Secondary Causes for Low Bone Mineral Density Common

Many postmenopausal breast cancer survivors had low vitamin D, high parathyroid hormone

24 june 2009-- Many postmenopausal breast cancer survivors may have secondary causes of low bone mineral density that are potentially treatable, according to research published online on June 22 in the Journal of Clinical Oncology.

G. Bruce Mann, Ph.D., of the Royal Women's Hospital in Victoria, Australia, and colleagues analyzed data from 200 women -- median age at diagnosis, 62 years -- who'd been diagnosed with breast cancer within the previous five years. Subjects' bone mineral density (BMD) was checked, and blood samples were tested for serum calcium, vitamin D, thyroid function, and parathyroid hormone.

The researchers found that roughly 47 percent of the women had osteopenia and 12.8 percent had osteoporosis. Many had insufficient (37 percent) or deficient (27 percent) vitamin D, and 21 percent had higher than normal parathyroid hormone concentrations. Six women had primary hyperparathyroidism (PHPT) and two had recent surgery for the condition, while 27 had secondary hyperparathyroidism from vitamin D deficiency and six had normocalcemic hyperparathyroidism. Of the patients with low BMD and hormone receptor-positive cancer, the authors note that 8 percent had recent or new PHPT.

"Secondary causes of osteoporosis should be sought and corrected, particularly in patients with hormone receptor-positive breast cancer and low BMD. Vitamin D should be measured and supplemented if low; repeat testing is appropriate to confirm adequate vitamin D replacement. Calcium levels should be checked, PHPT should be specifically sought if calcium levels are high, and PHPT should be treated appropriately," the authors conclude.

Two co-authors reported financial associations with Novartis Pharmaceuticals.

Abstract
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BEER AND BONE STRENGHT

11 may 2009--A couple of glasses of beer or wine every day is good for your bones, The Sun reported. The Daily Express also covered the story, saying scientists found stronger associations between higher bone mineral density and beer and wine drinkers compared to spirit drinkers. However, the scientists also warned that binge-drinking damages bones and makes them weaker.

This research concluded that there is a stronger association between bone mineral density (BMD) and beer or wine intake relative to drinking spirits, and this indicates that bone health is affected by ingredients other than alcohol. It should not be interpreted to mean that alcohol should be drunk for stronger bones. The results that found an assocation with higher BMD are based on an analysis that only included some of the study participants. In this case, a cautious interpretation of the results is warranted.

Where did the story come from?

The research was carried out by Professor Katherine L Tucker from the Jean Mayer US Department of Agriculture Human Nutrition Research Centre on Aging at Tufts University in Boston, and colleagues from the US, UK and Thailand. The work was supported by several grant bodies, including the United States Department of Agriculture, the National Institutes of Health, and the National Heart, Lung and Blood Institute. The study was published in the peer-reviewed medical journal The American Journal of Clinical Nutrition.

What kind of scientific study was this?

This was an analysis of data from a cohort study, which investigated how different classes of alcoholic drink might affect bone. The researchers say that a previous study in older women found that moderate alcohol intake was associated with increases in bone density, and was therefore protective against fractures caused by osteoporosis. Alcoholism is already known to have negative effects on bone.

The researchers had data from the population-based Framingham Offspring cohort study. This study originally began in 1948 and aimed to look at risk factors for heart disease. In 1971, the adult children of the original participants and their spouses were recruited to take part in further studies, which consisted of a series of questionnaires, an examination and tests every four years. In the fifth and sixth study visits (covering the periods 1991–1995 and 1995–1999), there were 2,919 participants (1,280 men and 1,639 women, aged 29–86 years) with bone mineral density (BMD) measurements available. It is this data that the researchers analysed. The researchers had complete data on the alcohol intake and bone density at three hip sites and the lumbar spine in 1,182 men, 1,289 postmenopausal women and 248 premenopausal women, aged between 29 and 86 years.

