Osteoporosis and Osteoarthritis: What Affects Bone and Joint Health
With age, the bone tissue and joints of the musculoskeletal system change, but the pace and mechanisms of these changes are not uniform. Mineral density declines gradually, while changes in the joints are mostly mechanical and biological in nature; after menopause, bone loss can accelerate. In people of the same age, these changes can vary enormously in scale — from minimal age-related differences to clinically significant disorders.
Osteoporosis and Osteoarthritis: What's the Difference
Osteoporosis and osteoarthritis are often mentioned together, but biologically they are different processes. Osteoporosis is linked to a decline in bone strength and an increased risk of fractures. Osteoarthritis involves pathological changes in the joint that affect not only the cartilage but also the subchondral bone (the bone tissue directly beneath the articular cartilage) and other joint structures (McDonald et al., Nat Genet, 2022).
Osteoporosis and osteoarthritis have different mechanisms of development and different risk factors. A person can have low bone mineral density with entirely healthy joints. At the same time, pronounced joint changes can appear with normal bone density. In other words, one condition is not a sign or a cause of the other.
Normal joint mobility does not rule out bone loss, just as osteoarthritis is not inevitable with age. The risk of osteoporosis and osteoarthritis builds up long before symptoms appear. Factors that influence this risk include age, hormonal status, physical activity, body weight, nutrition, previous injuries, past or existing illnesses, and medication use. Genetic factors also influence the risk, and information about them can be obtained long before any joint changes occur.
Why Bone Strength Loss Stays Unnoticed for So Long
A decline in bone mineral density does not itself cause pain, so a person may go years without noticing the change. Throughout life, bones are remodeled — old tissue is resorbed (that is, it undergoes a natural breakdown process), and new tissue forms in its place. If, at a young age, these processes work mainly to maintain or increase bone mass, then with age the balance can gradually shift toward a loss of bone mineral density.
A fracture after a fall from standing height, or another minor injury that would not normally damage healthy bone, can be the first sign of reduced bone strength.
Assessing osteoporosis is not based on symptoms alone. An objective measurement is needed — densitometry (DXA) determines bone mineral density. According to US Preventive Services Task Force recommendations, screening is recommended for all women aged 65 and older. For younger women, particularly those who are postmenopausal, the decision to order such testing depends on existing risk factors and clinical judgment (US Preventive Services Task Force, Screening for Osteoporosis to Prevent Fractures, 2025). Age alone is not a sufficient reason either to screen or to defer screening.
How Age and Menopause Affect Bone Tissue
One of the regulators of bone remodeling is estrogen: it affects the activity of cells (osteoclasts) responsible for bone resorption and helps maintain the balance between breakdown and formation. After menopause, estrogen levels decline, which speeds up bone remodeling. In the first years after menopause, bone loss can be especially rapid (Lee et al., Int. J. Mol. Sci., 2026).
Besides hormonal changes, bone health is also shaped by peak bone mass formed at a young age, physical activity, body weight, calcium and vitamin D intake and metabolism, smoking and alcohol use, medication use, coexisting illnesses, and family history of fractures (Lee et al., Int. J. Mol. Sci., 2026). Every woman enters the postmenopausal period with her own reserve of bone strength.
Osteoarthritis Is a Disease of the Whole Joint, Not Just the Cartilage
Osteoarthritis is often described as the result of gradual wear of the articular cartilage. This model is convenient for everyday explanation, but biologically it is overly simplified: osteoarthritis is a disease of the entire joint, which is made up of the articular cartilage, the subchondral bone, the synovial membrane, the ligaments, and other structures. Each of these structures undergoes its own changes — mechanical, cellular, and signaling. So the mere fact of a joint aging does not by itself mean osteoarthritis will inevitably develop (NICE, Osteoarthritis in over 16s: diagnosis and management, 2022).
The risk of osteoarthritis is influenced by two groups of factors: mechanical (injuries, load on the joint, body weight) and individual, including age, anatomical features, and genetic predisposition.
