Prospective study of lipoprotein(a) as a risk factor for deteriorating renal function in type 2 diabetic patients with overt proteinuria

Association between Lipoprotein(a) and diabetic nephropathy in patients with type 2 diabetes

Background

Diabetic nephropathy (DN) is one of the most prevalent and severe microvascular complications of type 2 diabetes (T2DM). However, little is currently known about the pathogenesis and its associated risk factors in DN. The present study aims to investigate the potential risk factors of DN in patients with T2DM.

Methods

A total of 6,993 T2DM patients, including 5,089 participants with DN and 1,904 without DN, were included in this cross-sectional study. Comparisons between the two groups (DN vs. non-DN) were carried out using Student's t-test, Mann-Whitney U-test, or Pearson's Chi-squared test. Spearman's correlation analyses were performed to assess the correlations of serum lipids and indicators of renal impairment. Logistic regression models were applied to assess the relationship between blood lipid indices and the presence of DN.

Results

T2DM patients with DN were older, and had a longer duration of diagnosed diabetes compared to those without DN. Of note, the DN patients also more likely develop metabolic disorders. Among all serum lipids, Lipoprotein(a) [Lp(a)] was the most significantly correlated indicators of renal impairment. Moreover, univariate logistic regression showed that elevated Lp(a) level was associated with an increased risk of DN. After adjusted for confounding factors, including age, gender, duration of T2DM, BMI, SBP, DBP and lipid-lowering drugs usage, Lp(a) level was independently positively associated with the risk of DN [odds ratio (OR):1.115, 95% confidence interval (CI): 1.079-1.151, P=6.06×10-11].

Conclusions

Overall, we demonstrated that serum Lp(a) level was significantly positively associated with an increased risk of DN, indicating that Lp(a) may have the potential as a promising target for the diagnosis and treatment of diabetic nephropathy.

Is inverse association between lipoprotein(a) and diabetes mellitus another paradox in cardiometabolic medicine?

INTRODUCTION

The impact of Type II Diabetes mellitus (T2DM) on cardiovascular disease (CVD) is well-established, while lipoprotein(a) [Lp(a)] has recently emerged as a recognized CVD risk factor. The rising prevalence of T2DM resulting from modern lifestyles and the development of specific Lp(a)-lowering agents brought the association between T2DM and Lp(a) in the forefront.

AREAS COVERED

Despite advancements in T2DM treatment, diabetic patients remain at very-high risk of CVD. Lp(a) may, to some extent, contribute to the persistent CVD risk seen in diabetic patients, and the coexistence of T2DM and elevated Lp(a) levels appears to synergistically amplify overall CVD risk. The relationship between T2DM and Lp(a) is paradoxical. On one hand, high Lp(a) plasma concentrations elevate the risk of diabetic microvascular and macrovascular complications. On the other hand, low Lp(a) plasma concentrations have been linked to an increased risk of developing T2DM.

EXPERT OPINION

Comprehending the association between T2DM and Lp(a) is critical due to the pivotal roles both entities play in overall CVD risk, as well as the unique aspects of their relationship. The mechanisms underlying the inverse association between T2DM and Lp(a) remain incompletely understood, necessitating further meticulous research.

Association Between Lipoprotein (A) and Diabetic Nephropathy in Patients With Type 2 Diabetes Mellitus: A Meta-Analysis

BACKGROUND

Lipoprotein (a) [Lp (a)] has been well recognized as a risk factor of cardiovascular disease. However, the association between serum Lp (a) and diabetic nephropathy in patients with type 2 diabetes mellitus (T2DM) remains unknown. We performed a meta-analysis to comprehensively evaluate the above association.

METHODS

Observational studies aiming to evaluate the independent association between serum Lp (a) and diabetic nephropathy in T2DM patients were identified by systematic search of PubMed and Embase databases. A random-effect model which incorporated the potential intra-study heterogeneity was used for the meta-analysis.

