Osteoporosis – the bone-thinning disease – affects some three million people in the UK. Post-menopausal women are by far the commonest sufferers, although osteoporosis can also affect younger women, men and children.
Typically strong and resilient in childhood, bones have a dense, ivory-like outer casing or cortex, enclosing an inner core (also known as medulla) of soft marrow filling up the gaps and spaces of the spongy interior. Like all living tissue, bone is able to absorb and utilise a range of proteins and mineral salts from the bloodstream for renewal and repair. Bones generally stop growing in length after the age of 16-18 years, but their density and strength increase until the late 20s.
From the age of around 35 onwards, however, bones become weaker and more fragile due to a loss of mineral salts. This loss intensifies in women as their oestrogen levels fall, reaching a peak at the menopause when the production of this hormone from the ovaries ceases altogether.
Thinned-down bones are weaker and more fragile, and the full-blown disease of osteoporosis is responsible for approximately 230,000 fractures yearly in the UK. The most serious of these is a fractured neck of femur (thigh bone) because the long period of immobility during recovery increases the risks of life-threatening conditions such as pneumonia, and DVT (deep vein thrombosis) with subsequent blood clot on the lungs (pulmonary embolism), heart attacks and strokes. Between 20 and 35 per cent of sufferers between the ages of 75 and 90 die within 12 months of fracturing their hip joint, around 80 per cent of whom are women.
This can be achieved with a dual energy X-ray absorptiometry (DEXA) scan which provides the gold standard means of diagnosing osteoporosis. It expresses bone mineral density in terms of standard deviations (a statistical unit) below that of a young adult reference population. The unit used is presented as a T-score, and the World Health Organisation (WHO) has established the following guidelines:
- T-score of 1.0 or greater = normal
- T-score between –1.0 and –2.5 = low bone mass
- T-score of –2.5 or less = osteoporosis.
X-rays are helpful for confirming fragility fractures e.g. of the ribs or vertebrae. However, they are relatively insensitive to the identification of early disease, requiring a bone mass loss of at least 30 percent before picking up diagnostic changes.
The available treatments to reduce risk of fracture act in different ways, either to reduce resorption or to increase formation of bone. The commonest medications used are bisphosphonates, which reduce the resorption of bone as it normally occurs. The best-known, sodium alendronate (Fosamax), is known to be very effective at preventing bone loss but tends to irritate the food pipe (oesophagus). It is given once a week on an empty stomach, and the patient is advised to remain upright for an hour after taking it. It often causes heartburn, however, and many patients cease to take it for this reason. Other types of bisphosphonates are available.
Hormone Replacement Therapy (HRT), has been shown to reduce the risk of fracture and can be used to prevent or treat osteoporosis in women under the age of 60 who have no contraindications to the use of HRT.
Calcium compounds such as carbonate and citrate, and calcium + vitamin D combinations are also widely prescribed to help improve bones. These are the building blocks of bone and their effect is best when they are given alongside other treatments such as bisphosphonates and HRT.
Better bone health
Exercise, sunshine and diet are all needed for healthy bone growth and maintenance.
Exercise – walking and gentle aerobics are excellent for bone health because they promote the entry of calcium into the bone mass where it is used for improved strength and growth.
Nutrition – a healthy and balanced diet is fundamental to bone (and general) health because it supplies the protein, carbohydrate and fat, vitamins, minerals and other nutrients vital for tissue renewal and growth. This is important during childhood when new bone is being constantly laid down, and also throughout adult life when old bone is broken down and destroyed, and new bone built up to replace it.
Fresh fruit and vegetables supply a vast range of essential minerals and other nutrients needed to maintain a sturdy skeleton. Dairy foods are rich in calcium, and eating them need not increase one’s saturated fat intake because the reduced fat versions supply just as much of this mineral, and often more – weight for weight.
Other sources of calcium include green leafy vegetables such as spring greens, spinach and broccoli, baked beans, dried fruit, bottled mineral water, soya beans, sardines, salmon, nuts, dried beans and sunflower seeds.
Vitamin D is also essential because it enables calcium and phosphorus to be used to form strong bones and teeth. It can be obtained from sunshine and as a supplement. Sunshine on the skin creates vitamin D and the advice is exposure of a reasonable body area for 20 minutes/day from May to October – Remember to apply sunscreen and avoid burning. Vitamin D can also be obtained from food, e.g. milk and dairy products, fish liver oils, sardines, herring, salmon and tuna.
Prevention of falls
This is important for the elderly. Attention to loose mats, wires and other obstacles in the home is necessary, and care in walking out in icy conditions is obvious.
Menopause: Giving you confidence for understanding and action
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This fact sheet has been prepared by Women’s Health Concern and reviewed by the medical advisory council of the British Menopause Society. It is for your information and advice and should be used in consultation with your own medical practitioner.
Reviewed: October 2017
Date of next review: October 2019
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