Interactions of lipoprotein(a) with diabetes mellitus, apolipoprotein B and cholesterol enhance the prognostic values for coronary artery disease

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.

Serum total carbohydrates, conjugated carbohydrates and total protein glycation index in diabetes mellitus

BACKGROUND

Diabetes mellitus is defined according to fasting blood glucose and clinical signs. But, the markers of glycation have been used recently as a criterion to diagnose and monitor the therapy.

OBJECTIVES

To measure serum total- and conjugated- saccharides and to define the new marker as serum total protein glycation index (sTPGI ) for diabetes.

DESIGN AND METHODS

The study population consisted of 172 subjects who were divided to control and diabetic cases. Serum total and conjugated saccharides were measured and sTPGI was defined to discriminate serum glycosylated and glycated saccharides.

RESULTS

Patients with diabetes compared with the controls had increased levels of serum (free) glucose, HbA1c, serum total carbohydrates, total conjugated carbohydrates and sTPGI. All three indices of serum carbohydrates showed significant positive correlation with serum glucose, HbA1c and diabetes. The equations: sTPGI = 0.12 Glucose (mg/dL) + 12 and sTPGI = 3.5HbA1c (%) + 5, were deduced for the association of sTPGI with serum free glucose and HbA1c. In ROC analysis, both HbA1c (AUC = 0.965, p ≤ 0.001) and sTPGI (AUC = 0.734, p ≤ 0.001) had strong and significant efficiency to discriminate diabetic cases from control subjects.

CONCLUSIONS

The results confirm that sTPGI obtained by indirect assay has high significant efficiency comparable to HbA1c to diagnose diabetes. sTPGI relative to HbA1c indicates the mean level of glycaemia over a shorter period of about one month so it responds more quickly to changes in therapy.

Relationship between lipoprotein(a) and colorectal cancer among inpatients: a retrospective study

The present study was to explore the association between lipoprotein(a) [Lp(a)] and colorectal cancer (CRC) among inpatients. This study included 2822 participants (393 cases vs. 2429 controls) between April 2015 and June 2022. Logistic regression models, smooth curve fitting, and sensitivity analyses were performed to investigate the relationship between Lp(a) and CRC. Compared with the lower Lp(a) quantile 1 (<79.6 mg/L), the adjusted odds ratios (ORs) in quantile 2 (79.6-145.0 mg/L), quantile 3 (146.0-299.0 mg/L), and quantile 4 (≥300.0 mg/L) were 1.41 (95% confidence interval [CI]: 0.95-2.09), 1.54 (95% CI: 1.04-2.27), 1.84 (95% CI: 1.25-2.7), respectively. A linear relationship between lipoprotein(a) and CRC was observed. The finding that Lp(a) has a positive association with CRC supports the "common soil" hypothesis of cardiovascular disease (CVD) and CRC.

Hypolipemic effects of histamine is due to inhibition of VLDL secretion from the liver: involvement of both H1 and H2-receptors

The research was performed to study the mechanism whereby histamine affects the profile of plasma lipids. Six groups of ten male rats were received two injections with histamine or its H1- and H2-agonists and antagonists. Histamine caused a significant decrease in the concentrations of triglyceride, total cholesterol, and LDLc, while HDLc had no significant change. The rate of VLDL secretion was 263.6 ± 25.8 mg/h dL in control rats and was inhibited by about 68% in histamine injected rats. These changes have been mimicked by either histamine H1- or H2-agonists. The effects of H1- and H2-agonists were abolished in the presence of cetirizine and famotidine respectively. Histamine causes a significant decrease in serum triglyceride, total, and LDL-cholesterol by both H1 and H2-receptors. The decrease in serum lipids is due to the inhibitory effect of histamine or its agonists on VLDL secretion from the liver.

Fixed-time and continuous assays of very-low-density lipoprotein secretion rate from rat liver: mean vs. instantaneous velocity

Aim of the study

The secretion rate of triglyceride from rat liver is assayed by the measurement of triglyceride accumulation in plasma when its clearance is inhibited. The aim of the study was to measure and compare the secretion rate of triglyceride from rat liver by two methods of fixed-time and continuous assays.

Material and methods

A single dose of 200 mg of poloxamer-407 (P-407) was injected i.p. into starved male rats. The secretion rate of triglyceride was measured by fixed-time and continuous assays.

