PubMed Health⌕ Search

Biomedical subjects

L Renaud

Publications and source records attributed to L Renaud.

At least 19 recordsLinked to original sources
PubMed2005

[Fight against tobacco and promote breastfeeding: a distinctive challenge].

Quebec's breastfeeding rates are in a deplorable state, and even more so for smoking mothers. Public health providers are trying to increase breastfeeding rates and decrease smoking in this specific target group. Should they prioritise tobacco cessation interventions, or breastfeeding promotion interventions, or give equal priority to both goals at the same time? The authors attempt to scientifically answer this question, through a comprehensive literature review over the last ten years. In general, women who smoke have the tendency be younger, be less educated and more underprivileged than mothers who do not smoke and to breastfeed less often. Smoking mothers who do breastfeed usually wean off breastfeeding earlier than those who do not smoke. Pregnancy is considered an ideal moment to stop smoking, but relapse after giving birth is very high. In light of the range of difficulties faced when trying to quit smoking, health professionals should encourage smoking mothers to breastfeed since the benefits of breastfeeding could actually serve to reduce some of the harmful effects related to tobacco. Nicotine patches can be prescribed to increase the chances for successful tobacco cessation amongst these mothers. To date, few studies have been carried out on nicotine replacement therapies and breastfeeding smokers. More research is needed to evaluate the risks and benefits of nicotine substitutes for this sub-group, in both the short and long term.

Adult↗
PubMed2004

[Heart health promotion and preventive practices of Quebec nurses working in local community health centers].

The heart health promotion and prevention practices of nurses working in front-line services in 20 Québec CLSC's are analyzed through a qualitative (n = 47 nurses) and a quantitative approach (n = 177 nurses and n = 3802 patients). The results demonstrate that although nurses state they integrate prevention and promotion in their daily practice, patients report that nurses provide few prevention recommendations. The major challenge for prevention-promotion is to strengthen secondary prevention and, especially, integrate primary prevention and promotion in nurses' daily clinical practice.

Community Health Nursing↗
PubMed2003

The St-Louis du Parc Heart Health Project: a critical analysis of the reverse effects on smoking.

OBJECTIVES: Although some school based smoking prevention programmes have shown positive impacts, others have had only short term effects, no effects, and in some cases reverse effects. The St-Louis du Parc Heart Health Project was a five year heart health promotion programme targeting children in eight elementary schools aged 9-12 years in disadvantaged multiethnic neighbourhoods in Montreal. In a controlled, longitudinal evaluation, the programme produced reverse effects on smoking--children exposed to the programme were more likely to initiate and to continue smoking than control children. This article explores hypotheses to explain the reverse effects. DESIGN: Following work by an in-house committee, a consensus workshop with international experts was conducted to develop hypotheses to explain the reverse effects. This was complemented by an analysis of the programme's concordance with the standard guidelines on the school based prevention of tobacco use, and discussions with experts at the Centers for Disease Control and Prevention. RESULTS: The programme respected most standard guidelines for smoking prevention programmes with respect to content and mode of delivery. Hypotheses to explain the reverse effects include: an unfavourable environment characterised by strong pro-smoking models and resistance to environmental interventions; heightened sensitivity to smoking among children most exposed to the programme; defence mechanisms among children stimulated by cognitive dissonance or anxiety; unanticipated effects associated with the health educator who delivered the programme; inadequate attention in programme development to the diverse cultural origins of the population targeted; and intervention content inappropriately targeted to children's stages of cognitive development. CONCLUSION: Elementary school based interventions should aim to develop a clear and coherent social norm about the non-use of tobacco, as a precursor to or in close conjunction with having children as their primary target. Programme design should take key student characteristics into consideration and ensure that the modes of communication are adapted to the targeted group's characteristics. Neighbourhood level interventions should be orchestrated to complement regional, provincial, and national programmes.

Child↗
PubMed2002

Neuronal response to local electrical stimulation in rat thalamus: physiological implications for mechanisms of deep brain stimulation.

