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R Boyer

Publications and source records attributed to R Boyer.

At least 37 records · Page 2Linked to original sources
PubMed1998

Lifetime exposure to traumatic events among a sample of city bus drivers.

Lifetime exposure to traumatic events was assessed retrospectively among a representative sample of city bus drivers (228 men and 54 women) from Montréal, Canada. Among them, 68.1% reported at least one exposure to a traumatic event of any type. Among the 68% exposed. 70.4% reported multiple traumatic exposures (M = 2.6, SD = 1.67), with ratings ranging from 0 to 12. This report underlines the fact that the prevalence of traumatic events is not yet well known. Epidemiological research should devote more effort to assess fully the lifetime prevalence of traumatic events and not only cases of PTSD.

Adult↗
PubMed1998

Psychological distress and use of ambulatory medical services in the Quebec Medicare system.

OBJECTIVE: To document the impact of psychological distress symptoms on the use of ambulatory medical services in a universal insurance coverage context. DATA SOURCES: Data from the Quebec Health Survey (1987) linked with billing data from the Quebec Medicare system. The time frame for the utilization variables is one year before and one year after the QHS survey. STUDY DESIGN: LISREL was used to test a model introducing perceived health need as an explanatory factor of the relationship between psychological distress and the number of visits to a physician. Two samples were formed from the matched file. Sample A (n = 2,000) was used in an exploratory phase to adequately specify the model. Sample B (n = 2,000) was used to confirm the results obtained with Sample A. PRINCIPAL FINDINGS: The proposed model explained 35 percent of the number of visits to a physician in Sample A and 24 percent in Sample B. The effect of psychological distress symptoms on the respondent's perceived health need was as important as the effect of physical health status. The effect of the respondent's previous health services utilization on the number of visits to a physician was also significant. CONCLUSIONS: These results may be interpreted to indicate that in a universal insurance coverage context, psychological distress is a significant predictor of perceived health need.

Adolescent↗
PubMed1997

Mutation in the alpha-synuclein gene identified in families with Parkinson's disease.

Parkinson's disease (PD) is a common neurodegenerative disorder with a lifetime incidence of approximately 2 percent. A pattern of familial aggregation has been documented for the disorder, and it was recently reported that a PD susceptibility gene in a large Italian kindred is located on the long arm of human chromosome 4. A mutation was identified in the alpha-synuclein gene, which codes for a presynaptic protein thought to be involved in neuronal plasticity, in the Italian kindred and in three unrelated families of Greek origin with autosomal dominant inheritance for the PD phenotype. This finding of a specific molecular alteration associated with PD will facilitate the detailed understanding of the pathophysiology of the disorder.

Age of Onset↗
PubMed1997

Displaying electroencephalographic dipole sources on magnetic resonance images.

A simple, inexpensive method of displaying electroencephalographic (EEG) dipole sources on magnetic resonance images (MRIs) is presented. It consists of measuring the head according to the 10-20 system but instead of placing electrodes, benzonatate capsules (Tessalon Perles) (100 mg) are affixed to the patient's scalp. MRI is obtained with the capsules in place. In addition to the routine images, thin-section (1.0-1.3-mm) scans in a three-dimensional volume are obtained and the coordinates for each electrode position ascertained. The capsules are then replaced by electrodes and a waking and sleep recording is performed with a digital EEG instrument. Phenomena of interest are then averaged and interfaced with a source analysis program. The three-dimensional electrode coordinates are placed in a file and used to establish the electrode cloud on the basis of which source analysis proceeds. The three-dimensional source locations are then superimposed on the MRIs. The method is useful in the workup of epilepsy patients, by relating focal epileptogenic activity to definable lesions, and it also allows more precise localization of normal EEG phenomena.

Adolescent↗
PubMed1997

Use of health services for anxiety disorders: a multisite study in Quebec.

