Chris G. Richardson

Sense of coherence as a moderator of the effects of stressful life events on health

Study objective: To test the hypothesis that Antonovsky’s concept of sense of coherence (SOC) moderates (that is, buffers) the health impacts of stressful life events in a population based sample. Design: Multiple linear and Poisson regression analyses of longitudinal data from a national survey of population health were used to examine the relations among SOC, the experience of recent stressful life events (for example, family breakdown, financial crisis, physical abuse), and two outcomes, self reported health status (SRH) and self reported number of physician visits during the previous year. Setting: General population of Canada. Participants: Nationally representative sample of household residents aged 30 years of age or greater surveyed in 1998 and 2000 (n = 6505). Main results: After controlling for age, sex, and previous health status, a significant moderating effect (t = 2.24, p = 0.025) in the expected direction was found on respondents’ SRH. The mean difference in SRH between those who did and did not experience a recent stressful life event was 0.24 (95% CI: 0.16, 0.32) in people with a below average SOC and 0.04 (95% CI: −0.04, 0.11) in people with a higher than average SOC score. The postulated moderating effect of SOC was not significant (t = 1.1, p>0.05) in predicting the number of visits to a physician. Conclusions: SOC seems to buffer the impact of recent stressful life events on SRH.

Elevation in Cardiovascular Disease Risk in South Asians Is Mediated by Differences in Visceral Adipose Tissue

South Asians have a higher risk for cardiovascular disease (CVD) that remains largely unexplained. We hypothesized that the increased CVD risk in South Asians compared to Europeans is mediated through higher levels of visceral adipose tissue (VAT) in South Asians compared to total body fat and subcutaneous abdominal adipose tissue (SAT). South Asians (207) and Europeans (201) underwent assessment for demographics, body fat, and risk factors. Linear regression models were created by sex for each risk factor to explore mediation effects of total body fat, SAT, and VAT adjusted for age, income, smoking, and BMI (menopausal status for women). Mediation was based on changes in the ethnicity β coefficient due to additional adjustment for our adipose variable of interest and the Sobel test for mediation. South Asians had worse lipid, glucose, insulin, and C‐reactive protein (CRP) levels than Europeans after adjusting for confounders. Most of these differences remained even after further adjustment by either total body fat or SAT. In contrast, VAT attenuated the ethnic differences in risk factors by 16%–52%. After adjusting for VAT, there were no longer ethnic differences in total cholesterol (TC), LDL‐C, TC/HDL‐C, glucose, and diastolic blood pressure (BP) in men, and in HDL‐C, triglycerides (TG), TC/HDL‐C, and homeostasis model (HOMA) in women, and VAT was a significant mediator for these risk factors. Higher levels of risk factors for CVD in South Asians are predominantly because of the unique phenotype of South Asians having greater VAT than Europeans even at the same BMI.

Stress and depression in students: the mediating role of stress management self-efficacy.

Background:The prevalence of mental health issues appears to be increasing. Stress that leads to depression may be mediated if people believe that they have the wherewithal to manage it. Objective:The aim of this study was to examine the extent to which the relationship between adverse stress and depression is mediated by university students’ perceived ability to manage their stress. Method:Students were sampled randomly at a Canadian university in 2006 (n = 2,147) and 2008 (n = 2,292). Data about students’ stress (1 item), depression (4 items), stress management self-efficacy (4 items), and their demographics were obtained via the online National College Health Assessment survey and analyzed using confirmatory factor analysis and latent variable mediation modeling. Results:Greater stress management self-efficacy was associated with lower depression scores for students whose stress impeded their academic performance, irrespective oftheir gender and age (total R2depression = 41%). The relationship between stress and depression was mediated partially by stress management self-efficacy (37% to 55% mediation, depending on the severity of stress). Conclusions:Identifying students with limited stress management self-efficacy and providing them with appropriate supportive services may help them to manage stress and prevent depression.

Adolescents' self-defined tobacco use status, marijuana use, and tobacco dependence.