RESULTS

Eleven observational studies with 9304 T2DM patients were included. Results showed that compared to those with the lowest Lp (a), patients with the highest Lp (a) level had higher odds of diabetic nephropathy (adjusted odds ratio [OR]: 1.63, 95% confidence interval [CI]: 1.25-2.14, I² = 54%, P < 0.001). Meta-analysis of studies in which Lp (a) was presented as continuous variables showed consistent result (adjusted OR: 1.13 for 1 mg/dl increment of Lp (a), 95% CI: 1.03-1.24, I2 = 36%, P = 0.008). Subgroup analyses showed that study characteristics such as definitions of diabetic nephropathy and study design did not significantly affect the association (P for subgroup difference all > 0.05).

CONCLUSIONS

Higher serum Lp (a) in patients with T2DM is independently associated with higher odds of diabetic nephropathy. Large scale prospective cohort studies are needed to validate this finding. Moreover, the potential influence of Lp (a) lowering on renal function in T2DM patients may be further investigated.

Serum lipoprotein (a) associates with a higher risk of reduced renal function: a prospective investigation

Lipoprotein (a) [Lp(a)] is a well-known risk factor for cardiovascular disease, but analysis on Lp(a) and renal dysfunction is scarce. We aimed to investigate prospectively the association of serum Lp(a) with the risk of reduced renal function, and further investigated whether diabetic or hypertensive status modified such association. Six thousand two hundred and fifty-seven Chinese adults aged ≤40 years and free of reduced renal function at baseline were included in the study. Reduced renal function was defined as estimated glomerular filtration rate <60 ml/min/1.73 m2 During a mean follow-up of 4.4 years, 158 participants developed reduced renal function. Each one-unit increase in log10-Lp(a) (milligrams per deciliter) was associated with a 1.99-fold (95% CI 1.15-3.43) increased risk of incident reduced renal function; the multivariable-adjusted odds ratio (OR) for the highest tertile of Lp(a) was 1.61 (95% CI 1.03-2.52) compared with the lowest tertile (P for trend = 0.03). The stratified analysis showed the association of serum Lp(a) and incident reduced renal function was more prominent in participants with prevalent diabetes [OR 4.04, 95% CI (1.42-11.54)] or hypertension [OR 2.18, 95% CI (1.22-3.89)]. A stronger association was observed in the group with diabetes and high Lp(a) (>25 mg/dl), indicating a combined effect of diabetes and high Lp(a) on the reduced renal function risk. An elevated Lp(a) level was independently associated with risk of incident reduced renal function, especially in diabetic or hypertensive patients.

Lipoprotein(a)and renal function decline, cardiovascular disease and mortality in type 2 diabetes and microalbuminuria

AIMS

Lipoprotein(a)(Lp(a)) has emerged as an independent risk marker for cardiovascular disease (CVD) in the general population and among persons with existing CVD. We investigated associations between serum Lp(a)concentrations and renal function decline, incident CVD and all-cause mortality in individuals with type 2 diabetes (T2D) and microalbuminuria.

METHODS

Prospective study including 198 individuals with T2D, microalbuminuria and no CVD. Yearly p-creatinine was measured after baseline in 176 of the participants. The renal endpoint was defined as decline in eGFR of >30% from baseline. CVD events and mortality were tracked from national registries. Cox regression analyses were applied both unadjusted and adjusted for traditional risk factors (sex, age, systolic blood pressure, LDL-cholesterol, smoking, HbA_1c, creatinine and urinary albumin creatinine ratio (UAER)).

RESULTS

Baseline mean (SD) age was 59 (9)years, eGFR 89 (17) mL/min/1.73 m², 77% were male, and median [IQR] UAER was 103 [38-242] mg/24-h. Median Lp(a)was 8.04 [3.42-32.3] mg/dL. Median follow-up was 6.1 years; 38 CVD events, 26 deaths and 43 renal events were recorded. For each doubling of baseline Lp(a), the following hazard ratios (95% confidence intervals) were found before and after adjustment respectively: 0.98 (0.84-1.15) and 1.01 (0.87-1.18) for decline in eGFR > 30%, 0.96 (0.81-1.13) and 0.99 (0.82-1.18) for CVD events, 1.04 (0.85-1.27) and 1.06 (0.87-1.30) for all-cause mortality.

