Prehypertension among adults in Great Tunis region (Tunisia): A population-based study.

PURPOSE: The present study aimed to determine the prevalence of prehypertension (preHTN) and its cardiometabolic profile in Tunisians, and to estimate the risk for coronary heart disease (CHD) according to blood pressure status. PATIENTS AND METHOD: This cross-sectional study was conducted in 2004-2005, and used a two-stage cluster sampling method to select a representative sample of the Great Tunis population. A total of 2712 individuals (1228 men and 1484 women), aged 35 to 69 years were included. Definition and classification of hypertension (HTN) was performed according to guidelines from the Joint National Committee on prevention, detection, evaluation and treatment of high blood pressure (JNC-7) report. RESULTS: The prevalence of preHTN and HTN was 56.8% and 25.0% in males, and 43.1% and 36.1% in females, respectively. Subjects with preHTN and those with HTN showed higher prevalence of diabetes, dyslipidemia, obesity and abdominal obesity than the normotensive (NT) group. The metabolic syndrome (MetS) was found in 8.0%, 17.8% and 53.8% of NT, preHT and HTN subjects, respectively. The risk of developing CHD within 10 years, as predicted by the Framingham-Anderson model, was above 15% for 3.9%, 31.1% and 65.0% among NT, preHTN and HTN subjects, respectively. In multivariate analysis, preHTN was associated with age (OR [95% CI], 1.02 [1.01-1.03]; P<0.01), male gender (2.51 [1.89-3.23]; P<0.001), obesity (2.36 [1.71-3.26]; P<0.01), abdominal obesity (1.53 [1.14-2.06]; P<0.01) and smoking (0.70 [0.53-0.92]; P<0.01). CONCLUSION: PreHTN is very common in Tunisians. It is associated with a higher prevalence of cardiometabolic risk factors and confers a higher risk for subsequent CHD. These findings support the recommendations of lifestyle modification for preHTN patients.

Plasma fatty acids profile and estimated elongase and desaturases activities in Tunisian patients with the metabolic syndrome.

This study aimed to determine plasma fatty acids pattern and to estimate desaturases activities in Tunisian subjects with metabolic syndrome (MetS). A total of 1975 adults were randomly selected from the Great Tunis region (Tunisia). MetS was defined according to the International Diabetes Federation criteria. Saturated and monounsaturated fatty acids levels and delta 9 desaturase activity were increased, but polyunsaturated fatty acids (PUFA) levels and delta 5 desaturase activity were decreased in patients with MetS. Using multivariate analysis, MetS was found inversely associated with PUFA; compared to first quartile, multi-adjusted odd ratios (95% confidence interval) of MetS were 0.80 (0.54-1.17), 0.47 (0.27-0.81) and 0.32 (0.15-0.68) for second, third and fourth quartiles of PUFA, respectively. Altered fatty acids pattern in MetS is likely related to both dietary and metabolic changes.

The G3057A LEPR polymorphism is associated with obesity in Tunisian women.

OBJECTIVES: The aim of this study was to evaluate the effect of the G3057A (rs62589000) LEPR polymorphism on obesity risk and plasma leptin, insulin, and lipid levels in a sample of the Tunisian population. DESIGN AND METHODS: Three hundred and ninety-three obese patients and 317 controls participated in this study. The G3057A genotype was determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS: In the entire study sample, no significant differences in genotype frequencies were observed between obese patients and controls. However, stratified analysis by gender revealed a quantitative increase in the variant allele (33.3% vs. 25.8%; χ(2)=4.90, p=0.026) in obese women (but not men) compared to controls. When a dominant model of inheritance was assumed, the GA+AA genotypes were more prevalent in these obese female patients than in controls (58.3% vs. 47.8%; χ(2)=4.08, p=0.044). Unconditional logistic regression showed that in women only, obesity risk was significantly higher for homozygotes for the variant allele (OR=2.73, 95% CI 1.03-7.21) and for carriers of GA+AA genotypes (OR=1.53, 95% CI 1.01-2.31) compared with homozygotes for the normal allele. The association between the G3057A LEPR variant and obesity remained statistically significant even after adjustment for age. No relationship was found between the G3057A LEPR polymorphism and leptin and insulin levels. Additionally, this LEPR gene variant had no effect on plasma lipid concentrations. CONCLUSION: There is evidence in this study that the G3057A LEPR polymorphism is associated with obesity in Tunisian women.

The metabolic syndrome: prevalence, main characteristics and association with socio-economic status in adults living in Great Tunis.

AIMS: This study aimed to determine the prevalence of the metabolic syndrome (MetS) and its association with socio-economic status in the population of Great Tunis. METHODS: The study included 2712 subjects (1228 men and 1484 women), aged 35-70 years and living in the Great Tunis region, all of whom were recruited between March 2004 and June 2005. The sample was weighted by using the inverse of the response rate according to governorate, district and gender. The MetS was defined according to the National Cholesterol Education Program-Adult Treatment Panel III. RESULTS: In the studied population, the overall prevalence of the MetS was 31.2%, and it was significantly more frequently seen in women than in men (37.3% vs 23.9%, respectively; P<0.001), as were abdominal obesity (69% vs 21.6%, respectively; P<0.001), high blood pressure (50.3% vs 43.1%, respectively; P<0.001) and low HDL cholesterol (40.6% vs 33.6%, respectively; P<0.001), the most common characteristics of the MetS. Also, the prevalence of the MetS increased with age in both genders, but more so in women. In those aged greater than 55 years, the prevalence of MetS was 56.7% in women and 30.7% in men. An inverse relationship was observed between level of education and prevalence of the MetS in women, with the highest prevalence being in illiterate women and the lowest in those who were university graduates. CONCLUSION: The prevalence of the MetS is markedly high within the population of Great Tunis and especially in women. As these findings predict future increases in cardiovascular disease in these populations, substantial efforts need to be made to fight against obesity and sedentary lifestyles to ameliorate the expected poor health outcomes.