AIMS To examine differences in tobacco use and dependence between adolescents who are and are not marijuana users. DESIGN Cross-sectional analysis of existing survey data. PARTICIPANTS Data were obtained from 7440 adolescents who completed the British Columbia Youth Survey of Smoking and Health II (BCYSOSH-II), a school based survey conducted in 2004. MEASURES Responses to demographic, current smoking, alcohol use, self-defined tobacco and marijuana use status questions, perceived physical and mental addiction to tobacco, modified-Fagerstrom Tolerance Questionnaire (M-FTQ), and the Dimensions of Tobacco Dependence Scale (DTDS) were obtained. FINDINGS Marijuana users were 5.9 times more likely to be current tobacco smokers and reported higher levels of perceived addiction to tobacco as compared with marijuana non-users. After controlling for demographics, life-time tobacco use, and alcohol use, marijuana use was associated with the nicotine dependent and sensory dimensions of tobacco dependence. CONCLUSIONS Adolescents who concurrently use tobacco and marijuana may be more tobacco dependent than are marijuana non-users. Concurrent use of marijuana may be a factor associated with tobacco dependence among a sub-group of concomitant drug-using adolescents.

Interventions to prevent the initiation of injection drug use: A systematic review

BACKGROUND Injection drug use has been identified as a key source of morbidity and mortality, primarily from overdose and the transmission of blood-borne diseases such as HIV. Experts have therefore called for the prioritization of resources toward the prevention of injection drug use. However, these strategies have not been systematically assessed. METHODS PRISMA guidelines were used to systematically review and extract findings from the peer-reviewed literature evaluating the effectiveness of interventions to prevent injecting initiation. We searched 10 English language electronic databases (PubMed, PsycINFO, EMBASE, Cochrane CENTRAL, CINAHL, Web of Science, TOXNET, AIDSLINE, AMED and ERIC), the Internet (Google, Google Scholar), and article reference lists, from database inception to June 1st, 2012. RESULTS Overall, out of 384 studies identified in the initial search, eight met the inclusion criteria. Studies evaluated four different types of interventions: social marketing, peer-based behavior modification, treatment, and drug law enforcement. Four studies observed a significant effect of the intervention on reducing rates of injecting initiation. Peer-based behavior modification and addiction treatment interventions were found to be most effective. Two of three studies assessing the impact of drug law enforcement on patterns of injecting initiation found no impact on injecting initiation, while one study reported inconclusive results. CONCLUSION There exists a limited scientific literature on strategies to prevent injecting initiation. Resources should be allocated toward increased research and development of effective interventions to prevent this phenomenon.

An Investigation of Smoking Cessation Video Content on YouTube

This study examines smoking cessation content posted on youtube.com. The search terms “quit smoking” and “stop smoking” yielded 2,250 videos in October 2007. We examined the top 100 as well as 20 randomly selected videos. Of these, 82 were directly relevant to smoking cessation. Fifty-one were commercial productions that included antismoking messages and advertisements for hypnosis and NicoBloc fluid. Thirty-one were personally produced videos that described personal experiences with quitting, negative health effects, and advice on how to quit. Although smoking cessation content is being shared on YouTube, very little is based on strategies that have been shown to be effective.

Crystal methamphetamine and initiation of injection drug use among street-involved youth in a Canadian setting

Background: Although injection drug use is known to result in a range of health-related harms, including transmission of HIV and fatal overdose, little is known about the possible role of synthetic drugs in injection initiation. We sought to determine the effect of crystal methamphetamine use on risk of injection initiation among street-involved youth in a Canadian setting. Methods: We used Cox regression analyses to identify predictors of injection initiation among injection-naive street-involved youth enrolled in the At-Risk Youth Study, a prospective cohort study of street-involved youth in Vancouver, British Columbia. Data on circumstances of first injection were also obtained. Results: Between October 2005 and November 2010, a total of 395 drug injection–naive, street-involved youth provided 1434 observations, with 64 (16.2%) participants initiating injection drug use during the follow-up period, for a cumulative incidence of 21.7 (95% confidence interval [CI] 1.7–41.7) per 100 person-years. In multivariable analysis, recent noninjection use of crystal methamphetamine was positively associated with subsequent injection initiation (adjusted hazard ratio 1.93, 95% CI 1.31–2.85). The drug of first injection was most commonly reported as crystal methamphetamine (14/31 [45%]). Interpretation: Noninjection use of crystal methamphetamine predicted subsequent injection initiation, and crystal methamphetamine was the most commonly used drug at the time of first injection. Evidence-based strategies to prevent transition to injection drug use among crystal methamphetamine users are urgently needed.

