Immunoglobulin A antibodies against Chlamydia pneumoniae are associated with expansion of abdominal aortic aneurysm.

BACKGROUND: The aim of this study was to examine the possible association between the progression of small abdominal aortic aneurysm (AAA) and chronic infection with Chlamydia pneumoniae. METHODS: Patients from a hospital-based mass screening programme for AAA with annual follow-up (mean 2.7 years) were included. After initial interview, 139 men aged 65-73 years with a small AAA underwent examination and blood sampling. Immunoglobulin (Ig) G and IgA titres against C. pneumoniae were measured by a microimmunofluorescence test. RESULTS: Some 83 (95 per cent confidence interval 74-93) per cent of the men had an IgA titre of 20 or more, or an IgG titre of 32 or more. Men with an IgA titre of 20 or more had a 48 per cent higher AAA expansion rate than those with a titre of less than 20 (3.1 versus 2.1 mm/year; P < 0.05). Multiple linear and logistic regression analyses showed that an IgA titre of 20 or more was a significant independent predictor of increased AAA expansion, adjusted for known risk factors of expansion. Initial AAA size and serum total cholesterol level were also predictors of expansion. CONCLUSION: A high proportion of men with a small AAA had signs of chronic infection with C. pneumoniae. Aneurysm progression correlated with evidence of chronic C. pneumoniae infection.     

Chlamydia pneumoniae,overall and cardiovascular mortality in end-stage renal disease (ESRD)

BACKGROUND: Cross-sectional and retrospective studies suggest that Chlamydia pneumoniae infection may contribute importantly to the high cardiovascular risk of patients with end-stage renal disease (ESRD). METHODS: We investigated the relationship between C. pneumoniae serology and survival and incident fatal cardiovascular events in a cohort of 227 ESRD patients (follow-up of 39 +/- 20 months). RESULTS: On univariate Cox regression analysis patients with anti-C. pneumoniae immunogloblulin A (IgA) titer > or = 1:16 had a significantly higher risk of all-cause and cardiovascular mortality when compared to patients without IgA antibodies. However, after data adjustment for age and smoking, the hazard ratio (HR) decreased substantially and became largely nonsignificant. Adjustments for traditional and nontraditional risk factors further decreased the independent association of IgA anti-C. pneumoniae and these outcomes (all-cause mortality HR, 1.08; 95% CI, 0.68 to 1.72; P = 0.74; cardiovascular mortality HR, 1.07; 95% CI, 0.60 to 1.89; P = 0.83). A similar loss of prognostic power was observed for IgG anti-C. pneumoniae so that in fully adjusted models the HRs were very close to those observed for IgA anti-C. pneumoniae (all-cause mortality HR, 1.13; 95% CI, 0.68 to 1.86, P = 0.64; cardiovascular mortality HR, 1.10; 95% CI, 0.60 to 2.00; P = 0.77). CONCLUSION: C. pneumoniae seropositivity is associated to shorter survival and incident fatal cardiovascular events in patients with ESRD but these associations are in large part attributable to the link between C. pneumoniae and well-established, traditional risk factors. It is highly unlikely that C. pneumoniae infection is a major risk factor in patients with ESRD.     

Use of doxycycline to decrease the growth rate of abdominal aortic aneurysms: a randomized, double-blind, placebo-controlled pilot study.