The participants usual dietary intake was assessed by a validated 126-item food frequency questionnaire. At the two visits, one in the early 1990s and the other in the late 1990s the participants were asked to complete the questionnaires for their intake throughout the previous year. The average intake from the two questionnaires was used to estimate servings of beer, wine and spirits (liquor) per day. The servings were small by present standards: one serving represented a 356ml glass, bottle, or can of beer, one 118ml serving of wine (red or white) or one 42ml shot of spirits.

A range of other details were collected to allow the researchers to adjust for these in their analyses. These included age, sex, smoking, use of osteoporosis medication, BMI, height, physical activity, and intakes of calcium, vitamin D, magnesium, protein, as well as total energy intakes.

The average age of the participants was 61 years for men, 62 for postmenopausal women, and 48 for premenopausal women. Most people were overweight, and few were smokers.

The researchers also estimated the participants’ average silicon intake from food, beer and wine. They were interested in this because silicon is found in a number of foods, cereals and drink including mineral water and beer. The silicon in beer is found in the form of orthosilicic acid, which is readily absorbed by the body and originates from the husks of barley. The silicon intake was calculated from the dietary questionnaires data by taking average values (mg of silicon) for each food item and adding these together to obtain total silicon intake per person per day.

What were the results of the study?

The researchers reported that the men in their study were predominantly beer drinkers, whereas women were predominantly wine drinkers.

Men who consumed one to two drinks a day of total alcohol or beer had greater bone density at the hip (4.5%) than the non-drinkers (3.4%). Postmenopausal women who drank more than two drinks a day of total alcohol or wine had significantly greater bone density at the hip and spine (8.3%) than non-alcohol drinkers (5.0%).

Men who drank more than two drinks a day of spirits had significantly lower bone density at the hip (3.0%) than those who drank one to two drinks a day of spirits (5.2%).

After adjusting for silicon intake, all intergroup differences for beer were no longer significant. The differences for other alcohol sources remained significant.

The researchers note that power was low, meaning that the study was too small to analyse the premenopausal women separately, and the associations were not significant.

What interpretations did the researchers draw from these results?

The researchers say that this is the first study to look at bone density and intakes of different classes of alcoholic beverages in men and post- and premenopausal women.

They say that the results support earlier observations that moderate alcohol intake may protect BMD in postmenopausal women and older men. The benefits are most apparent from beer and wine, which suggests that factors in conjunction with ethanol may be having the protective effects.

They say that “silicon appears to mediate the association of beer, but not that of wine or liquor, with bone density” and suggest areas that could benefit from further investigation.

The interpretation of this study and any implications for those who drink alcohol are complex. There are anomalies in the findings, which appear to counter the view that alcohol is “good for bones”. For example:

• The effect appears to differ between men and women.
• The effect seems to be different for women before and after the menopause.
• The effect varies according to different types of alcohol.
• Part of the effect can be removed if a statistical adjustment for silicon content of food and drink is made.
• While there are some significant differences between the groups (such as between those men drinking two or more glasses of alcohol compared to no alcohol), when the data was analysed for the trend (i.e. whether increasing alcohol consumption overall is associated with increasing bone density) many of these overall trends are no longer significant. This means that the relationship is probably not a simple linear one between alcohol and bone density.

Although it is possible to speculate about the reasons behind these associations, it is better in principle to interpret these results with caution. This is usually the case with studies like this, which demonstrate a mixture of significant and non-significant effects when the data is cut into small sub groups. Caution is particularly important when some of these sub groups show a benefit for alcohol in terms of bone density (beer in men) and some show a harm (spirits for men, but not women).

