Out-of-school time activity participation profiles of children with physical disabilities: a cluster analysis.

OBJECTIVE: To determine out-of-school activity participation profiles of school-aged children with physical disabilities. METHODS: Activity participation profiles were determined by cluster analysing 427 children's responses on multiple dimensions of participation (intensity, location, companionship, enjoyment, preference) in five activity types (recreational, active physical, social, skill-based, self-improvement). Socio-demographic, child, parent, family and environmental predictors of group membership were determined, along with child functioning, socio-demographic, self-concept and social support variables significantly associated with group membership. RESULTS: The cluster analysis revealed four groups, labelled Social Participators (a highly social and neighbourhood-focused group), Broad Participators (a group of high participators who enjoy participation), Low Participators (a group with low enjoyment and weak preferences) and Recreational Participators (a group of younger children who participate in recreational activities with family members). The groups showed meaningful differences across a range of socio-demographic, child, parent, family and environmental variables. CONCLUSIONS: The findings support an affective and contextual view of participation, indicating the importance of motivational theory and a person-environment approach in understanding the complexity of children's out-of-school activity participation.

Patterns and predictors of treatment seeking after onset of a substance use disorder.

BACKGROUND: We studied survey respondents aged 18 through 54 years to determine consistent predictors of treatment seeking after onset of a DSM-III-R substance use disorder. METHODS: Survey populations included a regional sample in Ontario (n = 6261), a national sample in the United States (n = 5388), and local samples in Fresno, Calif (n = 2874) and Mexico City, Mexico (n = 1734). The analysis examined the effects of demographics, symptoms, and types of substances on treatment seeking. RESULTS: Between 50% (Ontario) and 85% (Fresno) of people with substance use disorders seek treatment but the time lag between onset and treatment seeking averages a decade or more. Consistent predictors of treatment seeking include: (1) late onset of disorder (odds ratio [OR], 3.8; 95% confidence interval [CI], 2.6-5.6 for late [> or =30 years] vs early [1-15 years] age at first symptom of disorder); (2) recency of cohort (OR, 3.4; 95% CI, 2.3-5.0 for most recent [aged 15-24 years at interview] vs earliest [aged > or =45 years] cohorts); (3) 4 specific dependence symptoms (using larger amounts than intended, unsuccessful attempts to cut down use, tolerance, and withdrawal symptoms), with ORs ranging between 1.6 (95% CI, 1.3-2.0) and 2.7 (95% CI, 2.1-3.6) for people with vs without these symptoms; and (4) use vs nonuse of cocaine (OR, 2.1; 95% CI, 1.6-2.7) and heroin (OR, 2.6; 95% CI, 1.1-6.0). CONCLUSIONS: Although most people with substance use disorders eventually seek treatment, treatment seeking often occurs a decade or more after the onset of symptoms of disorder. While treatment seeking has increased in recent years, it is not clear whether this is because of increased access, increased demand, increased societal pressures, or other factors.

Alcohol use, alcohol disorders, and the use of health services: results from a population survey.

Data from a population survey were used to explore relationships among drinking levels/patterns, alcohol dependence or abuse, and the use of emergency services, hospital admissions, and frequent visits to general practitioners in the past year. For both males and females, self-reported hospital admissions were less common among daily moderate drinkers than among lifetime abstainers. Among males, drinkers with no history of alcohol dependence or abuse were less likely to report being in hospital in the last year than lifetime abstainers. For females, some groups defined by drinking patterns/levels and current drinkers without symptoms of alcohol abuse or dependence were more likely to report using emergency services than lifetime abstainers.

The influence of early and frequent use of marijuana on the risk of desistance and of progression to marijuana-related harm.

BACKGROUND: A significant minority of lifetime marijuana users will eventually receive a diagnosis of abuse or dependence. Yet little is known regarding the effect of age at onset and frequency of lifetime marijuana use on desistance from use and on progression to marijuana disorders. METHODS: To address this issue, data were obtained from a community sample of 2,729 lifetime marijuana users participating in the Ontario Mental Health Supplement. RESULTS: Early and frequent lifetime marijuana use was associated with highly persistent use and rapid progression to marijuana-related harm. Multivariate analyses revealed a monotonic increase in the risk of desistance with less frequent categories of use and later ages of onset. Results also indicated a threshold of use (100-199 times) associated with an elevated risk of developing marijuana disorders. A lower threshold of risk for marijuana problems was observed for females (50-99 times). CONCLUSIONS: Early and frequent marijuana use are potent risk factors for prolonging desistance and hastening marijuana-related harm. Required are prevention programs aimed at delaying the onset of first use as well as harm reduction strategies that encourage cessation or reduced levels of consumption among those already using.

