Statistical analysis: Data were expressed as mean values and standard errors or deviations. Unpaired Student's t test was used to compare groups at baseline and chi-square to assess differences between qualitative data. One-way ANOVA for repeated measures was used to evaluate the effect of drugs over time and to compare data between groups of subjects according to the type of therapy. Pairwise contrasts were made by comparing least-square mean estimates, and P values adjusted for multiple comparisons using the Bonferroni Holm method. The level of significance was set at P < 0.05. Correlation between variables was tested by the Pearson coefficient, also employed to assess whether changes in variables over time were correlated. Data analysis was performed using Statistical Analysis System software, version 8.2 (SAS Institute, Cary, NC).