Lamine Gueye

Cholera outbreak in Senegal in 2005: was climate a factor?

Cholera is an acute diarrheal illness caused by Vibrio cholerae and occurs as widespread epidemics in Africa. In 2005, there were 31,719 cholera cases, with 458 deaths in the Republic of Senegal. We retrospectively investigated the climate origin of the devastating floods in mid-August 2005, in the Dakar Region of Senegal and the subsequent outbreak of cholera along with the pattern of cholera outbreaks in three other regions of that country. We compared rainfall patterns between 2002 and 2005 and the relationship between the sea surface temperature (SST) gradient in the tropical Atlantic Ocean and precipitation over Senegal for 2005. Results showed a specific pattern of rainfall throughout the Dakar region during August, 2005, and the associated rainfall anomaly coincided with an exacerbation of the cholera epidemic. Comparison of rainfall and epidemiological patterns revealed that the temporal dynamics of precipitation, which was abrupt and heavy, was presumably the determining factor. Analysis of the SST gradient showed that the Atlantic Ocean SST variability in 2005 differed from that of 2002 to 2004, a result of a prominent Atlantic meridional mode. The influence of this intense precipitation on cholera transmission over a densely populated and crowded region was detectable for both Dakar and Thiès, Senegal. Thus, high resolution rainfall forecasts at subseasonal time scales should provide a way forward for an early warning system in Africa for cholera and, thereby, trigger epidemic preparedness. Clearly, attention must be paid to both natural and human induced environmental factors to devise appropriate action to prevent cholera and other waterborne disease epidemics in the region.

In vitro vasorelaxation mechanisms of bioactive compounds extracted from Hibiscus sabdariffa on rat thoracic aorta

BackgroundIn this study, we suggested characterizing the vasodilator effects and the phytochemical characteristics of a plant with food usage also used in traditional treatment of arterial high blood pressure in Senegal.MethodsVascular effects of crude extract of dried and powdered calyces of Hibiscus sabdariffa were evaluated on isolated thoracic aorta of male Wistar rats on organ chambers. The crude extract was also enriched by liquid-liquid extraction. The various cyclohexane, dichloromethane, ethyl acetate, butanol extracts obtained as well as the residual marc were subjected to Sephadex LH-20 column chromatography. The different methanolic eluate fractions were then analyzed by Thin Layer (TLC) and High Performance Liquid Chromatography (HPLC) and their vascular effects also evaluated.ResultsThe H. Sabdariffa crude extract induced mainly endothelium-dependent relaxant effects. The endothelium-dependent relaxations result from NOS activation and those who not dependent to endothelium from activation of smooth muscle potassium channels. The phytochemical analysis revealed the presence of phenolic acids in the ethyl acetate extract and anthocyans in the butanolic extract. The biological efficiency of the various studied extracts, in term of vasorelaxant capacity, showed that: Butanol extract > Crude extract > Residual marc > Ethyl acetate extract. These results suggest that the strong activity of the butanolic extract is essentially due to the presence of anthocyans found in its fractions 43-67.ConclusionThese results demonstrate the vasodilator potential of hibiscus sabdariffa and contribute to his valuation as therapeutic alternative.

Prevalence of diabetes and associated risk factors in a Senegalese urban (Dakar) population

AIM The aim of this study was to estimate the prevalence of diabetes in the urban population living in Dakar, Senegal, and to investigate the factors associated with diabetes. METHODS Data from a 2009 survey of 600 individuals, aged 20 years or above and considered representative of the population of the city of Dakar, were evaluated. Socioeconomic characteristics, hypertension, capillary whole blood glucose, and weight and height measurements of these subjects were collected during face-to-face interviews. The statistical analyses used chi-square (chi2) tests and binary logistic regressions. RESULTS The percentage of participants with fasting blood glucose levels greater than or equal to 1.10 g/L and/or currently being treated for diabetes was 17.9% (n=107, 95% CI: 14.7-20.8). Observed rates of diabetes were significantly higher among women (chi2 = 6.3; P < 0.05), in subjects aged > 40 years (chi2=33.6; P < 0.001), in those with low educational levels (chi2=11.9; P < 0.05) and in those with hypertension (chi2 = 13.9; P < 0.001), and in those who were overweight (BMI ≥ 25 kg/m2 and < 30 kg/m2) or obese (BMI ≥ 30 kg/m2; chi2=40.3; P < 0.001). After adjusting for gender, age, educational level, BMI and blood pressure, the results showed that gender, age and BMI were associated with diabetes: women, older people and those with a higher BMI had significantly greater chances of being diabetic than the rest of the population, whatever their blood pressure and educational level. CONCLUSION Diabetes is becoming a pressing public-health problem in Senegal, and the major risk factors for the increasing diabetes prevalence in the city of Dakar are gender, age and body mass index.

