Influence of lipoprotein(a) on restenosis after femoropopliteal percutaneous transluminal angioplasty in Type 2 diabetic patients

C-reactive Protein, Free Fatty Acid, and Uric Acid as Predictors of Adverse Events after Endovascular Revascularization of Arterial Femoropopliteal Occlusion Lesions

OBJECTIVES

This study aimed to investigate the relationship between pre-procedure high-sensitivity C-reactive protein (hsCRP), free fatty acid (FFA), and uric acid (UA) levels and post-procedure mortality and morbidity of endovascular revascularization of arterial femoropopliteal occlusion lesions.

METHODS

This was a retrospective review of clinical data retrieved from a prospectively held database in Peking Union Medical College Hospital. A total of 71 Patients who underwent endovascular treatment (EVT) for femoropopliteal occlusive disease between January 1, 2014 and November 1, 2017, were included in this study. Endpoints were defined as major adverse limb events (MALE; target vessel revascularization, amputation, or disease progression) and major adverse cardiovascular events (MACE; stroke, myocardial infarction, or all-cause death) during the entire follow-up period. Univariate and multivariate Cox proportional hazards regression models were used to evaluate the relationship of elevated biomarker levels (hsCRP, FFA and UA, measured by immunoturbidimetry assay, enzymatic assay and enzymatic assay, respectively) to MALE and MACE outcomes.

RESULTS

Seventy-one patients (72 limbs) with sufficient follow-up information were included in the analysis. The mean age was 69.7 ± 8.6 years; 21.1% were female. The Rutherford class of target limbs were ≥ 3. The median follow-up was 36 (range 18-59 months). Univariate analyses revealed that patients with elevated hsCRP levels had an increased risk of MALE (hazard ratio [HR], 2.682; 95% confidence interval [CI], 1.281-5.617, P = 0.009). High FFA levels were associated with an increased risk of MALE (HR, 2.658; 95% CI, 1.075-6.573; P = 0.034). Multivariate analyses demonstrated that elevated hsCRP values (HR, 4.015; 95% CI, 1.628-10.551; P = 0.003) and FFA value (HR, 3.034; 95% CI, 1.102-8.354; P = 0.032) were both significantly associated with increased MALE. Elevated UA levels predicted MACE in the presence of confounders (HR, 11.446; 95% CI, 1.367-95.801 P = 0.023).

CONCLUSION

Pre-procedure hsCRP and FFA levels could serve as predictors of adverse events after EVT in patients with arterial femoropopliteal occlusive disease. The role of UA in MACE may warrant further investigation, because the correlation is not as powerful as the other two in the study.

Long-term Effect of Glimepiride and Rosiglitazone on Non-conventional Cardiovascular Risk Factors in Metformin-treated Patients Affected by Metabolic Syndrome: A Randomized, Double-blind Clinical Trial

We evaluated the effect of glimepiride plus metformin and rosiglitazone plus metformin on glucose, and on cardiovascular risk parameters such as lipoprotein(a) (Lp[a]) and homocysteine (HCT) in patients with type 2 diabetes and metabolic syndrome. Ninety-nine patients in the multicentre, randomized, double-blind study took metformin (1500 mg/day) plus glimepiride (2 mg/day) or rosiglitazone (4 mg/day) for 12 months. Changes in body mass index, glycosylated haemoglobin (HbA1c), Lp(a) and HCT were primary efficacy variables. Fasting plasma glucose (FPG), post-prandial plasma glucose (PPG) and homeostasis model assessment index were also used to assess efficacy. On average, HbA1c decreased by 9.1% and 8.1%, FPG decreased by 7.3% and 10.9%, and PPG decreased by 7.6% and 10.5%, respectively, in the glimepiride and rosiglitazone groups after 12 months. Patients receiving rosiglitazone experienced more rapid improvement in glycaemic control than those on glimepiride, and showed a significant improvement in insulin resistance-related parameters. There was a statistically significant decrease in basal homocysteinaemia in glimepiride-treated patients (−27.3%), but not in rosiglitazone-treated patients. Rosiglitazone plus metformin significantly improved long-term control of insulin resistance-related parameters compared with glimepiride plus metformin, although glimepiride treatment was associated with a slight improvement in cholesterolaemia, not observed in the rosiglitazone-treated patients, and with significant improvements in non-traditional risk factors for cardiovascular disease, such as basal homocysteinaemia and plasma Lp(a) levels.

