Intima-media thickness of peripheral arteries in asymptomatic cigarette smokers

Evaluation of subclinical alterations in retinal layers and microvascular structures with OCT and OCTA in healthy young short-term smokers

PURPOSE

To detect the changes that can be determined with optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in young and short-term smokers.

METHOD

In this cross-sectional, observational, and comparative study, 45 "healthy" smokers and 45 healthy non-smoker control participants were included. Those with a smoking history between 1 year to 5 years and an average of 10-30 cigarettes per day were included in the study. OCT and OCTA measurements were made at least 60 min after smoking and at least 8 h after caffeine-containing beverages in order to end the effect of nicotine on systemic and retinal blood flow in the smoking group.

RESULTS

The mean smoking period was 2.2 ± 0.13 years. Mean macular thickness(MMT), retinal nerve fiber layer(RNFL), and choroidal thickness(Cht) were significantly lower in the smoker group, while ganglion cell-inner plexiform layer(GC-IPL) thickness was higher. Vessel density(VD) values were similar between groups, while perfusion density(PD) values were significantly higher in the smoker group. There were significant correlations between MMT and outer VD, outer PD, foveal avascular zone(FAZ) perimeter and circularity index. FAZ area and central VD and PD were inversely correlated. Also, FAZ circularity index and subfoveal, nasal, and temporal ChTs were positively correlated.

CONCLUSION

Despite the short-term smoking, ischemic effects were observed in retinochoroidal and vascular structures.

Evaluation of the effect of smokeless tobacco (Maras powder) on choroidal and retinal blood flow: an optical coherence tomography angiography study

ABSRTACT

PURPOSE: To investigate the acute and chronic effects of the use of smokeless tobacco (Maras powder) on macular and choroidal blood flow, via optical coherence tomography angiography (OCTA).

METHODS

The study included 30 eyes of 30 patients using smokeless tobacco (ST) as the study group and 30 eyes of 30 healthy individuals as the control group. All subjects underwent a full ophthalmological examination, and baseline OCTA measurements were taken. Flow area in superficial capillary plexus (SCP), in deep capillary plexus (DCP), in choriocapillaris (mm²⁾ and mean vascular density (VD) and foveal avascular zone in SCP and in DCP were assessed. Subfoveal choroidal thickness (SFCT) and central macular thickness were measured as well.

RESULTS

The SFCT measurements were determined to be significantly low in the study group (p < 0.001). In the comparison of the study group measurements at 5 m, 30 m and 1 h after using ST compared to the baseline measurements, SCP and DCP flow area, VD, CC flow area and SFCT were determined to have significantly decreased, statistically (p < 0.001).

CONCLUSION

OCTA could be important in showing that choroidal microvascular structures have been affected before occurence of the apparent clinical signs associated with acute and chronic ST use.

Evaluation of Foveal Avascular Zone and Capillary Plexus in Smokers Using Optical Coherence Tomography Angiography

Purpose:

To evaluate the macular microvasculature in smokers in comparison to healthy subjects using optical coherence tomography angiography (OCTA).

Methods:

Fifty chronic, regular smokers and 50 healthy non-smokers, as a control group, were recruited for the study. Foveal avascular zone (FAZ) area (mm²) and vessel density (VD) (%) in the superficial (SCP) and deep capillary plexus (DCP) were evaluated.

Results:

FAZ area was 0.424 ± 0.100 mm² in the smoker group and 0.333 ± 0.093 mm² in the non-smoking control group (P = 0.002). The deep foveal VD was 31.76 ± 6.33% in the smoker group and 53.09 ± 5.88% in the non-smoking control group (P = 0.006). Superficial foveal and parafoveal, deep parafoveal VD were not statistically different between the groups (P = 0.120), (P = 0.337), (P = 0.287), respectively.

Conclusion:

In our study, there was an enlargement of FAZ and reduction of foveal VD at DCP in the eyes of smokers compared with non-smoking adults.

Media sclerosis drives and localizes atherosclerosis in peripheral arteries

Media sclerosis (MS) and peripheral artery disease (PAD) may coincide, particularly in type 2 diabetics (T2D) and in patients with chronic kidney disease (CKD). In contrast to non-diabetics, in T2D PAD is more severe and more distal. Although MS is suspected to play a role, the underlying pathophysiological reasons for the differences still remain elusive today. We tested the hypothesis that MS is a promoter of atherosclerosis as it occurs in T2D with PAD by interfering with arterial remodeling using an in-silico simulation. We confirmed that MS aggravates PAD by promoting negative remodeling. We found that the effect is more pronounced in smaller distal arteries compared to larger proximal ones. Our results suggest that the degree of this divergence depends on the ratio between the thickness of the intima relative to the thickness of the media/adventitia of the individually affected arteries.

