"The maintenance of healthy bone in human adults occurs through a process called 'bone remodeling,'" said Dennis A. Chakkalakal, research scientist at the Omaha Veterans Affairs Medical Center, associate professor in the department of surgery at Creighton University, and sole author of the review. "At any given time during adult life, and in various parts of the skeleton, small portions of the 'old bone' are removed by cells called 'osteoclasts,' and new bone is formed by cells called 'osteoblasts.' In a healthy person, the two activities are in balance so that there is no net loss of bone."
However, Chakkalakal says that chronic and heavy drinking can disrupt the balance by suppressing new bone formation.
"The empty space created by normal bone-removing activity is inadequately filled by newly formed bone," said Chakkalakal. "This process continues at other skeletal sites during the next remodeling cycle. The cumulative effect of this process during several remodeling cycles is manifested as measurable bone loss over a period of just a few years."
"Many people know about alcohol's effects on the liver and the damage it can cause to this organ after years of heavy drinking," said Terrence M. Donohue, Jr., VA Research Career Scientist at the Omaha VA Medical Center and professor of internal medicine at the University of Nebraska Medical Center. "Considerably fewer people know about alcohol-induced bone disease."
Key highlights of the study include:
- "Alcohol-induced bone disease" refers to two consequences of chronic alcohol abuse: bone loss (also known osteopenia), which results in increased fracture risk; and deficient bone repair.
- Alcohol-induced osteopenia is distinct from post-menopausal osteoporosis and disuse osteoporosis.
- Human, animal and cell-culture studies show that alcohol's toxic effects on osteoblast activity are dose-dependent.
- Alcohol can suppress synthesis of an ossifiable matrix, which interferes with fracture healing.
- Alcohol-induced bone loss is associated with abnormalities of cell dynamics in bone marrow.
"In both cases, alcohol adversely affects osteoblast activity, thus suppressing new bone formation needed in both normal bone remodeling and fracture healing," he said. "We need future studies that focus on molecular mechanisms by which alcohol inhibits osteoblast activity. We also need a closer examination of the effects of other factors such as malnutrition, smoking and lack of physical activity as there are very few studies that evaluate the effects of these factors. Finally, we need more definitive, well-designed studies to sort out the age- and gender-related differences in the effects of moderate and excessive consumption of alcohol."
Abstience Best Choice With FracturesDonohue said that the evidence also supports the choice of abstinence from alcohol. "The review underscores the importance of abstinence from alcohol consumption by patients alcoholics or teetotalers with fractures and who may want to drink during their convalescence."
Source: The review of research was published in the December 2005 issue of Alcoholism: Clinical & Experimental Research.