Risk Factors for Osteoporosis

Bed rest

Bed rest leads to rapid loss of bone so it is best kept to a minimum if possible. If it is necessary to stay in bed for extended periods of time, physiotherapy and simple exercises will help reduce bone loss.

Caffeine intake

Drinking copious cups of coffee or strong tea during the day has been linked to osteoporosis. It is difficult to state a maximum level of intake, although a ceiling of two to four cups a day is generally recom­mended. Beware of caffeine in other products, partic­ularly canned colas and some health drinks.

Diet lacking in calcium

Adequate amounts of calcium in the diet are essential to maintain bone strength. Women over the age of 40 need about 1,500 milligrams per day if they are not taking HRT. Women taking HRT have a lower requirement of 1,000 milligrams per day as the oestrogen itself helps strengthen bone. After the age of 60, daily requirements fall to 1,200 milligrams.

History of amenorrhoea

Amenorrhoea, when menstrual periods cease, is associated with insufficient oestrogen to maintain the normal menstrual cycle, leading to oestrogen deficiency. In primary amenorrhoea, the first menstrual period occurs several years later than the usual age of 13 but subsequent menstruation is normal. In other cases, secondary amenorrhoea, menstruation starts at the normal age, but then the periods stop. Anorexia nervosa, an increasingly common cause, leads to a marked loss of weight and altered body image.

Young gymnasts are also at risk from over-exercising. More recently, treatments for conditions such as endometriosis (when the womb lining is found in tissues outside the womb) stimulate a ‘medical menopause’ by switching off the ovarian production of oestrogen with a consequent drop in oestrogen levels. All these factors can increase the individual woman’s lifetime risks of oestrogen deficiency illnesses.

Hyperthyroid disease

An overactive thyroid increases the resting metabolic rate, speeding up the normal process of bone formation and breakdown which can lead to osteoporosis. Hyperthyroidism also puts an extra burden on the heart, which beats faster and more forcefully.

Sunlight

Elderly women often stay indoors and get little sunlight on their skin. In certain cultures women are heavily covered in dark clothing and, particularly if they live in Europe, minimal daylight reaches their skin. Sunlight is very important because it stimulates the production of vitamin D in your skin. This vitamin aids the absorption of calcium from food, helping bones to stay strong. Only 15 to 30 minutes in daylight each day is necessary.

Pregnancy

The more times you have been pregnant, the lower your risk of osteo­porosis, because each pregnancy produces a surge in oestrogen. Women who have never been pregnant will not have had this oestrogen surge and their lifetime exposure to oestrogen will be lower, increasing long-term risks of osteoporosis.

Previous fracture(s)

Previous fractures can suggest existing osteoporosis, increasing your chances of further broken bones.

Racial origin

Women of black racial origin achieve a 10 per cent greater peak bone mass than white women, so white racial groups are more likely to develop osteoporosis.

Use of steroids

Prolonged use of oral steroids, over 5 milligrams each day, is linked to osteoporosis. Steroids are usually prescribed for conditions such as severe asthma or autoimmune diseases. In these conditions the body’s protective mechanisms are disrupted and normal tissue is seen as a foreign body which should be destroyed. Short-term courses of steroids, for one or two weeks, are not associated with increased risks unless frequently required.

If you are on long-term steroid therapy, speak to your doctor to discuss possible alternatives and ways in which you can prevent osteoporosis developing.

Risk Factors for Heart Disease

Diabetes

Diabetes affects blood vessels, increasing the risk of their becoming narrowed by deposits of the fatty substance atheroma. This in turn may lead to blockage of arteries by blood clots causing a coronary thrombosis (heart attack) or stroke. After the menopause women with diabetes have three to five times the risk of a heart attack and twice the risk of a stroke when compared with women without diabetes. These risks may be reduced by careful control of diabetes, avoiding obesity and taking HRT.

High blood pressure

Regular blood pressure checks are important to identify women with raised blood pressure, because high levels are linked to heart disease and strokes.

