Effects of obstructive sleep apnea severity on serum lipid levels in Greek children with snoring

Although obstructive sleep apnea (OSA) is related to dyslipidemia in adults, limited data are available regarding its effects on serum lipids during childhood. Aim of this study was to assess the potential relationships between severity of OSA and cholesterol or triglyceride levels in a cohort of Greek children. Data from children with snoring who underwent polysomnography and complete serum lipids measurements during a specified study period were analyzed retrospectively. Overall, obese children (n = 261) had lower HDL cholesterol levels than non-obese subjects (n = 113) (49.6 +/- 10.5 vs. 53.9 +/- 11.4 mg/dL; p = 0.001) and higher triglyceride concentrations (69.8 +/- 32.2 vs. 63.2 +/- 27 mg/dL; p = 0.041). Non-obese subjects with moderate-to-severe OSA did not differ in triglycerides, total, and LDL cholesterol concentrations but had lower HDL cholesterol, when compared to non-obese children with primary snoring/mild OSA (50.4 +/- 13.1 vs. 54.9 +/- 10.7 mg/dL; p = 0.008). The risk for having low HDL cholesterol (a parts per thousand currency sign40 mg/dL) was threefold higher in non-obese subjects with moderate-to-severe OSA than in those with primary snoring/mild OSA, even after adjustment for age and gender [OR = 3.44 (95% CI 1.44 to 8.24; p = 0.006)]. Concentrations of serum lipids in obese children were not associated with severity of OSA. HDL cholesterol was 48.5 +/- 8.7 mg/dL in subjects with moderate-to-severe OSA and 50.0 +/- 11.1 mg/dL in children with primary snoring/mild OSA (p = 0.519). HDL cholesterol levels are inversely related to severity of OSA in non-obese children with snoring

Effect of physical state and particle size distribution on dissolution enhancement of nimodipine/PEG solid dispersions prepared by melt mixing and solvent evaporation

The physical structure and polymorphism of nimodipine were studied by means of micro-Raman, WAXD, DSC, and SEM for cases of the pure drug and its solid dispersions in PEG 4000, prepared by both the hot-melt and solvent evaporation methods. The dissolution rates of nimodipine/PEG 4000 solid dispersions were also measured and discussed in terms of their physicochemical characteristics. Micro-Raman and WAXD revealed a significant amorphous portion of the drug in the samples prepared by the hot-melt method, and that saturation resulted in local crystallization of nimodipine forming, almost exclusively, modification I crystals (racemic compound). On the other hand, mainly modification II crystals (conglomerate) were observed in the solid dispersions prepared by the solvent evaporation method. However, in general, both drug forms may appear in the solid dispersions. SEM and HSM microscopy studies indicated that the drug particle size increased with drug content. The dissolution rates were substantially improved for nimodipine from its solid dispersions compared with the pure drug or physical mixtures. Among solid dispersions, those resulting from solvent coevaporation exhibited a little faster drug release at drug concentrations lower than 20 wt%. Drug amorphization is the main reason for this behavior. At higher drug content the dissolution rates became lower compared with the samples from melt, due to the drug crystallization in modification II, which results in higher crystallinity and increased particle size. Overall, the best results were found for low drug content, for which lower drug crystallinity and smaller particle size were observed