Intima-media thickness: indicator of cardiovascular risk and measure of the extent of atherosclerosis

The measurement of intima-media thickness (IMT) of large superficial arteries, especially the carotid, using high-resolution B-mode ultrasonography has emerged as one of the methods of choice for determining the anatomic extent of atherosclerosis and for assessing cardiovascular risk. IMT measurement obtained by ultrasonography correlates very well with pathohistologic measurements and the reproducibility of this technique is good. Population studies have shown a strong correlation between carotid IMT and several cardiovascular risk factors, and it has also been found to be associated with the extent of atherosclerosis and end-organ damage of high-risk patients. Therefore, increased carotid IMT is a measure of athero-sclerotic burden and a predictor of subsequent events. Because of its quantitative value, carotid IMT measurement is more and more frequently used in clinical trials to test the effects of different preventive measures, including drugs. More recently, there has been interest in the clinical use of this technique for detecting preclinical (asymptomatic) atherosclerosis and for identifying subjects at high risk. Measurement of carotid IMT could influence a clinician to intervene with medication and to use more aggressive treatment of risk factors in primary prevention, and in patients with atherosclerotic disease in whom there is evidence of progression and extension of atherosclerotic disease. For more extensive use of this method in clinical practice a consensus concerning the standardization of methods of measurement and precise definition of threshold between normal and pathologic IMT value is urgently needed.

[Thickness of carotid intima-media and cardiovascular risk factors]

Introduction

L’épaisseur intima-média de la carotide commune mesurée à l’échographie est un marqueur de risque cardio-vasculaire. L'objectif de ce travail est d’établir la corrélation entre l’épaisseur de l'intima-média carotidienne commune et les facteurs de risque cardio-vasculaire chez des sujets asymptomatiques.

Méthodes

Etude transversale descriptive et analytique portant sur 77 sujets de 40 ans et plus chez qui nous avons évalué les facteurs de risque cardio-vasculaire et analysé leur association avec l’épaisseur intima-média carotidienne commune.

Résultats

L’épaisseur intima-média augmentait avec l’âge. Les hommes avaient une épaisseur intima-média plus marquée que les femmes. L'hypertension artérielle, le diabète et la dyslipidémie sont corrélés à l’épaisseur de l'intima-média contrairement au tabagisme.

Conclusion

L’âge élevé et le sexe masculin sont les facteurs déterminants de la majoration de l’épaisseur intima-média carotidienne commune surtout si s'ajoutent l'hypertension artérielle, le diabète ou la dyslipidémie.

Effects of cigarette smoking on choroidal and retinal thickness and ocular pulse amplitude

BACKGROUND

In our study, we aimed to show the effects of smoking on choroidal thickness and ocular pulse amplitude. It is known that the anatomy and physiologic functions of the choroid is important in ocular diseases like glaucoma and age-related macular degeneration. Choroidal thickness is measured by the spectral domain optical coherence tomography (SD-OCT). The ocular pulse amplitude (OPA) is the difference between the systolic and diastolic intraocular pressure (IOP) and it is an index of choroidal perfusion.

DESIGN

This was a cross-sectional prospective observational study at the Turgut Ozal University Hospital setting.

PARTICIPANTS

The test subjects were divided into two groups: the smokers group which consisted in 24 participants (20 male, 4 female) and the control group with 22 participants (16 male, 6 female).

METHODS

The participants underwent full ophthalmological examination including best-corrected visual acuity (BCVA), spherical equivalent (SE) values of refractive errors, intraocular pressure (IOP), ocular pulse amplitude (OPA), central corneal thickness (CCT), axial length (AL) and choroidal thickness. The IOP and the OPA were measured with the dynamic contour tonometer. The CCT and the AL were measured with the Nidek AL-Scan (Nidek Co., Ltd., Gamagori, Japan). The choroidal thickness was measured by the Cirrus high-definition optical coherence tomography (Cirrus Version 6.0; Carl Zeiss Meditec, Dublin, CA).

