Osteoporosis

Understanding Osteoporosis

Osteoporosis is a systemic skeletal disease characterized by low bone mass and the deterioration of bone tissue microarchitecture. This leads to increased bone fragility and susceptibility to fractures. Clinically, osteoporosis is diagnosed based on low bone density measurements, though microarchitectural deficiencies and external factors also contribute to bone fragility. Approximately 7.8 million individuals over 50 are affected, with 80% being women. Postmenopausal women particularly face a one in three chance of experiencing an osteoporosis-related fracture, with the incidence of vertebral and hip fractures increasing exponentially with age.

Symptoms

There typically are no symptoms in the early stages of bone loss. But once your bones have been weakened by osteoporosis, you might have signs and symptoms that include:

• Back pain, caused by a broken or collapsed bone in the spine.
• Loss of height over time.
• A stooped posture.
• A bone that breaks much more easily than expected.

When to see a doctor You might want to talk to your health care provider about osteoporosis if you went through early menopause or took corticosteroids for several months at a time, or if either of your parents had hip fractures.

The WHO's 1994 definition of osteoporosis is based on a bone mineral content that is more than 2.5 standard deviations below the mean for a 20-29-year-old woman and can also be applied to men over 50.

Causes Your bones are in a constant state of renewal — new bone is made and old bone is broken down. When you're young, your body makes new bone faster than it breaks down old bone and your bone mass increases. After the early 20s this process slows, and most people reach their peak bone mass by age 30. As people age, bone mass is lost faster than it's created.

How likely you are to develop osteoporosis depends partly on how much bone mass you attained in your youth. Peak bone mass is partly inherited and varies also by ethnic group. The higher your peak bone mass, the more bone you have "in the bank" and the less likely you are to develop osteoporosis as you age.

WHO Classification

The WHO classification is based on the observation that fracture risk increases continuously with decreasing bone density and exponentially at very low values. WHO criteria should therefore be viewed as guidelines that contribute to the confirmation of an "osteoporosis" diagnosis and therapeutic decisions. Ultimately, a combination of history, physical examination, and diagnostic tools is decisive.

Prevention and Treatment

• Normal: T-Score up to -1 SD (up to 10% loss of bone density)
• Osteopenia: T-Score between -1 and -2.5 SD (10-25% loss of bone density)
• Osteoporosis: T-Score < -2.5 SD (more than 25% loss of bone density)
• Manifest Osteoporosis: Osteoporosis with fracture
• Diagnosing Osteoporosis: Diagnosis is established through a combination of patient history, clinical findings, basic laboratory tests, and diagnostic imaging.

Recommended Basic Diagnostic Approach:

For Who:

• Women aged 50-60 and men 60-70 with certain risk factors or findings.
• Women aged 60-70 and men 70-80 with additional risk factors.
• Women over 70 and men over 80, if therapeutic consequences are to be drawn.

Physical Examination Particularly in patients with manifest osteoporosis and related fractures, such as vertebral fractures, physical examination may reveal acute and chronic pain, as well as specific findings like contusions or scars from falls, and a reduced rib-to-pelvis distance.

Osteological Laboratory Screening It’s advised to take fasting morning samples for a comprehensive panel including BSR/CRP, differential blood count, calcium, phosphate, protein electrophoresis, alkaline phosphatase, creatinine, TSH basal, gamma-GT, 25-(OH)-D, intact PTH in hypo- or hypercalcemia, and bone turnover markers like β-CrossLaps (CTx) and Procollagen Type 1 N Propeptide (P1NP).

Instrumental Diagnostics

- Osteodensitometry: The reduction in bone density is a strong, independent risk factor for osteoporosis-related fractures. Bone density measurements, particularly dual-energy x-ray absorptiometry (DXA), provide critical risk assessment information. - Quantitative Ultrasound (QUS): This radiation-free method measures ultrasound transmission velocities and/or broadband ultrasound attenuation at the heel or phalanges. Absolute Fracture Risk and Therapy Threshold

The goal of osteoporosis diagnostics is to provide a precise individual risk assessment for osteoporosis-related fractures. The WHO defined osteoporosis in 1994 solely based on bone density, thus focusing on a single risk factor.

Clinical Risk Factors Factors associated with a significantly increased fracture risk depending on age and gender include underweight (BMI < 20), immobility, smoking, multiple falls, malabsorption, primary hyperparathyroidism, early menopause, Cushing's syndrome, rheumatoid arthritis, ankylosing spondylitis, type I diabetes (below 70 years), type II diabetes, inflammatory bowel disease, and basal TSH < 0.3mU/I²⁾, among others.

Therapy: General Osteoporosis and Fracture Prevention

• Nutrition and lifestyle recommendations include no smoking, limited alcohol consumption, daily outdoor time, adequate calcium and vitamin D3 intake, and regular physical activities to improve muscle strength and coordination.
• Measures for fall prevention and medication review, considering the individual benefits and risks of medications that may contribute to falls or osteoporosis.

Therapy Concepts

Implementation of baseline measures.

• For fractures: Pain therapy, functional improvement, possible vertebroplasty or kyphoplasty if resistant to pain therapy for more than 3 months.
• Further investigation and treatment of secondary causes if clinical and/or laboratory evidence suggests a high fracture risk.
• Potential medication