Aloia JF, Li-Ng M, Pollack S. not have a significant impact on serum levels of Vitamin D. 0.05 was reflected significant. The primary end-point was the change in serum fasting lipid profile and Vitamin D after treatment for 4 weeks. The secondary endpoints were changes in fasting blood glucose and high sensitive C-reactive protein (hsCRP). RESULTS From 102 patients, who came into the trial, 25 (24.5%) dropped out; hence, Tiagabine hydrochloride the final sample size was 77 (78.2%). Noncompliance with the study protocol (= 21), drug intolerance (= 2), and relocation (= 2) were the reasons for the drop-out. We failed to find any significant difference ( 0.05) when we compared the baseline data of biochemical and anthropometric factors before the first treatment period with those before the second treatment period. Moreover, no significant Tiagabine hydrochloride difference was found for age, sex, presence of hyperlipidemia, BMI, presence of hypertension, presence of diabetes, and smoking status between the two groups [Table 1]. Table 1 Comparison of baseline characteristics of subjects Open in a separate window Effects of simvastatin versus placebo on Vitamin D Statin therapy did not have a significant effect on serum levels of Vitamin D in either the statin-placebo or the placebo-statin group [= 0.90, Table 2]. Bivariate correlations were assessed between baseline values of Vitamin D and other evaluated biochemical parameters (total cholesterol, LDL-C, high-density lipoprotein cholesterol [HDL-C], triglycerides [TGs], FBG, and hs-CRP), as well as between changes in Vitamin D and other parameters during each study period. No significant correlation was found between baseline values of Vitamin D and evaluated biochemical parameters ( 0.05) [Table 3]. Furthermore, significant correlations were observed between serum Vitamin D and the following parameters: FBG (statin-placebo group, second period; 0.01), TGs (placebo-statin group, second period; 0.05 and statin-placebo first period; 0.01), LDL-C (placebo-statin group, first period; 0.05), and HDL-C (statin-placebo group, first period; 0.05) [Table 4]. Table 2 Effect of simvastatin versus placebo on Vitamin D status Open in a separate window Table 3 Correlation between baseline biochemical parameters and Vitamin D in placebo-statin group and statin-placebo group Open in a separate window Table 4 Correlation between changes in biochemical parameters in two periods of placebo-statin group and statin-placebo Open in a separate window DISCUSSION The aim of this study was to investigate the impact of simvastatin therapy on serum Vitamin D levels in dyslipidemic patients. Our results showed that simvastatin therapy for 4 weeks (40 mg/day) does not alter serum Vitamin D levels. Previous investigations around the impact of statin therapy on circulating Vitamin D levels have been inconsistent. While atorvastatin[21] and rosuvastatin[22,23] have been shown to raise 25(OH) Vitamin D levels, you will find reports Rabbit Polyclonal to LFNG with reverse findings showing that HMG-CoA reductase inhibitors do not impact serum Vitamin D concentrations.[23] It is not well known how statins might impact Vitamin D concentration, and numerous potential mechanisms have been put forward.[24] The first and by far the most plausible mechanism regards to the common metabolic fate of statins and Vitamin D. Both 25(OH) Vitamin D, and statins are metabolized in the liver by CYP3A4.[24] Therefore, the occupation of the active site of this enzyme by statins may account for the elevated 25(OH) Vitamin D levels reported in some trials. Ertugrul em et al /em . indicated that rosuvastatin (40 mg/day) as monotherapy and rosuvastatin (10 mg/day) plus fenofibrate (200 mg/day) or omega-3 fatty acids (2 g/day) cause substantial elevations in the 25(OH) Vitamin D levels (53%, 64%, and 61%, respectively).[25] Moreover, in study by Thabit em et al /em ., they found that simvastatin and atorvastatin, at any dose for duration of more than 1 year, have no additive effect on 25(OH)D level.[26] Unlike rosuvastatin and atorvastatin, no considerable change in Vitamin D concentration has been reported in patients that used fluvastatin.