Breaking News:Osteoporosis: what the public needs to know – The Hindu– What Just Happened

Osteoporosis literally means ‘porous bone’, a condition where bones become thin, weak, fragile, and susceptible to fractures on trivial injuries.  

Fractures are painful, take time to heal, reduce mobility and cause a decline in the quality of life, dependency, withdrawal from social interactions, isolation and depression. Fractures of the hip in the elderly can be lethal – the immobility that they cause predisposes patients to clots in the leg veins, which could migrate and block blood vessels in the lungs. The economic burden of hip fractures is considerable, and time spent in the hospital is comparable to time spent for a heart attack or cancer.  

Worldwide, one in two women above the age of 60 and one in three men above the age of 70 have osteoporosis. In Indians, the problem occurs earlier – above age 50 in women and above age 60 in men. With longevity increasing in India, osteoporosis is emerging as a major public health issue. 

Osteoporosis is a ‘silent disease’ – a fracture after a minor fall is often the first symptom. Even after a fracture has been treated, the underlying osteoporosis is often not recognised or treated. Early diagnosis is important because currently available interventions can partially reverse the process and prevent fractures.  

Bone physiology  

The resorption of bones and the formation of bones occur continuously throughout life. This process, called remodelling, maintains the integrity of bones and gives them the ability to bear different mechanical stresses. From birth to age 25, formation exceeds resorption — the skeleton steadily grows stronger and reaches a state called ‘peak bone mass’, the maximal calcium density. From age 25 to about age 45 in Indian women, bone density remains steady – resorption equals formation. However, in women after menopause and in men after age 60, resorption exceeds formation – bones become progressively more fragile.   

The commonest sites of fragility fractures are the wrist, back bone or the upper end of the thigh bone. Spinal crush fractures are often silent and lead to a stooped posture. Sometimes such fractures cause back pain in between the shoulder blades. Many attribute the pain to aches and pains of old age and disregard it. The pain may resolve but the stoop progressively worsens. About 25% of women with a vertebral fragility fracture will have another within one year.  

Risk factors and diagnosis

Risk factors include being over the age of 55, early or premature menopause and a thin body build (BMI<19). Parental history of hip fracture and previous fragility fractures are also important risk factors. Inadequate calcium intake and sun exposure, smoking and alcohol consumption, long-term use of corticosteroids and anti-seizure medication also increase the risk. Many hormonal disorders – diabetes mellitus, overactivity of the thyroid, parathyroid or adrenal cortex and reduced function of the pituitary gland can cause severe osteoporosis 

The most accurate method of determining bone mineral density (BMD) is the DEXA (dual-energy X-ray absorptiometry) scan. This fast, non-invasive low radiation technique measures bone density vulnerable sites. The results, expressed as a ‘T-score’, indicate the extent to which the results in a patient deviate (standard deviation score) from peak bone mass. 

Anyone can use the simple FRAX tool, available on the internet – simply fill in a questionnaire and the risk of serious osteoporotic fractures in the next 10 years is displayed. If a DEXA scan is available, the BMD of the neck of the thigh bone can be factored in, to provide a more accurate risk assessment. Your doctor uses this tool to decide on the need for specific anti-osteoporotic medications. 

Nutrition and bone health 

Prolonged mild deficiency of calcium and vitamin D causes bone thinning that is indistinguishable from osteoporosis.  

Calcium is the building block of the skeleton – 99% of all the calcium in our body resides in the bones. This reservoir maintains calcium levels in the blood within a narrow normal range – calcium in blood is essential for healthy nerve and muscle function and for many vital cellular biological processes.  

Nutritional calcium deficiency is very common in Indians. If the calcium demands of the body are not met by adequate dietary calcium intake, calcium is released from the bone into the circulation and in the long run, bones become weak.  

Dairy products are the most readily available and absorbed sources of calcium. Other sources are millets such as ragi, green vegetables, nuts, soy curds (tofu) and whole fish with soft, edible bones. 

Even when there is normal calcium intake, some intestinal diseases may interfere with intestinal calcium absorption and cause calcium deficiency. Vitamin D, a fat-soluble vitamin, enhances calcium absorption from the gut and also promotes deposition of calcium in the bone. By enhancing muscle strength and balance, Vitamin D reduces the risk of falls as well.  

The skin, when exposed to UVB rays in sunlight, makes Vitamin D. However, exposure of the scalp and extremities to sunlight for at least 20-30 minutes between 10 AM and 4 PM is necessary to get enough vitamin D. Excepting farmers and fisherfolk, most others do not get this amount of sunlight exposure. Therefore, Vitamin D deficiency is rampant in all age groups in our country. Dietary sources of vitamin D include: fatty fish (e.g., salmon, cod, mackerel and sardines), egg yolk and liver. Milk does not contain enough vitamin D. 

Recommended vitamin D intakes vary by age and are highest in growing children, during pregnancy and lactation. 

Proteins are also necessary to build the collagen framework of bone. An optimal intake of high-quality protein is essential for good bone-health – inadequate intake during childhood, adolescence and adult life (common in vegetarians) contributes to poorer peak bone mass, earlier onset and faster progression of osteoporosis. Too much protein intake, however, can harm bones – a build-up of acidic substances leaches calcium from bone.  

Fall prevention 

In osteoporotic individuals, falls precipitate fractures. Therefore, fall prevention is essential to avert fractures. Good vision and hearing are vital to prevent falls. Elderly individuals need to have annual visual assessments, and problems such as cataracts and glaucoma need to be treated. Tackling hearing impairment with good hearing aids can also help prevent falls. 

Elderly individuals also need to achieve and maintain good muscle strength and balance. Weight-bearing exercises, strengthening of anti-gravity muscles of lower limbs and exercises to improve reflexes and balance (eg. walking in a straight line) can also help prevent falls. 

Most falls in the elderly occur while standing up – individuals need to steady themselves in the seated position for some time, get up slowly with support and only then start moving around. 

Avoiding sleeping pills and other drugs (eg. antihistamines} that impair reflexes is very important. Blood pressure medication that decreases standing BP can make individuals dizzy and cause falls, and should be replaced with safer alternatives. 

Paying attention to the home’s interior, ensuring non-slippery floors, free passage without obstacles; installing grab-bars and handrails where appropriate, is also very important. Elderly patients with imbalance should be taught how to use a walking frame to avoid falls. 

Treatment options   

First and foremost, ensure adequacy of calcium and vitamin D. Women with premature menopause (before age 40) should consult doctors early to start on calcium, vitamin D and other medications to counter osteoporosis.  

Those diagnosed to be at high risk of fractures are usually treated with medicines to inhibit bone resorption (Bisphosphonates, Denosumab), to promote bone formation (Teriparatide) or do both (Romosozumab). The response to treatment takes 3-5 years and annual follow-ups are necessary.

This article was first published in The Hindu’s e-book Care and Cure. 

(Dr. Seshadri M.S. is senior consultant, physician and endocrinologist, Naruvi Hospitals, Vellore. mandalam.seshadri@gmail.com; Dr. Sai Krishna Chaitanya P. is consultant endocrinologist, Naruvi Hospitals , Vellore. saikrishna.p@naruvihospitals.com)