Advances in Clinical and Experimental Medicine

Title abbreviation: Adv Clin Exp Med
JCR Impact Factor (IF) – 2.1
5-Year Impact Factor – 2.2
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Index Copernicus  – 161.11; MEiN – 140 pts

ISSN 1899–5276 (print)
ISSN 2451-2680 (online)
Periodicity – monthly

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Advances in Clinical and Experimental Medicine

2017, vol. 26, nr 2, March-April, p. 333–338

doi: 10.17219/acem/61609

Publication type: original article

Language: English

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L-carnitine treatment of insulin resistance: A systematic review and meta-analysis

Ying Xu1,B,D, Wenjie Jiang2,C,D, Guochang Chen1,E, Wenjiao Zhu3,B, Weiliang Ding3,E, Zhijun Ge4,A, Yongfei Tan5,A, Tieliang Ma3,E,F, Guoxing Cui1,A,F

1 Department of Gastroenterology, the Affiliated Yixing Hospital of Jiangsu University, Yixing, Jiangsu, China

2 Department of Anesthesiology, the Affiliated Yixing Hospital of Jiangsu University, Yixing, Jiangsu, China

3 Central Laboratory, the Affiliated Yixing Hospital of Jiangsu University, Yixing, Jiangsu, China

4 Department of Critical Care Medicine, the Affiliated Yixing Hospital of Jiangsu University, Yixing, Jiangsu, China

5 Department of Cardiac & Thoracic Surgery, the Affiliated Yixing Hospital of Jiangsu University, Yixing, Jiangsu, China


Background. L-carnitine has been used for several years as an adjuvant therapy in oxidative stress, blood sugar, high-sensitivity C-reactive protein (CRP), anemia, etc. However, the efficacy of L-carnitine treating insulin resistance (IR) remains controversial. Homeostasis model assessment of Insulin Resistance (HOMA-IR) is widely used in the clinical evaluation of patients with IR.
Objectives. A meta-analysis, including randomized controlled trials (RCTs), was performed to assess the effect of L-carnitine on HOMA-IR patients.
Material and Methods. The Cochrane Library, PubMed, and EMBASE databases were systematically searched to identify RCTs which evaluated the effects of L-carnitine on HOMA-IR patients. We screened relevant studies according to predefined inclusion and exclusion criteria. In the selected articles, we extracted the data: study design, sample size, age, L-carnitine dose and regimen, body mass index (BMI) of patients, mode of administration, study duration and study outcomes.
Results. A total of 5 studies were included for the meta-analysis. The result showed L-carnitine was useful in the treatment of IR (WMD –0.724, CI –0.959 –0.488, p < 0.0001). Evaluation at 3, 6, 9, 12 months, the p-values were 0.875, 0.165, 0.031, 0, 007, respectively.
Conclusion. L-carnitine was useful in treating patients with IR. L-carnitine can treat IR more effectively with prolonging the medication time. However, more RCTs with long-term L-carnitine treatment of IR are needed to confirm the viewpoint.

Key words

insulin resistance, meta-analysis, L-carnitine

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