The average blood pressure is 120/80 millimetres of mercury but it rises with age so that a measure­ment of 140/90 is acceptable in the postmenopausal group. Sometimes a treatable cause for high blood pressure is found but, in most cases, it runs in families with no clear identifiable reason. If you are overweight or smoke, losing weight or stopping smoking may be suffi­cient to control the blood pressure.

If your blood pressure is high on at least three consecutive occasions, your doctor will probably recommend that you take daily treatment to reduce it. Many people find daily drugs difficult to take as they usually feel otherwise well – high blood pressure, in itself, does not give rise to any symptoms. However, it is important to realise that treatment is aimed at prevention – stopping the development of heart disease is a much more effective medicine than treating a heart attack.

High cholesterol

Cholesterol levels below 5.2 milli-moles per litre (mmol/l) indicate a low risk of heart disease, levels above 6.5 mmol/l denote a greater risk. The average measurement of cholesterol is around 5.6 mmol/l. A well-established link exists between heart disease and high cholesterol in men, but for women an association remains uncertain and the risk appears to diminish with increasing age. However, there is evidence to suggest that lowering cholesterol reduces heart disease. Modifying your diet is the best treatment; drugs are available but many have unwanted side effects. Routine tests of cholesterol are controversial because other risk factors, such as obesity or smoking, need to be taken into account. Many do-it-yourself kits produce unreliable results so go to your doctor or well-woman clinic for a more reliable test.

Personality

Aggressive and ambitious people -so-called type A personalities -appear to have twice the risk of heart disease compared with the calmer type B personalities.

Previous heart attack

As with angina, a previous heart attack shows the presence of existing heart disease. The already weakened heart is more susceptible to further damage

Special cases Arthritis

Increasing evidence suggests that HRT reduces the impact of arthritis by increasing bone density. This is true for both osteoarthritis and rheumatoid arthritis; although HRT does not reverse the process of the disease, it is a useful adjunct to conventional therapy.

Alzheimer’s disease

Results of recent studies suggest that long-term use of oestrogens can reduce the risk of developing Alzheimer’s disease and may also reduce the severity of the condition.

Smoking

Smoking is a risk factor for heart disease and osteoporosis, but it is included under this separate heading because its effects are even more wide reaching. More than 9,000 women die each year from lung cancer directly related to smoking. It is also linked to cancers of the cervix and bladder. Smoking affects the way that your body uses oestrogen, so that oestrogens are broken down at a faster rate than usual. Women who smoke have an earlier meno­pause, by one or two years, than women who do not smoke, so they are at greater risk of oestrogen deficiency. Campaigns to stop smoking have been very successful in the overall population but unfortunately smoking is on the increase in young women, the group most vulnerable to its long-term effects.

Early menopause

Women who have an early meno­pause – before the age of 45 – are considered to be a ‘high-risk’ group for the consequences of oestrogen deficiency, because they are particularly susceptible to osteo­porosis and heart disease. An early menopause is caused by failure of normal ovarian function, which has been linked to certain genetic disorders. Treatment with radio­therapy or chemotherapy for con­ditions such as leukaemia may also induce ovarian failure. The diagnosis is made on the basis of menopausal symptoms and is confirmed by a simple blood test to measure hormone levels.

Preventive action against oes­trogen deficiency should begin as soon as possible. Women choosing to take HRT are advised to continue treatment at least until the age of 50 but may wish to take it for longer.

Hysterectomy

Removal of both ovaries at hyster­ectomy induces an immediate menopause which can be treated with oestrogen replacement or alternatives. Studies show that women who have this ‘surgical’ menopause develop more severe menopausal symptoms than those who have a ‘natural’ menopause. This may be because the body does not have the usual time to adapt to hormonal fluctuations.

In most hysterectomy operations the ovaries are not removed, but even this can trigger a menopause about four or more years earlier than the natural menopause. Without the evidence of irregular periods or other changes in the menstrual cycle, it can be difficult to assess the onset of the menopause, although hot flushes and other symptoms are sufficient indicators.

Young women whose periods have ceased

Periods often cease in women who exercise excessively or who are anorexic and whose oestrogen levels fall. Many doctors consider that this group should be offered HRT to protect against the long-term con­sequences of oestrogen deficiency.