Osteoporosis is a condition which is characterised by low bone mineral density. As a result, it causes bones to become brittle, weak and greatly increases the risk of fractures as the condition progresses.

Prevalence

According to Osteoporosis Australia, approximately 4.74 million Australians over 50 years of age are currently diagnosed as having osteoporosis, osteopenia (precursor to osteoporosis) or poor bone health. It is also suspected that osteoporosis is under-diagnosed and many Australians with the condition go undetected. As improvements in detection methods and public awareness increases, it is expected that this number may increase significantly over the next decade.

Furthermore, due to the nature of the condition causing bone weakness, there is also a large quantity of osteoporotic-related fractures which occur each year. In 2013, there were 144,000 recorded fractures which were specifically associated with osteoporosis or osteopenia.

It is estimated that over the next decade osteoporosis, osteopenia and their related fractures will place an additional $33.6 billion dollar burden on the Australian healthcare system.

Pathophysiology

Osteoporosis can occur at any age, however, is far more likely to occur later in life – particularly in individuals over 50 years old. Similar to other tissue within the body, bones are constantly being reabsorbed, recycled and redeposited. This allows minerals such as phosphorous and calcium to be redistributed throughout the skeletal system to help maintain, repair and adapt bone as necessary to suit our lifestyles. Typically, both males and females reach their peak bone density around 30 years of age and after this stage bone reabsorption starts to occur faster than new bone is deposited, as shown in figure 1. This results in a gradual loss of bone mineral density as we age and can eventually lead to osteopenia or osteoporosis if bone mineral density drops too low. It should also be noted that after approximately 50 years of age, women experience an accelerated level of bone mineral loss due to menopause which causes a decrease in circulating oestrogen (hormone) levels and places females at an increased risk of developing osteoporosis.

Bone Mass vs Age

Figure 1) Bone mass over time according to gender.
Image source: Anatomy & Physiology, Connexions Web site. http://cnx.org/content/col11496/1.6/, July 31, 2014. – OpenStax College

Risk Factors

Risk factors associated with the development of osteoporosis include:

  • Low calcium intake
  • Low vitamin D levels
  • Poor sun exposure
  • Family history of osteoporosis
  • Post-menopausal females
  • Hormone levels
  • Some medications
  • Excessive alcohol intake
  • Smoking
  • Obesity

Signs, Symptoms and Detection

As previously mentioned, osteoporosis can go undetected as signs and symptoms are not always present or obvious in individuals who have the condition. Although, some indicators may still be present such as:

  • Loss of height
  • Back pain – due to vertebral fractures
  • Hunched/stooped posture
  • Bone fractures – especially if they occur from minor trauma

Osteoporosis/osteopenia can easily be detected via a non-evasive procedure called a DEXA (dual energy X-ray absorptiometry) scan which measures bone density via the use of low-energy X-rays. If you are concerned that you may have or may develop osteoporosis/osteopenia please consult your physician.

Prevention and Management

Prevention and management strategies are very similar when it comes to osteoporosis. Maintaining a healthy diet and active lifestyle are key factors in the fight against osteoporosis. The following are some helpful tips to improve your bone health and assist with preventing/managing osteoporosis:

  • Ensure you are ingesting an adequate level of calcium (approximately 1,200mg; 3-4 serves of dairy products) and maintain a healthy diet. Please consult a dietician for more information and to address your specific dietary requirements.
  • Maintain adequate vitamin D levels. It is recommended that Australians achieve 5-15minutes of sun exposure 4-6times per week in order to maintain appropriate vitamin D levels. Furthermore, individuals should avoid direct sunlight during 10am-2pm due to dangerous levels of ultraviolet light exposure.
  • Perform regular physical activity. Weight-bearing activities which place force/stress on the skeletal system stimulate bone growth and are very important during the first two decades of life when the majority of our bone is developed. Examples of weight-bearing activities include: resistance/weight training, brisk walking, dancing, yoga etc. Please consult an exercise physiologist or physiotherapist for more information.
  • Avoid excessive alcohol and caffeine intake.  Alcohol consumption of more than two standard drinks per day has been linked with an increased risk of developing osteoporosis as well as an increase in fracture rates. Similarly, high levels of caffeine intake have also been identified as a risk factor for osteoporosis and caffeine should be limited to a maximum of three cups of tea or coffee.
  • Avoid/cease smoking. Smoking has been associated with an increased risk of developing osteoporosis.