RESULTS

Gender did not differ significantly between the groups (p = 0.12). The age, SE, IOP, OPA, CCT and AL did not differ significantly in smokers and control groups (p = 0.12, p = 0.37, p = 0.54, p = 0.80, p = 0.56 and p = 0.82, respectively). The nasal, temporal, central retinal (p = 021, p = 021, p = 0.11) and nasal, temporal, central choroidal thicknesses (p = 0.80, p = 0.39, p = 0.75) did not differ significantly between smokers and control groups.

CONCLUSIONS

We could not find a significant difference in OPA, retinal and choroidal thicknesses between smokers and non smokers. Further studies including histopathological changes in larger groups are needed to show the effect of smoking on choroidal thickness especially in patients with ocular diseases like age-related macular degeneration.

Effects of cigarette smoking, metabolic syndrome and dehydroepiandrosterone deficiency on intima-media thickness and endothelial function in hypertensive postmenopausal women

Background

Cigarette smoking is a major risk factor of atherosclerosis. The aim of this study was to assess the relationship between smoking and arterial hypertension as well as endothelial dysfunction in postmenopausal women without clinically manifested symptoms of atherosclerosis.

Material/Methods

The study groups consisted of 35 current smokers and 45 nonsmokers. The thickness of intima-media complex (IMT), a marker of atherosclerosis, was measured in carotid arteries. Plasma concentrations of fasting glucose, insulin, lipoproteins, inflammatory markers (tumor necrosis factor-alpha, intercellular adhesion molecule-1), matrix metalloproteinases (metalloproteinase-9, tissue inhibitor of metalloproteinase-1), insulin, and dehydroepiandrosterone sulfate (DHEA-S) were measured.

Results

Smokers compared with nonsmokers showed lower fasting glucose levels in blood (87.0±10.9 and 93.2±13.6 mg/dl, p<0.05), higher mean systolic (131.1±15.9 vs. 123.0±10.9 mm Hg, p<0.05) and diastolic (81.7±11.4 vs. 75.2±9.2 mm Hg, p<0.05) blood pressure during daytime, and higher average heart rate during the daytime (78.2±9.3/min vs. 71.5±9.5/min, p<0.01) and at night (67.2±10.6/min vs. 61.7±7.7/min, p<0.05), respectively. The IMT in the right carotid artery was significantly higher in smokers than in nonsmokers (0.96±0.16 mm vs. 0.82±0.21, p<0.05) and was positively correlated with smoking intensity (R=0.36) and habit duration (R=0.35). The comparison of inflammatory markers, metalloproteinases, and DHEA-S concentrations in plasma did not reveal significant differences between the 2 groups. A significant negative correlation between DHEA-S concentration in plasma and IMT in right carotid artery was found in smokers.

Conclusions

Smoking in hypertensive postmenopausal women is associated with lower fasting blood glucose and BMI values, but higher arterial pressure and heart rate, and increases in IMT in right carotid artery.

Effect of cigarette smoking on plasma homocysteine concentrations

BACKGROUND

Cigarette smoking has been recognized as a major risk factor for cardiovascular disease, while the role of homocysteine is still not clear. This study investigated the effects of smoking on plasma homocysteine concentration and determined the correlation between this parameter and biological markers of tobacco use, such as plasma thiocyanate and urine cotinine.

METHODS

Folate, vitamin B12 and homocysteine were measured in 300 subjects: 138 non-smokers and 162 smokers using immunoassay methods. Cotinine was measured using an enzymatic colorimetric method and thiocyanate by a selective electrode.

RESULTS

In smokers, we found a significant increase in homocysteine and a decrease in folate and vitamin B12 levels compared to non-smokers. Homocysteine was strongly correlated with the duration of use and the number of cigarettes consumed. Folate and vitamin B12 were significantly reduced in subjects smoking for more than 20 years compared to those who smoked less than 5 years. Among smokers, we noted a positive correlation between homocysteine and both plasma thiocyanates and cotininuria, and a negative-correlation between cotininuria and plasma folate.

CONCLUSIONS

Cigarette smoking increases homocysteine, which is strongly correlated with cotininuria and plasma thiocyanates. Moreover, smokers had tendency to develop hypofolatemia and hypovitamin B12, particularly when the duration of consumption exceeded 20 years.

Smoking and low serum testosterone associates with high concentration of oxidized LDL

BACKGROUND

The interplay between smoking, oxidized low-density lipoprotein cholesterol (ox-LDL) and gonadal hormones has been scarcely investigated.

