Doctor’s blog: Diagnosing Osteoporosis is a fashionable trend, a medical fad

It was in the late 1990s that the word ‘osteoporosis’ started appearing in Mainstream Media. Only medical professionals knew the term then but even among us, the interest was passing and casual. It changed in the first decade of the present millennium which was globally observed as the ‘bone and joint’ decade to increase awareness about ‘musculoskeletal’ health. By the end of the decade the Osteoporosis had become a household name. For some, including doctors, it became an obsession.

In medicine, like in all other spheres, there are trends. Osteoporosis became a trendy topic. As a result, there is a deluge of information now on Osteoporosis making it difficult to distinguish between the wheat and the chaff. Similar to other medical trends, business interests, half-truths and even plain fabrications obfuscated the facts.

Take Home Points

· With aging bone mass progressively becomes less.

· BMD estimation is required for quantification of Osteoporosis.

· BMD estimation is not routinely recommended for all post menopausal women/men irrespective of age

· Z score is more scientific than T score measurements

· Mere low BMD on a DEXA scan is not meant to label a person Osteoporotic.

· An active lifestyle and regular exercises with balanced diet are best to prevent/combat osteoporosis. Being slightly overweight actually helps.

· Calcium and Vit D supplements have no role in prevention of Osteoporosis

· Certain commonly-used medications, used indiscriminately, may lead to Osteoporosis.

To put it simply, our bones are made of two components- Osteoid matrix or the background material and the mineral which gives them the structural strength. Lessening of the mineral is called Osteoporosis.

For bones, around 35 years of age is when they are at the peak of their health. The mineral content (referred as bone mineral density or BMD) having reached its peak, then starts progressively diminishing after this age.

Besides age, there are other factors which determine the BMD. Hormonal status, ethnicity, sex, nutrition, physical activity level, certain diseases, certain medications, they all have effect on BMD.

Now that we know that BMD decreases as we grow older (faster in women than in men because of the menopause), the question arises as to how low is low? To declare a value abnormal, we have to first know what is normal.

Like height and weight, all values have a range. In medicine, these values are decided by studying a large number of people, collecting their readings and calculating the Mean. From the mean two standard deviations (SD) on either side of the Mean is the range. By this method about 95 percent of the population is covered in the normal range. The foregoing is elaborated to emphasise that in any test, five percent of people have values that are always outside the normal range. But they are not abnormal.

BMD is generally measured by a test called DEXA scan. It generates a score known as T score to tell us how far the subject has deviated from the Mean. Almost invariably the diagnosis of osteoporosis is based on a T scoreof more than 2.5 SD (Standard Deviation) less than the Mean.

But the Mean in this case is the ‘Mean’ of a 35-year old American male ! It is clearly ridiculous to compare a 70 year old woman with a 35 year old man and diagnose her as suffering from a disease.

A Z score, on the other hand, is age adjusted and therefore a Z score of more than 2.5 SD is truly suggestive of low BMD. Sadly, most cases are diagnosed based on T score with a large number of actually normal people unnecessarily being placed in the abnormal category.

Why should it matter?: Because a weak bone is prone to fracture. Diagnosis of Osteoporosis and probability of a fracture is a complex correlation. Two primary concerns are- can we predict fractures and if so, can they be prevented by therapeutic intervention?

Should you get your BMD checked?Yes and No. Yes- for women above the age of 65, tests may yield some moderate benefit. For post- menopausal women below the age of 65, the test generally helps only if they are in the high risk group namely- have a history of fracture due to trivial trauma, excessive alcohol intake, anorexia, thyroidhormone excess, kidney diseaseand surgical removal of the ovariesetc.

Besides, long term use of certain drugs like anti-seizure medications, chemotherapy, proton pump inhibitors, some Anti-depressants and steroidsalso put a person in the high risk group.

There is no evidence that BMD measurements help men irrespective of age. What is more, BMD report in itself should not be the basis to diagnose Osteoporosis and this in itself cannot predict a fracture.

Can the fracture be prevented?Fracture prevention entails more of fall prevention than Osteoporosis management. From the musculoskeletal point of view, Osteoporosis prevention is more about risk factor (lifestyle and nutritional) management than of drug treatment.

Bone strength depends primarily on loading (read-activity). Bones, like muscles, gain their mass by exercise together with good nutrition. Active lifestyle is the key to combat Osteoporosis. Cessation of smoking and alcohol are also an important lifestyle modification. Balanced diet with adequate calcium is essential. A glass of milk in any form with a mixed Indian diet gives adequate calcium for the daily requirement.

By the way, it may be worth noting that a cup of milk has more calcium in it than in a Calcium tablet.A review by the USPSTF found that the routine use of calcium and vitamin D supplements (or both supplements together) did not reduce the risk of having an osteoporotic fracture in male and female adults living in the community.

Furthermore, the same review found evidence that the combination of vitamin D and calcium supplementation increases the risk for developing kidney stones. So, if you have been convinced that these supplements are necessary, there is a need to review your convictions.

Vitamin D is actively being touted for its benefit on the heart too. The facts are entirely different.

Recently concluded prospective controlled VITAL trial showed that supplementation of vitamin D3 was not effective for primary prevention of cardiac or cancer events among healthy middle-aged men and women.

In otherwise healthy person, for just a low BMD medication in any form, has not been found to be of a significant use.

Those who are on long term use of anti depressants (SSRI) like Prozaic (Fluoxitane) or sertraline and on Proton Pump inhibitors (like Omeprazole, Pantoprazole, Robiprazole) should be aware that these drugs may be a cause of Osteoporosis.

There is a long list of drugs that may be associated with osteoporosis but there is always a trade-off between disease mitigation and side effects. It is a great solace for those who have suffered from body image problem, to know that being overweight is associated with a lower risk of osteoporosis/fracture.