OBJECTIVE: Eradication of Chlamydia pneumoniae infection and inhibition of elastolytic matrix metalloproteinases with doxycycline have been suggested to reduce the growth rates of small abdominal aortic aneurysms (AAA). We designed a study to investigate the efficacy of doxycycline in reducing the expansion of small AAAs. SUBJECTS AND METHODS: This was a prospective, double-blind, randomized, placebo-controlled study that was set in a university referral hospital. The study group consisted of 32 of 34 initially eligible patients who had an AAA diameter perpendicular to the aortic axis of 30 mm or more in size or a ratio of infrarenal to suprarenal aortic diameter of 1.2 or more and a diameter less than 55 mm. Patients were randomly assigned to receive either doxycycline (150 mg daily) or placebo during a 3-month period and underwent ultrasound surveillance during an 18-month period. Outcome measures included aneurysm expansion rates, the number of patients who had AAA rupture or repair, C pneumoniae antibody titers, and serum concentrations of C-reactive protein. RESULTS: The aneurysm expansion rate in the doxycycline group was significantly lower than that in the placebo group during the 6- to 12-month (P = .01) and the 12- to 18-month periods (P =.01). Five patients (41%) in the placebo group and 1 patient (7%) in the doxycycline group had an overall expansion of the aneurysm of 5 mm or more during the 18-month follow-up. Among the placebo group patients, a higher expansion rate was observed in those with enhanced C pneumoniae immunoglobulin G antibody titers (> 128) than in those with lower titers (P = .03). Doxycycline treatment had no clear effect on antibody titers. However, at 6-month follow-up, C-reactive protein levels in the doxycycline group were significantly lower than the baseline levels (P = .01). CONCLUSIONS: The results of this small pilot study suggest that doxycycline may favorably alter the outcome of patients with small AAA. However, because of the small size of this randomized study and of the potentially confounding effect of pretreatment risk factors, doxycycline-based treatment cannot be justified only on the ground of the current results. Because of the high prevalence of this disorder and its clinical, social, and economic relevance, a multicenter study should be performed to further investigate whether there is any place for medical treatment of small AAAs.     

Cystatin C deficiency is associated with the progression of small abdominal aortic aneurysms.

BACKGROUND: The cysteine protease inhibitor cystatin C may play a role in the development and progression of abdominal aortic aneurysms (AAAs). METHODS: From a mass screening trial of men aged 65-73 years, 151 small AAAs were followed for a mean of 2.9 years. Of these patients, 142 had serum samples taken to determine the levels of cystatin C, creatinine and C-reactive protein (CRP). RESULTS: Serum cystatin C concentration correlated negatively with AAA size (r = - 0.22 (95 per cent confidence interval (c.i.) - 0.59 to - 0.02)) and annual expansion rate (r = - 0.24 (95 per cent c.i. - 0.75 to - 0.05)), persisting after adjustment for renal function, smoking, diastolic blood pressure, CRP, age and AAA size. Creatinine clearance and CRP did not correlate with size or expansion rate. Thirty-one AAAs had expanded to over 50 mm, when operation was recommended. The serum level of cystatin C was a significant predictor of this occurrence, with a sensitivity and specificity of 61 and 57 per cent respectively. However, initial AAA size had the optimal sensitivity and specificity (both 81 per cent) in this regard. CONCLUSION: Deficiency of cystatin C was associated with increased aneurysm size and expansion rate, possibly due to lack of inhibition of cysteine proteases.     

Randomized double-blind controlled trial of roxithromycin for prevention of abdominal aortic aneurysm expansion

BACKGROUND: Macrolide treatment has been reported to lower the risk of recurrent ischaemic heart disease. The influence of macrolides on the expansion rate of abdominal aortic aneurysms (AAAs) remains unknown. The aim was to investigate the effect of roxithromycin on the expansion rate of small AAAs. METHODS: A total of 92 subjects with a small AAA were recruited from two populations. One population consisted of 6339 men aged 65-73 years who were offered a hospital-based mass screening programme for AAA. From this population 66 subjects were recruited. The remaining 26 men were recruited from among 49 subjects diagnosed at interval screening for an initial aortic diameter between 25 and 29 mm. Subjects were randomized to receive either oral roxithromycin 300 mg once daily for 28 days or matching placebo, and followed for a mean of 1.5 years. RESULTS: During the first year the mean annual expansion rate of AAAs was reduced by 44 [corrected] per cent in the intervention group (1.56 mm per year), compared with 2.80 mm per year following placebo (P = 0.02). During the second year the difference was only 5 per cent [corrected]. Multiple linear regression analysis showed that roxithromycin treatment and initial AAA size were significantly related to AAA expansion when adjusted for smoking, diastolic blood pressure and immunoglobulin A level of 20 or more [corrected]. Logistic regression analysis confirmed a significant difference in expansion rates above 2 mm annually between the intervention and placebo groups: odds ratio = 0.09 (95 per cent confidence interval 0.01-0.83) [corrected]. CONCLUSION: In comparison to placebo, roxithromycin 300 mg daily for 4 weeks reduced the expansion rate of AAAs.     