AIM

To investigate associations in ox-LDL and gonadal hormones in smokers and non-smokers

METHODS

Participants (n=164) were obtained from a population cohort of Finnish men aged 40-70 years. The subjects answered a detailed questionnaire on their health behaviour, medication, diseases, and different symptoms, and the hormonal and lipid profiles were measured.

RESULTS

Smokers (n=33) had higher levels of ox-LDL (21%) and more free testosterone (12%) (P<0.01 for all) than non-smokers (n=131). The difference between smokers and non-smokers in ox-LDL persisted after controlling for possible confounding factors. When the smokers were divided into two subgroups (n=16 and n=17) according to total testosterone (< or =15 and >15 nmol/L), the ox-LDL in the low-testosterone subgroup was significantly higher (30%) than in the high-testosterone group (P=0.006). Similarly in the corresponding non-smoking subgroups (n=72 and n=59), ox-LDL was significantly higher (11%) in the low-testosterone subgroup than in the high-testosterone subgroup (P=0.012).

CONCLUSIONS

Smoking men have significantly more ox-LDL than non-smoking men. Furthermore, if smoking is combined with a low serum testosterone, ox-LDL is even higher. This may suggest a higher risk for atherosclerosis.

Serum adipocyte fatty acid-binding protein levels were independently associated with carotid atherosclerosis

OBJECTIVE

Adipocyte fatty acid-binding protein (A-FABP) has been shown to be an important player in atherosclerosis in animal models. However, the clinical relevance of these findings is still unknown. This study aims to examine the relationship between serum A-FABP level and carotid intima-media thickness (IMT), an indicator of atherosclerosis in humans.

METHODS AND RESULTS

The study cohort included 479 Chinese subjects who underwent carotid IMT measurement. Serum A-FABP levels were determined by enzyme-linked immunosorbent assays. Serum A-FABP levels positively correlated with carotid IMT in both men (r=0.211, P=0.001) and women (r=0.435, P<0.001). In women, but not in men, the presence of plaques was associated with significantly higher serum A-FABP levels (P<0.001 versus women without plaques). Stepwise multiple regression analysis showed that serum A-FABP level was independently associated with carotid IMT in women (P=0.034), together with age and hypertension (both P<0.001).

CONCLUSIONS

A-FABP is an independent determinant of carotid atherosclerosis in Chinese women, but not in men. This gender difference may be attributed to the lower serum A-FABP levels in men, and the effect of other risk factors, such as smoking, among our male participants. Our results have provided clinical evidence supporting the role of A-FABP in the development of atherosclerosis.

What is the role of non-invasive measurements of atherosclerosis in individual cardiovascular risk prediction?

Primary prevention of CVD (cardiovascular disease) is mainly based on the assessment of individual cardiovascular risk factors. However, often, only the most important (conventional) cardiovascular risk factors are determined, and every level of risk factor exposure is associated with a substantial variation in the amount of atherosclerosis. Measuring the effect of risk factor exposure over time directly in the vessel might (partially) overcome these shortcomings. Several non-invasive imaging techniques have the potential to accomplish this, each of these techniques focusing on a different stage of the atherosclerotic process. In this review, we aim to define the current role of various of these non-invasive measurements of atherosclerosis in individual cardiovascular risk prediction, taking into account the most recent insights about validity and reproducibility of these techniques and the results of recent prospective outcome trials. We conclude that, although the clinical application of FMD (flow-mediated dilation) and PWA (pulse wave analysis) in individual cardiovascular risk prediction seems far away, there may be a role for PWV (pulse wave velocity) and IMT (intima-media thickness) measurements in the near future.

Smoking status and common carotid artery intima-medial thickness among middle-aged men and women based on ultrasound measurement: a cohort study

Background

Cigarette smoking is an established causal factor for atherosclerosis. However, the smoking effect on different echogenic components of carotid arterial wall measured by ultrasound is not well elucidated.

Methods

Middle-aged men and women who had IMT measurement ≥ 0.7 mm at baseline and follow-up were included (N = 413, age 40–60 years at baseline in 1995). Intima-media thickness of common carotid artery (CCA-IMT) and its components (echogenic and echolucent layers) were measured at baseline and in the follow-up examination 3 years later. IMT and its components were compared across current, former and never smokers. Individual growth models were used to examine how smoking status was related to the baseline and progression of overall IMT and IMT components.

