Portrait épidémiologique de la Ciguatera dans le Pacifique-sud

La ciguatera est une intoxication consécutive à l’ingestion de poissons d’ambiance corallienne contaminés par une micro-algue. Malgré une connaissance séculaire, l’apparente recrudescence de cette maladie, sa répartition géographique, sa variabilité symptomatique sont autant de points qui restent à éclaircir. Ce projet avait pour objectif de dresser le portrait épidémiologique actuel de cet ichtyosarcotoxisme en Polynésie Française afin d’en améliorer la prise en charge. Nos résultats démontrent que l’incidence de la ciguatera dans cette région est relativement stable. Parmi les facteurs écologiques associés aux variations d’incidence, la modélisation de la floraison de l’algue apparaît par nos analyses comme une avenue prometteuse d’une mise en place d’outils de prévention pour réduire l’incidence. Du point de vue clinique, nos résultats confirment la prédominance des symptômes neurologiques qui évoque une polyneuropathie sensitive se résorbant progressivement dont la gravité paraît reliée à la quantité de toxines ingérées.Ciguatera poisoning is an ichtyosarcotoxism found throughout many tropical areas of the world. Even though this intoxication has been known since the 18th century, many epidemiological aspects remain unclear. The main goal of this thesis was to establish the epidemiological portrait of this seafood poisoning in order to improve its management. The first part of this project describes this ichtyosarcotoxism according to its environmental and temporal aspects. The second part addresses clinical aspects of the disease. A global increase of ciguatera incidence has been suggested in the literature. However, results from our retrospective study indicate a relatively constant annual incidence in French Polynesia over the ten years of the study. An analysis of cases grouped by archipelago also revealed differences in incidence rates with the most remote archipelagos having the highest incidence. These high rates observed highlight the need to develop prevention tools in order to reduce the incidence. Results from our model of changes in the incidence of ciguatera disease following algae blooms might be useful for assisting ciguatera risk management initiatives. Indeed, results from the study highlight a clear temporal relation between ciguatera disease and its etiologic agent: Gambierdiscus spp. From a clinical point of view, our results confirm the neurological feature of this intoxication as previously proposed and suggest that several symptoms observed in 183 patients at the acute phase of the disease are still persistent 2 months after the onset. In order to characterize these symptoms, we compared the neurological evaluation of 47 patients with ciguatera disease to 125 ciguatera-free controls. Results showed that ciguatera disease predominantly alters the peripheral sensory system represented mainly by sensory disturbances (light-touch and thermal) and poorer sway performances compared to controls. Over three testing periods, we observed an improvement of sway performances but, light touch threshold remained altered for more than 50% of patient 60 days after of the onset. In summary, results obtained in this thesis confirm the evolution ciguatera disease to chronic stage in the study population and suggest that ciguatera symptoms in acute phase are similar to a sensory polyneuropathy with a progressive recovery

Acylation stimulating protein is higher in Inuit from Nunavik compared to a southern Quebec population

Objectives. The Inuit of Nunavik in northern Quebec have a lower risk for ischemic heart disease (IHD) compared to Caucasian populations. Acylation stimulating protein (ASP), which is involved in the storage of dietary fat, may play a role. The objective of the study was to determine plasma concentration of ASP in an Inuit and a southern Quebec Caucasian population. Study design. This is a cross-sectional study evaluating the relationship between ASP and dietary factors, such as retinol, whose intake is higher in the Inuit. As well, concentrations of ASP were evaluated in relationship to components of the metabolic syndrome. Methods. Medical history was collected via a questionnaire and anthropometric measurements and blood samples were collected. Results. ASP was significantly higher in both the Inuit men and women compared to Caucasian men (66.1±4.1 nM vs 27.5±2.5 nM, p<0.0001) and women (71.8±3.8 nM vs 29.4±1.3 nM, p<0.0001). In addition, ASP significantly correlated with total retinol (r=0.17, p=0.02) and free retinol (r=0.15, p=0.04) in Inuit men but not with other distinctive dietary markers such as omega3 fatty acids. Conclusions. Inuit men and women have higher ASP which was unrelated to the number of risk factors for IHD that were present