Small dense low density lipoprotein particles are associated with poor outcome after angioplasty in peripheral artery disease

Purpose

In patients suffering from symptomatic peripheral artery disease (PAD), percutaneous revascularization is the treatment of choice. However, restenosis may occur in 10 to 60% in the first year depending on a variety of factors. Small dense low density lipoprotein (sdLDL) particles are associated with an increased risk for cardiovascular events, but their role in the process of restenosis is not known. We conducted a prospective study to analyze the association of sdLDL particles with the outcome of balloon angioplasty in PAD. The composite primary endpoint was defined as improved walking distance and absence of restenosis.

Methods

Patients with angiographically documented PAD of the lower extremities who were scheduled for lower limb revascularization were consecutively recruited for the study. At baseline and at three month follow-up triglyceride, total cholesterol, LDL size and subclasses and HDL cholesterol and ankle-brachial index (ABI) were measured. Three months after the intervention duplex sonography was performed to detect restenosis.

Results

Sixty-four patients (53% male) with a mean age of 68.6±9.9 years were included. The proportion of small- dense LDL particles (class III and IV) was significantly lower (33.1±11.0% vs. 39.4±12.1%, p = 0.038) in patients who reached the primary end-point compared with those who did not. Patients with improved walking distance and without restenosis had a significantly higher LDL size at baseline (26.6±1.1 nm vs. 26.1±1.1 nm, p = 0.046) and at follow-up (26.7±1.1 nm vs. 26.2±0.9 nm, p = 0.044) than patients without improvement.

Conclusions

Small-dense LDL particles are associated with worse early outcome in patients undergoing percutaneous revascularization for symptomatic PAD.

Peripheral arterial disease in diabetes--a review

Diabetic patients are at high risk for peripheral arterial disease (PAD) characterized by symptoms of intermittent claudication or critical limb ischaemia. Given the inconsistencies of clinical findings in the diagnosis of PAD in the diabetic patient, measurement of ankle-brachial pressure index (ABI) has emerged as the relatively simple, non-invasive and inexpensive diagnostic tool of choice. An ABI < 0.9 is not only diagnostic of PAD even in the asymptomatic patient, but is also an independent marker of increased morbidity and mortality from cardiovascular diseases. With better understanding of the process of atherosclerosis, avenues for treatment have increased. Modification of lifestyle and effective management of the established risk factors such as smoking, dyslipidaemia, hyperglycaemia and hypertension retard the progression of the disease and reduce cardiovascular events in these patients. Newer risk factors such as insulin resistance, hyperfibrinogenaemia, hyperhomocysteinaemia and low-grade inflammation have been identified, but the advantages of modifying them in patients with PAD are yet to be proven. Therapeutic angiogenesis, on the other hand, represents a promising therapeutic adjunct in the management of PAD in these patients. Outcomes after revascularization procedures, such as percutaneous transluminal angioplasty and surgical bypasses in diabetic patients, are poorer, with increased perioperative morbidity and mortality compared with that in non-diabetic patients. Amputation rates are higher due to the distal nature of the disease. Efforts towards increasing awareness and intensive treatment of the risk factors will help to reduce morbidity and mortality in diabetic patients with PAD.

Lipoprotein(a) and other serum lipid subfractions influencing primary patency after infrainguinal percutaneous transluminal angioplasty

PURPOSE

To evaluate the influence of serum lipid subfraction concentrations on arterial patency after percutaneous transluminal angioplasty (PTA) in patients with infrainguinal peripheral artery occlusive disease (PAOD).

METHODS

From January 2007 to June 2008, a prospective study was conducted involving 39 patients (29 men; mean age 68.6+/-10.0 years) with infrainguinal PAOD in 41 limbs who had preprocedural lipid assessment and underwent successful PTA (<30% residual stenosis). Patient demographics, Fontaine clinical stage classification, Texas University Classification of ulcers, coexisting medical conditions, endovascular procedures, and lipid profiles were collected in a database. Follow-up included clinical and duplex ultrasound evaluation at discharge and at 1, 3, 6, and 12 months. To analyze any correlation between various lipid subfractions and the loss of primary patency (Cox proportional hazards modeling), the patients were dichotomized into high and low groups according to these thresholds: LDL-C >100 mg/dL, HDL-C <40 mg/dL, Lp(a) >30 mg/dL, and an Apo(B)/Apo(A) ratio >0.8 mg/dL.

