The Association Between Small Dense Low Density Lipoprotein and Coronary Artery Disease in North Indian Patients

Pathogenesis of coronary artery disease (CAD) is multi-factorial and several conventional risk factors have been ascribed; LDL-C being one of the important risk factor. However Indian population studies with established CAD often show LDL levels within normal range in patients with proven CAD. We hypothesized that Small dense low density lipoprotein (sdLDL) being more atherogenic might correlate more strongly to the occurrence and severity of CAD. The aim of the study was to evaluate the association between serum small dense LDL level and angiographically documented coronary artery disease. This is a cross sectional case control study in which sdLDL were measured in 126 patients with CAD and in 64 patients without CAD. Total cholesterol, HDL Cholesterol, LDL cholesterol and triglycerides were measured by standard methods along with other traditional risk factors. Direct quantitative measurement of sdLDL was done by enzymatic analysis. Mean sdLDL level was higher in patients with coronary stenosis than patients without coronary stenosis (16.3 ± 6.8 vs. 10.1 ± 5.7 mg/dL respectively, (p < 0.001). There was significant correlation between mean sdLDL and severity of CAD as assessed by syntax score with mean sdLDL level in low, intermediate and high syntax score being 15.0 ± 5.8, 20.1 ± 6.7 and 22.7 ± 7.3 mg/dL respectively (p value <0.001). A cut off value of 10.02 mg/dL was associated with presence of CAD (95 % CI 0.82-0.93, p < 0.001) using ROC curve. In conclusion Indian patients with established CAD have higher sdLDL levels compared to individuals without CAD despite having comparable LDL levels.

Ipragliflozin lowers small, dense low-density lipoprotein cholesterol levels in Japanese patients with type 2 diabetes mellitus

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Small dense LDL-C (sd LDL-C) convey cardiovascular risk in type 2 diabetes (T2D).

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Ipragliflozin reduced sd LDL-C levels in Japanese patients with T2D.

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Changes in body weight, TG and LDL-C levels contributed to sd LDL-C reduction.

Aims

This preliminary randomized, parallel-group comparative study evaluated the efficacy of ipragliflozin for reduction of small dense low-density lipoprotein cholesterol (sd LDL-C) levels in Japanese patients with type 2 diabetes mellitus (T2DM).

Methods

Sixty-two patients with T2DM (age, 56 ± 8 years; hemoglobin A1c levels, 8.1 ± 0.9%; BMI, 27.5 ± 3.3 kg/m²) were randomly assigned in a 2:1 ratio to receive ipragliflozin (50 mg/day) (treatment group; n = 40) or continued treatment (control group; n = 22) for 12 weeks.

The primary endpoints were changes in sd LDL-C levels detected using the LipoPhor AS^® system; the secondary endpoints included changes in the sd LDL-C/large buoyant LDL-C (lb LDL-C) ratio, a surrogate marker for LDL particle size, and percent changes in routine lipid parameters.

Results

The treatment group exhibited a statistically significant reduction from baseline for LDL-C levels (−0.37 mg/dL vs. 14.4 mg/dL, p = 0.038), sd LDL-C levels (−1.28 mg/dL vs. 2.81 mg/dL, p = 0.012), and sd LDL-C/lb LDL-C ratio (−3.20% vs. 4.58%, p = 0.040) compared with the control group. Multiple regression analysis among all subjects revealed change in TG levels (p = 0.011) and LDL-C levels (p = 0.024) as well as change in body weight (p = 0.006) as independent factors contributing to the reduction in sd LDL-C.

Conclusions

Ipragliflozin may have a potential for lowering sd LDL-C levels associated with increasing LDL particle size in Japanese patients with T2DM.

Switching from atorvastatin to rosuvastatin lowers small, dense low-density lipoprotein cholesterol levels in Japanese hypercholesterolemic patients with type 2 diabetes mellitus

AIMS

This open-label, randomized, parallel-group comparative study compared the efficacy of rosuvastatin (5mg/day) and atorvastatin (10mg/day) for reduction of small dense low-density lipoprotein cholesterol (sd LDL-C) levels in Japanese patients with type 2 diabetes mellitus (T2DM).