OBJECTIVE: We investigated patient characteristics and use of services for anxiety disorders among patients seeking care from participating clinicians at 7 anxiety clinics in Quebec: 3 general hospital clinics, 3 psychologist-run clinics, and one psychiatric hospital clinic. METHODS: Persons eligible for the study were those who were visiting the clinics for the first time, had a current diagnosis of an anxiety disorder, and could communicate in French or English. Subjects recruited through advertisements were excluded. Data, collected by a self-administered questionnaire, included demographics, treatment history, use of services for anxiety, and the Beck Anxiety Inventory (BAI). RESULTS: The sample comprised 235 subjects: 146 seen at 3 general hospital clinics, 54 at 3 psychologist-run clinics, and 35 at a psychiatric hospital clinic. There were statistically significant differences by clinic type in the prevalence of specific anxiety diagnoses, BAI score, referral source, antidepressant use, and use of services. High-intensity use (10 or more consultations during the previous year) was reported by 23.4% of the sample for medical services and 19.6% for mental health services. Multiple logistic regression identified variables associated with high-intensity use of medical services (higher BAI score, 1 to 4 years since first sought treatment, and less than 12 years of education) and high-intensity use of mental health services (clinic type, obsessive-compulsive disorder [OCD], and 5 or more years since first sought treatment). CONCLUSIONS: The patient populations seen at different types of anxiety clinics differ in several respects, including referral source, previous treatment, and severity of symptoms. Regardless of type of clinic, patients with a longer time since they first sought treatment use more services, particularly mental health services. Those with less education use more medical services than those with greater education.

Adult↗
PubMed1997

Involvement of the pontomedullary corticospinal tracts: a useful finding in the diagnosis of X-linked adrenoleukodystrophy.

PURPOSE: To determine whether pontomedullary corticospinal tract involvement is a common and specific finding of adrenoleukodystrophy on MR images. METHODS: MR images of 10 patients with biochemically proved adrenoleukodystrophy who were examined during the last 6 years were reviewed retrospectively to determine the frequency of corticospinal tract involvement in the medulla, pons, mesencephalon, internal capsules, and corona radiata. MR images of 10 patients with other leukodystrophies (three with Krabbe disease, two with Alexander disease, two with metachromatic leukodystrophy, two with Pelizaeus-Merzbacher disease, and one with Canavan disease) were reviewed with specific attention to the pontomedullary corticospinal tracts. RESULTS: Medullary and pontine corticospinal tract involvement was present in eight of the 10 patients with adrenoleukodystrophy. Mesencephalic and internal capsular involvement was present in three patients. The coronal radiata portion of the corticospinal tracts was not involved in any of the 10 patients. No pontomedullary corticospinal tract involvement was identified in any of the 10 patients with other leukodystrophies. The difference in the frequency of pontomedullary corticospinal tract involvement between the two groups was highly significant. CONCLUSION: Pontomedullary corticospinal tract involvement is a common finding in adrenoleukodystrophy and is unusual in other leukodystrophies. Awareness of this finding can facilitate the radiologic diagnosis of this disease and may expedite management of affected patients.

Child↗
PubMed1996

A phase II trial of docetaxel in advanced non-small cell lung cancer.

Twenty-nine patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) were treated with docetaxel. Ten patients had already received chemotherapy, the others had received no chemotherapy. Docetaxel was administrated i.v. over 60 min every 21 days at a dose of 100 mg/m2. Twenty-three patients were evaluable for response. There were no complete responses and eight partial responses. The overall response rate was 35% (28% in the intent to treat analysis). Median duration of response was 43 weeks and median time to progression 12 weeks. Neutropenic infections, neurotoxicity and asthenia were dose-limiting toxicities (6% of 118 cycles). The other main toxicities were asthenia in 48%, skin reactions in 31% and nail changes in 31% of the patients. Single-agent docetaxel appears to be active against both previously treated and untreated advanced NSCLC. Toxicity was acceptable but should be carefully monitored.

Adult↗
PubMed1996

Social desirability in the assessment of trauma.

Since admitting distress is often considered undesirable, the role of social desirability as a moderator variable in the assessment of traumatic events scores, on the PTSD Interview, and diagnosis was investigated. A sample of 342 city bus drivers were grouped by their lifetime exposure to trauma (nonexposed, stressful but nontraumatic event, traumatic event). Analyses replicate and extend findings from the literature on life events: social desirability plays a marginal role as a moderator variable in the assessment of trauma.

Bias↗
PubMed1996

[Prevalence of post-traumatic stress disorder in bus drivers].