Existence of abdominal aortic aneurysms in patients with thoracic aortic dissections

OBJECTIVE: The objective of this study was to determine the coexistence or later development of pararenal and infrarenal abdominal aortic aneurysms (AAAs) in patients with thoracic aortic dissections. METHODS: One hundred forty-five patients (95 men, 50 women) encountered from 1992 to 2001 with thoracic aortic dissections-excluding those associated with trauma, those with Marfan's syndrome, and those with thoracoabdominal aortic aneurysms-were studied. The most common risk factors included hypertension (59%) and a history of tobacco use (52%). Type III dissections affected 86 patients (59%), and type I dissections affected the remaining 59 patients (41%). Aortic computed tomography (CT) scans were obtained annually. Data were assessed by univariate and multivariate analyses. RESULTS: Five patients (3%) had a history of AAA repair prior to their thoracic aortic dissection diagnosis-3 were type III dissections and 2 were type I dissections. Twelve patient's (8%) AAAs were diagnosed with the initial CT study of their thoracic aortic dissection. Type III dissections accounted for all but one of these (11 of 12, 92%). Ten additional AAAs (7%) developed in the 128 patients with no initial evidence of an AAA being recognized from 1 to 48 months (average 16 months) after the thoracic aortic dissection was diagnosed. Type III dissections affected 8 of these 10 patients. Among the total 27 AAAs noted in this series, 74% (20 AAAs) were not continuous with the thoracic aortic dissection. In the univariate analysis, age (P =.0002), male gender (P =.044), history of smoking (P =.01), chronic obstructive pulmonary disease (P <.001), duration of dissection (P =.05), and presence of type III dissection (P =.009) were associated with the presence of an AAA. In the multivariate analysis, both chronic obstructive pulmonary disease (odds ratio 5.4, 95% CI, 1.3 to 22.3; P =.02) and age (OR 1.06, 95% CI, 1.02 to 1.11; P =.004) were significant predictors of the development of AAAs. CONCLUSION: This study documented that patients with thoracic aortic dissections are at risk to harbor or develop a later AAA. This finding supports the tenet that abdominal CTs or ultrasound scanning should be mandatory in the follow-up of patients with known thoracic aortic dissections.     

Lack of association between Chlamydophila pneumoniae seropositivity and abdominal aortic aneurysm

Chronic Chlamydophila pneumoniae infection has been suggested as a possible contributing factor for the development and expansion of abdominal aortic aneurysm (AAA). The relevance of C pneumoniae involved in the processes underlying aneurysmal rupture is unknown. The aim of this study was to examine the relationship between C pneumoniae seropositivity and AAA rupture. In a case-control study, 119 patients with AAA and 36 matched controls were prospectively investigated with C pneumoniae serology. Patients with ruptured AAA have similar levels of IgG antibodies against C pneumoniae as patients with an electively operated AAA, a small AAA, and controls. In conclusion, this study fails to demonstrate a connection between C pneumoniae seropositivity and AAA rupture.     

Male serum Chlamydia trachomatis IgA and IgG, but not heat shock protein 60 IgG, correlates with negatively affected semen characteristics and lower pregnancy rates in the infertile couple

BACKGROUND: The objective of this study was to evaluate whether serum Chlamydia trachomatis immunoglobulin-A (IgA), IgM and C. trachomatis heat shock protein 60 (CHSP60) IgG are of additional value to C. trachomatis IgG regarding the impact on fecundity in infertile couples, and to relate C. trachomatis serum antibodies to semen characteristics, diagnoses and pregnancy outcome. METHODS: A total of 226 infertile couples, previously tested for C. trachomatis IgG, were tested for C. trachomatis IgA, IgM and CHSP60 IgG, and semen samples from all men were analysed. RESULTS: Chlamydia trachomatis serum IgA in men (but not in women) correlated with reduced chances of achieving pregnancy [p = 0.021, relative risk (RR) =0.65, 95% confidence interval (CI) 0.42-1.005] and in combination with C. trachomatis IgG the chance was further reduced (p =0.001, RR = 0.35, 95% CI 0.15-0.84). Chlamydia trachomatis serum IgA was also significantly correlated with reduced motility of the spermatozoa (-8.7%, p = 0.023), increased number of dead spermatozoa (+10.5%, p = 0.014) and higher prevalence of leucocytes in semen (+122%, p = 0.005), and in combination with C. trachomatis IgG positivity, there was also a decrease in sperm concentration (-35%, p = 0.033), the number of progressive spermatozoa (-14.8%, p = 0.029) and a rise in the teratozoospermia index (+4.4%, p = 0.010). CHSP60 IgG correlated with reduced motility (-5.6%, p = 0.033), and in the women to tubal factor infertility (p = 0.033), but no correlations of C. trachomatis serum IgM or CHSP60 IgG with pregnancy rates were found. CONCLUSIONS: Chlamydia trachomatis serum IgA in the male partner of the infertile couple has an additive value to IgG in predicting pregnancy chances, and serum IgA and IgG are associated with subtle negative changes in semen characteristics.     

