The influence of smoking and lipids on restenosis after carotid endarterectomy

Factors associated with restenosis were investigated in 107 patients undergoing carotid endarterectomy for symptomatic disease. The patients, 71 men and 36 women with mean age 68 +/- 8 years, were followed up for 1 year by serial Duplex scanning. Carotid restenosis of > or = 50% developed in 18 patients (17%), 11 men and seven women. Restenosis was not influenced by age, sex, diabetes or hypertension. Continuing smokers, serum cotinine > 200 nmol/l, had a significantly higher incidence of > or = 50% restenosis after 1 year (39%), compared with only 16% of non-smokers, p = 0.023. Restenosis > or = 50% also was associated significantly with below median body mass index (p = 0.027). Women undergoing carotid endarterectomy had higher levels of cholesterol (median 7.4 mmol/l) and apolipoprotein B (median 0.81 g/l) than men (median cholesterol 6.4 mmol/l, median apolipoprotein B 0.69 g/l), p < 0.01. For men only, restenosis of > or = 50% was associated with low levels of serum cholesterol (median 5.7 mmol/l), p = 0.002. For women cholesterol levels were higher (median 8.1 mmol/l) in those with > or = 50% restenosis. Smoking adversely influences early restenosis (1 year) after carotid endarterectomy. Hyperlipidaemia is not a risk factor for restenosis in men, but may be associated with restenosis in women.

Within-individual variation in serum cholesterol levels: association with DNA polymorphisms at the apolipoprotein B and AI-CIII-AIV loci in patients with peripheral arterial disease

We have examined the association between variation at the apolipoprotein (apo) B gene and apo AI-CIII-AIV gene cluster and within-individual variation in serum cholesterol levels. Annual measurements were available over a period of 5-10 years in a group of 117 male patients with peripheral arterial disease. The overall within-individual coefficient of variation in cholesterol levels over time was 13.9%. For all patients, Restriction Fragment Length Polymorphism (RFLP) genotype at the apo B gene (XbaI and EcoRI) and apo AI-CIII-AIV gene cluster (XmnI, PstI and PvuII-CIII) had previously been determined. At the apo B locus, individuals heterozygous for either the XbaI or EcoRI RFLP showed significantly greater within-individual variability over time compared to individuals of other genotypes. At the apo AI-CIII-AIV gene cluster, individuals homozygous for the common allele of either the PstI or PvuIIA RFLPs showed the greatest within-individual variability over time but there was no difference in this estimate associated with XmnI genotype. Our observations suggest that variation at both the apo B and apo AI-CIII-AIV loci interacts with unidentified environmental factors to determine individual variability in serum cholesterol levels over time.

Plasma lipid and apolipoprotein profiles of women with two types of peripheral arterial disease

The purpose of this study was to establish whether women with peripheral arterial disease can be distinguished from controls on the basis of plasma lipid and apolipoprotein profiles. One group of patients with peripheral arterial disease (n = 20) was characterized by a localized aortic stenosis referred to as the 'small aorta syndrome' (SAS). The other group of patients with peripheral arterial disease (n = 23) had a diffuse segmental pattern of stenoses referred to as the 'stenosing peripheral arterial disease' (SPAD). After correcting for the effects of age and body mass index, the SAS group had elevated plasma total cholesterol (TC) levels when compared to normal controls (P less than or equal to 0.008), while the SPAD group had triacylglycerol (TG) levels different from controls (P = 0.02). Both groups of patients were characterized by reduced levels of apolipoprotein A-I (P less than or equal to 0.04) and increased levels of apolipoprotein C-III (P less than or equal to 0.002). Apolipoproteins B and E were also elevated in both groups of patients but not significantly. Mutivariate analyses indicated that the A-I/C-III ratio correctly discriminated 97.8% of the SAS and the A-I/C-III ratio plus A-I discriminated 89.8% of the SPAD patient from the controls. In addition, multivariate analyses showed that the variables age, TC/Apo B, Apo B/C-III and TG/C-III discriminated SPAD from SAS patients with a correct classification of 93.2%. Results of this study showed that the measurement of apolipoproteins A-I, B and C-III in conjunction with TC and TG is of potential use for differentiating patients with peripheral arterial disease from normal controls as well as for distinguishing patients with SAS from those with SPAD. It seems that particular patterns of peripheral arterial disease in women may be associated with slightly different alterations in the plasma lipoprotein system.

The effect of advice to stop smoking on arterial disease patients, assessed by serum thiocyanate levels

Serum thiocyanate has shown itself to be useful in distinguishing smokers from non-smokers. Our anti-smoking attitude resulted in 12 out of 32 smokers stopping smoking during the trial. Further, our evidence suggests that a patient who says he has given up smoking entirely can probably be believed, but a claim to have reduced smoking may be less reliable.

Multicompartmental analysis of amino acid. 1. Preliminary data on concentrations, fluxes, and flow constants of tryptophan in affective illness

The study of tryptophan metabolism using compartmental analysis suggested differences between males and females, and between control subjects and patients with affective illness, patients treated with tricyclic drugs, and those established on lithium therapy. The total mass of tryptophan in the body may be reduced in people prone to affective disorder, and in depressed patients(ill and well)turnover of tryptophan seemed to be reduced. The reduction of concentration of tryptophan in compartment S2 in affective illness could affect protein synthesis.