Results

The time course for the changes of serum triglyceride following injection of P-407 showed three distinct phases: a lag period of about 30 minutes, a linear increase in serum triglyceride that lasted more than 4 hours, and a slight decline of triglyceride accumulation that lasted about 24 hours. The mean rate of triglyceride secretion was 234.1 ±9.6 mg/dl/h during the linear phase. The linear phase was divided into five time protocols of 240, 180, 120, 60, and 30 minutes and the secretion rate was measured at three points of time in each protocol. The mean rate of triglyceride secretion was 3.91 ±0.15, 3.83 ±0.16, 3.76 ±0.29, 3.57 ±0.43 and 3.13 ±0.34 mg/dl/min in these protocols respectively. In the kinetic assay, the change in the absorbance per three successive five minutes (ΔA/Δt) was measured and the secretion rate was calculated as 3.82 ±0.11 mg/dl/min.

Conclusions

The rate of triglyceride secretion can be measured by both fixed-time and kinetic assays and was about 3.82 ±0.11 mg/dl/min. The results of the two methods are more corresponded as the mean and instantaneous velocity respectively.

Iron hypothesis and coronary artery disease in geriatric patients

Context and aims: Iron is a pro-oxidant factor in the pathogenesis of CAD. The association of body iron status was investigated relative to the occurrence and severity of CAD.Design and methods: The subjects consisted of 110 males and 115 females who were classified as either a CAD case or a control according to the results of coronary angiography.Results: A new parameter, the "serum free iron index," was defined as the ratio of serum iron to UIBC. The level of ferritin showed significant increase [97.2 (67.0-171.2) µg/L vs. 85.6 (52.5-129.4), p = .034], whereas serum total iron, free iron index, transferrin, UIBC and iron saturation were unchanged in CAD patients relative to control group. Among the indices of body iron only serum ferritin had significant association with the likelihood (OR of 1.004 (1.000-1.007), p = .04) and severity of CAD [χ²(3)= 7.99, p = .01], but the correlation was lessened in the presence of classical risk factors. Serum ferritin had also the highest and significant efficiency to predict CAD (AUC = 0.61, p = .020).Conclusions: Serum ferritin as a marker of intracellular iron has significant association with CAD; nevertheless, the correlation is not independent. Since iron deficiency is prevalent in elderly patients, iron hypothesis needs to expand to the both sides of iron deficiency and toxicity.

Serum Creatinine and Occurrence and Severity of Coronary Artery Disease

Introduction:

The risk for cardiovascular disease is increased in all stages of the impairment of renal function. It is proposed that serum creatinine is a marker of diabetes and coronary artery disease (CAD) as well as the kidney function.

Aim:

to study the association of serum creatinine with the likelihood and severity of CAD. The study population consisted of 262 males and 266 females who were classified as CAD cases and controls according to the results of coronary angiography.

Results:

Patients with CAD compared with the controls had increased levels of serum urea and creatinine. Serum creatinine showed significant positive correlation with male sex, hypertension and negative correlation with total- and HDL-cholesterol and apoAI. Serum urea, uric acid and potassium were the major determinants of creatinine. All hematological parameters were strong negative correlates of creatinine. None of markers of inflammation had significant correlation with creatinine. Creatinine was associated significantly with the prevalence [odds ratio of 1.79 (1.47-2.20), p<0.001] and severity of CAD [F(3,528)= 3.0, p=0.03]. Serum creatinine was excluded from the regression equation after adjustment for major risk factors.

Conclusion:

Serum creatinine has significant association with CAD, but the correlation is not independent. Creatinine have significant association with markers of kidney function and body water status, but not with markers of inflammation and insulin function.

Esterification of HDL-cholesterol is Decreased in Diabetes Mellitus and CAD and Enhanced Following Treatment with Statins

Background:

The main goal of using statins is to reduce the level of plasma cholesterol, meanwhile they have a wide spectrum of actions.

Objectives:

To identify the effect of statins on fractional cholesterol esterification (FCE) as well as the complete profile of lipids and (apo)lipoproteins.

Design and methods:

In an age and sex matched case-control study, 400 subjects who were referred for coronary angiography were divided into two groups according using statins.