Age at first alcohol use: a risk factor for the development of alcohol disorders.

OBJECTIVE: This study aimed to describe the natural course of DSM-III-R alcohol disorders as a function of age at first alcohol use and to investigate the influence of early use as a risk factor for progression to the development of alcohol disorders, exclusive of the effect of confounding influences. METHOD: Data were obtained from a community sample (N=5,856) of lifetime drinkers participating in the 1990-1991 Mental Health Supplement of the Ontario Health Survey. RESULTS: Survival analyses revealed a rapid progression to alcohol-related harm among those who reported having their first drink at ages 11-14. After 10 years, 13.5% of the subjects who began to drink at ages 11 and 12 met the criteria for a diagnosis of alcohol abuse, and 15.9% had a diagnosis of dependence. Rates for subjects who began to drink at ages 13 and 14 were 13.7% and 9.0%, respectively. In contrast, rates for those who started drinking at ages 19 and older were 2.0% and 1.0%. Unexpectedly, a delay in progression to harm was observed for the youngest drinkers (ages 10 and under). Hazard regression analyses revealed a nonlinear effect of age at first alcohol use, marked by an elevated risk of developing disorders among subjects first using alcohol at ages 11-14. CONCLUSIONS: First use of alcohol at ages 11-14 greatly heightens the risk of progression to the development of alcohol disorders and therefore is a reasonable target for intervention strategies that seek to delay first use as a means of averting problems later in life.

Lifetime use of professional and community services for help with drinking: results from a Canadian population survey.

OBJECTIVE: To determine the lifetime prevalence of help seeking for alcohol problems among Canadian drinkers; to explore the influence on help seeking of age, gender, education, marital status and the number of life areas where alcohol was felt to have caused harm; and to consider any similarities and differences in the rate of help seeking in Canada and in the U.S. METHOD: Analyses of data from a survey of 12,155 Canadian adults (response rate 75.6%) conducted in 1994. Use of logistic regression to examine the influence on help seeking of demographic characteristics and perceptions of alcohol-related harm. RESULTS: Two percent (2%) of lifetime drinkers reported seeking help at some time. Help from AA or from addictions agencies was reported by 1.3% and 0.3%, respectively. Logistic regression showed that help seeking was more common among those aged 40-49 years than those in other age groups, and less common among those with no post-secondary education and those who were married. The best predictor of help seeking was the number of life areas where alcohol was felt to have caused harm. Controlling for this variable, the influence of gender on help seeking was negligible. The rate of help seeking was similar to that in the U.S. 15 years earlier but lower than the U.S. rate in 1990. CONCLUSIONS: More effort may be required to encourage Canadians with alcohol problems to seek help. Gender does not appear to influence the chances of seeking some form of help when perceptions of harm are controlled. More research is needed to determine why proportionally fewer Canadian than American drinkers report seeking help for alcohol problems.

Predictors of the prevalence of tobacco use among Francophones and Anglophones in the province of Ontario.

This study examines Francophone/Anglophone differences in levels and patterns of tobacco use and associated risk factors in the province of Ontario, Canada. Estimates are derived from the self-administered portion of the 1990 Ontario Health Survey, a random probability survey of Ontario residents. The sample consists of 1127 Francophones and a random subset of 4023 Anglophones. Evidence, unique to Francophones, indicates a steady age-related decline in the median age of onset of daily cigarette consumption. Unlike Anglophones, multivariate results reveal that Francophones age 35-44 are significantly more likely than all other age groups to smoke cigarettes daily and to smoke a pack or more daily. Sub-groups within Ontario's Francophone community may be experiencing health-related risks associated with frequent and heavy consumption of cigarettes, and thus may be in need of addiction-related services.