Results

For both men and women, current smoking was associated with thicker echogenic layer than never smokers; former smokers exhibited thinner echogenic layer than current smokers after adjustment for cigarette pack-years. Among women, current smoking was also associated with a thinned echolucent layer that resulted in a non-significant overall association of current smoking with IMT for women.

Conclusion

Cigarette smoking is associated with carotid artery morphological changes and the association is sex-dependent. The atherogenic effect of smoking appears to be partly reversible among former smokers. IMT measurement alone may not be adequate to detect carotid atherosclerosis associated with cigarette smoking among middle-age women.

Temporal trends in the incidence of intermittent claudication from 1950 to 1999

Declines in coronary disease and stroke mortality have occurred, but it remains unclear whether intermittent claudication (IC) incidence and mortality rates have changed. The authors sought to examine long-term trends for IC in the community. Cases of IC among Framingham Study participants aged >or=40 years were classified according to date of onset from the 1950s to the 1990s. IC was defined as the presence of exertional calf discomfort that was relieved with rest. Age- and sex-adjusted incidence rate ratios were estimated using log-linear Poisson regression, and 10-year survival was calculated using the Kaplan-Meier method. IC occurred in 668 participants (286 women). The age- and sex-adjusted incidence rate of IC fell from 282 per 100,000 person-years during the period 1950-1969 to 225 per 100,000 person-years in the 1990s. The decline in IC incidence across time periods was significant (p for trend=0.01), with an initial increase in the 1970s being followed by declines of 16% in the 1980s and 18% in the 1990s. Approximately 40% of persons with IC died within 10 years of diagnosis, with no significant change occurring during the study period. IC incidence has declined since 1950, but mortality has remained high and unchanged. Factors contributing to the declining incidence of IC need clarification.

[Cigarette smoking in military pilots and intima-media thickness of the carotid arteries]

BACKGROUND

It is well known that smoking is associated with an increase in arterial wall thickness. However, most studies of this problem have been undertaken in age and sex heterogenous groups, as well as in patients with already present other conventional risk factors. The aim of this study was to assess the effect of cigarette smoking on arterial wall thickness of the common carotid artery in asymptomatic pilots.

METHODS

The imaging of intima-media thickness of the posterior wall of the distal 1 cm of both common carotid arteries was performed using a B mode ultrasound device, in 39 pilots (37.05 +/- 6.66 years), for whom smoking was the single cardiovascular risk factor. Comparisons were made with 49 non-smokers (35.12 +/- 7.39 years).

RESULTS

The posterior walls of both common carotid arteries were thicker in smokers (left, p < 0.05; right, p > 0,05). Intima-media thickness was significantly lower on the right side than on the left side in both smokers and non-smokers (p < 0.01).

CONCLUSION

Cigarette smoking as the single cardiovascular risk factor was associated with the wall thickness of the carotid arteries in our study. This finding indicated that early atherosclerosis was already present in pilots-smokers entering middle age.

Impact of Smoking on Endovascular Abdominal Aortic Aneurysm Surgery Outcome

OBJECTIVE

Smoking plays a major role in deficiencies of the vascular system, and seems to have consequences for the treatment of cardiovascular diseases. We hypothesized that smokers have a higher mortality and more complications after endovascular abdominal aortic aneurysm surgery than non-smokers.

METHODS

We assessed mortality and complications of 3270 patients who underwent endovascular abdominal aortic aneurysm surgery in Europe between January 1994 and July 2001. Survival and (post) operative complications were assessed by smoking status.

RESULTS

Mortality did not significantly differ between smokers and non-smokers. Smokers had a higher number of intra-operative additional procedures, but a lower number of late endoleaks in comparison to non-smokers. In addition, smokers had a reduced risk of late type II endoleaks in comparison with non-smokers.

CONCLUSION

There seems to be no significant difference in endovascular abdominal aortic aneurysm surgery outcome between smokers and non-smokers, although there were significant differences in intra-operative additional procedures and late endoleaks.

Family history is a major determinant of subclinical peripheral arterial disease in young adults

BACKGROUND

Cardiovascular disease is prevalent in first-degree relatives of young adults with premature-onset peripheral arterial occlusive disease (premature PAD), but it is not known whether the genetic influence is independent of other risk factors, the most prevalent of which is smoking. This study was performed to determine the relative contributions of family history and smoking to the development of occult PAD in siblings of patients with premature PAD.

