household smoking ban on the odds of moving into smoke-free living quarters at follow-up overall and stratified by smoking status at follow-up.
Youths leaving home had much higher odds of moving to smoke-free living quarters if their parental household had had a smoking ban (odds ratio [OR] = 12.70, 95% CI, 6.19–26.04). Other independent predictors included moving into a school or college residence (odds ratio [OR] = 3.88, 95% CI 1.87–8.05), and not living with smokers at follow-up (odds ratio [OR] = 3.91, 95% CI 1.93–7.92).
A household smoking ban in the parental home appears to lead youth to prefer smoke-free living quarters once youths leave home.
adolescent health; health policy; smoking; tobacco smoke pollution
Linear mixed effects models (LMMs) are a common approach for analyzing longitudinal data in a variety of settings. Although LMMs may be applied to complex data structures, such as settings where mediators are present, it is unclear whether they perform well relative to methods for mediational analyses such as structural equation models (SEMs), which have obvious appeal in such settings. For some researchers, SEMs may be more difficult than LMMs to implement, e.g. due to lack of training in the methodology or the need for specialized SEM software. It therefore is of interest to evaluate whether the LMM performs sufficiently in a scenario particularly suitable for SEMs. We focus on evaluation of the total effect (i.e. direct and indirect) of an exposure on an outcome of interest when a mediating factor is present. Our aim is to explore whether the LMM performs as well as the SEM in a setting that is conducive to using the SEM.
We simulated mediated longitudinal data from an SEM where a binary, main independent variable has both direct and indirect effects on a continuous outcome. We conducted analyses with both the LMM and SEM to evaluate the performance of the LMM in a setting where the SEM is expected to be preferable. Models were evaluated with respect to bias, coverage probability and power. Sample size, effect size and error distribution of the simulated data were varied.
Both models performed well in a range of settings. Marginal increases in power estimates were observed for the SEM, although generally there were no major differences in performance. Power for both models was good with a sample of size of 250 and a small to medium effect size. Bias did not substantially increase for either model when data were generated from distributions that were both skewed and kurtotic.
In settings where the goal is to evaluate the overall effects, the LMM excluding mediating variables appears to have good performance with respect to power, bias and coverage probability relative to the SEM. The major benefit of SEMs is that it simultaneously and efficiently models both the direct and indirect effects of the mediation process.
Lipodystrophy is a common long-term complication of HIV infection that may lead to decreased quality of life and less adherence to antiretroviral therapy (ART). A complete understanding of the etiology of HIV-associated lipodystrophy has not as yet been achieved, although factors related to the virus, per se, and use of ART appear to be related. Alcohol use is common among HIV-infected patients and has biological effects on fat distribution, yet alcohol’s relationship to HIV-associated lipodystrophy has not been examined. The goal of this clinical study was to assess the effect of alcohol consumption on lipodystrophy in HIV-infected adults with alcohol problems. This was a prospective study (2001 - 2006) of 289 HIV-infected persons with alcohol problems. The primary outcome was self-reported lipodystrophy, which was assessed at one timepoint (median 29 months after enrollment). Alcohol use was assessed every 6 months and classified as: abstinent at all interviews; ≥1 report of moderate drinking but no heavy drinking; 1 or 2 reports of heavy drinking; or ≥3 reports of heavy drinking. Multivariable logistic regression models were fit to the data. Fifty-two percent (150/289) of subjects reported lipodystrophy. Alcohol consumption was: 34% abstinent at all interviews; 12% ≥1 report of moderate drinking, but no heavy drinking; 34% 1-2 reports of heavy drinking; 20% ≥3 reports of heavy drinking. Although not statistically significant, subjects with alcohol use had a higher odds of lipodystrophy [adjusted odds ratios and 95% CI: ≥1 report of moderate drinking, 2.36 (0.89, 6.24); 1-2 reports of heavy drinking, 1.34 (0.69, 2.60); ≥3 reports of heavy drinking, 2.07 (0.90, 4.73)]. Alcohol use may increase the odds of developing HIV-associated lipodystrophy among subjects with alcohol problems. However, larger studies are needed to elucidate fully the role and impact of alcohol consumption on the development of this common long-term complication of HIV infection and its treatment.
lipodystrophy; HIV; alcohol consumption
To examine the effect of smoking regulations in local restaurants on anti‐smoking attitudes and quitting behaviours among adult smokers.
Hierarchical linear modelling (HLM) was used to assess the relationship between baseline strength of town‐level restaurant smoking regulation and follow‐up (1) perceptions of the social acceptability of smoking and (2) quitting behaviours.
Each of the 351 Massachusetts towns was classified as having strong (complete smoking ban) or weak (all other and no smoking restrictions) restaurant smoking regulations.