[23] A.2004;4:385C93. therapy did not significantly affect serum level of high-density lipoprotein cholesterol and Vitamin D level ( 0.05). Conclusions: Short-term treatment with simvastatin (40 mg/day) does not have a significant affect on serum levels of Vitamin D. 0.05 was reflected significant. The primary end-point was the change in serum fasting lipid profile and Vitamin D after treatment for 4 weeks. The secondary Tiagabine hydrochloride endpoints were changes in fasting blood glucose and high sensitive C-reactive protein (hsCRP). RESULTS From 102 patients, who came into the trial, 25 (24.5%) dropped out; hence, the final sample size was 77 (78.2%). Noncompliance with the study protocol (= 21), drug intolerance (= 2), and relocation (= 2) were the reasons for the drop-out. We failed to find any significant difference ( 0.05) when we compared the baseline data of biochemical and anthropometric factors before the first treatment period with those before the second treatment period. Moreover, no significant difference was found for age, sex, presence of hyperlipidemia, BMI, presence of hypertension, presence of diabetes, and smoking status between the two groups [Table 1]. Table 1 Tiagabine hydrochloride Comparison of baseline characteristics of subjects Open in a separate window Effects of simvastatin versus placebo on Vitamin D Statin therapy did not have a significant effect on serum levels of Vitamin D in either the statin-placebo or the placebo-statin group [= 0.90, Table 2]. Bivariate correlations were assessed between baseline values of Vitamin D and other evaluated biochemical parameters (total cholesterol, LDL-C, high-density lipoprotein cholesterol [HDL-C], triglycerides [TGs], FBG, and hs-CRP), as well as between changes in Vitamin D and other parameters during each study period. No significant correlation was found between baseline values of Vitamin D and evaluated biochemical parameters ( 0.05) [Table 3]. Furthermore, significant correlations were observed between serum Vitamin D and the following parameters: FBG (statin-placebo group, second period; 0.01), TGs (placebo-statin group, second period; 0.05 and statin-placebo first period; 0.01), LDL-C (placebo-statin group, first period; 0.05), and HDL-C (statin-placebo group, first period; 0.05) [Table 4]. Table 2 Effect of simvastatin versus placebo on Vitamin D status Open in a separate window Table 3 Correlation between baseline biochemical parameters and Vitamin D in placebo-statin group and statin-placebo group Open in a separate window Table 4 Correlation between changes in biochemical parameters in two periods of placebo-statin group and statin-placebo Open in a separate window DISCUSSION The aim of this study was to investigate the impact of simvastatin therapy on serum Vitamin D levels in dyslipidemic patients. Our results showed that simvastatin therapy for 4 weeks (40 mg/day) does not alter serum Vitamin D levels. Previous investigations on the impact of statin therapy on circulating Vitamin D levels have been inconsistent. While atorvastatin[21] and Tiagabine hydrochloride rosuvastatin[22,23] have been shown to raise 25(OH) Vitamin D levels, there are reports with opposite findings showing that HMG-CoA reductase inhibitors do not affect serum Vitamin D concentrations.[23] It is not well known how statins might affect Vitamin D concentration, and numerous potential mechanisms have been put forward.[24] The first and by far the most plausible mechanism regards to the common metabolic fate of statins and Vitamin D. Both 25(OH) Vitamin D, and statins are metabolized in the liver by CYP3A4.[24] Therefore, the occupation of the active site of this enzyme by statins may account for the elevated 25(OH) Vitamin D levels reported in some trials. Ertugrul em et al /em . indicated that rosuvastatin (40 mg/day) as monotherapy and rosuvastatin (10 mg/day) plus fenofibrate (200 mg/day) or omega-3 fatty acids (2 g/day) cause substantial elevations in the 25(OH) Vitamin D levels (53%, 64%, and 61%, respectively).[25] Moreover, in study by Thabit em et al /em ., they found that simvastatin and atorvastatin, at any dose for duration of more than 1 year, have no additive effect on 25(OH)D level.[26] Unlike rosuvastatin and atorvastatin, no considerable change in Vitamin D concentration has been reported in patients that used fluvastatin.[23] A new randomized controlled trial could not prove an effect of 12 months simvastatin therapy (40 mg/day) on Vitamin D concentration.[27] The physicochemical characteristics of different statins may also play a role in their differential effects on Vitamin D metabolism.[22,23] The present.