CONCLUSIONS

In this cohort of individuals with T2D and microalbuminuria, the baseline concentration of Lp(a)was not a risk marker for renal function decline, CVD events or all-cause mortality.

Diabetic dyslipidaemia

PURPOSE OF REVIEW

The purpose is to discuss recent developments in the understanding of lipoprotein metabolism in diabetes, the cardiovascular risk associated with both type 1 and type 2 diabetes, recently published guidelines on the management of this risk, concerns over the use of statin treatment in diabetes, and other therapeutic options.

RECENT FINDINGS

Diabetic dyslipidaemia can be gross with massive hypertriglyceridemia, or subtle with a lipid profile which would be regarded as normal in a nondiabetic patient, but which hides underlying increases in atherogenic subfractions of LDL (e.g., small dense LDL, glycated LDL) and remnant lipoproteins. Statins can decrease these without the clinician being aware from routine biochemistry. In type 2 diabetes, HDL cholesterol levels are often reduced, whereas in type 1, insulin can raise HDL, but its antiatherogenic properties are compromised. Dyslipidaemia and hypertension predate the onset of glycaemia of diabetic proportions (metabolic syndrome). Obese people can thus die of diabetes before they develop it. Obesity should be prevented and treated. Statins decrease the risk of cardiovascular disease in diabetes or metabolic syndrome regardless of whether glycaemia worsens.

SUMMARY

One unassailable truth is that statin therapy is beneficial and should rarely, if ever, be withheld.

Serum lipoprotein(a) levels and diabetic nephropathy among Japanese patients with type 2 diabetes mellitus

AIMS

We aimed to evaluate the association between serum lipoprotein(a) [Lp(a)] levels and diabetic nephropathy among Japanese patients with type 2 diabetes mellitus.

METHODS

This study included 581 patients with type 2 diabetes mellitus. Serum Lp(a) levels were divided into four groups; the cut-off points were at the 30th, 60th, and 90th percentile values on the basis of the distribution for all subjects. Diabetic nephropathy was defined as present when the urinary albumin-creatinine ratio was ≥33.9mg/mmol creatinine and/or the estimated glomerular filtration rate was <30ml/min/1.72m(2). Adjustment was made for age, sex, body mass index, hemoglobin A1c, duration of diabetes mellitus, current drinking, current smoking, hypertension, dyslipidemia, coronary heart disease, and stroke.

RESULTS

Higher serum Lp(a) levels were significantly associated with a higher prevalence of diabetic nephropathy: the adjusted odds ratios (95% confidence intervals) for diabetic nephropathy in relation to serum Lp(a) levels of ≤6, 7-15, 16-38, and ≥39mg/dl were 1.00 (reference), 2.74 (1.08-7.00), 3.31 (1.28-8.54), and 4.80 (1.57-14.60), respectively (P for trend=0.004).

CONCLUSIONS

The results suggest that serum Lp(a) levels may be positively associated with diabetic nephropathy among Japanese patients with type 2 diabetes mellitus.

Lipoprotein(a) predicts a new onset of chronic kidney disease in people with Type 2 diabetes mellitus

AIMS

We investigated the association between lipoprotein(a) [Lp(a)] level and new-onset chronic kidney disease (CKD) in patients with Type 2 diabetes.

METHODS

We conducted a prospective cohort study from March 2003 to December 2004 with a median follow-up time of 10.1 years. Patients aged 25-75 years with Type 2 diabetes and without CKD [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m(2) ) were consecutively enrolled. The eGFR was measured at least twice every year , and new-onset CKD was defined as a decreased eGFR status of < 60 ml/min/1.73 m(2) using a Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.

RESULTS

Of the 862 patients who were enrolled, 560 (65.0%) completed the follow-up and 125 (22.3%) progressed to CKD. The mean age and duration of diabetes were 53.3 ± 9.6 and 7.5 ± 6.0 years, respectively. The baseline eGFR was 101.8 ± 11.3 ml/min/1.73 m(2) . After adjusting for multiple confounding factors, a Cox hazard regression analysis revealed that the third tertile of Lp(a) was significantly associated with the development of CKD during the observation period when compared with the first tertile [hazard ratio 2.12 (95% confidence interval 1.33-3.36); P = 0.001).

