[show abstract][hide abstract] ABSTRACT: Objective. To determine if non-HDL cholesterol (N-HDL) and directly measured LDL cholesterol (D-LDL) are clinically equivalent measurements. Patients and Methods. Eighty-one subjects recruited for 2 cholesterol treatment studies had at least 1 complete fasting lipid panel and D-LDL performed simultaneously; 64 had a second assessment after 4 to 6 weeks, resulting in 145 triads of C-LDL, D-LDL, and N-HDL. To directly compare N-HDL to D-LDL and C-LDL, we normalized the N-HDL by subtracting 30 from the N-HDL (N-HDLA). Results. There was significant correlation between N-HDLA, D-LDL, and C-LDL. Correlation was significantly greater between N-HDLA and C-LDL than between N-HDLA and D-LDL. A greater than 20 mg/dL difference between measures was observed more commonly between N-HDLA and D-LDL, 29%, than between C-LDL and N-HDLA, 11% (P < 0.001), and C-LDL and D-LDL, 17% (P = 0.028). Clinical discordance was most common, and concordance was least common between N-HDL and D-LDL. Conclusions. Our findings suggest that N-HDL cholesterol and D-LDL cholesterol are not clinically equivalent and frequently discordant. As N-HDL may be superior to even C-LDL for predicting events in statin-treated patients, utilizing N-HDL to guide therapy would appear to be preferable to D-LDL when C-LDL is inaccurate.
[show abstract][hide abstract] ABSTRACT: Low-density lipoprotein cholesterol (LDL-C) can either be calculated or measured directly. Clinical guidelines recommend the use of calculated LDL-C (C-LDL-C) to guide therapy because the evidence base for cholesterol management is derived almost exclusively from trials that use C-LDL-C, with direct measurement of LDL-C (D-LDL-C) being reserved for those patients who are nonfasting or with significant hypertriglyceridemia.
Our aim was to determine the clinical equivalence of directly measured-LDL-C, using a Siemens Advia Chemistry System, and fasting C-LDL-C.
Eighty-one subjects recruited for two cholesterol treatment studies had at least one C-LDL-C and D-LDL-C performed simultaneously; 64 had a repeat lipid assessment after 4 to 6 weeks of therapy, resulting in 145 pairs of C-LDL-C and D-LDL-C.
There was significant correlation between D-LDL-C and C-LDL-C (r² = 0.86). Correlation was significantly better in those with lower total cholesterol, triglycerides, and high-density lipoprotein. In 60% of subjects, the difference between D-LDL-C and C-LDL-C was more than 5 mg/dL and greater than 6%. Clinical concordance between D-LDL-C and C-LDL-C was present in 40% of patients, whereas clinical discordance was noted in 25%. One-third had greater than a 15 mg/dL difference between D-LDL-C and C-LDL-C, whereas 25% had a greater than 20 mg/dL difference. In 47% of subjects, the difference between D-LDL-C and C-LDL-C at baseline and follow-up changed by a minimum of 10% or 10 mg/dL.
Our findings suggest that D-LDL-C is not clinically equivalent to C-LDL-C. This puts into question the current recommendation of using D-LDL-C in situations in which C-LDL-C would be inaccurate.
Journal of Clinical Lipidology 01/2010; 4(4):259-64. · 2.74 Impact Factor
[show abstract][hide abstract] ABSTRACT: Although during its initial development, lower doses of ezetimibe reduced low-density lipoprotein (LDL) significantly, ezetimibe is available only in 10-mg form. Compliant patients receiving ezetimibe 10 mg were randomized in a blinded fashion to continue therapy with ezetimibe 10 mg or to convert to a split-tablet 5-mg dose. Lipid panels were collected at baseline and after 4 weeks of therapy. The impact of the 2 ezetimibe dosing strategies on LDL and the achievement of the Adult Treatment Panel III LDL goal was evaluated. One hundred thirty patients receiving ezetimibe 10 mg were screened for eligibility. Thirty-nine of the 130 patients were randomized; 36 patients successfully completed the study. All patients who had achieved their Adult Treatment Panel III LDL goals at baseline remained at their LDL goals after conversion to 5 mg. In conclusion, conversion to the lower dose of ezetimibe did not result in any clinically meaningful or statistically significant changes in any lipid parameter.
The American journal of cardiology 07/2009; 103(11):1568-71. · 3.58 Impact Factor
[show abstract][hide abstract] ABSTRACT: To compare the clinical efficacy of ezetimibe 5 mg (prescribed as a 10-mg tablet split in half) with a whole 10-mg tablet.
From January 2003 through July 2005, all Bronx Veterans Administration ezetimibe prescriptions were for 10 mg. In August 2005, it was mandated that all new ezetimibe prescriptions be 5 mg, prescribed as a 10-mg tablet split in half.
The impact of the 2 ezetimibe dosing strategies on percent lowering of low-density lipoprotein cholesterol (LDL-C) and achievement of National Cholesterol Education Program Adult Treatment Panel III (ATP III) goals was assessed in all patients prescribed ezetimibe 5 or 10 mg.
A total of 272 patients were prescribed ezetimibe; 86 received 5 mg and 186 received 10 mg. Of those 272 patients, 197 had evaluable baseline and posttreatment LDL-C (55 taking the 5-mg dose and 142 taking the 10-mg dose). The effects of ezetimibe 5 and 10 mg on all lipid parameters were similar. Ezetimibe 10 mg reduced LDL-C by 26.1%, whereas 5 mg reduced LDL-C by 25.8%. The percentages of patients achieving goal LDL-C were similar: 61.8% (5 mg) and 60.5% (10 mg).
These data strongly suggest that ezetimibe 5 mg and ezetimibe 10 mg are clinically equivalent with respect to LDL-C reduction and achievement of ATP III LDL-C goals. Widespread adoption of this low-dose strategy could result in a potential cost savings of more than a billion dollars annually, with a potential reduction in hepatotoxicity.
The American journal of managed care 11/2008; 14(10):637-41. · 2.12 Impact Factor
[show abstract][hide abstract] ABSTRACT: Borderline increase of troponin I (cTnI) is associated with higher rates of cardiovascular events compared with normal levels in the setting of acute coronary syndrome (ACS), but the significance of borderline cTnI levels in patients without chest pain may differ. The aim of this study was to determine the prognostic implications of intermediate serum cTnI levels in patients without ACS in the intensive care unit (ICU). This was a 12-month retrospective study of 240 patients without ACS in the ICU with normal (<0.1 ng/ml) or intermediate (0.1 to 1.49 ng/ml) cTnI levels. End points included in-hospital mortality, lengths of ICU and hospital stays, and rates of postdischarge readmission and mortality. Overall in-hospital mortality was 13%, with 5% in the normal cTnI group and 28% in the intermediate cTnI group. By multivariate analysis, intermediate cTnI was independently associated with in-hospital mortality (p = 0.004) and length of ICU stay (p = 0.028). The only other independent risk factor for inpatient mortality was a standardized ICU prognostic measurement (Simplified Acute Physiology Score II score). Intermediate cTnI had no prognostic implications regarding length of hospital stay, readmission rate, or postdischarge mortality at 6 months. In conclusion, an intermediate level of cTnI in patients without ACS in the ICU is an independent prognostic marker predicting in-hospital mortality and length of ICU stay. Patients with intermediate cTnI levels who survive to discharge have equivalent out-of-hospital courses for up to 6 months compared with patients with normal cTnI levels.
The American Journal of Cardiology 10/2008; 102(5):509-12. · 3.21 Impact Factor