Links to the headlines

Booze aid for our bones. The Sun, March 4 2009

Sip beer for stout bones. The Mirror, March 4 2009

Beer is a tonic for the bones. Daily Express, March 4 2009

Links to the science

Tucker KL, Jugdaohsingh R, Powell JP, et al. Effects of beer, wine, and liquor intakes on bone mineral density in older men and women. Am J Clin Nutr (February 25, 2009)

Moderate alcohol intake associated with bone protection

Epidemiological study examines effects of beer, wine and liquor on BMD

BOSTON , 04 mar 2009-- In an epidemiological study of men and post-menopausal women primarily over 60 years of age, regular moderate alcohol intake was associated with greater bone mineral density (BMD). Researchers at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University found associations were strongest for beer and wine and, importantly, BMD was significantly lower in men drinking more than two servings of liquor per day. The results suggest that regular moderate consumption of beer or wine may have protective effects on bone, but that heavy drinking may contribute to bone loss.

"Previous research suggests that moderate alcohol consumption in older men and post-menopausal women may protect against BMD loss, a major risk factor for osteoporosis," said Katherine L. Tucker, PhD, corresponding author and director of the Dietary Assessment and Epidemiology Research Program at the USDA HNRCA. The 2005 Dietary Guidelines issued by the federal government defines moderate alcohol consumption as one drink per day for women and two drinks per day for men.

"Our study also looks at the possible effects of the three alcohol classes, beer, wine and liquor on BMD," Tucker continued. "We saw stronger associations between higher BMD and beer drinkers, who were mostly men, and wine drinkers, who were mostly women, compared to liquor drinkers." The results were published online February 25 by the American Journal of Clinical Nutrition.

Tucker, who is also a professor at the Friedman School of Nutrition Science and Policy at Tufts, and colleagues analyzed BMD measurements taken at three hip sites and the lumbar spine in 1,182 men, 1,289 post-menopausal women, and 248 pre-menopausal women whose parents or in-laws participated in the original Framingham Heart Study. There was not enough data to determine the effects of more than two servings of alcohol per day in post-menopausal women or the effects of daily alcohol consumption on BMD in pre-menopausal women. Participants self-reported their alcohol intake on dietary questionnaires. One serving of beer equaled a glass, bottle or can (356 mL), one serving of wine equaled a 4-oz. glass (118 mL), and one serving of liquor equaled one mixed drink or shot (42 mL).

After adjusting for several other factors that may have accounted for the higher BMD, such as silicon intake, calcium intake and smoking history, the authors still saw an association between higher BMD and moderate alcohol consumption. One of the strongest associations was seen in men who reported consuming one or two servings of total alcohol (a combination of beer, wine and liquor) or one or two servings of beer per day. Hip BMD in this group was significantly greater compared to non-drinkers.

In contrast, the authors observed significantly lower BMD at the hip and spine in men who consumed more than two servings of liquor per day compared to men who consumed one or two servings of liquor per day. "There is a body of research showing alcoholism is devastating to bones," Tucker said. "It's a major risk factor for osteoporosis. No one should depend solely on alcohol to maintain bone health."

The authors hypothesize that the silicon found in beer is contributing to the higher BMD scores in the men who reported consuming one or two servings of total alcohol or beer per day, citing previous studies finding silicon has greater bioavailability as a liquid. It is less clear why liquor and wine might protect BMD.

"We cannot say definitively what component of these alcoholic drinks might be beneficial to bone health because our findings are from an observational study, as opposed to a clinical trial," Tucker said. "Future studies might dig deeper into patterns of alcohol consumption, as we relied on a self-reported dietary questionnaire. Another component of data worthy of exploration is whether the antioxidants found in wine, such as revesterol or polyphenols, have a protective effect on bone in addition to other health benefits."

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The study was supported by a USDA contract and grants from the National Institutes of Health (NIH). Co-authors Ravin Jugdaohsingh and Jonathan J. Powell, at the Rayne Institute, St. Thomas' Hospital, London, UK, have an active grant from the charitable foundation of the Institute of Brewing and Distilling. Co-author Supannee Sripanyakorn is sponsored by a studentship from the Government of Thailand and Jugdaohsingh is sponsored by a fellowship from The Frances and Augustus Newman Foundation.