Studies on detection of serum IgA and IgG antibodies specific for Chlamydia trachomatis in latent infections in males

We determined the serum concentrations of IgA and IgG antibodies specific for Chlamydia trachomatis (C. trachomatis) by an indirect immunoperoxidase assay (IPAzyme kit, Savyon Diagnostics, Ltd., Bee, Shova, Israel) to evaluate their diagnostic significance in latent infections in males. Forty-five asymptomatic males whose wife or partner was suspected to be infected with C. trachomatis were studied and the incidence of serum IgA (titer greater than or equal to 16) and IgG (titer greater than or equal to 64) antibodies for C. trachomatis was compared with that in a healthy group, a group with non-gonococcal urethritis (NGU) patients. Changes in IgA titer during treatment were also examined. The incidence of IgA and IgG antibodies in the healthy group was found to be 2.4% and 11.9% in males, and 4.8% and 18.1% in females, respectively. In patients whose wife or partner who was positive to C. trachomatis, the incidence of IgA and IgG antibodies was 42.2% and 75.6%, respectively. In the NGU patients the incidence of IgA and IgG antibodies was 56.3% and 62.5%, respectively. The incidence of IgA and IgG antibodies in patients whose wife or partner was antibody-positive were significantly higher (p less than 0.01) than the corresponding value in healthy men and women, but there was no significant difference from NGU patients or the elderly group. The IgA antibody titer during treatment of C. trachomatis infection showed no reduction in some cases. This study revealed frequent latent incidence of C. trachomatis infection in male patients. Determination of C. trachomatis IgA and IgG antibodies is considered to be supplemental for diagnosis of chlamydial latent infections.     

IgG and IgA antibodies specific for Chlamydia trachomatis in acute epididymitis

The possibility of using elevated Chlamydia trachomatis-specific serum IgG and IgA as a screening test for Chlamydia-associated epididymitis was analyzed in 28 acute epididymitis patients and 42 apparently healthy men by the single antigen (L2) immunoperoxidase assay. The prevalence rates of C. trachomatis IgG antibody titer greater than or equal to 64 and elevated C. trachomatis IgG titers (greater than or equal to 128) were significantly higher in the epididymitis patients (75 vs. 40%, p less than 0.01, and 39 vs. 14%, p less than 0.025, respectively) than in controls. The prevalence rate of C. trachomatis IgA antibodies (titer greater than or equal to 8) was significantly higher (p less than 0.001) in epididymitis patients as compared to controls (46 vs. 10%, respectively). The potential application of elevated serum C. trachomatis IgG and IgA antibodies as a noninvasive screening marker in epididymitis patients is discussed.     