A test of the age-based measurement invariance and temporal stability of antonovsky's sense of coherence scale

The purpose of this investigation was to test the age-related measurement invariance and temporal stability of the 13-item version of Antonovskys Sense of Coherence Scale (SOC). Multigroup structural equation modeling of longitudinal data from the Canadian National Population Health Survey was used to examine the measurement invariance across 3 age groups (19 to 25 years, n = 1,257; 30 to 55 years, n = 5,326; and ≥60 years, n = 2,213) and to compare the stability of the SOC scores obtained in 1994 and 1998 in the same participants. The results support the age-related structural invariance of the scale. Differences in the latent means and stability coefficients obtained for the three age groups provide weak to moderate support for the stability of SOC scores over time in the general population of Canada.

An examination of the smoking identities and taxonomies of smoking behaviour of youth

Objective: To address observations that the smoking identities of youth are valid descriptors of their smoking behaviour, we examined the relationships between self-reported smoking identities, perceived levels of addiction, and established taxonomies of smoking behaviour of youth. Method: Cross-sectional data were collected on demographics, perceived extent of addiction to tobacco, smoking history, and self-reported smoking identity from questionnaires administered to 8225 students in British Columbia, Canada. A total of 7246 participants were categorised according to four smoking taxonomies established in the literature. Differences in perceived physical and mental addiction between smoking identity groups were calculated. The strength of the associations between the taxonomies of smoking and the smoking identity groups was also assessed. Results: There were significant differences in perceived levels of physical (Kruskal–Wallis χ2  3985.02, p<0.001) and mental (Kruskal–Wallis χ2  4046.09, p<0.001) addiction to tobacco by the participants’ self-reported smoking identity. Youth smoking identities were modestly associated with the established smoking taxonomies (Pearson C contingency coefficient  0.64–0.72). Conclusion: Self-reported smoking identities appear to provide valid characterisations of the smoking behaviour of youths that complement and elaborate existing taxonomies of smoking behaviour. Questions about self-reported smoking identity should be used in conjunction with smoking behaviour taxonomies when investigating youth smoking behaviours.

Empirical support for a multi-dimensional model of sensations experienced by youth during their initial smoking episodes.

Aims To examine the dimensionality of sensations experienced during initial tobacco smoking. Design Cross-sectional survey. Setting Thirteen secondary schools located in British Columbia, Canada. Participants Data from 1187 adolescents who responded ‘yes’ to the question: ‘Have you ever tried cigarette smoking, even one or two puffs?’. Measurements Participants answered questions about their demographic characteristics, tobacco smoking history and sensations experienced during their initial smoking episodes. Findings The sensations appear to represent the following three separate but modestly correlated dimensions: a pleasant dimension defined by feeling good and relaxed; an unpleasant dimension defined by coughing, feeling sick and nervous; and a ‘buzz’ dimension defined by feeling high and dizzy. The three factors made statistically significant contributions to the prediction of transition to regular smoking (defined as having smoked at least 100 cigarettes in ones life-time) after adjusting for age, sex and age at first puff. Conclusions The results suggest that three relatively distinct physiological systems appear to explain the relationship between initial smoking sensations and probability of becoming a regular smoker. Researchers examining sensations experienced during initial tobacco smoking episodes should consider using a three-dimensional profile of symptoms composed of pleasant, unpleasant and buzz dimensions.