Osteoporosis is a chronic condition, normally associated with aging, which affects all the bones in the body. Bone mineral density is a measurement of the density of bones. This number is lower then what is normally expected when you suffer from osteoporosis and the micro-structure of the bone is weaker than normal. Bones which have lost their mineral density are at much higher risk for fracture from low trauma or from compression in the spine. And, although bone fractures are usually not life threatening, individuals who suffer a bone fracture as a result of osteoporosis have a 20% chance of mortality in the first year following the break. (1)
The World Health Organization has defined osteoporosis as a bone mineral density 2.5 standard deviations below peak bone mass in a 20 year old of the same sex measured by DXA (a radiological procedure). The DXA is the gold standard in diagnosis of osteoporosis. (2)
More important than treatment for osteoporosis is prevention because it is the best way to reduce the risk of fracture. Bone mass density peaks between the ages of 25 and 35. Physical activity has the greatest impact toward the development of strong bones during the teen years. Adults can help maintain and increase bone mass density by one or 2% using physical activity as well. If the value of your peak bone mass is high at age 25 then the bone loss you suffer as you age will be functionally lower.
The underlying mechanism in the formation of osteoporosis is the difference between bone reabsorption (which normally occurs) and bone formation. During osteoporosis the bone is a reabsorbed more quickly or is formed more slowly than is normal. Most cases of osteoporosis do not result from in adequate calcium level, but instead from other factors such as a lack of vitamins, cigarette smoking, sedentary lifestyle, family history and and age.
Once an individual has been diagnosed with osteoporosis, restoration of a microstructure of the bone is difficult to repair. Although there are medications which have been shown to increase bone mass density they do not make an impact on the micro-structure and therefore the stability of the bone itself. Bone loss can be reduced but it can not be replaced.
There are two types of bone: trabecular and cortical. The trabecular bone appears spongelike and is located in the core of the long bones. This helps to provide stability in the bone and is where bone formation occurs. Cortical bone is a hard exterior shell which provides the majority of the stability.
At the time that osteoporosis is diagnosed, doctors find that the trabecular bone is the section that suffers the greatest amount of bone loss. The hip bone, spine and wrists are the area of the body which have the most trabecular bone and are at the greatest risk for bone fractures.
If an individual suffers a fracture related to osteoporosis, it places them at a higher risk for developing another fracture. An individual who has a hip fracture will often result in decreased mobility and an additional risk of embolism that can travel to the lungs or heart. In the year following a hip fracture 20% of those sufferers will die. Individuals who suffer from vertebral compression fractures or spinal degeneration will experience dowagers humps making it more difficult for them to breath.
Although individuals who suffer from, or have been diagnosed with, osteoporosis have an increased mortality rate (death rate) due to complications of fracture more people actually die with the disease rather than of the disease.
While there are risk factors that can be controlled or preventative measures that can be taken there are some that cannot be changed such as a family history of osteoporosis, a history of bone breakage as an adult, advanced age or European or Asian ancestry. Risk factors that can be controlled are the use of steroids, cigarettes, alcohol use, low calcium and vitamin D intake, and poor health.
Osteoporosis will cross genders, age and socio-economic lines. All individuals are at risk, some more than others. By making a change in your overall health and taking preventative measures many individuals are able to offset the diagnosis, delay the progression or prevent the disease altogether.