L-carnitine reduces severity of physical and mental fatigue and improves daily activities in the elderly.

Chronic fatigue syndrome is a disabling illness that afflicts the elderly and influences their daily activities. (1) The evaluation and treatment of fatigue has been fraught with frustration and oftentimes, a sense of failure. Patients diagnosed with fatigue are often disappointed when advised to merely, "get more rest."

Carnitine plays an important role in the production and distribution of cellular energy. (2) We evaluated the effect of exogenous L-carnitine on fatigue and on the activities of daily living (ADL) of 80 elderly subjects (Table 1). Forty-one subjects were given L-carnitine (4 g/d) and the remainder were given a placebo throughout a 180-day period.

Fatigue was evaluated by Wessely and Powell scores (3) and by the Fatigue Severity Scale. (4) Functional assessment was performed using the Katz index (ADL) (5) and the Lawton scale (IADL). (6)

Patients treated with L-carnitine showed a significant decrease in physical fatigue (P = 0.000), mental fatigue (P = 0.000), fatigue severity (P = 0.000), improvement of activities of daily living (ADL, P = 0.000) and instrumental activities of daily living (IADL, P = 0.01). At the completion of the treatment, a significant difference between the two groups was found for the following parameters: Physical fatigue -7.2 versus -0.5 (P = 0.000); mental fatigue -3.3 versus 0.1 (P = 0.000); fatigue severity -22.3 versus 0.1 (P = 0.000); ADL 0.8 versus 0.1 (P = 0.000); and IADL 1.40 versus -1.10 (P = 0.01) (Table 2).

There are few effective treatment options for patients with chronic fatigue. (1,7) Plioplys and Plioplys (8) observed clinical improvement in 12 of 18 patients with chronic fatigue syndrome following levocarnitine treatment. In a study by Tomassini et al, (9) acetyl-L-carnitine reduced fatigue in multiple patients compared with amantadine. After L-carnitine administration in our patient group, we observed a reduction in the severity of both physical and mental fatigue as well as improvement in the patient's activities of daily living. We hypothesize that the reduction in both physical and mental fatigue in our patients was due to improved energetic metabolism in the myocardial, musculoskeletal, and cerebral tissues.

Mariano Malaguarnera, AP

Antonino Di Mauro, MD

Pia Maria Gargante, MD

Department of Senescence, Urological and Neurological Sciences

University of Catania 

Catania, Italy

Liborio Rampello, AP

Department of Neurosciences

University of Catania

Catania, Italy

References

1. Pistone G, Marino A, Leotta C, et al. Levocarnitine administration in elderlysubjects with rapid muscle fatigue: effect on body composition, lipid profileand fatigue. Drugs Aging 2003;20:761-767.

2. Rebouche CJ, Seim H. Carnitine metabolism and its regulation in microorganism and mammals. Annu Rev Nutr 1998;18:39-61.

3. Wessely S, Powell R. Fatigue syndromes: a comparison of chronic postviral fatigue with neuromuscular and affective disorders. J Neurol Neurosurg Psychiatry 1989;52:940-948.

4. Krupp LB, LaRocca NG, Muir-Nash J, et al. The fatigue severity scale: application to patients with multiple sclerosis and systemic lupus erythematosus. Arch Neurol 1989;46:1121-1123.

5. Katz S, Downs TD, Cash HR, et al. Progress in development of the index of ADL. Gerontologist 1970;10:20-30.

6. Lawton MP, Brody EM. Assessment of older people: self-maintaining and instrumental activities of daily living. Gerontologist 1969;9:179-186.

7. Neri S, Pistone G, Saraceno B, et al. L-carnitine decreases severity and type of fatigue induced by interferon-alpha in the treatment of patients with hepatitis C. Neuropsychobiology 2003;47:94-97.

8. Plioplys AV, Plioplys S. Amantadine and L-carnitine treatment of chronic fatigue syndrome. Neuropsycobiology 1997;35:16-23.

9. Tomassini V, Pozzilli C, Onesti E, et al. Comparison of the effects of acetyl L-carnitine and amantadine for the treatment of fatigue in multiple sclerosis: results of a pilot, randomised, double-blind, crossover trial. J Neurol Sci 2004;218:103-108.

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Table 1. Patients' baseline characteristics (mean values [+ or -] SD)

                             Carnitine group      Placebo group

Age                           78 [+ or -] 7.6      79 [+ or -] 6.4
Sex (M/F)                     20/21                20/19
Height (cm)                  158.2 [+ or -] 7.6   160.1 [+ or -] 7.1
Weight (kg)                   68.2 [+ or -] 9.1    67.6 [+ or -] 8.4
Systolic arterial pressure   160 [+ or -] 20.1    158 [+ or -] 20.4
  (mm Hg)
Diastolic arterial pressure   87.2 [+ or -] 10.1   87.7 [+ or -] 10.3
  (mm Hg)
Heart rate (bpm)              83 [+ or -] 10       81 [+ or -] 12

Table 2. Mean values ([+ or -] SD) of fatigue scores and activity daily
in the two groups

                                            Carnitine
                               Before treatment   After treatment

Physical fatigue (0-16)        13.6 [+ or -] 2.1   6.4 [+ or -] 2.0
Mental fatigue (0-10)           7.7 [+ or -] 2.1   4.4 [+ or -] 1.5
Fatigue Severity Scale (9-63)  50.1 [+ or -] 7.8  27.8 [+ or -] 10.2
ADL (0-6)                       4.1 [+ or -] 0.8   4.9 [+ or -] 1.1
IADL (0-8)                      3.7 [+ or -] 2.6   5.1 [+ or -] 2.3

                                             Placebo
                               Before treatment   After treatment

Physical fatigue (0-16)        13.1 [+ or -] 2.3  12.7 [+ or -] 2.4
Mental fatigue (0-10)           7.8 [+ or -] 1.8   7.2 [+ or -] 1.9
Fatigue Severity Scale (9-63)  50.2 [+ or -] 7.6  48.7 [+ or -] 6.4
ADL (0-6)                       4.2 [+ or -] 0.9   4.3 [+ or -] 0.8
IADL (0-8)                      3.6 [+ or -] 2.8   3.8 [+ or -] 2.4

ADL, activities of daily living; IADL, instrumental activities of daily
living.