High-frequency deep brain stimulation (DBS) of sensorimotor thalamus containing "tremor cells" leads to tremor arrest in humans with parkinsonian and essential tremor. To examine the possible underlying mechanism(s), we recorded in vitro intracellular responses of rat thalamic neurons to local intrathalamic stimulation. Such simulated DBS (sDBS) induced a sustained membrane depolarization accompanied by an increase in apparent membrane conductance in both motor and sensory neurons. With stimulation frequency above approximately 100 Hz, the sDBS-induced depolarization most typically led to repetitive neuronal firing or less frequently resulted in a complete blockade of action potential genesis. When regular intracellular current pulses were injected into cells to mimic "tremor" activity, such rhythmic discharges were invariably disrupted or abolished by the random spike firing induced during high-frequency sDBS. Low-frequency sDBS left rhythmicity unaffected.We conclude that clinical thalamic DBS may lead to a neuronal de-rhythmicity and tremor stoppage through masking and/or blocking rhythmic firing of tremor cells.

Action Potentials↗
PubMed2001

Evidence against a major role of plasmalogens in the resistance of astrocytes in lactic acid-induced oxidative stress in vitro.

Astrocytes are known to play a key role in buffering extracellular pH variations and, in addition, they are particularly resistant to oxidative stress and subsequent lipid peroxidation. This great resistance may be ascribed to the presence of high concentrations of certain antioxidants, but another explanation may be the presence of a high quantity of plasmalogens, which are a special group of glycerophospholipids characterized by a vinyl ether bond instead of an ester bond in the sn-1 position of the glycerol backbone. Plasmalogens are sensitive to free radical attack and acidity, and numerous works have supported the hypothesis that they may be antioxidant molecules that protect cells from oxidative stress. The aim of this work was to investigate, on astrocytes in lactic acid-induced oxidative stress (pH 5.5), the behavior of phospholipids and, in particular, plasmalogens. Two main techniques, based on the susceptibility of the vinyl ether bond to hydrolysis, were employed in this study to measure plasmalogen levels. In both cases, the sn-1 vinyl ether linkage was cleaved using mercuric chloride, producing a lysophospholipid that was assessed by phosphorus measurement or using HCl treatment, producing a long-chain fatty aldehyde assayed by gas chromatography/mass spectrometry. On astrocytes in culture, only plasmenylethanolamine (PlmEtn) was evidenced, representing 40% of glycerophosphoethanolamine lipids. When astrocytes were incubated with lactic acid, no modification in the amount of PlmEtn was seen. Furthermore, free aldehydes and aldehydes corresponding to the quantity of intact plasmalogens were similar to those observed on controls. In addition, the constancy of two lipid peroxidation markers, thiobarbituric acid reactive substances and polyunsaturated fatty acids, was clear evidence of the resistance of these cells in lactic acid conditions. In conclusion, our results fail to demonstrate a major role of plasmalogens in the resistance of astrocytes in lactic acid-induced oxidative stress.

Acidosis, Lactic↗
PubMed2001

Au coeur de la vie: the Quebec Heart Health Dissemination Project.

"Au coeur de la vie" is a research project which aims to evaluate the impact of a heart health dissemination program on primary and secondary prevention practices in local community clinics in the province of Quebec, Canada. Because the project starts in 2001 and no data has been collected to date this paper presents the theoretical model, the objectives of the program, the description of the dissemination procedures, and a brief overview of the evaluation.

Diffusion of Innovation↗
PubMed2000

Intervening to reduce weight gain in pregnancy and gestational diabetes mellitus in Cree communities: an evaluation.

BACKGROUND: A high prevalence of gestational diabetes mellitus and type 2 diabetes has been observed among the Cree of James Bay, Quebec. To address this problem, a diet and activity intervention during pregnancy, which was based on social learning theory, was initiated in 4 Cree communities. METHODS: A prospective intervention compared dietary, weight and glycemic indicators for 107 control subjects and for 112 women who received the intervention during the course of their pregnancy. A control period in 4 communities (July 1995-March 1996) was followed by an intervention period (April 1996-January 1997) when subjects were offered regular, individual diet counselling, physical activity sessions and other activities related to nutrition. RESULTS: The intervention and control groups did not differ at baseline regarding their mean age (24.3 years [SD 6.29] v. 23.8 years [SD 5.86]), mean prepregnancy weight (81.0 kg [SD 19.46] v. 78.9 kg [SD 17.54]) and mean gestational age at recruitment (17.1 weeks [SD 7.06] v. 18.5 weeks [SD 6.92]). The intervention did not result in differences in diet measured at 24-30 weeks' gestation, rate of weight gain over the second half of pregnancy (0.53 kg per week [SD 0.32] v. 0.53 kg per week [SD 0.27]) or plasma glucose level (50 g oral glucose screen) between 24 and 30 weeks (7.21 mmol/L [SD 2.09] v. 7.43 mmol/L [SD 2.10]). Mean birth weights were similar (3741 g [SD 523] v. 3686 g [SD 686]), as was maternal weight at 6 weeks post partum (88.1 kg [SD 16.8] v. 86.4 kg [SD 19.0]). The only changes in dietary intake were a reduction in caffeine (pregnancy) and an increase in folate (post partum). INTERPRETATION: This intervention had only a minor impact on diet; finding ways of encouraging appropriate body weight and activity levels remains a challenge.

