Osteoporosis : Prevention & treatment

Dr Arvind Chopra / Dr Nachiket Kulkarni

Osteoporosis is generally a silent asymptomatic disease in the large majority of patients. It is easy fracture after a mild or minimal injury that increases the suspicion of disease. Osteoporosis is characterised by weak bones which are less dense than normal and break easily after minor injury. This is called fragility fracture. Elderly women with osteoporosis related compressions of the spine vertebrae slowly lose height and develop bent spine (called kyphosis). Often, osteoporosis is combined with vitamin D deficiency (a condition called osteomalacia) and patients then suffer from severe aches and pains in the back and upper legs. Osteoporosis is also caused by several drugs especially steroids and is associated with several hormone disorders like diabetes and thyroid diseases.
Osteoporosis is widely prevalent. Women are predominantly affected near menopause while men usually suffer much later after 70 years age. Though exact data is not available, 25 million of Indian population may be suffering from osteoporosis.
An understanding of bone physiology is important to understand preventive and treatment strategies. The peak bone mass is reached by the third decade of life. Though calcium and vitamin D intake and regular exercise in childhood and adolescent age play a pivotal role, the bone mass also depends upon genetics and ethnicity. The bones are in a constant dynamic balance state of bone formation and resorption throughout life, and this process is more so in the spine vertebrae. Osteoporosis is cause by increased resorption or infrequently less bone formation.
‘Prevention is better than cure’ and this thought is exemplified in osteoporosis.

Important preventive measures are:

1. Exercise: Weight bearing exercises increase bone mineral density (BMD). It has synergistic effects with other modalities.
2. Lifestyle: Major lifestyle issues associated with low BMD are alcohol, tobacco, inactivity and low weight. These issues have a bearing on other aspects of health too.
3. Diet: High calcium intake leads to better BMD. Milk , dairy products, green leafy vegetable, seeds and fish are good sources of calcium.
4. Drugs: Medications like steroids and high dose thyroid hormone need to be taken only as per requirement as they are associated with low BMD if overdosed.
5. Surroundings: Prevention also involves keeping environment safe like eliminating exposed wires, curtain strings, slippery rugs, tables and providing good light in paths to bathrooms to abate falls.

Recent development in medicine has increased treatment options towards this painful and debilitating disease. These could be divided as nutritional and pharmacological therapies.

Diet and Nutritional Therapies:

1. Diet: Milk and dairy products, cheese, curd, green leafy vegetables, soybean, fish, figs, almonds, tofu, pulses (ragi, rajma, urad, nachani, etc)
2. Calcium: Its importance can never be overestimated. It has been proved that the calcium intake is often deficient in large majority of population. Calcium supplementation is often required as diet is not able to meet the daily demand in menopausal women. There is no difference in quality of different calcium forms but carbonates need to be consumed before meals and citrates can be taken any time. Generally, 500-1000 mg elemental calcium is to be taken daily in 1-2 doses.
3. Vitamin D: This vitamin is required for calcium absorption from the gut and along with calcium causes bone mineralisation. Diet and sunshine are the two main natural sources. Its deficiency is very common. Consuming more than 400-600IU is important.
4. Other nutrients: Vitamin K and Magnesium need to be supplemented in special situations

Pharmacological Therapies:

1. Biphosphonates: These are the most common drugs used for prevention and treatment. These have an inhibitory effect on osteoclasts which are the bone eating (resorption) cells. Several drugs are available. Some can be taken daily or weekly ( alendronate, risedronate (oral)), monthly (ibandronate(oral)) or yearly (zoledronic acid(injectable)). All have similar efficacy.
2. Tereperatide: It is a recombinant parathytroid hormone. It helps in bone formation and thus increases BMD. It needs to be given as subcutaneous injection daily for 18-24 months. Side effects of teriparatide are generally mild and can include muscle pain, weakness, dizziness, headache, and nausea.
3. Calcitonin: It is a polypeptide hormone produced by the thyroid gland. Given in injectable form or as a nasal spray it acts by inhibiting the osteoclasts. Its effect is inferior to biphosphanates and teraperatide.
4. Hormone replacement therapy (HRT): HRT is populary composed of oestrogen and /or progesterone, and is advised for troublesome perimenopausal symptoms of hot flushes. The most important and consistent effect of HRT has been in increasing the BMD as compared to its other utilities. Oestrogen also has heart and bone protective effects. The role of progesterone, another well known female sex hormone required for menses and pregnancy, is controversial. Recent data shows that excess drug use of female sex hormones can actually cause breast and uterine cancer and heart diseases and stroke.
5. Selective oestrogen receptor modulators (SERMs): These drugs have a more specific effect on the bone and are more safe compared to HRT. But they do have side effects.
6. Strontium ranelate: It is a fluoride compound. It is a potent stimulator of bone formation but its effect to increase BMD and reduce osteoporosis is modest and not used popularly in India.

The new medications that we have discussed have greatly helped in tackling this menace but often we face a scenario of patients presenting with osteoporotic fracture as their first feature. Patients can still suffer from a fracture even when they are on regular osteoporosis treatment though chances reduce. A fracture of spine can lead to spinal cord and nerve compressions and neurological complication of paralysis. Management is a difficult process and with limited benefits. These can be considered as Surgical and Non Surgical.
1. Surgical therapy:
The type of surgery is dictated by site of fracture and general condition of patient. Vertebral fractures can be managed by vertebroplasty or kyphoplasty. There is no long term data about them and have now become a subject of debate. Its utility is more in young patients with focal problem. Hip or other fractures can be managed by arthroplasties or joint replacement.
2. Non Surgical:
Tackling acute pain with rest and simple pain killers can make a person comfortable. Chronic pain might need stronger agents like narcotics. Using aids like lumbar belts, walking sticks or walker help in off loading and make ambulation possible. These need to be correct design though to be of optimal benefit or can turn out to be more of problem.

Osteoporosis was seen as a disease with bleak outcome just a few years back but now with better understanding of disease and improved treatment options we can expect to give a patient comfortable and a functional life. Awareness of osteoporosis and proper health education are critical to prevent and treat osteoporosis. One must remember that bone health must be improved in childhood and young age because with increasing age bones don’t really become stronger. Children should be given proper calcium rich diet, exposed to sunshine, maintain proper body weight and exercise regularly.