Measuring bone strength and preventing fractures
Osteoporosis is a condition associated with the menopause that causes weakening of the bones. Bones can become fragile and therefore more prone to fracture. Osteoporosis affects more than three million people in the UK alone. One of the most effective ways of preventing and even treating low bone density is by taking hormone replacement therapy (HRT). Oestrogen plays a fundamental role in bone health. HRT also protects the intervertebral discs in the spine. These discs are crucial for cushioning the vertebral bones and preventing crush fractures. The exact type of HRT treatment has to be tailored to each woman’s needs to provide a completely integrated approach.
Hormone replacement therapy (HRT) and bones
Osteoporosis is identified by measuring bone mineral density (BMD), as low bone density means that action should be taken. Bone density is assessed by Dual Energy X-ray (DXA) scanning, usually at the lower back (lumbar spine) and/or the hip. It is interesting to note that bone density is as strong an indicator risk factor for fracture risk, as high blood pressure is for future stroke and high cholesterol is for a heart attack.
At least one in three women and one in five men over the age of fifty will sustain a fracture in their remaining lifetime that could be related to osteoporosis The most common sites of fracture are the wrist (Colles Fracture), the shoulder, the vertebrae (small bones of the spine) and the hip but really almost any bone fracture can be related to osteoporosis perhaps with the exception of the skull!
Who should be assessed for osteoporosis and fracture risk?
Any male or female over the age of 40 years with clinical risk factors will benefit from a risk assessment using the risk calculators. The risk factors for both men and women include:
- Family history of osteoporosis or fractures
- Early menopause
- Previous fracture over the age of 40 years
- High alcohol intake
- Overactive thyroid or parathyroid glands
- Eating disorders (especially anorexia nervosa)
- Chronic liver or kidney disease
- Limited mobility due to neurological disease
- Frequent fallers
- Coeliac disease or poor absorption of food
- Chronic steroid (glucocorticoid) use
- Rheumatoid arthritis
- Ankylosing spondylitis
Active weight bearing exercise, good healthy nutrition and access to adequate reserves of Vitamin D (derived from sunlight, the diet or a supplement) is very important for maintaining good bone health. Gauging the right level of sunlight exposure so as to maintain good vitamin D levels without excess risk of skin cancer is problematic. Guidelines published by the Scientific Advisory Committee on Nutrition (SACN) recommend a Reference Nutrition Intake (RNI) for vitamin D of 10 μg/d (400 IU/d) for everyone in the UK aged 4 years and above. In practice this will mean that many adults will need to take a 400 iu vitamin D supplement.
It would be ideal if improving lifestyle factors alone could reduce fractures. However, for those people with significant increased risk of fracture, especially in those diagnosed with osteoporosis by DXA scan, drug therapy will usually be advised. Unfortunately, calcium supplements (with or without vitamin D) are not sufficient and there is increasing anxiety that higher doses of calcium may be associated with increased risk of cardiovascular events such as a heart attack and stroke. While this risk is not proven preventative therapy with calcium and vitamin D alone in women around the time of the menopause is not recommended and other approaches are preferable.