Adult↗
PubMed1999

Prevalence and correlates of physical activity behaviors among elementary schoolchildren in multiethnic, low income, inner-city neighborhoods in Montreal, Canada.

PURPOSE: To describe the prevalence and correlates of physical inactivity and of participation in organized sports at and outside school among elementary schoolchildren in multiethnic, low income, urban neighborhoods in Montreal, Canada. METHODS: As part of the evaluation of a school-based heart health promotion program, baseline data on physical activity behaviors and potential correlates of these behaviors, were collected from 2285 students aged 9-13 in all 130 grade 4 to 6 classes in 24 inner-city elementary schools from May to June 1993. RESULTS: One-fifth of boys (20.5%) and 24.4% of girls were inactive; 40.0% and 33.3% of boys and girls respectively, participated in school sports teams; 82.5% and 74.7% participated in organized sports outside school. Declines in activity levels with age were apparent in both genders. Children who participated in organized sports programs at and outside school, those with higher perceived self-efficacy for physical activity, and those with more parental support for engaging in physical activity were more active. Children of Asian family origin were less active. Socioeconomic status was related to participation in organized sports outside school. CONCLUSIONS: To reach children in socio-economically disadvantaged areas and to prevent age-related declines in activity levels, interventions promoting physical activity should focus on increasing availability and access to community-based organized sports programs at and outside school. Also they should include components to increase parental support and to improve perceived self-efficacy for physical activity.

Adolescent↗
PubMed1999

The impact of a community-based heart disease prevention program in a low-income, inner-city neighborhood.

OBJECTIVES: This study evaluated the impact of a 4-year, community-based cardiovascular disease prevention program among adults aged 18 to 65 years living in St-Henri, a low-income, innercity neighborhood in Montreal, Quebec. METHODS: Awareness of and participation in the program were monitored in 3 independent sample telephone surveys. Self-reported behaviors were compared in St-Henri and a nearby comparison community before and after program implementation in both a 3-year repeat independent sample survey and a 5-year longitudinal cohort telephone survey. RESULTS: Awareness of the program reached 37.4%, but participation was low (2%-3%). There were no secular declines in smoking or high-fat diet; physical inactivity increased in both communities. There were no statistically significant program effects detected in the independent sample surveys, although physical inactivity increased more in the comparison community than in St-Henri. In the longitudinal cohort sample, there was a small, statistically significant increase favoring St-Henri in frequency of cholesterol checkups. CONCLUSIONS: Despite careful adaptation of the program to the local social context, there were few community-wide program effects. However, several component interventions showed promise in terms of community penetration and impact.

Adult↗
PubMed1998

Prevalence and correlates of early smoking among elementary schoolchildren in multiethnic, low-income inner-city neighborhoods.

PURPOSE: The prevalence and correlates of early smoking were investigated among schoolchildren in grades 4-6 living in multiethnic, low-income neighborhoods in Montreal. METHODS: As part of the evaluation of a school-based heart health promotion program, baseline data on the prevalence of early smoking were collected from 2285 students aged 9-13 years in 24 inner-city elementary schools during May-June 1993. RESULTS: Overall, 28.7% of boys and 20.3% of girls had smoked. Girls began trying later than boys, but by age 13 the prevalence of experimental or regular smoking by girls overtook that of boys. Univariately, ever smoking varied considerably by family origin, from 2.1% among Vietnamese girls, to 35.8% among Portuguese boys. In multivariate analysis, age, perceived smoking habits of friends, and smoking by family members, were strong correlates of smoking. Being of Asian family origin was negatively associated with smoking. None of the indicators of social class were significantly associated with ever smoking. CONCLUSIONS: Smoking prevention should begin with children even younger than age 9 in multiethnic, low-income, inner-city neighborhoods. With the exception of a lower prevalence of smoking among Asian children, ethnicity and social class were not strong influences on early smoking behavior in this population.

Adolescent↗
PubMed1998

Prevalence and correlates of overweight among elementary schoolchildren in multiethnic, low income, inner-city neighbourhoods in Montreal, Canada.