Antecedents of the risk of recovery from DSM-III-R social phobia.

BACKGROUND: This study reports antecedents of recovery from DSM-III-R social phobia. METHODS: Retrospective data were obtained from 1116 individuals age 15 to 64 participating in a large population health survey in the province of Ontario, Canada RESULTS: Approximately 50% of the sample recovered from their illness. Survival analysis revealed a median length of illness of 25 years with peak periods of risk of recovery occurring between 30 and 45 years duration. Using discrete time multivariate hazard regression analysis, statistically significant predictors of recovery from social phobia included: childhood social contextual factors (one or no childhood siblings, a small town childhood place of residence), characteristics of the disorder (onset past the age of 7, less than three disorder symptoms), an absence of co-morbid health-related conditions and psychiatric disorders (chronic health problems and major depression), and the occurrence of co-morbid chronic health problems and major depression prior to the onset of the disorder. CONCLUSIONS: Our data indicate that social phobia in the general population is a chronic and unremittent disorder. Determinants of recovery are rooted in distal childhood circumstances, disorder attributes, and the physical and mental health status of individuals over the life course.

Elevation of blood pressure by genetic and pharmacological disruption of the ETB receptor in mice.

Exogenously administered endothelin (ET) elicits both pressor and depressor responses through the ETA and/or the ETB receptor on vascular smooth muscle cells and ETB on endothelial cells. To test whether ETB has pressor or depressor effects under basal physiological conditions, we determined arterial blood pressure (BP) in ETB-deficient mice obtained by crossing inbred mice heterozygous for targeted disruption of the ETB gene with mice homozygous for the piebald (s) mutation of the ETB gene (ETBs/s). F1 ETB-/s and ETB+/s progeny share an identical genetic background but have ETB levels that are approximately (1)/(8) and (5)/(8), respectively, of wild-type mice (ETB+/+). BP in ETB-/s mice was significantly higher, by approximately 20 mmHg, than that in ETB+/s or ETB+/+ mice. Immunoreactive ET-1 concentration in plasma as well as respiratory parameters was not different between ETB-/s and ETB+/s mice. A selective ETB antagonist, BQ-788, increased BP in ETB+/s and ETB+/+ but not in ETB-/s mice. Pretreatment with indomethacin, but not with NG-monomethyl-L-arginine, can attenuate the observed pressor response to BQ-788. The selective ETA antagonist BQ-123 did not ameliorate the increased BP in ETB-/s mice. Moreover, BP in mice heterozygous for targeted disruption of the ETA gene was not different from that in wild-type controls. These results suggest that endogenous ET elicits a depressor effect through ETB under basal conditions, in part through tonic production of prostaglandins, and not through secondary mechanisms involving respiratory control or clearance of circulating ET.

Childhood stress and symptoms of drug dependence in adolescence and early adulthood: social phobia as a mediator.

Retrospective data from 7,871 individuals age 16 to 64 were used to investigate whether, among those diagnosed with lifetime social phobia, its symptoms serve to link life events and chronic strains in childhood with symptoms of drug dependence in adulthood. Findings suggest social phobia as a pathway through which early life events and chronic strains affect the development of drug-related problems. Implications for research and clinical practice are discussed.

Comorbidity of substance use disorders with mood and anxiety disorders: results of the International Consortium in Psychiatric Epidemiology.

This article reports the results of a cross-national investigation of patterns of comorbidity between substance use and psychiatric disorders in six studies participating in the International Consortium in Psychiatric Epidemiology. In general, there was a strong association between mood and anxiety disorders as well as conduct and antisocial personality disorder with substance disorders at all sites. The results also suggest that there is a continuum in the magnitude of comorbidity as a function of the spectrum of substance use category (use, problems, dependence), as well as a direct relationship between the number of comorbid disorders and increasing levels of severity of substance use disorders (which was particularly pronounced for drugs). Finally, whereas there was no specific temporal pattern of onset for mood disorders in relation to substance disorders, the onset of anxiety disorders was more likely to precede that of substance disorders in all countries. These results illustrate the contribution of cross-national data to understanding the patterns and risk factors for psychopathology and substance use disorders.

Frequent childhood geographic relocation: its impact on drug use initiation and the development of alcohol and other drug-related problems among adolescents and young adults.