Omega-3 fatty acids, polymorphisms and lipid related cardiovascular disease risk factors in the Inuit population

Background : Tissue concentrations of fatty acids (FAs) and genetic variations are well-known factors which affect the cardiovascular disease (CVD) risk. The objective was to examine whether the genetic variability of 20 candidate genes and red blood cells (RBCs) percentage of total n-3 polyunsaturated fatty acids (PUFA), a biomarker of dietary n-3 PUFA intake, modulate lipid related CVD risk factors in the Inuit population. Methods : Data from the Qanuippitaa Nunavik Health Survey (n = 553) were analysed via multivariate regression models with 40 known polymorphisms, RBCs percentage of n-3 PUFA, and the interaction term to take into account the effect on plasma lipid and apolipoporotein levels. Results : Individuals being heterozygotes for CETP C-4502T (rs183130) or G-971A (rs4783961) together with higher n-3 PUFA had lower triacylglycerol (TG) concentrations compared to homozygotes for the minor allele. Further, effects of a stronger beneficial association between n-3 PUFA in RBCs and plasma lipid parameters- including lower total cholesterol (TC), lower low-density lipoprotein cholesterol (LDL-C) or higher high-density lipoprotein cholesterol (HDL-C) concentrations- were associated with AGT M235T (rs699) TT genotype, CETP G-971A (rs4783961) AG genotype, T allele carriers of CETP C-4502T (rs183130), and T allele carriers of CETP Ile405Val (rs5882). In contrast, higher n-3 PUFA in RBCs were associated with adverse lipid profiles- including increased LDL-C, increased apolipoprotein B100 or decreased HDL-C concentrations- in G allele carriers of the APOA5 -3 A/G (rs651821), C allele carriers of APOA5 T-1131C (rs662799), G carriers of APOC3 SstI (rs5128) and G carriers of APOA4 Asn147Ser (rs5104). Conclusion : Overall, these results suggest that percentage of total n-3 PUFA of RBCs are associated with lipids related CVD risk factors conferred by genetic variations in the Inuit population

Les toxines marines : problèmes de santé en émergence

Introduction  De nombreuses populations à travers le monde dépendent de l’environnement marin.  On estime à 60 % la proportion de la population mondiale qui vit le long des zones côtières; la plupart d’entre-elles dépendent de la mer pour assurer leur survie (National Research et al., 1999).  Cette relation intime qu’entretiennent les humains avec l’océan est particulièrement forte dans les régions méridionales telles que la région des Caraïbes.  Le tourisme et l’industrie de la pêche représe..

Effect of adapted karate training on quality of life and body balance in 50-year-old men

Marie-Ludivine Chateau-Degat1, G&amp;eacute;rard Papouin2, Philippe Saint-Val3, Antonio Lopez21Axe sante des populations et environmentale, CHUQ, Laval University, Quebec, Canada; 2Service de Cardiologie, Centre Hospitalier Territorial du Taone, 3F&amp;eacute;d&amp;eacute;ration Tahitienne de Karat&amp;eacute;, Papeete, French PolynesiaBackground: Aging is associated with a decrease in physical skills, sometimes accompanied by a change in quality of life (QOL). Long-term martial arts practice has been proposed as an avenue to counter these deleterious effects. The general purpose of this pilot study was to identify the effects of an adapted karate training program on QOL, depression, and motor skills in 50-year-old men.Methods and design: Fifteen 50-year-old men were enrolled in a one-year prospective experiment. Participants practiced adapted karate training for 90 minutes three times a week. Testing sessions, involving completion of the MOS 36-item Short Form Health Survey (SF36) and Beck Depression Inventory, as well as motor and effort evaluation, were done at baseline, and six and 12 months.Results: Compared with baseline, participants had better Beck Depression Inventory scores after one year of karate training (P &amp;lt; 0.01) and better perception of their physical health (P &amp;lt; 0.01), but not on the mental dimension (P &amp;lt; 0.49). They also improved their reaction time scores for the nondominant hand and sway parameters in the eyes-closed position (P &amp;lt; 0.01).Conclusion: Regular long-term karate practice had favorable effects on mood, perception of physical health confirmed by better postural control, and improved performance on objective physical testing. Adapted karate training would be an interesting option for maintaining physical activity in aging.Keywords: karate, balance, training, sport, agin

