Factors associated with adherence to combination therapy of interferon and ribavirin for patients with chronic hepatitis C: importance of patient's motivation and physician's treatment experience.
OBJECTIVE
Adherence to combination therapy with interferon (IFN) or pegylated IFN plus ribavirin for chronic hepatitis C patients is important for a better virological response. However, the impact of the patient's treatment experience and treatment centre on adherence to combination therapy has not been fully analysed. In this prospective study, we analysed the factors that might have an effect on adherence to therapy in patients who had initial or retreatment IFN therapy.


METHODS
We consecutively enrolled 363 patients with chronic hepatitis C; 221 were IFN naïve and 142 were undergoing retreatment. The mean ages of the naïve and retreatment groups were 54.8 and 55.7 years respectively. IFN alpha-2b was administered daily for 2 weeks, followed by three times per week for 22 weeks, while ribavirin was administered daily. We evaluated the tolerability and response to combination therapy and analysed its relevant factors.


RESULTS
Of the 363 patients, 189 (52%) achieved 80% adherence. The multivariate logistic regression analysis revealed that retreatment, centre with more patients treated, patient age (<55 years), male, genotype 2 and dosage of IFN per weight (<0.13 million units/kg) were associated with achievement of 80% adherence to combination therapy. Accordingly, the achievement of 80% adherence was more frequent in the retreatment (62%) than that in the naïve group (46%) (P<0.01) and in centres with more patients treated (57%) than in those with less patients treated (46%) (P=0.03).


CONCLUSIONS
The present data suggest that the patient's motivation and the physician's treatment experience may be important for a better adherence to combination therapy for patients with chronic hepatitis C.
Tanioka
Daisuke
D
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Iwasaki
Yoshiaki
Y
Araki
Yasuyuki
Y
Osawa
Toshiya
T
Ikeda
Hiroshi
H
Ando
Masaharu
M
Kobashi
Haruhiko
H
Sakaguchi
Kohsaku
K
Shiratori
Yasushi
Y
Yamamoto
Kazuhide
K
D004359:Drug Therapy, Combination; D005260:Female; D019698:Hepatitis C, Chronic / Q000188:drug therapy*; D006801:Humans; D007372:Interferons / Q000627:therapeutic use*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009042:Motivation; D010342:Patient Acceptance of Health Care / Q000523:psychology*; D010818:Practice Patterns, Physicians'; D011446:Prospective Studies; D012254:Ribavirin / Q000627:therapeutic use*; D018709:Statistics, Nonparametric
D012254:Ribavirin; D007372:Interferons