Many recent reports indicate that public transport employees constitute a group of workers at high risk of going through a traumatic event. Yet, very few scientific data on the impact of these events on this population are available. The authors present results of an epidemiological study conducted among Montreal bus drivers. A little more than a third of bus drivers have reported a traumatic event at work. Among the whole of traumatic events occurring during the course of their work, serious threats and assault constitute the majority of these events. Traumatic events are more frequent at work than in their private lives. The prevalence of PTSD for those exposed to a traumatic event at work is of 10.7% and of 21.3% for those bus drivers exposed to traumatic events in their private lives. Nine out of 100 drivers exposed to a traumatic event at work suffered a PTSD in the month preceding the study. When the authors consider the events occurring in the private lives, almost 15% of those exposed were victims of PTSD. When the two levels of expositions are reunited, 12% of those exposed presented a PTSD in the month preceding the research.

Adult↗
PubMed1996

HIV seropositive gay men: understanding adoption of safe sexual practices.

The aim of this study was to determine the best predictors of safe sex practices among HIV seropositive gay men. A group of 96 homosexual men living with HIV completed a questionnaire that investigated theoretical constructs of the Ajzen's (1988) theory of planned behavior with respect to condom use for anal intercourse and sexual practices without anal intercourse. Other variables such as Triandis's (1977) construct of personal normative belief, psychological distress, and alcohol and drug use before sexual encounters were also investigated. Results indicated that the best predictor of intention to use condoms was perceived behavioral control. Personal normative belief was another important predictor of this intention. Although the best predictor of intention to have only sex without anal intercourse was perceived subjective norm, this intention was also significantly explained by perceived behavioral control. Moreover, perceived behavioral control was a significant predictor of having only sex without anal intercourse. Public health interventions among HIV seropositive gay men should aim mainly at increasing perception of behavioral control.

Adult↗
PubMed1996

[Suicide prevention by preventing mental disorders: how far did we get in Quebec?].

The relationship between mental illness and suicide no longer has to be demonstrated. In Quebec however, those intervening in the prevention of suicide, without denying this link, appear not to have integrated this information in their practice. As in North America and Europe, very few prevention centres have evaluated the efficiency and impact of their intervention. Finally, the few programs promoting mental health or preventing mental illness elaborated in Quebec seldom aim at preventing suicide. In these conditions how can we expect reducing the suicide rate?

Humans↗
PubMed1995

The need for water quality criteria for frogs.

Amphibians are considered reliable indicators of environmental quality. In the western United States, a general decline of frog populations parallels an apparent worldwide decline. The factors thought to be contributing to declines in frog populations include habitat loss, introduction of exotic species, overexploitation, disease, climate change, and decreasing water quality. With respect to water quality, agroecosystems use 80-90% of the water resources in the western United States, frequently resulting in highly eutrophic conditions. Recent investigations suggest that these eutrophic conditions (elevated pH, water temperature, and un-ionized ammonia) may be associated with frog embryo mortality or malformations. However, water quality criteria for frogs and other amphibians do not currently exist. Here, we briefly review data that support the need to develop water quality parameters for frogs in agroecosystems and other habitats.

Abnormalities, Drug-Induced↗
PubMed1995

The structure of psychological distress.

In this study we describe the factor structure of the Psychological Distress Index used in the Quebec Health Survey and compare a model that includes psychophysiologic symptoms (29 items) with a model restricted to cognitive and affective symptoms only (18 items). Three samples (n = 2,000) were used to test the likelihood of these two models. Confirmatory factor analyses were carried out using LISREL VII. Logistic regression was then used to examine the association of the two versions with demographic variables and health indicators. Analysis indicates that both versions show satisfactory construct validity. Except for age, the associations observed between both versions and respondents' demographic characteristics are similar; however, the 29-item version is more strongly associated with health status indexes, suggesting a possible bias attributable to somatic items.

Adolescent↗
PubMed1994

Suicide and mental disorders: a case-control study of young men.

