[A multicenter randomized controlled study of the efficacy and safety of oseltamivir in the treatment of influenza in a high risk population].

Department of Respiratory Diseases, China-Japan Friendship Hospital, Beijing 100029, China.
Zhonghua jie he he hu xi za zhi = Zhonghua jiehe he huxi zazhi = Chinese journal of tuberculosis and respiratory diseases 07/2004; 27(7):455-9.
Source: PubMed

ABSTRACT To evaluate the efficacy and safety of oseltamivir in the treatment of influenza in a high risk population.
A randomized, open, control trial was conducted from Nov. 2002 to Feb. 2003. Patients with chronic respiratory disease, such as chronic bronchitis, obstructive emphysema, bronchial asthma, bronchiectasis or chronic cardiac disease, and with symptoms of influenza were enrolled. They should satisfy the following criteria: Fever > or = 37.8 degrees C plus at least two of the following influenza symptoms: coryza/nasal congestion, sore throat, cough, myalgia/muscle aches and pain, fatigue, headache and chills/sweats. Within 48 h after the onset of the symptoms, the patients were randomly assigned to oseltamivir group (oseltamivir 75 mg, twice daily for 5 days) or control group (symptom relief medicine only).
Fifty-six of the 108 recruited patients were identified as influenza-infected through laboratory test. They were defined as intent-to-treat infected population (ITTI) (27 oseltamivir, 29 control). The duration of influenza symptom was 64 h shorter (36.7%) and AUC score of the influenza symptom was decreased by 618 (43.1%) in the oseltamivir group as compared with those in the control group. The fever duration was 46.8 h (45.0%) less in the oseltamivir group than that in the control group. It took 6 d for the oseltamivir group and 11 days for the control group to recover to the basic health status. Secondary complications such as bronchitis, sinusitis and pneumonia occurred 11% (3/27) in the oseltamivir group and 45% (13/29) in the control group. The treatment expense for influenza and its complication was 587.4 RMB in the oseltamivir group and 786.5 RMB in the control group, which showed no significant difference (P = 0.246).
It is suggested that oseltamivir is effective and well tolerated in patients with chronic respiratory or cardiac diseases. It can reduce the fever duration and severity of influenza symptom, and decrease the incidence of secondary complications and antibiotic use, while does not increase the total medical cost.

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