Osteoporosis – Who is at risk

Osteoporosis definition: Osteoporosis is a condition of fragile and brittle bones. It is a skeletal disorder characterised by compromised bone strength predisposing a person to an increased risk of fracture.

There are many factors that can influence a person’s risk of developing osteoporosis. Some of these factors are beyond our control, such as family history or gender. Other factors can be decision influenced, such as choosing whether or not to smoke. And for other risk factors, which are modifiable, actions can be taken to reduce risk, such as incorporating regular exercise.

Bone is an active organ. There is a continual process of bone building and breakdown. Peak bone mass is achieved in our late teens and early twenties. Everyone experiences age-related loss of bone as part of the normal ageing process. Bone health is determined by the amount of peak bone mass attained and then the amount of bone loss that occurs due to several reasons including genetics, hormones, medications, lifestyle and diet. Therefore, any factor that can influence the peak bone mass attainment, and/or the influence bone loss throughout life will increase risk of developing osteoporosis.

Risk factors which influence the achievement of peak bone mass

The peak bone mass achieved is largely determined by genetic makeup. This of course, cannot be changed. Other actions, however, can be taken to reach the peak bone mass that this genetic makeup allows.

Diet and nutrients

Consuming a healthy diet with adequate:

• Calcium
• Vitamin D  

Lifestyle

• Regular exercise
• Smoking and drinking alcohol may also reduce peak bone mass.

Absence of menstrual periods

For teenage girls and women in their early twenties, with irregular (oligomenorrhoea) or absent periods (amenorrhoea), attainment of their peak bone mass is jeopardised as oestrogen has a protective effect on the bones. There are many reasons why absent periods or irregular periods may occur including hormonal factors, (e.g. thyroid disorders, high prolactin levels, polycystic ovarian syndrome), medications, weight loss, stress and excessive exercise. A diagnosis of the cause of the absence or irregularity of the periods should be elucidated and appropriate treatment should be started to ensure regular menstrual cycles.

Factors that increase the risk of osteoporosis and factors that influence bone loss after the attainment of peak bone mass

Genetics

A family history of osteoporosis and fractures is one of the greatest risk factors

Gender

Women have a higher incidence of osteoporosis than men. This is because men start with a higher peak bone mass and are not subject to the accelerated bone loss that precedes and immediately follows the menopause. This rapid acceleration of bone loss after menopause, when oestrogen levels decrease rapidly, is up to 5 per cent per year increases for 4-8 years. After this time women will continue to lose bone at about 1 per cent per year, the same rate as men, indefinitely.

Medical conditions

• Chronic digestive disorders which affect the absorption of nutrients including celiac disease, Chrohn’s disease and ulcerative colitis
• Hyperthyroidism (over-active thyroid) or hyperparathyroidism (overactive parathyroid glands). Excessive thyroxine replacement (thyroxine replacement is essential for many individuals and it is important to have levels tested by your medical practitioner).
• Chronic liver or kidney disease
• Rheumatoid Arthritis
• Organ transplant recipients

Low oestrogen states

• Premature menopause (before the age of 40) due to the longer period of time following menopause and loss of the protective effect of oestrogen.
• Absence of periods for 6- 12 months (other than pregnancy)

Medications

• Corticosteroid therapy (doses of prednisolone greater than 5-7.5 mg daily, or equivalent dose of another glucocorticosteroid for greater than 2 months; any dose of glucocorticosteroid in people aged >65
• Long term Gonadotrophin-releasing hormone (GnRH) agonists or analogues , which may be taken for endometriosis

Dietary factors

• High caffeine intake, greater than 3 caffeinated beverages per day reduces calcium absorption
• Long term low dietary calcium intake
• Excessive alcohol (less than 2 standard drinks per day may actually be beneficial for bone health)
• Eating disorders (anorexia nervosa , bulimia)

Lifestyle Factors

• Smoking (smokers generally have lower body weight and bone mineral density. Female smokers have lower circulating oestrogen levels and menopause occurs 1.5-2 years earlier than in non-smokers). However, if women stop smoking before menopause, risk of a hip fracture is decreased by approximately one quarter. So it is never too late to stop smoking.
• Sedentary lifestyle
• Immobilisation
• Lack of sunlight/Low Vitamin D
• Low body weight

Risk Factors for Osteoporosis