Population-based study of high plasma C-reactive protein concentrations among the Inuit of Nunavik

Background . The shift away from traditional lifestyle in the Inuit population over the past few decades has been associated with an increased prevalence of coronary heart disease (CHD) risk factors such as obesity, high blood pressure (BP) and diabetes. However, the impact of this transition on the pro-inflammatory marker high-sensitivity C-reactive protein (hs-CRP) has not been documented. Objectives . To examine the prevalence of elevated plasma hs-CRP concentrations in Inuit from Nunavik in the province of Quebec (Canada) and identify anthropometric, biochemical and lifestyle risk factors associated with elevated hs-CRP. Design . A population-representative sample of 801 Inuit residents from 14 villages of Nunavik, aged between 18 and 74 years, was included in the analyses. Subjects participated in a clinical session and completed questionnaires on lifestyle. Multivariate logistic regression was used to determine risk factors for elevated hs-CRP. Results . Elevated plasma hs-CRP concentrations (&#x2265;2 mg/L) were present in 32.7% (95% confidence interval (CI) 29.5&#x2013;35.8) of the Inuit adult population and were more prevalent among women than among men (36.7% vs. 29.0%, p=0.007). Multivariate logistic regression analysis indicated that every 1 mmHg increase in systolic BP was associated with a 3% increase in the odds of having hs-CRP concentrations &#x2265;2 mg/L in the Inuit population (95% CI 1.01&#x2013;1.04). The combination of older age (&#x2265;50 vs. &#60;30 years) and elevated waist circumference (gender-specific cut-off values) in a multivariate logistic model was also associated with a 13.3-fold increase in the odds of having plasma hs-CRP concentrations &#x2265;2 mg/L (95% CI 5.8&#x2013;30.9). Conclusions . These data indicate that elevated hs-CRP is relatively prevalent among Inuit with values that are similar to those seen in Canadian Caucasian populations. Sex, age, waist circumference and systolic BP are major factors that increase the risk of this inflammatory phenotype among Inuit from Nunavik, despite their different lifestyle background compared with Caucasians

Gene-diet interactions on plasma lipid levels in the Inuit population

The Inuit population is often described as being protected against CVD due to their traditional dietary patterns and their unique genetic background. The objective of the present study was to examine gene–diet interaction effects on plasma lipid levels in the Inuit population. Data from the Qanuippitaa Nunavik Health Survey (n 553) were analysed via regression models which included the following: genotypes for thirty-five known polymorphisms (SNP) from twenty genes related to lipid metabolism; dietary fat intake including total fat (TotFat) and saturated fat (SatFat) estimated from a FFQ; plasma lipid levels, namely total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C) and TAG. The results demonstrate that allele frequencies were different in the Inuit population compared with the Caucasian population. Further, seven SNP (APOA1 − 75G/A (rs670), APOB XbAI (rs693), AGT M235T (rs699), LIPC 480C/T (rs1800588), APOA1 84T/C (rs5070), PPARG2 − 618C/G (rs10865710) and APOE 219G/T (rs405509)) in interaction with TotFat and SatFat were significantly associated with one or two plasma lipid parameters. Another four SNP (APOC3 3238C>G (rs5128), CETP I405V (rs5882), CYP1A1 A4889G (rs1048943) and ABCA1 Arg219Lys (rs2230806)) in interaction with either TotFat or SatFat intake were significantly associated with one plasma lipid variable. Further, an additive effect of these SNP in interaction with TotFat or SatFat intake was significantly associated with higher TC, LDL-C or TAG levels, as well as with lower HDL-C levels. In conclusion, the present study supports the notion that gene–diet interactions play an important role in modifying plasma lipid levels in the Inuit population