Background and objectives: Hypothyroid patients often complain of fatigue even after effective treatment. Thyroid hormone plays an important role in carnitine-dependent long chain fatty acid transport for oxidation and ultimate formation of ATP. Deficiency of L-carnitine has been presumed to disrupt ATP formation leading to fatigue. Present study was designed to assess the role of L-carnitine as a supplement to manage the fatigue state of hypothyroid patients.

Methods: Hypothyroid patients receiving levothyroxine (L-T₄) and suffering from fatigue symptoms were enrolled. Patients were randomly divided into Group A (Control group, n=35) and Group B (Experimental group, n=36). Patients of Group A were treated with L-T₄ only and Group B patients received L-carnitine 2 g/day in addition to L-T₄ therapy for 8 weeks. Fatigue was assessed by fatigue severity scale (FSS), physical fatigue (PF) and mental fatigue (MF) scores. Data regarding fatigue status, serum thyroid stimulating hormone (TSH) and free thyroxine (FT₄) were collected at the beginning and after 8 weeks of intervention.

Result: The mean age of Group A and Group B patients was 33.5±8.1 and 35.4±7.5 years respectively (p>0.05); and the mean body weight was 61.5±9.6 kg and 62.5±8.2 kg respectively (p>0.05). The mean baseline values of different fatigue scores and the serum TSH and FT₄ levels of patients of two groups were identical and not significantly different (p>0.05). In Group-A patients, the mean MF score improved significantly (5.2±1.5 vs 4.6±1.4; p=0.01) from baseline score after 8 weeks while the FSS and PF scores did not improve significantly (p>0.05). In Group-B patients, the mean FSS, PF and MF scores improved significantly (p<0.01) from baseline score after 8 weeks of treatment with L-carnitine along with L-LT₄ treatment. FSS, PF and MF scores of Group-B patients reduced significantly (p<0.01) compared to Group-A patients after 8 weeks of treatment. FSS, PF and MF scores improved in 88.9%, 77.8% and 47.2% cases respectively in Group-B compared to 20%, 14.3% and 5.7% cases in Group-A. L-carnitine was well tolerated and no severe adverse event was recorded.

Conclusion: The results suggest that, administration of L-carnitine along with L-T₄ in hypothyroid patients significantly reduced physical and mental fatigue.

IMC J Med Sci 2019; 13(2): 008. EPub date: 15 January 2020. DOI: https://doi.org/10.3329/imcjms.v13i2.45286

Address for Correspondence: Dr. Farjana Akhter, Assistant Professor, Department of Pharmacology, Green Life Medical College, 31 & 31/1 Bir Uttam K.M. Shafiullah Sarak (Green Road), Dhaka, Bangladesh. Email: [email protected]