CONCLUSIONS

In this prospective, longitudinal, observational cohort study, we demonstrated that the Lp(a) level was an independent prognostic factor for the future development of CKD in patients with Type 2 diabetes.

Relation of atherogenic lipoproteins with estimated glomerular filtration rate decline: a longitudinal study

BACKGROUND

Chronic kidney disease (CKD) is associated with dyslipidemia, but the role of atherogenic lipid fractions in CKD progression remains unclear. Here we assess whether baseline plasma levels of lipoprotein(a) [Lp(a)] and apolipoprotein C-III (apoC-III), causal cardiovascular (CV) risk factors being studied as therapeutic targets, are associated with decreasing estimated glomerular filtration rate (eGFR) over time.

METHODS

In the Penn Diabetes Heart Study (PDHS), a single-center observational cohort of type 2 diabetes patients without clinical CV disease or pre-existing CKD, we performed linear mixed effects modeling with incremental multivariable analysis to evaluate the effects of baseline plasma Lp(a) and apoC-III on the slope of eGFR over time for subjects with longitudinal data (N = 400).

RESULTS

Each two-fold higher plasma Lp(a) level was associated with an additional decline in eGFR by 0.50 mL/min/year in the fully adjusted model (p < 0.001). Baseline Lp(a) levels greater than the atherogenic cut-point of 30 mg/dL were associated with a decline in eGFR by 2.75 mL/min/year compared to 1.01 mL/min/year in subjects with baseline Lp(a) less than 30 mg/dL (p < 0.001). Although each two-fold higher apoC-III level was also associated with statistically significant decline in eGFR over time, as expected the association was attenuated after adjusting for baseline triglycerides, the key lipid intermediary regulated by apoC-III in circulation.

CONCLUSIONS

Elevated baseline plasma Lp(a) levels are associated with a decrease in eGFR over time independent of race, lipid medication use, and albuminuria, whereas elevated baseline apoC-III levels are associated with eGFR decline in a triglyceride-dependent fashion.

Lipoprotein (a): gene genie

PURPOSE OF REVIEW

Despite being both the longest known and the most prevalent genetic risk marker for atherosclerotic cardiovascular disease (CVD), little progress has been made in agreeing a role for lipoprotein (a) [Lp(a)] in clinical practice and developing therapies with specific Lp(a)-lowering activity. We review barriers to progress, and discuss areas of controversy which are important to future research.

RECENT FINDINGS

Epidemiological and genetic studies have supported a causal role for Lp(a) in accelerated atherosclerosis, independent of other risk factors. Progress continues to be made in the understanding of Lp(a) metabolism, and Lp(a) levels, rather than apolipoprotein (a) isoform size, have been shown to be more closely related to CVD risk. Selective Lp(a) apheresis has offered some evidence that Lp(a)-lowering can improve cardiovascular end-points.

SUMMARY

We have acquired a great deal of knowledge about Lp(a), but this has not yet led to reductions in CVD. This is at least partially due to disagreement over Lp(a) measurement methodologies, its physiological role and the importance of the elevations seen in renal diseases, diabetes mellitus and familial hypercholesterolaemia. Renewed focus is required to bring assays into clinical practice to accompany new classes of therapeutic agents with Lp(a)-lowering effects.

Relation of serum lipids and lipoproteins with progression of CKD: The CRIC study

BACKGROUND AND OBJECTIVES

Hyperlipidemia is common in patients with CKD. The objective of this study was to evaluate whether measures of plasma lipids and lipoproteins predict progression of kidney disease in patients with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Prospective cohort study in adults (n=3939) with CKD aged 21-74 years recruited between 2003 and 2008 and followed for a median of 4.1 years. At baseline, total cholesterol, triglycerides, very-low-density lipoprotein cholesterol (VLDL-C), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), apoA-I , apoB, and lipoprotein(a) [Lp(a)] were measured. The outcomes were composite end point of ESRD or 50% decline in eGFR from baseline (rate of change of GFR).

