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Osteoporosis, a bone disease affecting seniors and menopausal women is a growing concern causing over 8.9 million fractures each year worldwide (Johnell et al, 2006). In India, there are an estimated 25 million people who may be suffering from osteoporosis. Both men and women are affected with the disease at an earlier age compared to the West (Malthora and Mittal, 2008).
Defining the Disease
Osteoporosis is a disease of the bone where density progressively decreases over the years. Those who suffer from the condition are at high risk of falling and injuring themselves severely resulting in hip fractures. Worldwide, approximately 28-35% of people, over 65 years and above fall annually (Blake et al, Prudham, and Campbell et al) and the incidence rises to 32-42% in seniors over the age of 70 (Tinetti et al, Downton & Andrews, and Stalenhoef et al).
Is It Genetic?
There are several causes of osteoporosis. Although certain factors such as age, medications and disease and lack of essential vitamins and mineral for bone development are at the forefront of why osteoporosis occurs, there is also the belief or theory that genetics play a role. In women, who are at a higher risk of contracting the disease especially at an older age, the prevalent threats include sedentary lifestyle, cigarette smoking and an excessive intake of alcohol.
Studies that Support Osteoporosis is Hereditary
There are several studies and researches that point to the DNA makeup as one of the culprits when it comes to the bone disease. A senior person whose family history includes bone and hip fractures has a bigger risk of going through or suffering from the same condition. In addition, those with a small body structure and frail bones are at a higher risk of lower bone density even at an early age.
Ralston in the study, ‘Genetic Determinants of Osteoporosis’ explained the genes and genetic variants that are linked to the condition and the management of bone mass. The research also identified the genetic markers in assessing fracture risks.
Another study by Estrada et al identified 56 genetic variants (bone mineral density loci) and determined 14 loci are linked to fracture risks. It gave a better understanding of the genetic structure of bone mineral density and how it affects fracture susceptibility.
Twin and family studies have also demonstrated that 50% to 85% of the differences in BMD is due to genetic variances (Peacock et al, 2002).
Race and Ethnicity
Another factor is racial makeup, with Caucasians or Asians more likely to get osteoporosis than other ethnic groups. Cauley in her study, ‘Defining Ethnic and Racial Differences in Osteoporosis and Fragility Fractures’ revealed that race and ethnicity have some bearing on the incidence of fractures, with the highest rates recorded in white women. Among men, there is not much variance with other ethnic and racial groups, but the incidence of bone fracture is higher in white men than those of Asian or African descent. (Cummings et al, 2002).
Hochberg in his study, ‘Racial Differences in Bone Strength’ affirms that fracture risk is higher among whites than blacks in the US. This was due to the greater bone strength (mass, porosity and composition as well as damage) among blacks compared to whites. Stronger bones in blacks are attributed to the development of a sturdier skeleton and lower bone loss during adulthood.
Management of Osteoporosis
Osteoporosis is strongly linked to genetics, but its incidence can be prevented. Loss of bone density can be averted by consuming adequate amounts of calcium and vitamin D for stronger bones. Other methods include engaging in weight-bearing exercises, and avoiding certain drugs that affect bone loss. Women also have the option to start estrogen replacement therapy which can reduce bone density.Osteoporosis is a disease of the bone where density progressively decreases over the years. Those who suffer from the condition are at a high risk of falling and injuring themselves severely resulting in hip fractures. Worldwide, approximately 28-35% of people, 65 years and above, fall annually (Blake et al, Prudham, and Campbell et al) and the incidence rises to 32-42% in seniors over the age of 70 (Tinetti et al, Downton & Andrews, and Stalenhoef et al).