Given the increase in life expectancy, the consequences of osteoporosis will continue to increase over the next few years. At the European level, the number of people with osteoporosis is expected to increase by 23% and the annual number of osteoporosis-related fractures by 28%. 14/11/2018 3:41PM
THE GOAL OF OSTEOPOROSIS TREATMENT IS TO PREVENT FRACTURES AND ASSOCIATED MORBIDITY AND MORTALITY. PHARMACOLOGICAL AND NON-PHARMACOLOGICAL TREATMENTS ARE COMPLEMENTARY FOR COMPREHENSIVE MANAGEMENT, WHICH SHOULD GIVE PRIORITY TO IDENTIFYING MODIFIABLE RISK FACTORS.
Even if osteoporosis is established, it is important to maintain or adopt healthy lifestyle measures to limit bone loss and prevent fractures:
- adequate calcium and vitamin D intake
- physical activity adapted to the state of health but regular; – stopping
- limiting alcohol consumption
- in the elderly, measures must be taken to prevent falls: improvement of vision, home layout (remove carpets, obstacles, have good lighting), reduction or even elimination of certain drugs (hypnotics, sedatives…), walking aids (canes…), adapt clothing (shoes with non-slip soles…).
All the treatments associated with calcium and vitamin D supplements have demonstrated their effectiveness in reducing the risk of vertebral fractures.
Some of them are also associated with a significant reduction in the risk of non-vertebral fractures, particularly hip fractures.
A classic distinction is made between anti-resorber drugs and osteoformers:
Bisphosphonates are powerful inhibitors of osteoclasts, and therefore of bone resorption. They inhibit an enzyme, FPPS (farnesyl pyrophosphate synthase), which stabilizes GTPases essential to their function. Blocking the FPPS thus promotes the apoptosis of osteoclasts. The bioavailability of bisphosphonates after oral administration is extremely low (of the order of one percent) and practically nil when taken with food, so it is essential to take them on an empty stomach. The most commonly prescribed oral molecules are administered once a week. The alternative, in particular to eliminate the problem of non-adherence to treatment, is to use the intravenous route. Many osteodensitometric studies have demonstrated the efficacy of bisphosphonates on trabecular and cortical BMD, with a gain of 5 to 10% in 3 years, often with a plateau effect. More importantly, bisphosphonates clearly reduce the risk of fracture (by about 50%) and this effect is surprisingly rapid. The differential between a modest effect on BMD and a magisterial effect on fractures suggests that the beneficial effect of bisphosphonates is also qualitative, beyond a quantitative gain.
IN PRACTICE, A BISPHOSPHONATE WILL ALWAYS BE PRESCRIBED WITH CALCIUM SALT AND VITAMIN D3 SUPPLEMENTS, USUALLY FOR A PERIOD OF 5 YEARS (MAXIMUM 10). A PERSISTENT EFFECT IS OFTEN OBSERVED. THE EFFECT ON REMODELLING CAN BE RAPIDLY ASSESSED AFTER 3 MONTHS OF TREATMENT.
Our advice: The importance of ingesting the oral forms with sufficient water cannot be overemphasized. Avoid lying down after taking them, as this can irritate the oesophagus. The risk of osteonecrosis of the mandible is truly exceptional but considerably damages the reputation of bisphosphonates. Prevention is essential here, by advising adequate dental care (and corresponding extractions if necessary) before starting treatment.
Denosumab is a monoclonal antibody directed against RANKL. It is administered subcutaneously every 6 months and strongly blocks bone resorption. The BMD gain is generally greater than with bisphosphonates, and is maintained for a longer period of time. Conversely, there are no persistence effects, which could be an advantage over bisphosphonates that remain in bone tissue for a very long time. Denosumab is reimbursed by social security only after failure of a bisphosphonate (or side effects), unless there is a primary contraindication, such as a reduction in glomerular filtration. Surprisingly, based on the role of RANK/RANKL in the functioning of the immune system, initial fears of observing many infectious side effects have not proven to be well-founded. The theoretical risk of osteonecrosis of the mandible has not been confirmed by clinical studies.
Osteoformative treatments are a matter for specialized medicine. Romosozumab could change our therapeutic habits. The treatment is truly anabolic as it stimulates the recruitment of new bone units. Parathormone analogues are administered subcutaneously on a daily basis. They allow a gain in BMD. Bisphosphonates are likely to be required to maintain it.
Diets without dairy products
In the case of lactose intolerance, it has been shown that osteoporosis is much more common, and in the case of lactase deficiency, there is an increased risk of fracture. In children, the suppression of milk leads to a decrease in bone mineral density and would triple the incidence of fractures. In case of diets without dairy products, calcium and vitamin D supplementation should be carried out.
What about the dispensary?
Several modifiable or non-modifiable risk factors (age, sex, etc.) have a direct influence on bone biology and lead to a decrease in bone mineral density. In terms of prevention, the pharmacist will make sure that risk factors are made aware of, identified and possibly corrected. The majority of modifiable risk factors are linked to poor lifestyle habits (alcoholism, smoking, lack of physical activity, etc.). The decrease in bone mineral density can also be the consequence of certain diseases or an adverse effect of certain drugs (Table 1). Adherence during the first year of treatment is very low (about 51%), and at this level the risk of fractures is the same as for an untreated patient. Awareness of patients by pharmacists on compliance with prescriptions is therefore a public health issue. Adherence and persistence to treatment can be encouraged by explaining to the patient his pathology and the role of prescribed medicines. The problem of adherence to daily calcium and/or vitamin D intake very often arises, whether in prevention or treatment, in association with anti-osteoporotic drugs. Specialities combining calcium and vitamin D, provided that the dosage is adapted, promote adherence.