RESULTS

Mean age of the study population was 58.2 years, and the mean GFR was 44.9 ml/min per 1.73 m(2); 48% of patients had diabetes. None of the lipid or lipoprotein measures was independently associated with risk of the composite end point or rate of change in GFR. However, there were significant (P=0.01) interactions by level of proteinuria. In participants with proteinuria<0.2 g/d, 1-SD higher LDL-C was associated with a 26% lower risk of the renal end point (hazard ratio [HR], 0.74; 95% confidence interval [95% CI], 0.59 to 0.92; P=0.01), and 1-SD higher total cholesterol was associated with a 23% lower risk of the renal end point (HR, 0.77; 95% CI, 0.62 to 0.96; P=0.02). In participants with proteinuria>0.2 g/d, neither LDL-C (HR, 0.98; 95% CI, 0.98 to 1.05) nor total cholesterol levels were associated with renal outcomes. Treatment with statins was reported in 55% of patients and was differential across lipid categories.

CONCLUSIONS

In this large cohort of patients with CKD, total cholesterol, triglycerides, VLDL-C, LDL-C, HDL-C, apoA-I, apoB, and Lp(a) were not independently associated with progression of kidney disease. There was an inverse relationship between LDL-C and total cholesterol levels and kidney disease outcomes in patients with low levels of proteinuria.

Elevated serum β2-glycoprotein-I-lipoprotein(a) complexes levels are associated with the presence and complications in type 2 diabetes mellitus

AIMS

To examine the serum levels of β2-glycoprotein I-lipoprotein(a) complexes [β2-GPI-Lp(a)] in type 2 diabetes mellitus (T2DM) patients and evaluate the association of the complexes with complications in T2DM.

METHODS

Fifty two T2DM patients (22 with complications and 30 free of complications) and 52 age/gender-matched healthy controls were studied. Serum concentrations of β2-GPI-Lp(a) and ox-Lp(a) were measured by "sandwich" ELISAs and their associations with complications were examined using multiple linear regression.

RESULTS

Mean serum β2-GPI-Lp(a) (1.19 ± 0.30 U/mL vs. 0.89 ± 0.20 U/mL, p<0.001) and ox-Lp(a) concentrations (13.34 ± 11.73 mg/L vs. 5.26 ± 3.34 mg/L, p<0.001) were both significantly higher in T2DM than in controls. The area under the ROC curve (AUC) for β2-GPI-Lp(a) and ox-Lp(a) was 0.725 and 0.738, respectively. β2-GPI-Lp(a) levels were markedly higher in patients with complications than those without complication (1.39 ± 0.28 U/mL vs. 1.04 ± 0.31 U/mL, p<0.01), whereas no marked difference was found in ox-Lp(a). In multivariate regression analysis, the association between β2-GPI-Lp(a) and complications remained significant (β=0.249, p<0.05, respectively) after adjustments were made for other traits.

CONCLUSIONS

Elevated β2-GPI-Lp(a) may reflect chronic underlying pathophysiological processes involved in development of complications of T2DM.

Effects of N-acetyl cysteine on serum lipoprotein (a) and proteinuria in type 2 diabetic patients

BACKGROUND

About 30-40% of diabetic patients who developed nephropathy have lipoprotein disorders, especially lipoprotein a [Lp(a)], which is related to atherosclerosis.

OBJECTIVES

The aim of this study was to investigate the effect of N-acetyl cysteine (NAC) on the serum levels of Lp(a) and amount of proteinuria in a group of type 2 diabetic patients with diabetic nephropathy.

PATIENTS AND METHODS

A total of 40, type 2 diabetic (T2D) patients, patients with proteinuria, were randomly divided into two groups. The experimental group was treated by NAC (1200 mg/day) for two months in conjunction with conventional treatment for diabetes and hypertension. Control group received routine medications.

