Background: The pathogenic role of hyperhomocysteinemia in cryptogenic stroke is not well established. We aimed to determine homocysteine levels in patients with cryptogenic stroke considering the possible variables that may act as confounders and analyze the influence of obesity on this association.Patients and methods: We conducted a case-control study in 123 patients with cryptogenic stroke aged 42 ± 12 years and in 153 control subjects aged 42 ± 13 years. Serum homocysteine was determined by fluorescence polarization immunoassay.Results: Patients showed statistically higher levels of homocysteine, creatinine and higher BMI than controls (p = 0.045, p = 0.014, p = 0.013), respectively. After multivariate adjustment the differences in homocysteine levels disappeared (p = 0.774). When subjects were classified according to the presence or absence of obesity, the differences in the prevalence of hyperhomocysteinemia (homocysteine >15 M) were highly significant, being higher in patients than in controls (p = 0.009). Likewise, mean values of homocysteine in obese were higher in cases than in controls (16.9 ± 9.5 M vs. 10.12 ± 2.5 M; p = 0.020), remaining significant after adjusting for the above mentioned confounders.Conclusion: Although in general, hyperhomocysteinemia does not seem to constitute an independent risk factor for cryptogenic stroke, it significantly increases the risk in obese subjects; therefore it is convenient to decrease its levels in this sub-group to minimize the risk.

Few data are available on genotype -phenotype interactions among familial hypercholesterolemia (FH) patients in South European populations and there are no data about the influence of R3500Q mutation on lipoprotein phenotype compared to low-density lipoprotein receptor (LDLR) mutations. The objective of the study is to analyze the influence of mutations in the LDLR and apolipoprotein B (apoB) genes on lipoprotein phenotype among subjects clinically diagnosed of FH living in East Spain. In all, 113 FH index patients and 100 affected relatives were studied. Genetic diagnosis was carried out following a protocol based on Southern blot and PCR-SSCP analysis. A total of 118 FH subjects could be classified into three groups according to the type of LDLR mutations (null mutations, missense mutations affecting the ligand binding 3-5 repeat, and missense mutations outside this domain). In addition, the lipoprotein phenotype of these FH groups was compared with 19 heterozygous subjects with familial ligand-defective apoB (FDB), due to R3500Q mutation. FH patients carrying missense mutations affecting the ligand binding repeat 3-5 showed total and LDL cholesterol levels significantly higher than FH patients with missense mutations in other LDLR domains or FDB patients. FH subjects carrying null mutations showed lower high-density lipoprotein cholesterol plasma values compared to FH carrying missense mutations. FDB subjects showed the lowest total and LDL cholesterol plasma values. In conclusion, the type of LDLR gene mutation and R3500Q mutation influences the lipoprotein phenotype of FH population from East Spain.

No abstract