METHODS

Patients with T2DM and hypercholesterolemia with detectable sd LDL-C after receiving 10mg/day atorvastatin for ≥ 24 weeks were randomly assigned to receive rosuvastatin (5mg/day; switched treatment) or atorvastatin (10mg/day; continued treatment) for 12 weeks. The primary endpoints were changes in sd LDL-C levels and sd LDL-C/total LDL-C ratio evaluated using the LipoPhor AS(®) system.

RESULTS

There were no significant percent changes from baseline for LDL-C levels between the switched (n=55) and the continued treatment group (n=56). However, the former group exhibited a statistically significant reduction from baseline of sd LDL-C levels, sd LDL-C/total LDL-C ratio compared with the latter group (-3.8 mg/dL vs. -1.4 mg/dL, p=0.014; -2.3% vs. -0.6%, p=0.004, respectively). Multiple regression analysis among all subjects revealed that independent factors contributing to the reduction in sd LDL-C levels were a change in LDL-C (p=0.003) and triglyceride (TG) levels (p=0.006), treatment group (the switched group=1, the continued group=0; standard coefficient=-1.2, p=0.034) and baseline glycated hemoglobin A1c (HbA1c) (p=0.045), respectively.

CONCLUSION

Switching from 10mg atorvastatin to 5mg rosuvastatin may be a useful therapeutic option to reduce sd LDL-C levels in Japanese hypercholesterolemic patients with T2DM.

Lipid-lowering efficacy of rosuvastatin

BACKGROUND

Rosuvastatin is one of the most potent statins and is currently widely prescribed. It is therefore important to know the dose-related magnitude of effect of rosuvastatin on blood lipids.

OBJECTIVES

Primary objective To quantify the effects of various doses of rosuvastatin on serum total cholesterol, low-density lipoprotein (LDL)-cholesterol, high-density lipoprotein (HDL)-cholesterol, non-HDL-cholesterol and triglycerides in participants with and without evidence of cardiovascular disease. Secondary objectives To quantify the variability of the effect of various doses of rosuvastatin.To quantify withdrawals due to adverse effects (WDAEs) in the randomized placebo-controlled trials.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) Issue 10 of 12, 2014 in The Cochrane Library, MEDLINE (1946 to October week 5 2014), EMBASE (1980 to 2014 week 44), Web of Science Core Collection (1970 to 5 November 2014) and BIOSIS Citation Index (1969 to 31 October 2014). No language restrictions were applied.

SELECTION CRITERIA

Randomized controlled and uncontrolled before-and-after trials evaluating the dose response of different fixed doses of rosuvastatin on blood lipids over a duration of three to 12 weeks.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included and extracted data. WDAEs information was collected from the placebo-controlled trials.

MAIN RESULTS

One-hundred and eight trials (18 placebo-controlled and 90 before-and-after) evaluated the dose-related efficacy of rosuvastatin in 19,596 participants. Rosuvastatin 10 to 40 mg/day caused LDL-cholesterol decreases of 46% to 55%, when all the trials were combined using the generic inverse variance method. The quality of evidence for these effects is high. Log dose-response data over doses of 1 to 80 mg, revealed strong linear dose-related effects on blood total cholesterol, LDL-cholesterol and non-HDL-cholesterol. When compared to atorvastatin, rosuvastatin was about three-fold more potent at reducing LDL-cholesterol. There was no dose-related effect of rosuvastatin on blood HDL-cholesterol, but overall, rosuvastatin increased HDL by 7%. There is a high risk of bias for the trials in this review, which would affect WDAEs, but unlikely to affect the lipid measurements. WDAEs were not statistically different between rosuvastatin and placebo in 10 of 18 of these short-term trials (risk ratio 0.84; 95% confidence interval 0.48 to 1.47).

AUTHORS' CONCLUSIONS

The total blood total cholesterol, LDL-cholesterol and non-HDL-cholesterol-lowering effect of rosuvastatin was linearly dependent on dose. Rosuvastatin log dose-response data were linear over the commonly prescribed dose range. Based on an informal comparison with atorvastatin, this represents a three-fold greater potency. This review did not provide a good estimate of the incidence of harms associated with rosuvastatin because of the short duration of the trials and the lack of reporting of adverse effects in 44% of the placebo-controlled trials.