Analysis of expansion patterns in 4-4.9 cm abdominal aortic aneurysms

Our objective was to analyze the growth pattern of 4-4.9 cm infrarenal abdominal aortic aneurysms (AAAs). We used an observational, longitudinal, prospective study design. We followed 4-4.9 cm AAAs with 6-monthly abdominal computed tomographic (CT) scans (January 1988-August 2004). AAA growth was defined as an increase in aortic diameter > or =2 mm in each surveillance period. We established the aortic expansion pattern in AAA with three or more CT scans as continuous, discontinuous. The latter includes at least one period of nongrowth (<2 mm/6 months). We studied the influence of cardiovascular risk factors (CVRFs), comorbidity, and AAA anatomical characteristics using the chi-squared test, t-test, life tables, and Kaplan-Meier for statistical analysis. We included 195 patients: 183 (93.8%) men, age 71 +/- 8.3 years (50-90). The follow-up period was 50 +/- 36.4 months (6.5-193.7). The growth pattern (n =131) was continuous in 15 (11.5%) and discontinuous in 116 (88.5%) AAA. The mean expansion rate was higher in AAAs with continuous expansion (7.92 +/- 3.74 vs. 2.74 +/- 2.94 mm/year, p < 0.0001). No CVRFs or comorbidity influenced the expansion pattern (p > 0.05). The eccentric thrombus was associated with a greater incidence of continuous growth (p = 0.05), with no influence of aortic calcification (p > 0.1). The expansion of 4-4.9 cm AAA is mostly irregular and unpredictable. We have not found any modifiable risk factors which influence their growth pattern. The eccentric distribution of the thrombus is associated with continuous expansion.     

Close association of Chlamydia pneumoniae IgA seropositivity by ELISA with the presence of coronary artery stenosis in haemodialysis patients.

BACKGROUND: Traditional risk factors of cardiovascular disease do not fully explain the accelerated atherosclerosis present in patients with end-stage renal disease (ESRD). The goal of this study was to identify the association of clinical and laboratory factors including seropositivity for Chlamydia pneumoniae determined by a specific enzyme-linked immunosorbent assay (ELISA) with the presence of coronary artery disease identified by coronary angiography in ESRD patients. METHODS: We prospectively enrolled 161 consecutive ESRD patients undergoing haemodialysis for >6 months (106 men, 55 women; mean age 63.1+/-10.2 years; mean dialysis duration 91.3+/-90.1 months). All patients underwent coronary angiography within 1 week after blood sampling. The associations of coronary artery disease with clinical parameters including C. pneumoniae IgA and IgG seropositivity were analysed using multiple logistic regression models. RESULTS: Coronary stenosis >50% was found in 102 of 161 haemodialysis patients (63.4%). Of the 102 patients, 75.5% were asymptomatic. Seropositivity for C. pneumoniae IgA was found in patients with coronary stenosis (77 out of 102, 75.5%) more frequently (P<0.001) than in patients without coronary stenosis (10 out of 59, 16.9%). Seropositivity for C. pneumoniae IgA but not IgG was strongly associated with the presence of coronary stenosis in multiple logistic regression analysis (odds ratio, 18.440; 95% confidence interval, 7.500-45.337), independently of the Framingham coronary risk factors, factors peculiar to ESRD or serum C-reactive protein levels. CONCLUSIONS: C. pneumoniae IgA seropositivity determined by ELISA is an independent laboratory factor indicating the presence of coronary artery stenosis in ESRD patients undergoing maintenance haemodialysis.     

Expansion rates and outcomes for the 3.0-cm to the 3.9-cm infrarenal abdominal aortic aneurysm

OBJECTIVE: This study was performed for the determination of the expansion rates and outcomes and for recommendations for the surveillance of the 3.0-cm to 3.9-cm abdominal aortic aneurysm (AAA). DESIGN: The study was observational with data from patients screened with ultrasound scanning for AAA at five Veterans Affairs Medical Centers for enrollment in the Aneurysm Detection and Management Trial. The eligibility requirements included: AAA from 3.0 cm to 3.9 cm in diameter and at least one repeat ultrasound scan more than 90 days after the initial screening. Patients also completed a questionnaire for demographic data and the determination of the presence of risk factors associated with AAA. The study endpoints included: 1, both mean and median expansion rates; 2, moderate expansion (>4 mm/year); 3, no expansion; 4, all causes of death; 5, AAA rupture; 6, expansion to 4 cm or more; 7, expansion to 5.0 cm or more; and 8, operative repair. RESULTS: Ultrasound scan screening results identified 1445 patients with 3.0-cm to 3.9-cm AAAs. Seven hundred ninety men met the ultrasound scan criterion of having at least two ultrasound scan studies during the study period, and these 790 men were used for this study. Mean AAA size was 3.3 cm, with an average follow-up period of 3.89 +/- 1.93 years. The median expansion rate was 0.11 cm/year. Expansion rates were significantly different (P <.001) between 3.0-cm and 3.4-cm cm AAA and 3.5-cm and 3.9-cm AAA. There were no reported AAA ruptures during the study period, although cause of death data were available in only 43% of the patients. Few 3.0-cm to 3.9-cm AAAs expanded to 5.0 cm or more during the study period. The patients with 3.0-cm to 3.9-cm AAAs who underwent operative repair during the study period were younger, had larger initial AAA diameters, and had more rapid expansion rates. CONCLUSION: AAAs of 3.0 cm to 3.9 cm expanded slowly, did not rupture, and rarely had operative repair or expanded to more than 5.0 cm in our study of male patients. Expansion rates and the incidence rate of operative repair are more common in the 3.5-cm to 3.9-cm AAA when compared with the 3.0-cm to 3.4-cm AAA.     