METHODS

The prevalence of occult PAD was determined with carotid, abdominal, and lower extremity duplex ultrasound scanning in 50 asymptomatic siblings (25 men, 25 women) of patients with premature PAD (onset <or=49 years). Thirty of the siblings (60%) were active smokers, and 20 had never smoked. Age-matched and sex-matched reference groups included 50 asymptomatic heavy smokers (>20 cigarettes/day) and 50 nonsmokers.

RESULTS

Duplex ultrasound scans demonstrated raised arterial lesions in 20 asymptomatic siblings (40%), 20 heavy smokers (40%), and 2 nonsmoking control subjects (4%), resulting in 42 affected and 108 unaffected subjects. As expected, smokers were far more likely to have arterial lesions than were nonsmokers (odds ratio [OR], 11.19; 95% confidence interval [CI], 4.1-30.7; P <.0001). Individuals with a family history of premature PAD were almost three times more likely to have arterial lesions than those with no family history of cardiovascular disease (OR, 2.76; 95% CI, 1.3-5.8; P =.006). Stratified and multivariable logistic regression indicated no interaction between smoking and family history, indicating simple additive effects on PAD.

CONCLUSIONS

Family history is a major determinant of occult PAD in young adults, and is at least as important as standard atherosclerotic risk factors. A high proportion of heavy smokers have clearly detectable lesions even though asymptomatic. Smoking and family history act additively to increase the risk for premature PAD.

Prospective evaluation of hypertensive patients with carotid kinking and coiling: an ultrasonographic 7-year study

The aim of this study was to determine the incidence of vascular events during a 7-year follow-up evaluation in a group of 34 hypertensive patients with kinking of the internal carotid artery and 36 well-matched hypertensive control subjects. The carotid intima-media thickness (IMT) was measured at three points of the carotid bifurcation and at three points of carotid kinking on the ultrasonographic posterior wall. The mean IMT measured in the segment of the angular bending was lower than the mean values detected at the bifurcation in normal subjects and in hypertensives without carotid elongation (p < 0.01). At the carotid bifurcation of the same side of the kinking, there was an arterial IMT that was significantly lower as compared to the contralateral axis and to the measurements obtained in other hypertensive subjects. During a 7-year follow-up study, 10 vascular events occurred in the hypertensives with carotid kinking and 14 in the controls, without significant differences between the 2 groups. In hypertensives with carotid kinking, the mean IMT measured on the angular bending and at the ipsilateral carotid bifurcation was significantly lower than the values obtained at the contralateral bifurcation and in the other hypertensive subjects. In the 7-year follow-up study, moreover, the presence of carotid kinking does not impact the incidence of vascular events in the hypertensive population. Thus, the presence of carotid kinking in hypertensive subjects may not be considered a further risk factor for ischemic events.

Influence of apolipoprotein E, smoking, and alcohol intake on carotid atherosclerosis: National Heart, Lung, and Blood Institute Family Heart Study

BACKGROUND AND PURPOSE

Apolipoprotein E (apoE) isoforms and lifestyle factors play an important role in the development of coronary heart disease. The association of apoE and carotid atherosclerosis remains controversial.

METHODS

We investigated the relation of apoE, cigarette smoking, alcohol drinking, and their interaction with carotid atherosclerosis on 544 individuals free of coronary heart disease in the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study. Atherosclerotic lesions of the carotid arteries were detected through high-resolution ultrasound.

RESULTS

Subjects in the apoE4 group had lower blood pressure, lower high-density lipoprotein cholesterol, and higher low-density lipoprotein cholesterol. In a multivariate logistic regression model, apoE isoforms and alcohol consumption were not significantly associated with the prevalence odds of carotid atherosclerosis (P=0.94 and 0.98, respectively, for trend). In contrast, compared with those who never smoked, the prevalence odds ratios for carotid atherosclerosis were 1.7 [95% confidence interval (CI),1.1 to 2.7], 2.8 (95% CI, 1.2 to 6.2), and 1.9 (95% CI, 0.7 to 5.5) for former smokers, current smokers of 1 to 20 cigarettes per day, and current smokers of >20 cigarettes day, respectively (P=0.0018 for trend). We did not find evidence of an interaction between apoE and alcohol consumption. Our data suggested a synergistic effect between the apoE allele epsilon(4) and smoking on carotid atherosclerosis: odds ratios were 1.7 (95% CI, 0.8 to 3.6) for smoking alone, 1.0 (95% CI, 0.6 to 1.8) for epsilon4 alone, and 3.7 (95% CI, 1.1 to 3.6) for the joint presence of the apoE allele epsilon4 and smoking.