Results:

Total cholesterol was decreased significantly following treatment with statins (165.6 ± 38.0 mg/dL vs. 205.3 ± 48.4, p≤0.001). About 90% of the reduction was occurred in nonHDL and 10% in HDL fraction. Reduction of nonHDL cholesterol (125.2 ± 35.2 mg/dL vs. 162.8 ± 45.2, p≤0.001) occurred on both unesterified (52.4 ± 21.5 mg/dL vs. 65.2 ± 25.5, p≤0.001) and esterified cholesterol (74.7 ± 27.3 mg/dL vs. 96.6 ± 34.1, p≤0.001). But the decrease in HDL cholesterol (40.4 ± 10.0 mg/dL vs. 42.3 ± 9.9, p≤0.079) happened exclusively in unesterified fraction (10.9 ± 3.4 vs. 15.2 ± 5.1, p≤0.001) and was counterbalanced with a significant increase in esterified portion (29.5 ± 8.2 mg/dL vs. 27.2 ± 9.5, p≤0.020). The ratio of esterified- per total- cholesterol in HDL was 67.5 ± 8.1% in the control group and was decreased to 58.0 ± 14.9% (p≤0.01) in diabetes and CAD and increased to 73.5 ± 6.9 (p≤0.01) after using statins.

Conclusions:

The results suggest that the percent of esterified cholesterol in HDL fraction is decreased in diabetes and CAD patients and increased by using statins.

The Ratio of Unesterified/esterified Cholesterol is the Major Determinant of Atherogenicity of Lipoprotein Fractions

Background

The hypothesis is proposed that the atherogenicity of lipoporotein fractions is correlated with the content of unesterified cholesterol.

Objectives

To evaluate the role and prognostic values of unesterified and esterified cholesterol in lipoprotein fractions for coronary artery disease (CAD).

Design and methods

The study population consisted of 400 patients who were divided to CAD controls and cases according to the data of coronary angiography. Fractional cholesterol esterification (FCE) as well as the complete profile of lipids and (apo)lipoproteins were determined.

Results

Total cholesterol was increased significantly in CAD patients (196.3 ± 52.3 mg/dL vs. 185.7 ± 48.0, p≤ 0.049) and the increment occurred totally in unesterified portion (77.2 ± 28.4 mg/dL vs. 71.1 ± 24.4, p≤ 0.031). HDL cholesterol showed a significant decrease in CAD group (39.9 ± 9.5 mg/dL vs. 44.6 ± 10.5, p≤ 0.001), but the decrement occurred wholly in the esterified portion (26.2 ± 9.2 mg/dL vs. 31.1 ± 8.1, p≤ 0.001). NonHDL cholesterol was increased significantly in CAD group (156.8 ± 48.3 mg/dL vs. 140.3 ± 43.6, p≤ 0.001), and the changes occurred in both un- and esterified portions. FCE in HDL was diminished significantly in CAD patients (64.8 ± 13.9% vs. 69.3 ± 7.9, p≤ 0.01). In multivariate logistic regression analysis, unesterified cholesterol in NonHDL (UeNonHDLc) and esterified cholesterol in HDL (EsHDLc) excluded total cholesterol and HDLc respectively from the regression equation. In ROC analysis, the ratio of UeNonHDLc/EsHDLc was the strongest predictor for CAD among cholesterol subfractions.

Conclusions

The results confirm that UeNonHDLc is atherogenic and EsHDLc is antiatherogenic and are independent risk factors for CAD.

Elevated lipoprotein (a) levels are associated with the presence and severity of coronary artery disease in patients with type 2 diabetes mellitus

BACKGROUND AND AIMS

The role of lipoprotein (a) [Lp(a)] in coronary artery diseases (CAD) with special clinical background such as type 2 diabetes mellitus (T2DM) has not been fully determined. The aim of the present study was to investigate the relation of Lp(a) to type 2 diabetic patients with or without CAD.

METHODS AND RESULTS

A total of 2040 consecutive patients with T2DM who received selective coronary angiography (CAG) due to angina-like chest pain were enrolled. The patients were subsequently divided into CAD and non-CAD groups according to the results of CAG. The severity of CAD was evaluated by the Gensini Score (GS), number of stenotic vessels, and history of myocardial infarction (MI). Data showed that Lp(a) levels were higher in the CAD group than in the non-CAD group (median: 15.00 mg/dL vs. 11.88 mg/dL, P = 0.025). The results from CAD subgroup analysis indicated that the patients with MI, multiple-vessel disease and high GS had higher Lp(a) levels compared with those in their matched subgroups (P < 0.05, respectively). After adjustment for confounders, Lp(a) levels were independently related to the presence and severity of CAD (CAD:OR = 1.564; MI:OR = 1.523; high GS:OR = 1.388; multiple-vessel disease:OR = 1.455; P < 0.05, respectively).

