Kim HI et al. were used to assess treatment response. Early virologic response (EVR) was defined as a ≥ 2 log10 reduction or complete absence of serum HCV RNA after 12 weeks of treatment versus baseline. End of treatment response (ETR) was defined as a single undetectable serum HCV RNA measurement by qualitative PCR at treatment com- pletion. SVR was defined as a single undetectable serum HCV RNA measurement by qualitative PCR after 24 weeks of follow-up. Biochemical response (BR) was defined as serum ALT normalization after 24 weeks of follow-up. Re- lapse was defined as the reappearance of HCV RNA in the serum after treatment had been discontinued and ETR was documented. Drug discontinuation, dose modifica- tion, adverse events, and laboratory abnormalities were evaluated. Treatment was discontinued if adverse events were intolerable or if laboratory findings such as severe neutropenia (< 500/mm3) or anemia (hemoglobin < 6 g/dL) were abnormal in two consecutive samples. Dose modifications of PEG-IFN-α or ribavirin were implement- ed if neutropenia (< 750/mm3), anemia (hemoglobin < 10 g/dL), or thrombocytopenia (< 50 000/mm3) occurred; scheduled doses were re-administered after recovery. In addition, we assessed all of the visit records for the pres- ence of adverse events such as flu-like symptoms (fever, headache, and myalgia), fatigue, anorexia/nausea, itch- ing, rash, insomnia, alopecia, depression, or diarrhea. 3.4. Statistical Analysis Results are reported as mean ± standard deviation (SD). Continuous variables were compared using the 2-tailed Student’s t-test and categorical data using the χ2 test or Fisher’s exact test. Factors associated with SVR were ana- lyzed by univariate and multivariate analyses using a lo- gistic regression model. P values < 0.05 were considered to be statistically significant. Data were transferred into Table 1. Baseline and Demographic Characteristics of Study Patients PEG-IFN-α Plus Ribavirin in Elderly Chronic Hepatitis C a Microsoft EXCEL database (Microsoft Excel 2003) and analyzed using SPSS for Windows (version 15.0; SPSS Inc., Chicago, IL). 4. Results 4.1. Patient Baseline Characteristics Among a total of 181 treatment-naïve CHC patients (60 patients with genotype 1, 121 patients with genotype 2 or 3), 38 were aged ≥ 65 years (elderly group) and 143 were aged < 65 years (non-elderly group). Among the 181 pa- tients, 21 (8 elderly group; 13 non-elderly group) discon- tinued PEG-IFN-α plus ribavirin combination therapy due to adverse events or other reasons. The two groups were comparable with respect to the following demographic and baseline laboratory features; sex, presence of cirrho- sis, baseline serum aspartate aminotransferase (AST) or ALT levels, AST: platelet ratio index (APRI) score, baseline serum HCV RNA level, and proportion of HCV genotypes (Table 1). Nine (23.7%) patients in the elderly group and 24 (16.8%) patients in the non-elderly group had compen- sated cirrhosis. Baseline serum HCV RNA levels were 5.6 ± 0.8 log10 IU/mL in the elderly group and 5.6 ± 0.8 log10 IU/ mL in the non-elderly group. Of the 38 elderly patients, 13 (34.2 %) had HCV genotype 1 and 25 (65.8 %) had HCV 2 or 3 genotypes. Similarly, of the 143 non-elderly patients, 47 (32.9 %) had HCV genotype 1 and 96 (67.1 %) had HCV 2 or 3 genotypes. However, the elderly group had higher total bilirubin and lower albumin levels compared to the non- elderly group (0.8 ± 0.4 vs. 0.7 ± 0.3 mg/dL and 4.1 ± 0.4 vs. 4.2 ± 0.4 g/dL; P = 0.04 and 0.03, respectively). 4.2. Treatment Responses The overall treatment response and relapse rates are shown in Figure 1. The EVR, ETR, SVR, BR, and relapse rates Elderly (n = 38) Non-Elderly (n = 143) P value Age, y, mean ± SD Female, No. (%) Body mass index, mean ± SD Cirrhosis, NO. (%) Platelet count (× 103/mm3), mean ± SD AST a, IU/L, mean ± SD ALTa, IU/L, mean ± SD Total bilirubin, mg/dL, mean ± SD Albumin, g/dL, mean ± SD APRI a score, mean ± SD HCV genotype, No. (%) Type 1 Type 2 or 3 Serum HCV a RNA level, Log10 IU/mL, mean ± SD 5.6 ± 0.8 68.8 ± 4.4 14 (36.8) 22.7 ± 2.9 9 (23.7) 153.8 ± 53.9 66.1 ± 37.5 71.9 ± 58.1 0.8 ± 0.4 4.1 ± 0.4 1.2 ± 0.8 13 (34.2) 25 (65.8) 49.5 ± 11.2 67 (46.9) 23.7 ± 3.4 24 (16.8) 167.1 ± 57.7 73.0 ± 53.4 80.1 ± 68.9 0.7 ± 0.3 4.2 ± 0.4 1.3 ± 1.2 5.6 ± 0.9 47 (32.9) 96 (67.1) 0.00 0.36 0.11 0.35 0.19 0.36 0.46 0.04 0.03 0.51 0.91 1.00 a Abbreviations: ALT, Alanine Aminotransferase; APRI, platelet ratio index; AST, Aspartate Aminotransferase; HCV, hepatitis C virus 432 Hepat Mon. 2012