RESULTS

Mean follow-up was 7.5 months (range 3-12). After 1, 3, and 6 months, the primary patency rates by Kaplan-Meier analysis were 94.9%, 73.7%, and 64.1%, respectively. Restenosis at 6 months was significantly related to female gender (HR 95.9, 95% CI 6.8 to 1352.5, p = 0.001), HDL-C <40 mg/dL (HR 86.9, 95% CI 6.4 to 1183.1, p = 0.001), LDL-C >100 mg/dL (HR 9.6, 95% CI 1.6 to 57.4, p = 0.013), and Lp(a) >30 mg/dL (HR 6.1, 95% CI 1.4 to 26.3, p = 0.016).

CONCLUSION

Our results suggest that Lp(a), LDL-C, and HDL-C are independent risk factors for restenosis after infrainguinal PTA.

Lipoprotein (a) in patients with spontaneous venous thromboembolism

INTRODUCTION

Elevated lipoprotein (a) (Lp (a)) has been established as a risk factor of coronary heart disease and stroke. Findings concerning the risk of venous thromboembolism (VTE) in adults are contradictory. The aim of our study was to investigate, whether elevated Lp (a) levels are an independent risk factor of spontaneous symptomatic venous thromboembolism (VTE). Our study was further designed to detect differences in risk profiles between thrombosis patients with and without symptomatic PE.

MATERIALS AND METHODS

We investigated Lp (a) in 128 patients with spontaneous symptomatic deep vein thrombosis (DVT, group 1), 105 with spontaneous symptomatic pulmonary embolism with or without DVT (PE, group 2) and 122 healthy controls. Lp (a) was measured with an immunoturbidimetric assay (Tina-quant(R), Roche, Grenzach-Wyhlen, Germany) on a Hitachi-Modular system.

RESULTS

Lp (a) levels (mg/L) were not significantly different among groups, median levels (25th-75th percentiles) were 170 (51-386) in group 1, 140 (<20-427) in group 2 and 126 (54-331) in controls, respectively. As continuous variable, odds ratios for VTE for a 100 mg/L increase of Lp (a) were 1.1 [95% confidence interval 0.98-1.2] for group 1 versus controls and 1.1 [0.95-1.2] for group 2 versus controls. The prevalence of Lp (a) above 300 mg/L was not significantly different among patients and controls (group 1: 30%, group 2: 32% and controls: 25%, p=0.4, p=0.2, respectively).

CONCLUSIONS

In conclusion we found no association between Lp (a) and VTE regardless whether DVT occurred together with PE or not.

Metformin–pioglitazone and metformin–rosiglitazone effects on non-conventional cardiovascular risk factors plasma level in type 2 diabetic patients with metabolic syndrome

BACKGROUND AND OBJECTIVE

Metformin is considered the gold standard for type 2 diabetes treatment as monotherapy and in combination with sulphonylureas and insulin. The combination of metformin with thiazolidinediones is less well studied. The aim of the present study was to assess the differential effect, and tolerability, of metformin combined with pioglitazone or rosiglitazone on glucose, coagulation and fibrinolysis parameters in patients with type 2 diabetes mellitus and metabolic syndrome.

METHODS

This 12-month, multicentre, double-blind, randomized, controlled, parallel-group trial was conducted at three study sites in Italy. We assessed patients with type 2 diabetes mellitus (duration >or=6 months) and with metabolic syndrome. All patients were required to have poor glycaemic control with diet, or experienced adverse effects with diet and metformin, administered up to the maximum tolerated dose. Patients were randomized to receive either pioglitazone or rosiglitazone self-administered for 12 months. We assessed body mass index (BMI), glycaemic control [glycosylated haemoglobin (HbA(1c)), fasting and postprandial plasma glucose and insulin levels (FPG, PPG, FPI, and PPI respectively), homeostasis model assessment (HOMA) index], lipid profile [total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein-cholesterol (HDL-C) and triglycerides (TG)], lipoprotein (a) [Lp(a)] and homocysteine (HCT) at baseline and at 3, 6, 9 and 12 months of treatment.

RESULTS AND DISCUSSION

No BMI change was observed at 3, 6, 9 and 12 months in either group. Significant HbA(1c) decreases were observed at 9 and 12 months in both groups. After 9 and 12 months, mean FPG and PPG levels decreased in both groups. Decreases in FPI and PPI were observed at 9 and 12 months compared with the baseline in both groups. Furthermore, in both groups, the HOMA index improved but only at 12 months. Significant TC, LDL-C, HDL-C, TG improvement was present in the pioglitazone group at 12 months compared with the baseline values, and these variations were significantly different between groups. No TC, LDL-C, TG improvement was present in the rosiglitazone group after 12 months. Significant Lp(a) and HCT improvement was present in the pioglitazone group at 12 months compared with the baseline values, and Lp(a) change was significant compared with the rosiglitazone group. Significant HCT decrease was observed in the rosiglitazone group at the end of the study. In our type 2 diabetic patients, both drugs were safe and effective for glycaemic control and improving HCT plasma levels. However, long-term treatment with metformin plus pioglitazone significantly reduced Lp(a) plasma levels, whereas metformin + rosiglitazone did not.