CONCLUSION

Elevated Lp(a) levels were independently associated with the presence and severity of CAD in patients with T2DM. More studies are necessary to confirm our findings.

Novel and traditional lipid-related biomarkers and their combinations in predicting coronary severity

We investigated simultaneously traditional and novel lipid indices, alone or in combination, in predicting coronary severity assessed by Gensini score (GS) in 1605 non-lipid-lowering-drug-treated patients undergoing coronary angiography. Firstly, levels of triglycerides (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), non high density lipoprotein cholesterol (non-HDL-C), apolipoprotein (apo) B, lipoprotein (a) [Lp(a)], proprotein convertase subtilisin/kexin type 9 (PCSK9), apoC3, small dense LDL (sdLDL) and large HDL were increased, while HDL-C and apoA1 levels were decreased as GS status (all p for trend <0.05). However, gender stratification analyses showed similar associations between lipids and GS in men but not in women. Secondly, multiple logistic regression analyses indicated that the 12 indices were predictive for high GS (≥24) but not for low GS (1-23) compared with normal coronary (GS = 0) except for TG (neither) and apoB (both). Finally, we found that interactions between two indices with mutually exclusive composition were positively associated with GS status except for couples of TC + apoC3, apoB/PCSK9/apoC3 + sdLDL-C. Concordant elevations in the two showed the highest predictive values for high GS (all p for trend <0.05). Therefore, lipid biomarkers were associated with coronary severity and their adverse changes in combination emerged greater risks in men but not in women.

Life Psychosocial Stresses and Coronary Artery Disease

Background:

It is hypothesized that the impacts of life events accumulate and can trigger and promote atherosclerosis in susceptible individuals. In the current study, the correlation of total life stressors during 1 year was investigated relative to coronary artery disease (CAD).

Methods:

The study population consisted of 148 males and 152 females aged 35–76 years. The subjects were classified as CAD cases and controls according to the results of coronary angiography. The severity of CAD was scored on the basis of the number and the extent of lesions at coronary arteries. The stressful events of life were assessed using Holmes-Rahe Questionnaire and was presented as total psychological stress scores per year (TPSS).

Results:

The frequency of cigarette smoking, diabetes mellitus, and hypertension was more prevalent in CAD cases than control subjects. The levels of TPSS were increased in patients with CAD compared to the controls (160.3 ± 71.3 vs. 139.8 ± 66.5, P = 0.020). TPSS was also associated positively with the levels of uric acid, erythrocytes counts, erythrocyte sedimentation rate, aspirin consumption, and negatively with high-density lipoprotein-cholesterol and apo-AI. In logistic regression analysis, TPSS correlated with the occurrence of CAD by the odds ratio of 1.773 (1.073–2.930), P = 0.025, but the association was weakened after adjustment for classical risk factors, especially hypertension. TPSS exhibited significant association with the severity of CAD [F (3,274) = 2.6, P = 0.051].

Conclusions:

The results suggest that TPSS are associated with the occurrence and severity of CAD significantly, but the association is not independent.

Calculation of LDL-Cholesterol vs. Direct Homogenous Assay

BACKGROUND

Low-density lipoprotein cholesterol (LDLc) can be calculated or measured directly and their accordance is the subject of controversy.

OBJECTIVES

The aim of this study was to identify the independent predictors of LDLc, to formulate the best equation for calculating LDLc and to evaluate the validity of it and the published formulas, including the new method with adjustable coefficient.

METHODS

The profile of serum lipids and (apo)lipoproteins of 310 subjects was used to determine the most accurate formula for calculating serum LDLc. Serum lipids, lipoproteins and apolipoproteins were measured by enzymatic, new homogenous and immunoturbidometric methods, respectively.

