Muscling in on breaking bones

It may not be a high profile disease, but the effects of osteoporosis can be devastating, writes COLETTE SHERIDAN

THERE SHOULD be a clearer focus on educating Irish women on preventative health factors to curb the prevalence of osteoporosis, according to a new study from the University of Limerick.

The Effect of Behavioural Risk Factors on Osteoporosis in Irish Women, headed by Dr Niamh Cummins from the Graduate Entry Medical School at UL, was sparked by the increasing problem of osteoporosis, or brittle bone disease.

One in three Irish women over the age of 60 will suffer a fracture and about one in five men. Osteoporosis in men is on the rise caused by increasingly sedentary lifestyles.

“There is a lot of work done on the genetic aspect of osteoporosis which is obviously really important,” says Cummins. “Between 60-80 per cent of bone density is genetically determined. If your mother or father has osteoporosis, there’s a pretty strong chance that you will get it. You can’t control that. But what you can control is behavioural factors.

“Even during school physical education classes, teachers should focus on increasing the level of weight-bearing physical activity.”

Cummins points out that most people think menopausal or post-menopausal women are most susceptible to osteoporosis as their oestrogen levels drop, reducing the bone protective hormone. That’s not always the case.

Osteoporosis, says Cummins, can be rooted in or exacerbated by certain behaviours. “Smoking is quite a significant factor in pre-menopausal and post-menopausal women. Obviously, people are aware of the risks of smoking in terms of lung cancer. The problem with smoking is that it increases the breakdown of oestrogen.

“And there are other smoking-related factors. Smokers tend to have lower body weight and a lower BMI [Body Mass Index]. This is a risk factor for osteoporosis. A healthy BMI starts at 18.5 and goes up to 25.”

Diet is another factor. “A lot of women avoid full fat milk and full fat cheese because of the perception that they’re fattening. But the avoidance of dairy products means that a lot of women are calcium deficient.”

Cummins says that the most striking finding in her study of 189 women (average age 44 years) is that 84 per cent of post-menopausal women were found to be deficient in calcium.

“That’s a massive figure and this group is the one that is already most at risk from the disease. By not meeting their calcium requirements, they are further pre-disposing themselves to osteoporosis.”

Osteoporosis, often called the “silent disease”, “isn’t a high profile disease like cancer. But it can have effects that are just as devastating. With something like a hip fracture, you could stay in hospital for two weeks and it can take six months to a year before you have full mobility again.

“It affects independent living. Some people never recover from a fracture. Sometimes, there can be quite high mortality following a hip fracture. Interestingly, mortality in men following hip fractures is higher than in women. Men find it hard [to recover from a hip fracture].”

In the diagnostic world, Cummins says there is a move away from just measuring bone density “which was the gold standard for many years. Bone density is the mineral phase of bone. Bones also have a protein phase. There is increased awareness that the protein phase is actually very important.

“What happens with osteoporosis is that the protein phase deteriorates first. When we talk about the protein phase, the term used is ‘bone quality’.”

Cummins says “the race is on for whoever can first find a good tool for diagnosing bone quality. This will help in identifying clinical risk factors for osteoporosis. More commonly, we’re seeing the use of Frax which is an online fracture risk calculator.”

Using Frax, a doctor can make an informed decision as to the likelihood of a fracture in a given period of time. “I think this is a very positive development. It’s a more holistic approach. A doctor can decide whether treatment is needed in a 10-minute consultation. Earlier identification is key,” she says.

Cummins says that her study “is not massive. There was also the fact that we were trying to assess the life time physical activity of the women, something that is notoriously difficult to assess when you’re dealing with women of 70.”

For younger women who are afraid they will develop osteoporosis, Cummins recommends circuit training and basketball. “Anything involving jumping and impact is good. Also, weight lifting is a good exercise.”

Cummins says “it’s quite difficult” to quantify the extent to which exercise will reduce the risk of osteoporosis. “But it does make a difference.”

Diet is also important with leafy green vegetables recommended as well as bony fish and dairy products.

A recent European study claimed that calcium supplements double the risk of heart attack.

Cummins says she is unaware of the study but advises consulting one’s doctor before making any decisions about calcium supplements.