[Prevalence of conventional cardiovascular risk factors in the Great Tunis population]. / Prévalence des facteurs de risque cardiovasculaires conventionnels dans la population du Grand Tunis.

BACKGROUND: This study was designed to determine the prevalence of main cardiovascular risk factors in the population of Great Tunis. SUBJECTS AND METHODS: This cross-sectional study included 2483 individuals aged 35 to 70 years dwelling in the Great Tunis region, recruited between March 2004 and June 2005. The sample was weighted using the inverse of response rate according to governorate, district and sex. RESULTS: Obesity and abdominal obesity were observed respectively in 34 and 48% of subjects. The prevalence of these two factors was particularly elevated in females (46 and 69% respectively). Hypertension was common (31%), especially in women (36%). Diabetes mellitus and dyslipemia were found in 15 and 21% of subjects, respectively, without difference according to sex. More than half of men and 8% of women were current smokers. CONCLUSION: The prevalence of conventional cardiovascular risk factors is dramatically high in the population of Great Tunis. These findings predict a future expansion of cardiovascular diseases in this population. Profound changes of lifestyle and dietary habits of Tunisians are needed to reduce the risk of cardiovascular morbidity and mortality.

Apolipoprotein B signal peptide polymorphism: distribution and influence on lipid parameters in Tunisian population.

Apolipoprotein B (apo B) is the major protein component of LDL, VLDL and chylomicrons. Numerous polymorphisms of the apolipoprotein B gene have been described. Particularly, the insertion/deletion polymorphism located in the coding part of the signal peptide of apo B, associated with modification of lipid concentrations and the risk of cardiovascular disease, has been reported in the general population. No such study in the Tunisian population has been performed. The aim of our study was to assess the effect of insertion/deletion polymorphism of the apolipoprotein B gene on lipid levels in a sample of the Tunisian population. A total of 458 unrelated subjects (321 men and 137 women) were included. The insertion/deletion polymorphism was determined by electrophoresis on polyacrylamide gels after PCR amplification. The relative frequencies of the Ins and Del alleles were 0.74 and 0.26, respectively. These frequencies were similar to those found in other Caucasian populations. There was no significant difference in serum TC, TG, and HDL-C levels due to the influence of the genotypes. However, significant variation among the three genotypes was seen for LDL-cholesterol (p<0.001) and apo B (p<0.001) levels. Individuals homozygous for the Del allele had higher levels than individuals homozygous for the Ins allele, while individuals heterozygous for both alleles exhibited intermediate levels. When the data were analyzed in men and women separately, a similar effect was seen in both groups. Our results show that distribution of apo B insertion/deletion polymorphism in Tunisians is similar to other Caucasian population and confirm the reported association with serum LDL-cholesterol and apo B concentrations.

Apolipoprotein E polymorphism in the Tunisian population: frequency and effect on lipid parameters.

OBJECTIVES: We determined the frequencies of apolipoprotein E (apo E) gene alleles and examined the association between apo E polymorphism and lipid parameters in a sample of the Tunisian population. DESIGN AND METHODS: Apo E polymorphism was investigated using PCR, and plasma lipid parameters were measured in 122 men and 111 women aged 35 to 87 years. RESULTS: The allele frequencies were epsilon2: 7.3%, epsilon3: 84.6%, and epsilon4: 8.1%. Apo E polymorphism was associated with significant differences (P<0.001) in total cholesterol, apo B and LDL cholesterol in both men and women. epsilon2 carriers had the lowest mean total cholesterol, apo B and LDL-C concentrations, and subjects with the epsilon4 allele had the highest levels. Triglycerides levels increased with the epsilon4 allele, but this did not reach statistical significance. These results remained unchanged after adjustment for age, body mass index, sex, hypertension, diabetes and smoking. However, in obese subjects (BMI>30 kg/m2), TG concentrations were significantly lower in individuals homozygous for the epsilon3 allele compared to those with the alleles epsilon2 or epsilon4. CONCLUSION: In this sample of the Tunisian population, the distribution of apo E gene alleles is similar to that observed in Southern European populations with low prevalence of the epsilon4 allele. Variations in the apo E gene play a role in determining plasma lipid levels. These data also suggest that effects of apo E alleles on lipids levels are partly dependent on environmental variables such as BMI. These findings highlight the importance of the gene/environment interaction on the deleterious effect of obesity on cardiovascular risk factors.

[Distribution of cardiovascular risk factors in a Tunisian cohort of 6901 coronary patients]. / Distribution des facteurs de risque cardiovasculaire chez une cohorte tunisienne de 6901 coronariens.

The Tunisian epidemiological data on cardiovascular disease in the hospital environment are scarce. The aim of this study was to evaluate the frequency of cardiovascular risk factors and their association in patients hospitalised for coronary disease in coronary care units at Rabta, Charles Nicolle, Habib Thameur and Military hospitals, Tunis, over the period 1994-1998. The clinical features of 6901 patients (75.7% men, 3760 myocardial infarction, 3141 unstable angina) on hospital admission were analysed. The prevalence of smoking, dyslipidemia, hypertension, diabetes and obesity was 86; 49.8; 33.9; 40.7 and 15.2% respectively in the men and 12.9; 52.4; 64.6; 53.4 and 29.8% respectively in women. With this risk factor profile Tunisia has to implement a national strategy of primary prevention and heart health promotion in addition to the efforts recently made in secondary prevention of some chronic disease such as hypertension, diabetes and smoking.