RESULTS

Multiple linear regression analysis indicates that total cholesterol, apoB, HDLc and triglyceride are independent predictors of LDLc. We proposed four new formulas to calculate LDLc. As total cholesterol (TC) is the major determinant of LDLc, it can be estimated simply as 0.545 of total cholesterol. Inclusion of HDLc, triglyceride, apoB and a constant value improved the equation slightly. The equation of: LDLc (mg/dl) = 0.75 TC - 0.5 HDLc - 0.1 TG had the lowest mean and SD of difference among all the methods examined here. LDLc was also calculated by the new modified Friedewald's equation using adjustable factor from Martin's table, but it did not improve the results significantly. LDLc gap was correlated significantly and positively with triglyceride and negatively with cholesterol or its subfractions.

CONCLUSIONS

Our data suggest the simplest formula: LDLc = 0.545 TC or a more detailed: LDLc = 0.75 TC - 0.5 HDLc - 0.1 TG be used for calculating serum LDLc.

Uric Acid and Coronary Artery Disease, Two Sides of a Single Coin: A Determinant of Antioxidant System or a Factor in Metabolic Syndrome

INTRODUCTION

Uric acid has antioxidant activity and it is expected to protect against coronary artery disease (CAD). Contradictory, it is a component of metabolic syndrome and so a risk factor for CAD. The associations of plasma total antioxidant capacity (TAOC) and uric acid (UA) as well as other risk factors were investigated relative to the occurrence and severity of CAD.

MATERIALS AND METHODS

The study population consisted of 148 males and 152 females aged 35-76 years who were classified as CAD cases and controls according to the results of coronary angiography. The severity of CAD was scored on the basis of the number and the extent of lesions at coronary arteries. The concentrations of UA and TAOC were measured by using of FRAP and enzymatic uricase methods.

RESULTS

The prevalence of hypertension, cigarette smoking and diabetes mellitus was more frequent in CAD cases than controls. Patients with CAD when compared with the controls had increased levels of glucose, triglycerides, creatinine, UA, TAOC and decreased levels of HDL- cholesterol. Serum UA was high positive correlate of serum total and LDL-cholesterol, triglyceride, creatinine, BUN, bilirubin, TAOC and negative correlate of glucose and HDL-C. TAOC and its major determinant UA but not bilirubin and albumin are significantly associated with the prevalence and severity of CAD. In multivariate analysis and in the absence of hypertension, UA but not TAOC would remain and be associated with CAD by the OR of 1.57 (1.07-2.29), p=0.02. If the results adjusted for all major risk factors including hypertension, neither TAOC nor UA would remain in the regression equation.

CONCLUSION

The results suggest that TAOC and UA but not bilirubin and albumin are associated with CAD significantly. But, the correlation is not independent and is attributed to the metabolic syndrome. The measurement of UA and TAOC will not improve the prognostic power beyond the classical risk factors.

Haplotype-based association of four lymphotoxin-alpha gene polymorphisms with the risk of coronary artery disease in Han Chinese

Lymphotoxin-alpha (LTA), a pro-inflammatory cytokine, has been implicated in the pathogenesis of coronary atherosclerosis. Meanwhile, association of some single nucleotide polymorphisms (SNPs) of LTA gene with coronary artery disease (CAD) has been evaluated; however, the results are irreproducible. We therefore investigated the relationship between four SNPs of LTA gene and CAD in Han Chinese: G+10A (rs1800683, 5'-untranslated region), A+80C (rs2239704, 5'-untranslated region), T+496C (Cys13Arg, rs2229094, exon 2), and C+804A (Thr26Asn, rs1041981, exon 3). Genotyping was performed in 438 CAD patients and 330 healthy controls. Single-locus analysis showed that the genotype and allele frequencies of G+10A polymorphism exhibited marginal differences between CAD patients and controls, although no statistical significance was observed after the Bonferroni correction. Logistic regression analysis revealed that GG genotype of G+10A polymorphism was significantly associated with the risk of CAD under the dominant mode, whereas no significant association was detected between A+80C polymorphism and CAD. In contrast, individuals carrying TT or TC genotype of T+496C polymorphism showed a decreased CAD risk relative to those with CC genotype under the recessive mode. Likewise, CC genotype of C+804A polymorphism was associated with a protective effect on CAD under the dominant mode. Further, in haplotype analysis, the haplotype G-C-T-C (in order of rs1800683, rs2239704, rs2229094 and rs1041981) was significantly associated with a decreased risk of CAD after assigning the most common haplotype A-C-T-A as a reference. In conclusion, we show a protective effect of the haplotype G-C-T-C on the occurrence of CAD, suggesting the involvement of LTA in CAD pathogenesis.