Early geographic relocation has been implicated as an important correlate of psychopathology, learning difficulties, and behavioural problems among child and adolescent populations, yet systematic studies of the potential influence of relocation on youthful drug use have not been conducted. This study explored the relationship between number of geographic moves before the age of 16 and the timing of onset of drug use and progression to drug-related problems. Data were obtained from 3,700 young adults aged 18 to 35 years participating in the 1990-1991 Ontario Mental Health Supplement, a large random probability survey of the residents of the Province of Ontario, Canada. Holding constant potential confounding factors, results showed highly significant positive relationships between moving and early initiation of illicit drugs including marijuana, hallucinogens, crack/cocaine, and illicit use of prescribed drugs. Among marijuana users, moving was also associated with a hastening of time to marijuana-related problems. Relationships between moving and measures of alcohol use/problems (onset of first drink, onset of any alcohol-related problem) were either weak or nonsignificant. Important sex differences were found, with statistically significant relationships between moving and early drug use initiation and progression occurring primarily among males. Future research is required to test for possible mediating mechanisms linking relocation with drug use as well as moderating influences. Efforts should also focus on finding out why drug use appears to be a more common response to relocation among boys.

In vivo role of endothelin-converting enzyme-1 as examined by adenovirus-mediated overexpression in rats.

We previously reported that adenovirus-mediated overexpression of endothelin-1 (ET-1) elevates systemic blood pressure in rats. In this model, plasma big ET-1: ET-1 ratios were almost 30, whereas they were only 5 in the control group, suggesting that endothelin-converting enzyme (ECE) may be a rate-limiting step in the production of ET-1 under these conditions. To further investigate the role of ECE in vivo, we prepared recombinant adenovirus strains carrying a soluble, secretory form of bovine ECE-1 cDNA (Ad.CMV. secECE), human ET-1 cDNA (Ad.CMV.ET-1), and, as a control, E. coli lacZ (Ad.CMV.beta-gal). Ad.CMV.secECE (1-10 x 10(9) pfu/ml) was injected into the caudal vein of male Wistar rats and the animals were studied 96 h later. Immunoblot analysis of circulating plasma confirmed the expression of the soluble ECE-1. The plasma levels of big ET-1 and mature ET-1 were similar in Ad.CMV.secECE and Ad.CMV.beta-gal groups (0.3-0.5 pM). When Ad.CMV.secECE was co-injected with Ad.CMV.ET-1 (2.5 x 10(9) pfu/ml each), plasma ET-1 levels were significantly elevated compared to the control group co-injected with Ad.CMV.secECE and Ad.CMV.beta-gal (10.2 +/- 2.4 vs. 1.1 +/- 0.2 pM). Big ET-1 levels were threefold higher (3.7 +/- 1.1 vs. 1.2 +/- 0.4 pM), and systemic blood pressure was significantly elevated (132 +/- 3 vs. 90 +/- 3 mm Hg) in the Ad.CMV.secECE + Ad.CMV.ET-1 group. Administration of an ECE inhibitor (CGS 26303, 30 mg/kg) significantly reduced the blood pressure in the Ad.CMV.secECE + Ad.CMV.ET-1 group (from 125 +/- 5 to 74 +/- 6 mm Hg) but not in the control group (from 85 +/- 2 to 75 +/- 3 mm Hg). Infusion of an ETA antagonist (FR 139317; 0.2 mg/kg/min for 30 min) also significantly reduced the blood pressure only in the Ad.CMV.secECE + Ad.CMV.ET-1 group, without any significant effect in the control group. This study demonstrates that even though overexpression of ECE-1 in itself does not lead to systemic hypertension, the enzyme can be a crucial rate-limiting factor in the production of mature ET-1 in vivo. Furthermore, this model may prove to be useful for in vivo screening of ECE inhibitors.

Pharmacology of endothelins in vascular circuits of normal or heterozygous endothelin-A or endothelin-B knockout transgenic mice.

