Metabolic syndrome in Tunisian psoriatic patients: prevalence and determinants.

BACKGROUND: A significant association between psoriasis and the metabolic syndrome (MetS) has been frequently reported. OBJECTIVE: The aim of this study was to specify the main factors that determine the MetS in psoriatic Tunisian patients. METHODS: A case-control study has included 164 psoriatic patients and 216 controls. RESULTS: The prevalence of MetS was higher in cases than in controls but without statistical differences [35.5% vs. 30.8%, odds ratio (OR): 1.39 CI: 0.88-2.18; P=0.095]. According to gender, the prevalence of MetS was significantly increased only in psoriatic women (47.4% vs. 30%, OR: 1.89, CI: 1.11-3.21; P=0.01). A multiple logistic regression, considering the effect of age, and gender, showed that the prevalence of MetS was significantly higher in cases than in controls (OR: 1.73, CI: 1.06-2.82; P=0.03). MetS components analysed seperately showed a significantly higher prevalence of decreased high-density lipoprotein cholesterol (HDLc) (60.9% vs. 35.9%, OR: 2.77, CI: 1.8-4.27, P<0.001) and for increased hypertension (50% vs. 40%, OR: 1.48, CI: 0.97-2.257, P=0.04) in psoriatic patients. According to gender, HDLc was significantly decreased in both genders (male: OR: 2.075, CI: 1.24-3.47, P=0.004; female: OR: 3.58, CI: 2.07-6.19, P<0.0001), while hypertension was increased only in psoriatic men (OR: 2.09, CI: 1.24-3.51, P=0.004) and abdominal obesity only in psoriatic women (OR: 2.31, CI: 1.30-4.11, P=0.002). CONCLUSION: Decreased HDLc is the main biological abnormality that characterized MetS in Tunisian psoriatic patients. Moreover, contrary to men, psoriatic women have shown a significantly higher prevalence of MetS, which is, in addition to decreased HDLc, mainly attributed to abdominal obesity.

[XbaI polymorphism of apolipoprotein B gene in a Tunisian population: alleles frequencies and relationship with plasma lipid parameters]. / Polymorphisme XbaI du gène de l'apolipoprotéine B dans une population tunisienne: fréquences alléliques et relation avec les paramètres lipidiques plasmatiques.

Apolipoprotein B (Apo B) is a component of chylomicrons, low-density lipoproteins (LDL), very low density lipoproteins (VLDL), and intermediate-density lipoproteins (IDL) and is the ligand for the LDL receptor. Thereby, Apo B plays a central role in lipoprotein metabolism and in maintaining the normal homeostasis of serum cholesterol levels. Several Apo B restriction fragment length polymorphisms (XbaI, EcoRI, MspI) have been reported to be associated with variation in lipid levels, obesity and/or coronary artery disease. To date, no data are available on relationship between XbaI Apo B polymorphism and lipid levels in Tunisian population. Here, we report frequencies of the XbaI polymorphism of the Apo B gene and we assess the effect of this polymorphism on lipid and lipoprotein concentrations in Tunisian population. Blood samples from 296 Tunisian individuals (112 women and 184 men, aged 51.4+/-9.6 years), were analysed for total cholesterol, triglycerides, HDL-cholesterol and apolipoproteins A1 and B. In parallel, genotyping by means of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) was performed. The XbaI polymorphism was associated with differences in plasma cholesterol (p=0.04), triglyceride (p=0.02) and apolipoprotein A1 (p=0.004), individuals with the genotype X1X1 have the lowest mean levels and those with the genotype X2X2 have the highest, with the individuals heterozygous for the polymorphism having intermediate levels. According to sex, the XbaI polymorphism effect was only observed for triglyceride in men. Thus, the results demonstrate an influence of XbaI polymorphism of Apo B gene on serum total-cholesterol, triglycerides and apolipoprotein A1 concentrations among Tunisian population.

[VNTR3' polymorphism of apoliproprotein B gene in obese people]. / Polymorphisme VNTR3' du géne de l'apolipoprotéine B chez les sujets obèses.

Apolipoprotein B (apo B) is the major component of LDL, VLDL and chylomicrons. Variations of lipid concentrations in obese people result from obesity, nutritional and genetic factors. Many genetic polymorphisms of the apo B have been described, associated with variation of lipid concentrations. The aim of the present study was to assess the effect of VNTR3' polymorphism of the apoB gene on lipid and lipoprotein concentrations in overweight subjects. 234 unrelated outpatients (160 women and 74 men, aged 39.3 y 10.5; BMI: 32.8 kg/m2 4.7) were recruited. Using the polymerase chain reaction followed by electrophoresis in polyacrylamide gels, 15 different alleles have been identified. Among them four have been observed less than 5 times in our study. Alleles with 21, 25, 35 and 42 repeats have been observed once. The most frequent is VNTR36 allele (38%), followed by alleles 34, 30, 48, and 46 repeats whose frequencies are 20, 9, 8, and 7% respectively. The possible association between alleles of the VNTR3' of the apoB and anthroprometric and lipid variables was examined. Subjects with 50 repeat allele had significantly higher BMI, and subjects with 32 repeat allele had significantly higher HDL-C and ApoAI levels. Our study confirms in the obese subjects, results published in the general litterature, and shows that the apoB has an important role in the metabolism of plasma lipids and most particulary its gene variants.