Coronary artery disease and its risk factors status in iran: a review

BACKGROUND

Coronary artery disease (CAD) is a leading cause of mortality, morbidity, and disability in the world. The high prevalence and morbidity associated with CAD in Iran is one of the most pressing health problems.

METHODS

We have reviewed the status of CAD and prevalence of its traditional and novel risk factors based on the published papers in recent years that may have an impact on the rate of CAD in Iran. Evaluation of current impact of metabolic syndrome in Iran was the other aim of this review, as it contributes to pathogenesis of coronary artery disease. We reviewed all PubMed indexed related studies. Some evidences from national articles which were published by the Ministry Of Health and Medical Education Research Council Certified Medical Journals of Islamic Republic of Iran were also included.

RESULTS

The prevalence of CAD, coronary risk factors and metabolic syndrome in Iran is higher than Western countries and similar to some Middle East countries. There are limited data with regard to novel coronary risk factors in Iran.

CONCLUSION

Primary and secondary prevention of CAD including life style modifications and dietary interventions strongly recommended in Iranian population.

Lipoprotein(a) is strongly associated with coronary artery calcification in type-2 diabetic women

BACKGROUND

Lp(a), implicated in both atherogenesis and thrombosis pathways, varies significantly by demographic and metabolic factors, providing challenges for its use in Coronary Heart Disease (CHD) risk. The purpose of this study was to investigate whether type-2 diabetic subjects, relative to non-diabetics, might benefit more from Lp(a) measurement in the prediction of CHD risk, as measured by coronary artery calcium (CAC).

METHODS

We performed cross sectional analyses in two community-based studies: the Penn Diabetes Heart Study [N = 1299 with type-2 diabetes] and the Study of Inherited Risk of Coronary Atherosclerosis [N = 860 without diabetes].

RESULTS

Blacks had 2-3 fold higher Lp(a) levels than whites in diabetic and non-diabetic samples. There was significant difference by gender (interaction p<0.001), but not race, in the association of Lp(a) with CAC in type-2 diabetic subjects. In age and race adjusted analysis of diabetic women, Lp(a) was associated with CAC [Tobit regression ratio 2.76 (95% CI 1.73-4.40), p<0.001]. Adjustment for exercise, medications, Framingham risk score, metabolic syndrome, BMI, CRP and hemoglobin A1c attenuated this effect, but the association of Lp(a) with CAC remained significant [2.25, (1.34-3.79), p = 0.002]. This relationship was further maintained in women stratified by race, or by the use of HRT or lipid lowering drugs. In contrast, Lp(a) was not associated with CAC in diabetic men, nor in non-diabetic men and women.

CONCLUSIONS

Lp(a) is a strong independent predictor of CAC in type-2 diabetic women, regardless of race, but not in men. Lp(a) does not relate to CAC in men or women without type-2 diabetes.

Lipoprotein(a) level and its association with tumor stage in male patients with primary lung cancer

BACKGROUND

Recently, attention has been focused on the effect of lipoprotein(a) [Lp(a)] on tumors because of its possible role in development of tumor angiogenesis. The aim of this study was to investigate Lp(a) serum levels in patients with lung cancer and its association with the stages of disease.

METHODS

Fasting venous blood samples were collected from 418 untreated male patients with stages I-IV lung carcinoma and were analyzed for Lp(a). The results were compared with the data from 65 healthy male controls.

RESULTS

Lp(a) levels were elevated (median 157 mg/L, range 16-1497 mg/L) in patients with lung carcinoma compared to control subjects (median 110 mg/L, range 35-706 mg/L) (p=0.004). Subgroup analysis showed that patients with stages II-IV disease had significantly higher Lp(a) concentrations than did healthy controls (p-0.05). There was an independently positive correlation between tumor stage and Lp(a) levels among patients with stages I-III (r=0.162, p=0.006). However, there was a decrease in Lp(a) in stage IV compared to stage III patients (p=0.03).

CONCLUSIONS

There is a significant association between Lp(a) and the presence and stage of lung cancer. Additional investigations with a larger number of lung cancer patients are needed to confirm these findings.