PURPOSE: Increased understanding of the early determinants of obesity is essential because of the increasing prevalence of obesity in many industrialized countries. METHOD: As part of the evaluation of a school-based heart health promotion intervention, we measured height, weight, and triceps skinfold thickness at baseline in 2108 students aged 9-12 years (80.5% of eligible students) in 24 inner-city elementary schools located in multiethnic, low income neighbourhoods in Montreal, Canada. Data on student's socio-demographic and lifestyle characteristics were collected in classroom-administered questionnaires, and parents completed an at-home self-administered questionnaire. RESULTS: Overall, 35.2% of boys and 33.0% of girls were overweight (> or = 85th age and gender-specific percentiles from NHANES 11, for body mass index and triceps skinfold thickness); 15.1% of boys and 13.3% of girls were obese (> or = 95th age and gender-specific percentiles for body mass index and triceps skinfold thickness). Younger age, having lived all one's life in Canada, and being of European or Central American/Caribbean family origin were independent correlates of obesity in boys. Younger age, ever smoked, mother obese and father obese were independent correlates of obesity in girls. Girls of Asian family origin were protected. CONCLUSIONS: The very high prevalence of overweight students in this low income, multiethnic population suggests an important need for preventive intervention.

Anthropometry↗
PubMed1998

One-year predictors of smoking initiation and of continued smoking among elementary schoolchildren in multiethnic, low-income, inner-city neighbourhoods.

OBJECTIVE: To identify one-year predictors of smoking initiation among never-smokers, and of continued smoking among ever-smokers. DESIGN: Two sequential cohorts of grade 4 and 5 children. Data were collected as part of Coeur en sante St Louis du Parc, a non-randomised controlled trial to evaluate the impact of a school-based heart health promotion programme. SETTING: 24 inner-city elementary schools located in multiethnic, low-income neighbourhoods in Montreal. SUBJECT: 1824 schoolchildren aged 9-12 years with baseline and one-year follow-up data. MAIN OUTCOME MEASURES: Changes in smoking behaviour over a year; the ability of baseline data to predict smoking initiation and continued smoking a year later was investigated in logistic regression analyses. RESULTS: The prevalence of ever-smoking was 21.1% at baseline and 30.2% at one-year follow up. One in six never-smokers initiated smoking; one in three ever-smokers continued smoking. Predictors of initiation included age (odds ratio (OR) = 1.6, 95% confidence interval (CI) = 1.3 to 2.0), male gender (OR = 1.5 (95% CI = 1.1 to 2.0)), friends who smoke (OR = 2.3 (95% CI = 1.7 to 3.3)), sibling(s) who smoke (OR = 1.9 (95% CI = 1.2 to 3.1)), father/mother who smokes (OR = 2.2 (95% CI = 1.6 to 3.0)), and frequent high fat/"junk food" consumption (OR = 1.6 (95% CI = 1.1 to 2.1)). Age and friends who smoke were also independent predictors of continued smoking in both genders. In addition, in boys, current smokers at baseline were 2.6 times (95% CI = 1.4 to 5.0) more likely to continue smoking than past smokers. In girls, being overweight was associated with continued smoking (OR = 3.5 (95% CI = 1.6 to 7.6)). CONCLUSIONS: Smoking prevention programmes should address parental and sibling influences on smoking, in addition to refusal skills training. Among girls, weight-related issues may also be important.

Age Factors↗
PubMed1998

Sputum eosinophilia is more closely associated with airway responsiveness to bradykinin than methacholine in asthma.

Hyperresponsiveness of the airways to various spasmogenic stimuli is a characteristic feature of bronchial asthma. However, the association between the different stimuli to which asthmatic airways are hyperresponsive and airways inflammation is not completely understood. We have investigated the relationship between airway inflammation and airway hyperresponsiveness in asthma, as assessed by bronchoprovocation tests to methacholine and bradykinin, two well defined bronchoconstrictor agonists. Sputum induction by hypertonic saline and methacholine and bradykinin challenges were performed in 14 nonsmoking subjects with mild-to-moderate asthma. Airway responsiveness to either agonist did not correlate with sputum neutrophils, lymphocytes, and macrophages. Whilst the absolute number of eosinophilia failed to be significantly related to methacholine responsiveness (r=-0.47; p=0.09), it correlated markedly and significantly with provocative concentration of methacholine causing a 20% fall in forced expiratory volume in one second (r=0.72; p<0.01). When expressed as % of total cell counts, sputum eosinophils correlated with both types of responsiveness (r=-056; p=0.04 and r=-0.76, p<0.001, respectively). Although the concentration of eosinophil cationic protein (ECP) in the sputum correlated with the absolute numbers of eosinophils (r=0.62; p<0.02), no correlation was found between ECP levels and the airway responsiveness to any of the agonists tested. In subjects with mild-to-moderate asthma, airway responsiveness to bradykinin is more strongly associated with the magnitude of eosinophilic inflammation in the airways than methacholine. This finding underlines the selectivity of diverse agonists in assessing airway hyperresponsiveness and cellular inflammation in asthma.

