15 March 2019 Osteoporosis is characterised by increased skeletal porosity and decreased bone mass. Approximately 30% of post-menopausal women in Europe have osteoporosis and of these at least 40% will develop osteoporotic fractures. The skeleton is a living tissue, with very active cells (osteoblasts, osteoclasts and osteocytes) that renew constantly throughout its life — it is calculated that an adult skeleton completely renews itself every 10 years. The 206 bones that make up the human skeleton are fully developed by the age of 20, and peak bone mass is reached between the ages of 16 and 25: 60% to 80% of this peak is determined by genetic factors; 20% to 40% is determined by the person’s environment. What are the main causes of osteoporosis and how can it be prevented? The loss of bone mass is a consequence of ageing ; it starts at around 40-45 years of age, speeds up during menopause and continues throughout the life of the individual. Men attain a peak bone mass that is higher than that of women and lose less over the course of their lifetime , so only a small percentage of (very) elderly men will have osteoporosis. On the other hand, about 30% of a woman’-s bone mass can be lost in the 10 years after the menopause because the oestrogen deficit that characterises this phase of life leads to greater activity of osteoclasts (which reabsorb bone) in comparison with osteoblasts. Therefore, the loss of bone mass as a consequence of ageing can be explained by the following factors: Decreased absorption of calcium in the gut; Changes in vitamin D metabolism; Some degree of renal failure; A more sedentary lifestyle. How can peak bone mass be increased? Various studies have shown that maximising peak bone mass is an important strategy in the prevention of osteoporosis. If peak bone mass can be increased by 10% , the following results can be obtained: A 13-year delay in the onset of osteoporosis; A 50% reduction in the risk of fracture after menopause. To increase peak bone mass , the in utero foetus should receive sufficient amounts of calcium . Therefore, if pregnant women do not consume milk or dairy products and calcium-rich foods, they should be prescribed with calcium supplements . Later, children and adolescents, in addition to consuming calcium-rich foods daily and having adequate protein intake, should undertake regular physical activity in order to stimulate osteoblasts (bone-forming agents). Does osteoporosis have symptoms? Osteoporosis does not have any symptoms ; or rather, when they manifest, it is too late to do anything about it because there will have been a fracture, often without any trauma. It is therefore very important to check whether you are at risk of osteoporosis and, to this end, diagnostic tests will be necessary. How is osteoporosis diagnosed? Where there are risk factors for osteoporosis, at age 50 , if not earlier, a bone density test of the lumbar spine and femur should be requested; this will classify the patient as being: Normal - if bone mineral density (BMD) is identical to the norm for a young adult; Osteopenia - if there are between 1 and 2.5 standard deviations below the norm for a young adult; Osteoporosis - if the standard deviation is greater than 2.5. Is there any treatment for osteoporosis? Patients with osteopenia are advised to modify their lifestyle . They should: Eat food that is rich in calcium and vitamin D or take supplements - calcium 1200 mg/day, and vitamin D 800 IU/day; Engage in regular physical activity - walking and gym; Stop smoking; Cut down on alcohol consumption as these substances are toxic for osteoblasts. Post-menopausal women should start taking hormone therapy to compensate for oestrogen deficiency (as long as there are no contraindications). Osteoporosis greatly increases the risk of hip, spine and wrist fractures, and so drug therapy will be necessary ; this will be tailored to the patient’s individual needs at the relevant time and may be discussed during the gynaecology consultation. Finally, osteoporotic fractures lead to a higher annual incidence of: Myocardial infarction; Stroke; Breast cancer. Not only do they significantly reduce the quality of life of those who suffer them, but they also increase the risk of mortality - 20% of women who break their hip die one year after fracture. With increased longevity, it is estimated that there will be a significant increase in such fractures in years to come. This article was written with the support of physicians and other clinical professionals from the Hospital da Luz network. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