Endothelin-1 (ET-1; 0.001-1 nmol) and the ETB receptor agonist IRL-1620 (0.01-1 nmol) induced a dose-dependent vasoconstriction of the arterial and venous mesenteric circuits and of the kidney in normal mice. BQ-123 (10(-7) M) or BQ-788 (10(-7) M) abolished the vasoconstriction induced by ET-1 in the arterial mesenteric and renal vasculatures without affecting that of norepinephrine (NE). In the venous mesenteric vasculature, only BQ-123 reduced the response to ET-1 but not to NE. In other experiments we compared the mesenteric and renal vascular reactivities to ET-1 and IRL-1620 in ETA or ETB heterozygous knockout mice with those of the wild-type strain. We observed a significant reduction in vascular reactivity to ET-1 but not to IRL-1620 in the arterial mesenteric and renal but not the venous mesenteric circuits of ETA knockout mice. In contrast, there was a significant reduction in vascular reactivity to ET-1 and IRL-1620 in the arterial mesenteric and renal circuits of ETB knockout mice. In the venous mesenteric vasculature, only the vasoconstriction induced by IRL-1620 was significantly reduced in the same ETB knockout strain. Our results suggest that, in the mouse, arterial mesenteric and renal vasoconstriction to ET-1 is mediated by both subtypes of ET receptors, whereas venous mesenteric vasoconstriction appears to be mediated uniquely by the ETA receptor subtype. Knockout of only one allele of the ETA or ETB gene appears to be sufficient for reduction of the ET-1 or IRL-1620 vasoconstrictor effects in the mesenteric and renal vascular beds of the mouse.

Prevalence and factors associated with physical and sexual assault of female university students in Ontario.

The authors examined the prevalence of physical and sexual assault of female university students and associated factors. In a survey of a random sample of 3,642 female students from 6 universities across Ontario, 24% of female students reported being physically assaulted and 15% reported being sexually assaulted during the previous year. When the assault measures were combined, 32% of university women reported being either physically or sexually assaulted during the previous year. Of those experiencing assault, 40% had been the victim of 2 or more types of assaults. Logistic regression analysis revealed that assault was associated with year of study, marital status, alcohol consumption, illicit drug use, prescription drug use, unhealthy eating and stress behaviors, less time spent on academics, and more time involved in social activities. University programs and activities directed toward the reduction of assault should incorporate the factors identified in this study to increase awareness of the situational factors surrounding likelihood of assault.

Predictors of the prevalence of alcohol use and related problems among Francophones and Anglophones in the province of Ontario, Canada.

OBJECTIVE: The aim of this study is to investigate Francophone/Anglophone differences in alcohol use/problems and associated risk factors in the province of Ontario, Canada. METHOD: Estimates are derived from a subsample of 1,127 Francophones and 4,023 Anglophones who completed the self-administered portion of the 1990 Ontario Health Survey, a random probability survey of over 60,000 Ontario residents. RESULTS: Results show that Francophones differ little from Anglophones on a variety of alcohol-related indicators including quantity and frequency of consumption, alcohol-related problems and driving while impaired. However, major differences between both groups are found in terms of the correlates and predictors of use and related problems. Among Francophones, subgroups at greatest risk of developing serious problems are those in the age group 55 to 64, professionals, and members of clubs and organizations. It is of interest that Francophone women arejust as likely as men to report problems related to their drinking and to drive while impaired. Among Anglophones, subgroups at greatest risk of developing problems are men, those age 45 to 54, those reporting their health status as fair or poor, those reporting suicidal thoughts and the sexually active. CONCLUSION: Specific subgroups within Ontario's Francophone population are at risk of serious problems related to their drinking and therefore may be in need of specialized prevention and treatment services.

Patterns of onset and cessation of drug use over the early part of the life course.

This study uses retrospective drug use histories to examine the timing of drug use behavior among young people participating in a large random probability survey of residents of the province of Ontario, Canada. Results reveal that the major risk period for initiation into alcohol, tobacco, and most illicit drugs begins around age 12 and is mostly over by age 22. For most drugs, peak periods of risk of initiation occur in the age range 15 to 19. For all categories of illicit drugs, results reveal high quit rates in the first few years of use followed by a sharp decline. Differences by gender reveal higher rates of onset for males for most drugs. Male drug users are significantly less likely than female users to quit using a drug. Results are discussed in terms of their implications for the development of primary prevention and early intervention programs for adolescents and young adults.