Osteoporosis: definition, identification and prevention

What is osteoporosis?

Osteoporosis is a condition that weakens bones, making them fragile and prone to break and it affects more than three million people in the UK. It is identified by measuring bone mineral density (BMD), as low bone density means that bones may have lost strength. 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 a risk factor for excess fracture risk, as high blood pressure is for future stroke and high cholesterol is for a heart attack.

At least one in 3 women and 1 in 5 men over the age of 50 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, fingers and toes!
 

How can risk of fracture be assessed?

Calculating the risk of fracture is based on a combination of clinical risk factors and bone density measurement. There are two different online clinical risk factor calculators which work out an individual’s 10-year risk of major osteoporotic fracture and hip fracture alone and both have been “approved” by the National Institute of Health and Care Excellence (NICE). These are:
 
Q-Fracture  - this has the advantage of including many clinical risk factors but has the disadvantage of not linking to BMD.
 
FRAX - this has far fewer risk factors but crucially allows inclusion of BMD of the hip. It also links directly to the National Osteoporosis Guideline Group (NOGG) recommendations of thresholds for BMD measurement and treatment.
 

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 Smokers
Eating disoprders 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) user
Rheumatoid arthritis Ankylosing spondylitis
 

Preventing Osteoporosis

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 but for those people with significant increased risk of fractures, 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.

Hormone replacement therapy (HRT)

One of the most effective ways of preventing and even treating low bone density is by taking hormone replacement therapy (HRT). There is good evidence that oestrogen is protective of the bones as well as the intervertebral discs, which are crucial for cushioning the vertebral bones and preventing crush fractures. There has been much debate regarding the safety of HRT, but the evidence is clear that if started around the time of the menopause, it can ensure good long term bone health as well as having many other positive effects such as treating hot flushes, sweats, low mood, low energy and vaginal dryness. HRT can be taken in many different forms such as gels, patches and tablets. The exact type is tailored to each woman’s needs to provide a completely integrated treatment.


 

A loss of appetite resulting in weight loss. Anorexia nervosa is a psychological illness in which self-starvation leads to weight loss. Full medical glossary
Inflammation of one or more joints of the body. Full medical glossary
A fluid that transports oxygen and other substances through the body, made up of blood cells suspended in a liquid. Full medical glossary
An element that forms the structure of bones and teeth and is essential to many of the body's functions. Full medical glossary
Abnormal, uncontrolled cell division resulting in a malignant tumour that may invade surrounding tissues or spread to distant parts of the body. Full medical glossary
The basic unit of all living organisms. Full medical glossary
A substance present in many tissues and an important constituent of cell membranes although high concentrations of a certain type of cholesterol in the blood are unhealthy. Full medical glossary
An abbreviation for dual energy X-ray absorptiometry. Full medical glossary
A viral infection affecting the respiratory system. Full medical glossary
An organ with the ability to make and secrete certain fluids. Full medical glossary
The death of a section of heart muscle caused by an interruption in its blood supply. Also called a myocardial infarction. Full medical glossary
A substance produced by a gland in one part of the body and carried by the blood to the organs or tissues where it has an effect. Full medical glossary
Abbreviation for hormone replacement therapy, the administration of female hormones in cases where they are not sufficiently produced by the body. Full medical glossary
intermittent claudication Full medical glossary
One of the tough pads of fibre and cartilage that separate the vertebrae and act as cushions to absorb forces on the spine. Full medical glossary
One of two bean-shaped organs that are located on either side of the body, below the ribcage. The main role of the kidneys is to filter out waste products from the blood. Full medical glossary
A large abdominal organ that has many important roles including the production of bile and clotting factors, detoxification, and the metabolism of proteins, carbohydrates and fats. Full medical glossary
The part of the back between the lowest ribs and the top of the pelvis. Full medical glossary

The time of a woman’s life when her ovaries stop releasing an egg (ovum) on a monthly cycle, and her periods cease

Full medical glossary

Associated with the nervous system and the brain.

Full medical glossary
A hormone involved in female sexual development, produced by the ovaries. Full medical glossary
onychogryphosis Full medical glossary
A condition resulting in brittle bones due to loss of bony tissue. Full medical glossary
Lying face-downwards. Full medical glossary
rheumatoid arthritis Full medical glossary
septic arthritis Full medical glossary
Any sudden neurological problem caused by a bleed or a clot in a blood vessel. Full medical glossary
A gland in the neck that produces hormones with a role in controlling metabolism. Full medical glossary
Relating to the urinary tract. Full medical glossary
The muscula passage, forming part of the femal reproductive system, between the cervix and the external genitalia. Full medical glossary
Relating to blood vessels. Full medical glossary
Affecting the vertebrae, the bones of the spine, or the joints between them Full medical glossary
Essential substances that cannot be produced by the body and so must be acquired from the diet. Full medical glossary
A type of electromagnetic radiation used to produce images of the body. Full medical glossary