OBJECTIVE: By means of the psychological autopsy method and a case-control design, the authors examined the association of specific mental disorders and comorbidity with suicide among young men. METHOD: Seventy-five men aged 18-35 years whose deaths were adjudicated as completed suicides by coroners of greater Montreal and Quebec City were matched to 75 living young men for age, neighborhood, marital status, and occupation. For each subject in both groups a key respondent best acquainted with the subject was interviewed by clinicians using standardized schedules. Information from the coroner and medical records was also collected. Two experienced psychiatrists, blind to outcome, established best-estimate DSM-III-R diagnoses. RESULTS: Six-month prevalence rates for all axis I diagnoses for the suicide and comparison groups were 88.0% and 37.3%, respectively; major depression was present in 38.7% and 5.3%, alcohol dependence in 24.0% and 5.3%, psychoactive substance dependence in 22.7% and 2.7%. Borderline personality disorder was identified in 28.0% and 4.0%, respectively. Of the suicide subjects, 28.0% had at least two of the following disorders: major depression, borderline personality disorder, and alcohol or drug dependence; the rate was 0.0% among the comparison subjects. CONCLUSIONS: In young men, completed suicide is linked to specific mental disorders, namely, major depression, borderline personality disorder, and substance abuse. Comorbidity involving any of these disorders is frequently associated with completed suicide.

Adolescent↗
PubMed1994

[Suicide among young male adults in Quebec: psychopathology and utilization of medical services].

Seventy five young male adults between the age of 18 and 35 who had committed suicide were compared with 75 male adults still alive matched for age, residence, marital and employment status. For each group a principal respondent was interviewed in order to reconstitute the psychological profile of each individual, as well as their utilisation of health services. This was completed by the study of the coroner's reports and the medical records when available. At six months the prevalence for all axis I diagnosis was 88.8% for the suicide group and 37.3% for the control group. Among the subjects who had committed suicide 38.7% were afflicted by major depression, 24% by alcohol dependency and 28.7% were dependent on drugs. Borderline personalities were present in 28% of the suicide group compared to 5% in the control group. Forty five percent (45%) of the subjects who had killed themselves had consulted a mental health professional in the year preceding the suicide compared to 5% in the control group. However, 78.5% of the suicide group had consulted during the same period a health professional compared to 73.3% of the controls.

Adolescent↗
PubMed1993

Frequency of sexually transmitted diseases among university students.

OBJECTIVE: To estimate the incidence rate of sexually transmitted diseases (STDs) among university students and evaluate the associated sociodemographic factors. DESIGN: Mail survey in April 1990. Included in the questionnaire were questions about the subjects' STD experience since their admission to the university and the type and date of the infection. SUBJECTS: Of the 19,682 undergraduate students 2920 subjects, in 10 groups of 292, were randomly selected. A total of 1731 (59.4%) completed the questionnaire. MAIN OUTCOME MEASURES: Estimated annualized incidence rates of genital human papillomavirus infection and Chlamydia infection. RESULTS: The estimated annualized incidence rates of genital human papillomavirus and Chlamydia infections were 2.2% and 1.5% respectively. Among the students who indicated being infected with genital human papillomavirus 59% were 18 to 21 years old (p < 0.05), 76% were women (p < 0.01) and 69% had more than one sexual partner (p < 0.01). No statistically significant associations were observed between age, sex and Chlamydia infection. On the other hand, 95% of the cases of Chlamydia infection were found among those who had more than one sexual partner (p < 0.01). CONCLUSION: University students continue to have sexual activities at risk for STDs and should be specifically targetted by general practitioners and health services in an effort to slow the spread of STDs.

Adolescent↗
PubMed1993

[Factors associated with at-risk anal relations in homosexual HIV-seropositive men].

This pilot study proposes an index to quantify the intensity of high-risk anal sex and presents factors associated with this practice among 65 homosexual men with HIV infection. All of them answered a self-administered questionnaire. Using multiple logistic regression, we first compared those who had had safe sex in the past six months to those who had had unsafe sex. Variables significantly associated with unsafe sex are: drugs and/or alcohol use with sex, and less favorable attitude towards condom use. Finally, multiple linear regression analysis among respondents who had had unsafe sex indicated that the following factors are associated with higher levels of unsafe sex: men between the ages of 32 and 38, satisfied with their social life, non-smokers, with a less favorable attitude towards condom use, and with few social relationships. These results must be interpreted with caution because of the small number of respondents.

Attitude↗