Prevalence, awareness, treatment and control of hypertension among adults 50 years and older in Dakar, Senegal

Background Older adults are disproportionately affected by hypertension, which is an established risk factor for cardiovascular disease. Despite these facts, no study on the prevalence, awareness, treatment and control on arterial hypertension in Senegal has been conducted, specifically among elderly people. Methods Five hundred people aged 50 years and older, living in the city of Dakar were interviewed. This sample was constructed using the combined quota method in order to strive for representativeness of the target population. Results Prevalence of hypertension was 65.4% in our sample. Half of those suffering from high blood pressure were aware of their problem and among the latter, 70% said they were on treatment. However, of these, only 17% had controlled arterial blood pressure. The only factor associated with awareness, treatment and control of hypertension was the frequency of doctor visits. Conclusion Improving follow-up health checks of older adults are necessary to limit the consequences of hypertension in Dakar.

Hypertension prevalence, awareness, treatment and control in Dakar (Senegal).

The prediction of risk profile trends associated with non-communicable diseases in developing countries is among the greatest global health challenges. The aim of this study is to estimate prevalence, awareness, treatment and control of hypertension in Dakar (Senegal). This study was carried out between January and June 2009 on a population sample of 600 individuals living in the department of Dakar. This sample was constructed using the quota method in order to strive for representativeness. Sociodemographic characteristics, hypertension, hypertension awareness, treatment and control, and body mass index of individuals were collected during face-to-face interviews. Statistical analyses used were χ2-tests and binary logistic regressions. Prevalence of hypertension was 27.50%. Prevalence of awareness, treatment and control among hypertensives were 27.88%, 16.97% and 5.45%, respectively. Logistic regression showed that the prevalence, awareness and treatment of hypertension increased with increasing age. Overweight and obese subjects were more often hypertensive but did not differ from others in awareness and treatment. This could be linked to the social valorization of stoutness in West Africa, which explains that excess weight is not perceived as a risk factor for hypertension. In conclusion, given the very low rates of awareness, treatment and control in our sample, developing strategies for averting a hypertension epidemic must be a priority objective.

Migration and hypertension in Dakar, Senegal

This article examines social and environmental influences on the development of hypertension in a sample of 568 adults (290 men; 278 women) aged 20 years and older from Dakar, Senegal. We test the hypothesis that more recent immigrants to the city of Dakar will have lower blood pressure and lower rates of hypertension than those who have lived there longer. Cross-sectional sociodemographic, anthropometric and blood pressure data were collected during 2009. The overall prevalence of hypertension was 27.1% (95% CI: 25.2-29.0). Hypertension rates were not significantly associated with place of birth; however, length of residence in Dakar was a significant predictor, with those living in the city for less than 10 years having reduced risks of developing hypertension (OR = 0.25; P = 0.003). Other important correlates of blood pressure and hypertension risk in this sample were age and body mass index. These findings suggest that length of exposure to the urban environment-and associated changes in lifestyle-are linked to hypertension. Public health officials should thus pay particular attention to this phenomenon, and future anthropological research should include measures of both environmental and biological characteristics to study hypertension in Senegal.

Social representations of older adults [ magget ] in Dakar

ABSTRACT The objectives of this study in Dakar were twofold: to determine whether the representations of older adults are mainly positive, neutral or negative in the Senegalese capital; and to analyse the emic notions on which these age representations are based. As a first step in understanding how older adults are represented in this contemporary urban African context, a methodology was selected that is both quantitative and qualitative, including closed and open-ended questions to a representative cross-section of the Dakar population aged 20 years and over (N=600). The results indicate that representations of older adults, while heterogeneous, were mainly positive in Dakar: 63.7 per cent reported positive representations of older adults. Conversely, 17.5 per cent believed that older adults were perceived negatively. Lastly, 18.8 per cent reported that they did not perceive positive or negative social views of older adults. Representations of older adults were based on three principal notions: the value of advanced age, social usefulness of older adults and family ties. These results are discussed in the context of Dakar modernity, in comparison to Western modernity. Dakar society appears to depart from modernisation theory, as the experiential wisdom of older adults is still valued (mainly through the importance of oral tradition) and the extended family is upheld (given the permanent economic crisis the country is experiencing).