Most patients with abdominal aortic aneurysm are not suitable for endovascular repair using currently approved bifurcated stent-grafts

Strict morphologic criteria must be used for patient selection to achieve durable success with endovascular aortic aneurysm repair (EVAR). The goal of this study was to assess morphologic suitability (MS) of abdominal aortic aneurysms (AAAs) for 2 currently approved bifurcated stent grafts and identify reasons for exclusion from EVAR. The authors reviewed the electronic charts of 1,795 consecutive patients who were diagnosed as having AAA between January 1999 and July 2001 at their institution. Three hundred and twenty patients had an AAA with a diameter of > or = 5.0 cm, measured on computed tomography (CT). The records of 301 patients, 254 men, 47 women, with a mean age of 74 years were available for review, and these patients constituted the study cohort. Criteria used for MS included a proximal neck length > or = 15 mm; neck diameter between 18 and 26 mm; neck angulation < or = 60 degrees ; common or external iliac artery (CIA or EIA) diameters of 7-16 mm and 8-13 mm, respectively, for AneuRx (Medtronic Ave, Santa Rosa, CA) and Ancure (Guidant Cardiac and Vascular Division, Menlo Park, CA) bifurcated grafts. AAAs were suitable for AneuRx device in 14% of patients (43 of 301; 95% CI = 11-19%) and for Ancure in 5% (16 of 301; 95% CI = 3.1-9%). The main reason for exclusion was an inadequate proximal aortic neck (73%). The neck was too short in 49.5%, too wide in 64% and badly angulated in 12% of the patients. Iliac artery morphology precluded EVAR with AneuRx and Ancure devices in 52% and 80%. Both CIAs were too wide for EVAR in 43% and 77%, respectively. When iliac artery diameter < or = 20 mm was accepted, iliac suitability for AneuRx increased from 49% to 70% and overall suitability increased from 14% to 20%. When more permissive criteria were used for MS (neck length > or = 10 mm, neck diameter < or = 30 mm, CIA < or = 20), 39% of patients became candidates for EVAR. More than three fourths of the patients with an AAA > or = 5.0 cm in size, seen in a tertiary referral center, are morphologically not suitable for EVAR using 2 currently approved bifurcated endografts. The main reasons for exclusion are a short or wide proximal aortic neck. Considerable changes in size of the devices and in proximal attachment techniques have to occur before most AAAs will be suitable for EVAR.     

Chlamydia pneumoniae infection and accelerated development of coronary artery disease in patients with chronic renal failure.