CONCLUSION

For patients with type 2 diabetes mellitus and metabolic syndrome, combined treatment with metformin and rosiglitazone or pioglitazone is safe and effective, However, the pioglitazone combination also reduced the plasma Lp(a) levels whereas the rosiglitazone combination did not.

Effects of 1 Year of Treatment with Pioglitazone or Rosiglitazone Added to Glimepiride on Lipoprotein (a) and Homocysteine Concentrations in Patients with Type 2 Diabetes Mellitus and Metabolic Syndrome: A Multicenter, Randomized, Double-Blind, Controlled Clinical Trial

BACKGROUND

Although the metabolic effects of the thiazolidinediones have been well studied, there is a lack of comparative data on their effects on certain cardiovascular risk factors, such as elevated plasma levels of lipoprotein (a) (Lp[a]) and homocysteine (Hcy).

OBJECTIVE

This study compared the effects of pioglitazone or rosiglitazone added to glimepiride on a range of lipid parameters, focusing on Lp(a) and Hcy, in patients with type 2 diabetes mellitus and the metabolic syndrome.

METHODS

This was a multicenter, randomized, controlled, double-blind study in patients with type 2 diabetes and the metabolic syndrome (hypertension [>or=130/85 mm Hg]) and triglyceridemia (>or=150 mg/dL). In addition to glimepiride 4 mg/d, patients received pioglitazone 15 mg QD or rosiglitazone 4 mg QD for 1 year. The primary efficacy variables were change from baseline in body mass index (BMI), glycosylated hemoglobin (HbA(1c)), Lp(a), and Hey. Secondary efficacy measures were changes in fasting plasma glucose (FPG) and postprandial plasma glucose (PPG) concentrations, fasting and postprandial insulin concentrations (FPI and PPI, respectively), the Homeostasis Model Assessment index, and the lipid profile (total cholesterol [TC], low-density lipoprotein cholesterol [LDL-C], high-density lipoprotein cholesterol [HDL-C], and triglycerides). All these parameters were measured after a 12-hour fast every 3 months for 1 year. Tolerability was assessed based on reported adverse events and laboratory abnormalities at each study visit.

RESULTS

Ninety-one white patients with type 2 diabetes and the metabolic syndrome were enrolled, and 87 completed the study (43 men, 44 women; mean [SD] age, 53 [6] years; mean weight, 68.4 [3.3] kg). Mean baseline values for BMI and HbA(1c) were 24.3 (0.8) kg/m(2) and 8.1 % (0.8 %), respectively. At the end of 1 year, both treatment groups had significant increases from baseline in BMI (4.9% glimepiride + pio glitazone, 6.2% glimepiride + rosiglitazone; P < 0.05). Glimepiride + pioglitazone was associated with the following percent improvements from baseline in measures of glycemic control: -17.1% in HbA(1c), -19.3% in FPG, -17.8% in PPG, -40.1% in FPI, and -22.6% in PPI (all, P < 0.01). The corresponding percent improvements from baseline with glimepiride + rosiglitazone were -16.3%, -19.9%, -15.0%, -44.8%, and -22.1% (all, P < 0.01). There were no significant differences between treatment groups in any of these parameters. The pioglitazone group had significant improvements from baseline in TC (-11.1%), LDL-C (-12.0%), HDL-C (15.0%), and triglycerides (-22.4%) [corrected] (all, P < 0.05), whereas the rosiglitazone group had significant increases in TC (14.9%), LDL-C (16.5%), and triglycerides (17.9%) (all, P < 0.05); the difference between pioglitazone and rosiglitazone was statistically significant (P < 0.05). The change from baseline in Lp(a) was significant in the pioglitazone group, both relative to baseline and compared with the rosiglitazone group (-19.7% vs 0.5%, respectively; P < 0.05 vs baseline and vs rosiglitazone). Changes from baseline in Hey were significant in both the pioglitazone and rosiglitazone groups (-20.2% and -25.0%, respectively; P < 0.05), with no significant difference between groups. Both treatments were well tolerated, and no patients had significant changes in transaminases.