Adolescent↗
PubMed1998

[A cardiovascular health promotion program for 9-12 year old children and the community of Saint-Louis du Parc/Quebec].

This article presents a programme for cardiovascular health for 9 to 12 years old children, called "Healthy Heart" Saint-Louis du Parc and carried out in low socioeconomic and multiethnic part of Montreal, Quebec, Canada. These five years programme targets were more both spheres: school and community (leisure centre, ethnocultural centre, groceries and other places). We develop the objectives, the conceptual models underlying to the programme, the perspective of work, the infrastructure of the programme: its staff and financing, the partnerships and the structure organising. Then we present the various interventions carried out along the period and so a description of many evaluations. At last, we discuss about the programme continuation.

Cardiovascular Diseases↗
PubMed1997

Reliability of proxy reports of parental smoking by elementary schoolchildren.

PURPOSE: To investigate the reliability of reports of parental smoking by elementary schoolchildren aged 9-13 years, and to identify the correlates of disagreement between student proxy and parent self-reports. METHODS: As part of the evaluation of a school-based heart health promotion program, data on parental smoking status were collected from 1240 student-mother pairs and 898 student-father pairs. RESULTS: Agreement for parental smoking status was 93.1% among student-mother pairs and 86.4% among student-father pairs. Among student-mother pairs, reports by students aged 9 years were more likely to disagree with mothers' self-reports than those of older children (odds ratio (OR) = 3.1). Among student-father pairs, the only significant correlate of disagreement was living in a single-parent family headed by the mother (OR = 2.6). CONCLUSIONS: Children 10-years or older can provide reliable reports of the smoking status of cohabiting parents.

Adolescent↗
PubMed1997

The "Yes, I Quit" smoking cessation course: does it help women in a low income community quit?

The objectives were to evaluate the impact of "Yes, I Quit" (a smoking cessation course tailored for women in a low income, low education community), and to identify baseline predictors of short and longer-term self-reported cessation. The impact was evaluated in a before-after study design with no comparison group. Baseline data were collected in self-administered questionnaires at the beginning of the first session of the course. Follow-up data were collected in telephone interviews at one, three and six months after the designated Quit Day. Self-reported quit rates among 122 participants were 31.1%, 24.7% and 22.3% at one, three and six months. Non-quitters reduced their consumption by 10.3, 8.3, and 7.1 cigarettes per day at one, three and six months. Multivariate logistic regression analyses showed that being in excellent/good health was significantly associated with cessation at one month (odds ratio (OR) = 2.4). Being married (OR = 13.0) and no other smokers in the household (OR = 3.6) were associated with three-month cessation. Only being married was associated with six-month cessation (OR = 6.8). "Yes, I Quit" produced quit rates among low income, low education participants comparable to those reported for cessation programs directed at the general population of smokers. Good health is associated with early cessation, while support from a spouse is important to maintaining a non-smoking status among quitters.

Adolescent↗
PubMed1996

[Transition of the roles and mandates of public health professionals].

There is a call for a new intervention paradigm that integrates all dimensions of physical, political and economic environments that might impact on health. The Ottawa Charter, the Global Plan for Health Promotion and the Health and Welfare Policy to mention a few, suggest that public health agents broaden their roles and their mandates. From health educators, they are now being asked to not only continue to favour the development of personal skills, to help create supporting environments, to reorient health services, to reinforce community action, as well as elaborate health public policies but to also become consensus builders towards this new paradigm. This article discusses the transition of the role and mandate of the individual health professional. In order to do so, the article traces the practice of the health professional beginning at the end of the 1970's and compares it to that of 1996 looking at the following dimensions: roots, objectives, place of activity, favoured strategies and approaches. Furthermore, it will try to identify new obstacles in health promotion. Finally, it will underline the new challenges for public health near the year 2000.

Health Personnel↗