RESULTS

No significant change was identified in serum Lp(a) during treatment with NAC (P >0.05). However, NAC decreased the amount of proteinuria, serum triglyceride (TG) level and systolic blood pressure in experimental group compared to the control group (P <0.05).

CONCLUSIONS

These findings suggest that treatment with NAC has no significant effect on the serum level of Lp (a). However, it has beneficial effects on the reduction of proteinuria, serum TG level and systolic blood pressure in T2D patients with nephropathy. Further prospective studies are needed to determine its full role.

Lipoprotein(a) in type 2 diabetic subjects and its relationship to diabetic microvascular complications

AIM: To estimate the level of serum lipoprotein (a) [Lp (a)] in type 2 diabetes mellitus patients and to determine the relationship between Lp(a) in type 2 diabetes mellitus patients and micro-vascular complications.

METHODS: A cross sectional study was performed that enrolled 144 subjects with type 2 diabetes mellitus above the age of 25 years attending outpatient clinic of Government Medical College, Kozhikode. Lp(a) levels were measured quantitatively in venous samples using Turbidimetric Immunoassay in all subjects. Each patient was evaluated for micro vascular complications, namely diabetic retinopathy, nephropathy and neuropathy. The relationship between Lp(a) levels and the micro vascular complications was assessed by univariate analysis.

RESULTS: Mean age of cases was 53.93 ± 10.74 years with a male to female ratio of 1.3:1. Mean duration of diabetes was 9.53 ± 7.3 years. Abnormal Lp(a) levels (≥ 30 mg/dL) were observed in 38 (26.4%) diabetic subjects. Seventy-eight (54.16%) cases had diabetic nephropathy and significantly higher Lp(a) levels were found among these cases [Median 28.2 mg/dL (Interquartile range; IQR 24.4-33.5) vs 19.3 mg/dL (IQR 14.7-23.5); P < 0.05]. Retinopathy was present among 66 (45.13%) cases and peripheral neuropathy was detected among 54 (37.5%) cases. However, Lp(a) levels were not significantly different among those with or without retinopathy and neuropathy. Positive correlation was found between higher Lp(a) levels and duration of diabetes (r = 0.165, P < 0.05) but not with HbA1c values (r = – 0.083).

CONCLUSION: Abnormal Lp(a) levels were found among 26.4% of diabetic subjects. Patients with diabetic nephropathy had higher Lp(a) levels. No association was found between Lp(a) levels and diabetic retinopathy or neuropathy. Longer duration of diabetes correlated with higher Lp(a) levels.

Validity of biomarkers predicting onset or progression of nephropathy in patients with Type 2 diabetes: a systematic review

Novel biomarkers predicting onset or progression of nephropathy in patients with Type 2 diabetes have been recently identified. We performed a systematic review to assess the validity of biomarkers predicting onset or progression of nephropathy in patients with Type 2 diabetes in longitudinal studies. The methodological quality of the studies was scored using Standards for Reporting of Diagnostic Accuracy (STARD) criteria and the independent predictive value of the biomarkers beyond conventional risk factors was scored according to the adjustment for these risk factors. Validity of the biomarkers was determined by summarizing the methodological quality and the adjustment score. We identified 15 studies describing 27 biomarkers. Six studies had sufficient methodological quality. These studies identified 13 valid and significant markers for nephropathy in diabetes: serum interleukin 18, plasma asymmetric dimethylarginine; and urinary ceruloplasmin, immunoglobulin G and transferrin were considered valid markers predicting onset of nephropathy. Plasma asymmetric dimethylarginine, vascular cell adhesion molecule 1, interleukin 6, von Willebrand factor and intercellular cell adhesion molecule 1 were considered valid biomarkers predicting progression of nephropathy. Plasma high-sensitivity C-reactive protein, E-selectin, tissue-type plasminogen activator, von Willebrand factor and triglycerides were considered valid markers predicting onset and progression of nephropathy. Several novel biomarkers for prediction of nephropathy in diabetes have been published, which can potentially be applied in clinical practice and research in future. Because of the heterogeneous quality of biomarker studies in this field, a more rigorous evaluation of these biomarkers and validation in larger trials are advocated.

