Chronic skeletal myopathy may affect one third of chronic alcohol misusers. It is generally accepted that abstinence allows partial recovery, and that continued high-dose ethanol consumption progressively deteriorates muscle function. However, the effect of low-dose ethanol consumption in alcoholic myopathy has not been studied. We studied 58 chronic alcoholic male patients with biopsy-proven chronic alcoholic myopathy over 5 years. We evaluated ethanol intake, biochemical and nutritional parameters, and assessed muscle strength. Eighteen patients who remained abstinent showed marked improvement in muscle strength. As expected, the 19 patients who persisted in high-dose ethanol consumption further diminished in their muscle strength. In the 11 patients who maintained low-dose (≤60 g ethanol/day) `controlled' drinking, muscle strength improved (p=0.003), despite no change in nutritional and exercise status. There is a dose-dependent recovery in muscle strength according to the degree of ethanol consumption, and moderate controlled drinking of up to 60 g ethanol/day still allows improvement in muscle strength. Chronic alcoholism treatment.
About one third of long-term high-dose alcohol misusers develop skeletal myopathy, which appears in a dose-dependent manner, and manifests clinically as proximal muscle weakness, pain and atrophy.
Once established, alcoholic myopathy usually reverses provided complete abstinence is achieved.
By contrast, continued high-dose alcohol abuse is accompanied by further deterioration in muscle strength and the appearance of histological damage to the muscle.
In the treatment of alcoholic patients, the first goal is to achieve complete abstinence from ethanol intake. However, abstinence is not always possible, and a significant percentage of alcoholics are only able to reduce their intake to ≤60 g of ethanol a day (`controlled' drinking).
Since little is known about the consequences of `controlled' drinking on the natural history of chronic skeletal myopathy,
we studied a large series of chronic alcoholics with skeletal myopathy, to evaluate the effects of different doses of ethanol on muscle function. Muscle strength, measured by myometry, was taken as the paradigm of skeletal muscle function.
Treatment of chronic alcoholism
Patient selection and baseline studies
Over a 2-year period, we consecutively selected male patients seen in the Alcohol Unit of the Hospital Clínic of Barcelona. This unit treats only ambulatory patients who seek assistance in terminating their dependence of alcohol, but who have no signs or symptoms of other diseases. Patients with other maladies, or overt alcohol-related disorders such as liver cirrhosis, heart failure or malnutrition, are referred to other clinics. Patients with HIV infection, neoplasm, consumption of illicit drugs or with causes of myopathy other than alcoholism were not selected for the study.
Patients who complained of muscle weakness or myalgia, or those with a significant reduction in muscle strength (<,20 kg)
were submitted to a deltoid muscle biopsy in the non-dominant arm. Cryostat sections of biopsy specimens were processed by standardized histological and histochemical methods, as previously described.
Alcoholic myopathy was diagnosed according to standard histological criteria and classified as mild, moderate, or severe.
No patient objected to inclusion in the study. The study protocol was approved by the Institutional Review Board and informed consent for the various procedures was obtained from each patient.
Of the 84 patients initially evaluated, 68 chronic alcoholics with biopsy-proven skeletal myopathy were enrolled in the study. All subjects were Caucasian men of Spanish origin who lived with their families in or around Barcelona and had histories of stable employment. No homeless people were included in the study. A detailed history, including ethanol intake, dietary habits and neuromuscular symptoms was obtained by two different interviewers (JF-S and JR) using a structured questionnaire. Alcohol dependence was diagnosed according to DSM-IV.
A history of alcohol consumption in terms of type of alcoholic beverage, average daily consumption, yearly amount and frequency of ethanol intake was computed. Data were confirmed in consultation with family members. Basic biochemical and nutrition assessment included serum muscle enzymes, anthropometrical and protein nutritional parameters. Evaluation of muscle strength was performed at the deltoid level of the non-dominant arm with an electronic myometer (Penny &, Giles), five times over a period of 20 min, measuring force against resistance using a standardized method.
To assess any influence of physical activity on muscle strength along the study, the extent of daily exercise involving the shoulder girdle and upper extremities at baseline and over the follow-up period were computed. Patients and controls reported the time spent on physical activity at work and at home, as well as sports played, and were categorized in a scale score of 0–3, as previously reported.
After baseline evaluation, an ambulatory detoxification programme was proposed to all patients. Patients were then prospectively followed over a period of 5 years. Appointments were scheduled every 6 months during the first 2 years and once a year thereafter, including clinical evaluation, nutritional status, and assessments of ethanol intake and physical activity. Functional evaluation of muscle strength was performed by myometer as described at baseline and was used as the functional marker of alcoholic myopathy. Ethanol intake was assessed by two different interviewers in consultation with the family members throughout the 5-year period, and patients were classified as: (i) abstainers, (ii) consumers of 20–60 g/day (`controlled' drinkers), (iii) consumers of 61–99 g/day, or (iv) consumers of ≥100 g/day. To assess the reliability of self-reports of ethanol abstinence, the values of serum aminotransferases, gammaglutamyl transpeptidase and mean corpuscular erythrocyte volume were determined periodically and at the end of study, as was the concentration of ethanol in urine. Ten patients who changed their ethanol intake group over the follow-up period were not further evaluated and were excluded from the study.
Standard statistical methods from the SPSS Statistical Analysis System V4.0+(SPSS, Chicago) were used.
Univariate comparisons were performed using analysis of variance and the χ
test. Differences between baseline and follow-up values were analysed by the Student's paired t-test. All variables are expressed as means±SEM.
Chronic alcoholism treatment guidelines
Fifty-eight chronic alcoholic men with biopsy-proven skeletal myopathy completed the follow-up. Their mean age was 46.1±1.3 years (range 22–64 years), and a daily ethanol intake of 206±8 g (range 100–290 g/day) was reported over a period of 22±7 years, giving a mean lifetime dose of ethanol of 25.4±1.2 kg of ethanol/kg body weight. The drinking pattern was of continuous ethanol intake as a part of everyday life, and only occasional binges were reported. These patients consumed ethanol mainly in the form of wine, beer, and brandy, and less frequently as anisette or gin. None used illicit drugs throughout the study.
Demographic, laboratory and nutritional data are shown in Table 1 ). Throughout the follow-up period, patients did not exhibit changes in biochemical and nutritional parameters except for significant improvement in the tricipital skin fold, albumin, gammaglutamyl transpeptidase and aminotransferases (Table 1 ). The degree of histological myopathy at baseline was similar in all groups (Table 2 depicts the differential evolution of muscle strength according to the degree of ethanol consumption over the 5-year follow-up period. Abstinent patients (n=18) showed a significant improvement in mean muscle strength from 18.0±1.2 to 24.4±0.7 kg (p<,0.001). By contrast, heavy drinkers (n=19, ≥100 g/day) further reduced muscle strength over this period, from 21.8±1.1 to 18.0±1.1 kg (p=0.001). Patients consuming 61–99 g ethanol/day (n=10) did not show significant changes in muscle strength. However, it was interesting and unexpected that muscle strength improved in alcoholic patients with biopsy-proven alcoholic myopathy who continued low-dose `controlled' drinking (20–60 g/day) (n=11), rising from 18.5±1.2 to 22.3±1.4 kg (p=0.003). This improvement was non-significantly greater in the abstainers (6.4 kg vs. 3.8 kg, p=0.10). The degree of histological myopathy at baseline did not influence on the changes in muscle strength along follow-up. Physical activity over follow-up was similar to baseline in all four groups of patients. Five patients who changed their working occupation showed no significant modification in their physical activity score (Table 2