New research suggests that having a bone mineral density below normal (osteopenia) or having an even greater loss of bone density resulting in fragile porous bones (osteoporosis), which are both caused by a lack of calcium, are more common in men and women who also have benign positional vertigo than in their peers without this condition.
"These findings suggest a problem with calcium metabolism in people with vertigo," said senior author Dr Ji Soo Kim, from Seoul National University College of Medicine in Korea.
"Women most often have their first case of vertigo in their 50s, when they are also having a drop in bone mass due to loss of oestrogen. Oestrogen is one of the main hormones that influence calcium and bone metabolism."
According to the report in the journal Neurology, the cause of benign positional vertigo is largely unknown. Prior research, however, has suggested that calcium deposits and, therefore, bone metabolism may play a role in benign positional vertigo.
What the study revealed
The condition is characterised by the onset of vertigo that occurs following a change in body position, such as going from a seated to a standing position.
In the present study, which featured 209 benign positional vertigo patients and 202 comparison subjects, the results of bone mineral density testing showed that benign positional vertigo patients were at greater risk for both osteopenia and osteoporosis.
After adjusting the findings for the effects of age, gender, alcohol use, smoking, and abnormally high phosphate levels, the authors found that osteopenia and osteoporosis doubled and tripled the risk of benign positional vertigo, respectively.
In women 45 years of age or older, bone loss was greater in those with recurrent benign positional vertigo than in those with a first episode, the report indicates.
The findings, the authors conclude, suggest that calcium metabolism is disturbed in subjects with benign positional vertigo. The results are also consistent with those from an earlier, smaller study showing that bone mineral T scores are lower in older women with the condition than in their unaffected counterparts. – (Reuters Health, March 2009)
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