Fibrinogen, Lp(a), Microalbuminuria and Left Ventricular Mass Index: Cardiovascular Disease Risk factors in Diabetes

The present work was undertaken to study interrelation of Fibrinogen, Lp(a) and LVMI in Type II diabetes patients with or without nephropathy. 100 Type II Diabetic patients attending OPD/IPD of DMC&H, Ludhiana were included. They were divided in two groups. Group I: 50 patients without microalbuminuria (MAU). Group II: 50 patients with MAU. Fibrinogen (Clauss method), Lp(a) and MAU were estimated on Multichannel Autoanalyzer Hitachi-911 (Roche). LVMI was estimated by echocardiography using formula of Devereux and Reicheck. Type II diabetes patients with MAU had significantly raised levels of Fibrinogen, Lp(a), and LVMI as compared to normoalbuminuric diabetics (P < 0.01). Group II patients had positive correlation between Lp(a) and LVMI but no relation between Fibrinogen and LVMI. MAU, marker of microangiopathy, is associated with higher Fibrinogen and Lp(a) levels. This becomes basis of increase cardiovascular risk as demonstrated by higher mean LVMI in Group II patients.

Lipoprotein a: where are we now?

PURPOSE OF REVIEW

To provide an update of the literature describing the link between lipoprotein a and vascular disease.

RECENT FINDINGS

There is evidence that elevated plasma lipoprotein a levels are associated with coronary heart disease, stroke and other manifestations of atherosclerosis. Several mechanisms may be implicated, including proinflammatory actions and impaired fibrinolysis.

SUMMARY

Lipoprotein a potentially represents a useful tool for risk stratification in the primary and secondary prevention setting. However, there are still unresolved methodological issues regarding the measurement of lipoprotein a levels. Targeting lipoprotein a in order to reduce vascular risk is hampered by the lack of well tolerated and effective pharmacological interventions. Moreover, it has not yet been established whether such a reduction will result in fewer vascular events. The risk attributed to lipoprotein a may be reduced by aggressively tackling other vascular risk factors, such as low-density lipoprotein cholesterol.

Long-term lifestyle intervention lowers the incidence of stroke in Japanese patients with type 2 diabetes: a nationwide multicentre randomised controlled trial (the Japan Diabetes Complications Study)

AIMS/HYPOTHESIS

The aim of the study was to clarify whether a therapeutic intervention focused on lifestyle modification affected the incidence of vascular complications in patients with established diabetes.

METHODS

A total of 2,033 eligible Japanese men and women aged 40-70 years with type 2 diabetes from 59 institutes were randomised to a conventional treatment group (CON), which continued to receive the usual care, and a lifestyle intervention group (INT), which received education on lifestyle modification regarding dietary habits, physical activities and adherence to treatment by telephone counselling and at each outpatient clinic visit, in addition to the usual care. Randomisation and open-label allocation were done by a central computer system. Primary analysis regarding measurements of control status and occurrence of macro- and microvascular complications was based on 1,304 participants followed for an 8 year period.

RESULTS

Although status of control of most classic cardiovascular risk factors, including body weight, glycaemia, serum lipids and BP, did not differ between groups during the study period, the incidence of stroke in the INT group (5.48/1,000 patient-years) was significantly lower than in the CON group (9.52/1,000 patient-years) by Kaplan- Meier analysis (p=0.02 by logrank test) and by multivariate Cox analysis (HR 0.62, 95% CI 0.39-0.98, p=0.04). The incidence of CHD, retinopathy and nephropathy did not differ significantly between groups. Lipoprotein(a) was another significant independent risk factor for stroke.

CONCLUSIONS/INTERPRETATION

These findings suggest that lifestyle modification had limited effects on most typical control variables, but did have a significant effect on stroke incidence in patients with established type 2 diabetes.

CLINICAL TRIAL REGISTRATION

UMIN-CTR C000000222

FUNDING

The Ministry of Health, Labour and Welfare, Japan