Osteoporosis — a condition which causes the structure of bones to become thin (the name means 'porous bones') — affects around three million people in the UK. Those with the condition may find that their bones break more easily, and not only through high-trauma incidents such as major falls. A simple fall from a standing height, or even lifting heavy bags of shopping or heavy boxes, may cause a vertebral fracture in the back, for instance. Osteoporosis most commonly affects women post-menopause, a time when oestrogen levels fall and bone loss becomes more rapid.

Currently there is no cure for osteoporosis, but various interventions can make a big difference to patients says Dr Neil Gittoes, Consultant Endocrinologist and Associate Medical Director at Queen Elizabeth Hospital, Birmingham. First of all, those diagnosed with the condition should consider making some lifestyle changes. “We know that a calcium-rich diet can be effective, as is an intake of vitamin D, either through diet or sun exposure,” says Gittoes. “Weight-bearing exercise three or four times a week is also important, as is cutting out smoking — which is bad for your bones — and lowering your alcohol intake. These are general interventions that individuals can make for themselves at an early stage.”

 

Drug therapies

 

Various drug therapies are used to treat osteoporosis, the most common of which is a bisphosphonate called alendronic acid, which can be prescribed by GPs. This reduces the risk of bone fracture by around 50 per cent and is generally taken as a tablet once a week. There are downsides, however. “It must be swallowed first thing in the morning on an empty stomach and washed down with a large glass of water,” says Gittoes. “Then the patient should wait an hour before eating, because the tablet is generally not well absorbed and can cause ulceration and indigestion if it gets caught in the gullet.” Actonel, another bisphosphonate, is also commonly prescribed by GPs.

If patients experience side-effects with alendronic acid or Actonel, other 'second line' drugs are available, including Zoledronic acid, an intravenous infusion, and Denosumab, a sub cutaneous (just under the skin) injection. Both are taken once a year, are usually well-tolerated and their efficacy is broadly the same. “There are certain nuances to both drugs which may make them more effective in certain patients,” explains Gittoes. “For instance, Denosumab can be given to individuals with varying degrees of kidney function problems.”

Hormone Replace Therapy (HRT) may be another useful intervention for osteoporosis patients. “We know from evidence that HRT has a beneficial effect on bones,” says Gittoes. “Oestrogen levels fall past the menopause, causing a net loss of bone; whereas giving the oestrogen back rebalances it. HRT can also reduce the risk of fracture — but once it is stopped that beneficial effect wears off quickly.” HRT can also be used for male patients whose testosterone levels are low. “If a man is having fractures, and his testosterone levels are low, on balance it would be reasonable to consider giving testosterone replacement therapy,” says Gittoes. “Although, in parallel, a bisphosphonate, such as alendronic acid, might also be prescribed.”

 

New developments

 

All of these drugs, however, only prevent further bone loss. Yet a drug called Teriparatide may be able to reverse the condition as it is able to build fresh bone. “In an ideal world, we would be keen to reverse the pathology of osteoporosis — and Teriparatide does have that capability,” says Gittoes.

Over the last decade or so, there have been exciting developments in the treatments available for osteoporosis, says Gittoes. “There are different classes of drugs moving through the research portfolio at the moment, and one of these builds new bone. Over a 10 - 15 year timeframe, we may be in a position to have an array of drugs that can be used sequentially — one that builds bone and another that retains bone. If so, we'll be able to do more than we can now to reverse the pathology and give people a better quality of life, preventing pain and loss of function.”