CONCLUSIONS

In these patients with type 2 diabetes and the metabolic syndrome, the combinations of glimepiride with pioglitazone and glimepiride with rosiglitazone produced significant improvements in measures of glycemic control, plasma lipids, and homocysteinemia. One year of treatment with the pioglitazone combination was associated with significantly reduced plasma Lp(a) levels compared with the rosiglitazone combination.

Lipoprotein(a), type 2 diabetes and vascular risk in coronary patients

BACKGROUND

Lipoprotein(a) [Lp(a)] is an important cardiovascular risk factor in the general population. However, prospective data on the vascular risk conferred by Lp(a) in patients with diabetes mellitus are scarce and controversial. It is not known whether the diabetic state affects the association of Lp(a) with vascular events among coronary patients.

DESIGN

We measured Lp(a) in 587 consecutive patients undergoing coronary angiography for the evaluation of coronary artery disease. The incidence of vascular events was recorded over 4 years.

RESULTS

At baseline, Lp(a) was significantly lower in patients with type 2 diabetes (T2DM) (n = 136) than in nondiabetic individuals (11 (0.8-30) mg dL(-1) vs. 16 (0.8-51) mg dL(-1); P = 0.025). Prospectively, Lp(a) was a strong and independent predictor of vascular events in nondiabetic patients (standardized adjusted hazard ratio (HR) = 1.461 (1.121-1.904); P = 0.005), but not in patients with T2DM [HR = 0.812 (0.539-1.223); P = 0.320]. An interaction term diabetes x Lp(a) was significant (P = 0.008), indicating that Lp(a) was a significantly stronger predictor of vascular events in nondiabetic patients than in patients with T2DM.

CONCLUSIONS

Lp(a) in diabetic coronary patients is low and not associated with the incidence of vascular events. Although measurement of Lp(a) provides useful information in nondiabetic coronary patients, it is of little value in coronary patients with T2DM.

The effect of L-carnitine on plasma lipoprotein(a) levels in hypercholesterolemic patients with type 2 diabetes mellitus

BACKGROUND

A previous study has demonstrated that L-carnitine reduces plasma lipoprotein(a) (Lp[a]) levels in patients with hypercholesterolemia.

OBJECTIVE

To test a tolerable Lp(a)-reducing agent in diabetic patients, we assessed the effect of a dietary supplementation of L-carnitine on plasma lipid levels, particularly Lp(a), of patients with type 2 diabetes mellitus (DM) and hypercholesterolemia.

METHODS

In this 6-month, randomized, double-masked, placebo-controlled clinical trial, patients were enrolled, assessed, and followed up at the Diabetic and Metabolic Diseases Center of the Department of Internal Medicine and Therapeutics at the University of Pavia, Pavia, Italy. All study patients had newly diagnosed type 2 DM that was managed through dietary restriction alone throughout the study, as well as hypercholesterolemia. Patients were randomized to 1 of 2 groups. One group received L-carnitine, one 1-g tablet BID. The other group received a corresponding placebo. We assessed body mass index, fasting plasma glucose, postprandial plasma glucose, glycosylated hemoglobin, fasting plasma insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, apolipoprotein (apo) A-I, apo B, and Lp(a) at baseline and at 1, 3, and 6 months of treatment.

RESULTS

This study included 94 patients. The treatment group included 24 men and 22 women (mean [SD] age, 52 [6] years). The placebo group included 23 men and 25 women (mean [SD] age, 50 [7] years). The baseline characteristics of the groups did not differ significantly. The mean (SD) body weight, height, and body mass index were 78.2 (5.8) kg, 1.70 (0.04) m, and 27.3 (2.5) kg/m(2), respectively, in the L-carnitine group and 77.6 (6.4) kg, 1.71 (0.05) m, and 26.8 (2.2) kg/m(2), respectively, in the placebo group. In the treatment group, Lp(a) was significantly reduced at 3 and 6 months compared with baseline (P < 0.05) and P < 0.01, respectively). We observed a significant improvement after 6 months (P < 0.05) in the Lp(a) value in patients taking L-carnitine compared with those taking placebo. Between-group differences in other variables did not reach a level of significance at months 3 and 6. No drug-related adverse events were reported or observed.

CONCLUSION

In this preliminary study, after 3 and 6 months, L-carnitine significantly lowered the plasma Lp(a) level compared with placebo in selected hypercholesterolemic patients with newly diagnosed type 2 DM.