1712 adult smokers of Massachusetts aged ⩾18 years at baseline who were interviewed via random‐digit‐dial telephone survey in 2001–2 and followed up 2 years later.
Main outcome measures
Perceived social acceptability of smoking in restaurants and bars, and making a quit attempt and quitting smoking.
Among adult smokers who had made a quit attempt at baseline, living in a town with a strong regulation was associated with a threefold increase in the odds of making a quit attempt at follow‐up (OR = 3.12; 95% CI 1.51 to 6.44). Regulation was found to have no effect on cessation at follow‐up. A notable, although marginal, effect of regulation was observed for perceiving smoking in bars as socially unacceptable only among smokers who reported at baseline that smoking in bars was socially unacceptable.
Although local restaurant smoking regulations did not increase smoking cessation rates, they did increase the likelihood of making a quit attempt among smokers who had previously tried to quit, and seem to reinforce anti‐social smoking norms among smokers who already viewed smoking in bars as socially unacceptable.
To determine whether adolescents living in households where smoking is banned are more likely to develop anti-smoking attitudes and less likely to progress to smoking.
A longitudinal, four-year, three-wave study of a representative sample of 3,834 Massachusetts youths ages12-17 at baseline, of whom 2,791 (72.8%) were re-interviewed after two years and 2,217 (57.8%) were re-interviewed after four years. We used a three-level hierarchical linear model (HLM) to analyze the effect of a household ban on anti-smoking attitudes and smoking behaviors.
The absence of a household smoking ban increased the odds that youths perceived a high prevalence of adult smoking, both among youths living with a smoker (odds ratio [OR] = 1.56, 95% CI, 1.15-2.13) and those living with nonsmokers (odds ratio [OR] = 1.75, 95% CI, 1.29-2.37). Among youths who live with nonsmokers, those with no home ban were more likely to transition from nonsmoking to early experimentation (OR = 1.89; 95% CI, 1.30-2.74) compared to those with a ban.
Home bans may promote anti-smoking attitudes among youths and reduce progression to smoking experimentation among youths who live with nonsmokers.
health policy; youth smoking; tobacco smoke pollution
Some primary care physicians do not conduct alcohol screening because they assume their patients do not want to discuss alcohol use.
To assess whether (1) alcohol counseling can improve patient-perceived quality of primary care, and (2) higher quality of primary care is associated with subsequent decreased alcohol consumption.
A prospective cohort study.
Two hundred eighty-eight patients in an academic primary care practice who had unhealthy alcohol use.
The primary outcome was quality of care received [measured with the communication, whole-person knowledge, and trust scales of the Primary Care Assessment Survey (PCAS)]. The secondary outcome was drinking risky amounts in the past 30 days (measured with the Timeline Followback method).
Alcohol counseling was significantly associated with higher quality of primary care in the areas of communication (adjusted mean PCAS scale scores: 85 vs. 76) and whole-person knowledge (67 vs. 59). The quality of primary care was not associated with drinking risky amounts 6 months later.
Although quality of primary care may not necessarily affect drinking, brief counseling for unhealthy alcohol use may enhance the quality of primary care.
alcohol; counseling; brief intervention; quality of primary care
Buprenorphine is a safe, effective and underutilized treatment for opioid dependence that requires special credentialing, known as a waiver, to prescribe in the United States.
To describe buprenorphine clinical practices and barriers among office-based physicians.
Two hundred thirty-five office-based physicians waivered to prescribe buprenorphine in Massachusetts.
Questionnaires mailed to all waivered physicians in Massachusetts in October and November 2005 included questions on medical specialty, practice setting, clinical practices, and barriers to prescribing. Logistic regression analyses were used to identify factors associated with prescribing.
Prescribers were 66% of respondents and prescribed to a median of ten patients. Clinical practices included mandatory counseling (79%), drug screening (82%), observed induction (57%), linkage to methadone maintenance (40%), and storing buprenorphine notes separate from other medical records (33%). Most non-prescribers (54%) reported they would prescribe if barriers were reduced. Being a primary care physician compared to a psychiatrist (AOR: 3.02; 95% CI: 1.48–6.18) and solo practice only compared to group practice (AOR: 3.01; 95% CI: 1.23–7.35) were associated with prescribing, while reporting low patient demand (AOR: 0.043, 95% CI: 0.009–0.21) and insufficient institutional support (AOR: 0.37; 95% CI: 0.15–0.89) were associated with not prescribing.
Capacity for increased buprenorphine prescribing exists among physicians who have already obtained a waiver to prescribe. Increased efforts to link waivered physicians with opioid-dependent patients and initiatives to improve institutional support may mitigate barriers to buprenorphine treatment. Several guideline-driven practices have been widely adopted, such as adjunctive counseling and monitoring patients with drug screening.
opioid dependence; buprenorphine; medication assisted treatment