​Osteoporosis, the "porous bone" disease, is on the rise in Singapore but as many as one in two patients could be taking potent medicines that may do little for their condition. The long-term medication given to most patients to help stem bone loss may not work well for those with what is described as secondary osteoporosis, doctors have found, following a study. They are recommending tests to identify the real reasons why different people are afflicted, so that patients can be treated appropriately.

"I see many patients labelled as having just garden-variety osteoporosis due to menopause and ageing," said Dr Manju Chandran, Senior Consultant and Director of the Osteoporosis and Bone Metabolism Unit, Department of Endocrinology at the Singapore General Hospital (SGH), a member of the SingHealth group, who led a recent study into the subject.

Patients with primary and secondary osteoporosis require different medication

For years, many patients with osteoporosis have been prescribed medicines to slow down bone loss or stimulate bone formation. For many, she said, "this is as useful as pouring water into a leaky bucket". She suggests separating patients into two groups:

  • Those with primary osteoporosis associated with ageing and post-menopausal bone loss in women with depleted oestrogen levels; and
  • Those with secondary osteoporosis precipitated by factors ranging from vitamin D deficiency to the excretion of too much calcium in the urine, and thyroid problems.

It is the patients in the second group who need more appropriate medication, and most likely will not improve if given standard treatment that works for those with primary osteoporosis. Osteoporosis causes the bones to become weak and brittle, so that a fall or even mild stresses like bending over or coughing can cause a fracture. It has no symptoms in the early stages, and is diagnosed through a bone density scan.

Fractures resulting from osteoporosis are on the rise here, given the ageing population and sedentary lifestyle. In fact, osteoporotic hip fracture rates here are among Asia’s highest.

Study on secondary osteoporosis

In 2010, about 2,200 people aged 50 and above were hospitalised for hip fractures. More than one in five with such injuries die within a year. Yet, local and regional information on the condition has been sparse, said Dr Chandran, who is also a consultant at the SGH Endocrinology Department and president of the Endocrine and Metabolic Society of Singapore.

The study she led, the first of its kind in South-east Asia on secondary osteoporosis, looked at 400 patients. It found that secondary osteoporosis occurred in six out of 10 older men with the disease, and in almost 45 per cent of post-menopausal women.

Stressing the lack of awareness of the condition, she said: "Even specialists tend to put patients on standard medications and send them on their way without looking further at the underlying causes." The research was published in the journal Archives of Osteoporosis in 2012. Noting that it would be expensive and unnecessary to screen patients for the entire spectrum of causes, Dr Chandran suggests limiting it to the most common ones.

Click on page 2 for more information on secondary osteoporosis.

Ref. T12