Effects of long-term use of tenofovir on kidney and skeletal muscle related laboratory parameters in patients with chronic hepatitis B

Abstract

Objective Effects of long-term use of tenofovir on kidney and skeletal muscle related laboratory indexes in patients with chronic hepatitis B. Methods The medical record data of patients with chronic hepatitis B in Beijing Ditan Hospital, Capital Medical University from January 1, 2014 to December 31, 2014 were collected and retrospectively analyzed. All patients were given tenofovir 300 mg once daily and lasted for 24 months. The levels of serum creatinine, phosphorus, alkaline phosphates (ALP) and creatine kinase (CK) were tested before medication and 3, 6, 9, 12, 15, 18, and 24 months after medication. The laboratory tests suggestive of adverse events included the following: values of serum creatinine exceeding the baseline value by 44.2 μmol/L, blood phosphorus 2 times more than the upper limit of normal (ULN) and, serum CK>3 times more than ULN or CK>500 U/L for 2 consecutive times (every 3 months). Results A total of 40 patients were enrolled in this study, including 31 males and 9 females, with a mean age of 34±11 years (19-59 years). After medication, the serum creatinine levels of all patients gradually increased, but only the trend of male patients was statistically significant (P=0.03). There was no statistically significant difference in serum phosphorus and CK levels between male and female patients before and after medication (P>0.05). Of the 40 patients, 1(2.5%) case was identified as a laboratory adverse event since serum phosphorus <0.80 mmol/L for 3 consecutive times. No other laboratory test results suggesting adverse events were found. Conclusions Chronic hepatitis B patients taking tenofovir for two consecutive years might cause increase of serum creatinine and decrease of blood phosphorus, therefore monitoring should be strengthened. The medication had no significant impact on serum CK levels. Key words: Tenofovir; Hepatitis B, chronic; Antiviral agents; Safety