CONCLUSIONS

Smoking but not alcohol consumption or ApoE is associated with an increased odds of carotid atherosclerosis. Our data suggest a synergistic effect between the apoE allele epsilon4 and smoking on carotid atherosclerosis.

The early effect of lipid-lowering treatment on carotid and femoral intima media thickness (IMT)

OBJECTIVES

an increased intima media thickness (IMT) is an early indicator of the atherosclerotic process. We investigated the early effect of atorvastatin on the common carotid artery (CCA) and common femoral artery (CFA) IMT.

METHODS

the IMT was measured in the CCA and the CFA of hyperlipidaemic patients referred with peripheral vascular disease. The measurements were performed using an automated radio frequency IMT technique pre-treatment and at 4 and 8 weeks post-treatment with 20 mg/day atorvastatin.

RESULTS

patients (14 men; 11 women), median age 69 years (range: 48-81) had a CCA-IMT mean (SD) of 0.79 (0.21) mm pre-treatment, 0.75 (0.22) mm after 4 weeks, and 0.64 (0.15) mm after 8 weeks. The ANOVA test was significant (p=0.024) for the CCA-IMT trend. The corresponding CFA-IMT readings were 0.83 (0.13) mm, 0.80 (0.09) mm and 0.69 (0.14) mm (p=0.0003). After 8 weeks of treatment there was a significant reduction in total cholesterol 6.0 (0.3) to 4.3 (0.8) mmol/l, p=0.0004 and low-density lipoprotein cholesterol 3.7 (0.2) to 2.2 (0.5), p=0.0001. There was a significant decrease in median serum creatinine levels after 8 weeks treatment: 87 micromol/l (range 67-114) to 84 micromol/l (range: 64-112), p=0.007.

CONCLUSIONS

cholesterol-lowering with atorvastatin 20 mg/day leads to a decrease in CCA-IMT and CFA-IMT. This difference achieved significance after 8 weeks of treatment, but a trend was visible at 4 weeks. These rapid changes in IMT may be attributable to an anti-inflammatory effect. IMT measurement may be a useful tool to rapidly assess the effect of drug treatment on the atherosclerotic process.

No evidence of accelerated atherosclerosis in a 66-yr-old chylomicronemia patient homozygous for the nonsense mutation (Tyr61-->stop) in the lipoprotein lipase gene

Whether chylomicronemia is atherogenic or not has yet to be determined in humans. We investigated a 66-yr-old female with severe chylomicronemia resulting from a lipoprotein lipase (LPL) deficiency. The patient's plasma triglyceride level was approximately 2000 mg/dl. Both LPL activity and the mass of postheparin plasma in this patient were virtually absent. A nonsense mutation in exon 3 (Tyr61-->Stop) was identified in the patient's LPL gene, and a restriction fragment length polymorphism analysis established that the patient was homozygous for this mutation. The patient was neither a diabetic nor a smoker. Clinically, the patient had never experienced pancreatitis or angia pectoris. An examination of her carotid, femoral and coronary arteries by ultrasonogram and electrocardiogram after exercise-tolerance testing showed no accelerated atherosclerosis. This case suggests that atherosclerosis may not occur despite massive hyperlipidemia, when LPL bridging was not present due to the absence of LPL secretion and circulating mass.

Smoking diminishes the beneficial effect of statins: observations from the landmark trials

The landmark statin trials showed a significant reduction in morbidity and mortality associated with ischemic heart disease. However, it may not be widely appreciated that smoking had a marked adverse effect on outcome in these trials. In both the primary and secondary prevention setting, the effect of smoking was broadly similar. Smoking markedly increased the risk of events in the placebo and treatment groups. For example, in the primary prevention trials, this risk was 74-86% higher when smokers were compared with nonsmokers in the placebo groups. The corresponding figures for the secondary prevention trials were 23-61%. The risk of events in untreated nonsmokers was of a similar order to that seen in smokers taking statins. Although statin treatment was associated with a significant reduction in events in smokers, the best outcome was observed in nonsmokers treated with statins (primary prevention: lovastatin or pravastatin; secondary prevention: pravastatin or simvastatin). The highest risk of events in any group was in the smokers on placebo. This information may increase clinician and patient awareness as to the marked harmful effect of smoking relative to effective, evidence-based treatment (ie, the use of statins).