Dyslipidemia, obesity and other cardiovascular risk factors in the adult population in Senegal

Introduction According to the WHO, 50% of deaths worldwide (40.1% in developing countries) are due to chronic non-communicable diseases (NCDs). Of these chronic NCDs, cardiovascular diseases remain the leading cause of death and disability in developed countries. The Framingham study has shown the importance of hypercholesterolemia as a primary risk factor. In Senegal, the epidemiology of dyslipidemia and obesity are still poorly understood due to the lack of comprehensive studies on their impact on the general population. This motivated this study to look into the key epidemiologic and socio-demographic determinants of these risk factors. Methods It was a cross-sectional descriptive epidemiological survey which included 1037 individuals selected by cluster sampling. Data were collected using a questionnaire following the WHO STEPwise approach. Socio-demographic, health and biomedical variables were collected. P value <0.05 was considered to be statistically significant. Results The average age was 48 years with a female predominance (M: F of 0.6). The literacy rate was 65.2% and 44.7% of participants were from rural areas. The prevalence of hypercholesterolemia, hyperLDLemia, hypoHDLemia, hypertriglyceridemia and mixed hyperlipidemia were 56%, 22.5%, 12.4%, 7.11% and 1.9% respectively. One in four was obese (BMI> 30kg/m2) and 34.8% had abdominal obesity. The main factors significantly associated with dyslipidemia were obesity, urban dwelling, physical inactivity and a family history of dyslipidemia. Conclusion The prevalence of dyslipidemia, obesity and other risk factors in the population was high needing immediate care for those affected and implementation of prevention strategies.

Epidemiology of chronic kidney disease in northern region of Senegal: a community-based study in 2012.

Introduction Chronic kidney disease (CKD) is an emerging worldwide epidemic but few data are available in African populations. We aimed to assess prevalence of CKD in adult populations of Saint-Louis (northern Senegal). Methods In a population-based survey between January and May 2012, we included 1,037 adults aged =18 years living in Saint-Louis. Socio-demographical, clinical and biological data were collected during household visits. Serum creatinine was measured by Jaffé method. We estimated glomerular filtration rate (eGFR) using the 4-variables MDRD equation and CKD was defined by eGFR < 60 mL/min/1.73m2 and/or albuminuria > 1g/L. A multivariate logistic regression was performed to identify factors associated with CKD. Results Mean participants’ age was 47.9 ±16.9 years (18-87) and sex-ratio was 0.52. Majority of participants lived in urban areas (55.3% rural) and had school education (65.6%). Overall prevalences of hypertension, diabetes and obesity were 39.1%, 12.7% and 23.4% respectively. Prevalence of CKD was 4.9% (95% CI= 3.5 – 6.2) and 0.9% had GFR < 30 mL/min/1.73m2. Albuminuria >1g/l was found in 3.5% of people. CKD was significantly more frequent among hypertensive patients compared to normotensive participants. Only 23% of patients were aware of their disease before the survey. After multivariate logistic analysis, presence of CKD was significantly associated with hypertension (OR=1.12, p= 0.02) and age (OR=1.03, p= 0.02). Conclusion CKD is frequent in adult population living Northern Senegal. Main associated factors are hypertension and age. Prevention strategy is urgently needed to raise awareness and promote CKD detection and early treatment in both urban and rural areas.

Prevalence of Chronic Kidney Disease and Associated Factors in Senegalese Populations: A Community-Based Study in Saint-Louis

Background: Chronic kidney disease (CKD) is an emerging worldwide epidemic but littledata concerning African populations are available. Objectives: We aimed to assess prevalence of CKD in adult populations of Saint-Louis, northern Senegal. Patients and Methods: In a population-based survey between January and May 2012, we included 1037 adults ≥ 18 years of age who resided in Saint-Louis. Socio-demographic, clinical, and biologic data were collected during household visits. Serum creatinine was measured by Jaffé method. We estimated glomerular filtration rate (eGFR) using the four-variable Modification of Diet in Renal Disease (MDRD) equation and CKD was defined by eGFR< 60 mL/min/1.73 m2 and/or albuminuria > 1 g/L. A multivariate logistic regression was performed to identify factors associated with CKD. Results: The mean of participants’ age was 47.9 ± 16.9 years (range, 18-87) and sex ratio (male to female) was 0.52. Majority of participants lived in urban areas (55.3%) and had school education (65.6%). Hypertension, diabetes, and obesity were present respectively in 39.1%, 12.7%, and 23.4% of participants. Overall CKD prevalence was 4.9% (95% CI, 3.5-6.2) with eGFR< 30 mL/min/1.73 m2 in 0.9%. Albuminuria > 1 g/L was found in 3.5% of patients. CKD was significantly more frequent among hypertensive patients in comparison with normotensive ones. Risk factors associated with CKD were hypertension (12% of risk excess) and age (3% of risk excess). Conclusions: CKD is frequent in adult population living in Northern Senegal. Main associated factors are hypertension and age. Prevention strategies are urgently needed to raise public awareness and promote early CKD detection and treatment in both urban and rural areas.