AIMS: This study examined the relationship between Chlamydia pneumoniae (C. pneumoniae) infection and the accelerated development of coronary artery disease (CAD) in patients with chronic renal failure (CRF). METHODS: Two-hundred and fourteen patients undergoing coronary angiography, including 67 controls and 147 patients with CAD (97 without CRF and 50 with CRF), were enrolled in this study. Anti-C. pneumoniae specific IgG and IgA antibodies were measured using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Coronary artery disease (expressed as CAD score) was more severe in patients with than without CRF (14.9 +/- 6.0 vs. 11.3 +/- 6.0, p < 0.01). Seropositive rates of IgG and IgA antibodies against C. pneumoniae were higher in all CAD patients than in the controls (76.2% vs. 44.8%, p < 0.001 for IgG; 59.9% vs. 40.3%, p < 0.01 for IgA). In both CAD subgroups, IgG seropositive rates were similarly elevated (82.0% and 73.2% vs. 44.8% for control, p < 0.001, respectively), whereas those of IgA were significantly elevated only in CAD with CRF (68.0% vs. 55.7% for control, p < 0.01). The mean antibody index of IgG was elevated in all CAD patients compared with the controls (1.9 +/- 1.0 vs. 1.3 +/- 0.9, p < 0.0001), but that of IgA was not (1.5 +/- 1.0 vs. 1.2 +/- 0.9). Levels of IgG were elevated in all patients with CAD compared with the control (2.4 +/- 1.1 and 1.8 +/- 1.0 vs. 1.3 +/- 0.9, p < 0.001 and p < 0.001, respectively), whereas those of IgA were elevated only in CAD with CRF (1.8 +/- 1.1 vs. 1.2 +/- 0.9, p < 0.05). Stepwise logistic regression analysis revealed that the elevated IgG antibody index was an independent risk factor for CAD regardless of CRF (odds ratios 1.9, 1.8, and 2.3), whereas the IgA index was a risk factor only in CAD with CRF (odds ratio 1.7). CONCLUSIONS: Chlamydia pneumoniae infection may be related to the accelerated CAD in patients with CRF, which was specifically suggested by an elevated IgA level. In other words, the prevalence of active C. pneumoniae infection is higher in patients with CAD and CRF than that in those with CAD without CRF.     

Inflammation and Chlamydia pneumoniae infection correlate with the severity of peripheral arterial disease.

BACKGROUND: Our aim was to investigate the association of inflammation and Chlamydia pneumoniae infection with the presence and severity of peripheral arterial disease. METHODS: Twenty-eight patients whose initial claudication distance (ICD) in the traditional constant-load treadmill test was <200 m, underwent femoral endarterectomy as part of their interventional treatment (group A). Group B consisted of 23 patients whose ICD was >200 m and were put on medication and a daily exercise program. The control group consisted of 30 non-vascular patients of the Ophthalmology Department (group C). We measured the levels of C-reactive protein, fibrinogen, vascular cell adhesion molecule-1 and tumor necrosis factor-alpha, and the titers of IgA and IgG antibodies against C. pneumoniae in the serum of all the patients. Finally, the atheromas and vein segments of group A patients, were immunohistochemically (IHC) examined for the presence of C. pneumoniae. RESULTS: Peripheral arterial disease (PAD) patients, had significantly higher CRP (p=0.026) and anti-Cp IgA levels (p=0.001) when compared to control subjects, after a multiple linear regression analysis. The odds ratio for the prevalence of femoral atherosclerosis was 3.16 for IgA seropositive patients (CI 1.15-8.67). When comparing group A and group B patients, CRP (p=0.003) and IgA (p=0.011), were significantly correlated with severe PAD. Group A patients with positive immunohistochemical examination of the plaque, had higher anti-Cp IgA levels (p=0.023) and TNF-alpha values (p=0.031), compared to the IHC negative patients. C. pneumoniae was detected in 50% of the femoral atheromas, but in only 3.6% of the veins. CONCLUSION: This study supports the hypothesis that inflammation (CRP) and chronic C. pneumoniae infection (IgA seropositivity), have an important role in lower limb atherosclerosis and correlate with the severity of the disease.     

Influence of age, aneurysm size, and patient fitness on suitability for endovascular aortic aneurysm repair

