Osteoporosis – colloquially called bone loss – (synonyms: Senile osteoporosis; bone atrophy; bone decalcification; bone demineralization; osteoporosis;ICD-10-GM M80.-: Osteoporosis with pathological fracture; ICD-10-GM M81.-: Osteoporosis without pathological fracture; ICD-10-GM M82.-: Osteoporosis in diseases classified elsewhere) is an age-associated systemic skeletal disease. Osteoporosis is a systemic skeletal disease associated with aging, resulting in a progressive decrease in bone mass and bone quality, which significantly increases the risk of fractures.
World Health Organization (WHO) osteoporosis definition based on osteodensitometry using the DEXA method:
- Normal – T value between 0 and -1 standard deviation (SD) below maximum bone mass + no fractures (broken bones).
- Osteopenia – T-value between -1 and -2.5 SD below maximum bone mass + no fractures.
- Osteoporosis – T-value less than -2.5 standard deviation below maximum bone mass + no fractures.
- Manifest osteoporosis – T-value less than -2.5 SD below maximum bone mass + 1-3 osteoporosis-related fractures.
- Advanced osteoporosis – T-value less than -2.5 SD below maximum bone mass + multiple vertebral fractures, often extraspinal fractures (fractures outside the spine).
The threshold of -2.5 standard deviations was chosen by WHO because it correlates reasonably well with the incidence of osteoporotic fractures in women. Whether this threshold also correlates with fracture incidence in men is currently controversial.
The World Health Organization lists osteoporosis among the top 10 common diseases.
Sex Ratio: The female-to-male ratio is 6:1 in 60-70 year olds, which decreases to 2:1 in those over 70.
Frequency peak: Osteoporosis is a disease of older age. One in 4 women and 1 in 17 men older than 50 years have osteoporosis.
The prevalence (disease incidence) is 25% of postmenopausal women (women after menopause) in Germany.
The incidence (frequency of new cases) is for osteoporotic-related nonvertebral (spine-related) fractures:
- Women over 50 years: 19 diseases per 100,000 population.
- Men over 50 years of age: 7.3 diseases per 100,000 inhabitants.
Course and prognosis: more than half of those affected suffer at least one fracture within four years. The following skeletal regions are affected: proximal femur (thigh bone), distal radius (radius), proximal humerus (upper arm bone) and vertebral body. At least 400,000 fractures due to osteoporosis occur each year in Germany. These are mostly femoral neck and vertebral body fractures. In the first 1-2 years after a fracture of the proximal femur (fracture of the femur close to the hip joint), mortality is 20-25% (number of deaths in a given period, based on the number of the population concerned)!
The average life expectancy of patients with osteoporosis is over 15 years in women aged under 75 years and in men aged under 60 years.