Prior to approval by the U.S. Food and Drug Administration of larger endografts (main body diameters up to 36 mm), small abdominal aortic aneurysms (AAAs, <5.5 cm) were shown to be more suitable for endovascular repair (EVAR) than large AAAs (> or =5.5 cm). The purpose of this study was to assess changes in EVAR suitability with the potential use of larger endografts in unselected consecutive patients. The influence of age, aneurysm size, and patient fitness on EVAR suitability was also assessed. We studied 186 male patients referred for evaluation of nonruptured AAAs who underwent contrast-enhanced computed tomographic scans with three-dimensional reconstructions. Morphologicall AAA features and neck characteristics were measured according to Society for Vascular Surgery reporting standards to determine EVAR suitability. Patient fitness for repair was assessed using the customized probability index, a validated fitness score for vascular surgery procedures. Suitability for EVAR was determined by neck anatomy, iliac artery morphology, and total aortic aneurysm angulation and tortuosity according to the clinicians' experience and current practice. The median age of the study cohort was 72 years (interquartile range [IQR] 65-79 years). The median maximum AAA diameter was 5.4 cm (IQR 4.1-5.9). Median fitness score was +7 (IQR -7 to +14). EVAR suitability for large AAAs significantly increased with larger endografts (35-63%, p<0.001). Changes in EVAR suitability for small AAAs were not significant (69-75%, p=0.06). Maximum AAA diameter was not an independent predictor for EVAR suitability with larger endografts after adjusting for neck anatomy. Aortic neck length (odds ratio [OR]=1.2, 95% confidence interval [CI] 1.1-1.2) and diameter (OR=0.78, 95% CI 0.63-0.96) were the only independent predictors for EVAR suitability with larger endografts. Age, AAA size, and fitness did not differ between patients suitable and unsuitable for EVAR with larger endografts. In conclusion, introduction of larger endografts (up to 36 mm in main body diameter) in the United States has resulted in significantly increased anatomic suitability for EVAR for large AAAs. Conversely, suitability has not significantly changed for small AAAs. Overall, EVAR suitability is not influenced by age, aneurysm size, or patient fitness.     

Effects of Statin Therapy on Abdominal Aortic Aneurysm Growth: A Meta-analysis and Meta-regression of Observational Comparative Studies

OBJECTIVE: To determine whether statin therapy reduces the growth rate of small abdominal aortic aneurysms (AAAs). DESIGN: A meta-analysis and a meta-regression of comparative studies. MATERIALS: Eligible studies were randomized controlled trials or observational comparative studies of statin therapy versus placebo or no statin, enrolling individuals with small (<55?mm in diameter) AAAs and reporting AAA growth rate as an outcome. METHODS: Study-specific estimates (standardized mean differences [SMDs]) were combined in the fixed- and random-effects model. RESULTS: Seven adjusted and 4 unadjusted observational comparative studies enrolling 4647 patients with a small AAA were identified. Pooled analysis of all 11 studies suggested a significant reduction in AAA growth rate among patients assigned to statin therapy versus no statin (SMD,?-0.420; 95% confidence interval [CI],?-0.651 to?-0.189). Combining the 7 high-quality studies providing adjusted data for growth rates generated an attenuated but still statistically significant result favoring statin therapy (SMD,?-0.367; 95% CI,?-0.566 to?-0.168). The meta-regression coefficient for the baseline diameter was statistically significant (-0.096; 95% CI,?-0.132 to?-0.061). CONCLUSION: Statin therapy is likely effective in prevention of the growth of small AAAs, and may be more beneficial as the baseline diameter increases.     

Relatively high pulmonary and cardiovascular mortality rates in screening-detected aneurysmal patients without previous hospital admissions.

BACKGROUND: Men with abdominal aortic aneurysm (AAA) who are not hospitalised for pulmonary and cardiovascular diseases may have higher mortality due to such disorders. MATERIAL AND METHODS: Previous discharge diagnoses and causes of death were collected for 4,816 men aged 64-73 years attending mass screening for AAA. Of these, 191 (4%) had an AAA. Overall, cardiovascular- and pulmonary-disease-specific mortality was compared for men with and without AAA stratified for earlier pulmonary or cardiovascular hospitalisations by Cox's proportional hazards regression while adjusting for age. Absolute risk differences after five years were calculated by life table analysis. RESULTS: The median observation time was 63 months. 362 men died from cardiovascular causes other than AAA, and 144 died from pulmonary causes. The cardiovascular mortality was significantly higher in aneurysm patients without previous related hospitalisation (HR=4.35, 95% CI: 2.73-6.94, P<0.001) with an absolute mortality difference after 5 years of 16.3% (95% CI: 10.2-22.5%). Pulmonary-cause mortality was higher among men with AAA both with and without previous hospitalisation for pulmonary causes (HR=3.05; 95% CI: 1.19-7.83, P=0.020, and HR=3.29; 95% CI: 1.78-6.08, P<0.001, respectively). CONCLUSIONS: Men with AAA who had not been hospitalised for cardiovascular diseases have more than four times higher cardiovascular mortality. Studies of cohorts being offered relevant prophylaxis may clarify the potential benefits of general preventive actions.