What Determines an Individual's Risk of Osteoporosis and Osteoarthritis
An individual's risk of osteoporosis and osteoarthritis depends on a combination of factors: genetic variants affect the biological characteristics of bone tissue and the joint, hormonal status changes the environment of bone remodeling, previous injuries determine the mechanical context for a specific joint, and nutrition, body weight, activity level, and coexisting illnesses add further layers of influence. None of these works in isolation.
This multiplicity also applies to genetics itself: there is no single “osteoporosis gene” or “arthrosis gene.” Both osteoporosis and osteoarthritis have a polygenic nature — the risk of these conditions is influenced by numerous genetic variants, each usually making a small contribution, together with environmental and lifestyle factors.
What's Known About the Genetic Factors of Bone and Joint Health
A study that pooled data from more than 400,000 people identified over 500 loci linked to bone mineral density measures (Morris et al., Nat Genet, 2019). Among the genes identified are LRP5 (LDL receptor related protein 5), WNT16 (Wnt family member 16), and COL1A1 (collagen type I alpha 1 chain). These cover different aspects of bone biology — from signaling pathways involved in bone formation to the structure of the collagen matrix.
Another gene that researchers are actively studying in connection with bone mineral density is VDR (vitamin D receptor) (Lee et al., Int. J. Mol. Sci., 2026). Its variants are linked to cell sensitivity to vitamin D as well as to bone density. It's important to remember that polymorphisms in the VDR gene do not determine vitamin D deficiency: the receptor gene and blood vitamin D concentration are two different things, and it's a blood test that shows the actual level of the nutrient in the body.
For more, see the article Vitamin D: Why There's No One-Size-Fits-All Dose.
Osteoarthritis has its own separate genetic architecture, which is also polygenic. A multi-ancestry analysis confirmed the link between a number of known loci and osteoarthritis and identified new ones (McDonald et al., Nat Genet, 2022). Among them are variants near GDF5 (growth differentiation factor 5), a gene involved in the development of musculoskeletal tissues.
Жодна з цих генетичних асоціацій не означає діагноз і не визначає індивідуальний сценарій — вона показує, що ознака має спадковий компонент.
How to Assess Risk and Genetic Predisposition to Osteoporosis and Osteoarthritis
No single indicator gives a complete picture of the musculoskeletal system's condition and overall health: clinical factors, hormonal status, nutrition, lifestyle, and, when needed, densitometry and laboratory results complement one another. Assessing the genetic component is also useful here, since it forms a stable context that doesn't depend on current physical activity level, body weight, or hormonal status. Information about post-workout recovery speed is useful for understanding an individual's response to training load, while data on vitamin D and magnesium, calcium, and phosphorus absorption makes it possible to analyze the biological features of nutrient metabolism. While lab tests reflect the body's current state and clinical assessment captures risks and symptoms, genetic data show a stable hereditary component that remains relevant throughout life.
Genetic variants linked to bone mineral density and to characteristics associated with osteoarthritis can be analyzed as part of the test in the “Musculoskeletal System, Injuries and Recovery” category, or within the full genetic panel covering more than 1,000 markers — all options in the Apixmed Prism catalog.
When to Discuss Risk Assessment With a Doctor
No symptoms doesn't mean no risk. It's worth seeing a doctor if you have:
- a fracture from a minor injury that wouldn't normally damage healthy bone,
- a family history of osteoporosis or fractures,
- a postmenopausal period combined with other risk factors,
- long-term use of medications that can affect bone tissue,
- a significant decline in physical function,
- recurring or progressive pain, stiffness, or limited joint mobility.
In such situations, the doctor determines exactly what data is needed for a proper assessment.
Osteoporosis and osteoarthritis can develop unnoticed long before the symptoms that prompt someone to seek medical care appear. Factors that shape individual risk include age, hormonal status, lifestyle, and genetic characteristics that don't change over a lifetime. Prevention means assessing these factors today, rather than waiting for chronic pain or a fracture to occur.
See the Apixmed Prism genetic test catalog.
Frequently Asked Questions About Osteoporosis and Osteoarthritis
How does osteoporosis differ from osteopenia?
Osteopenia is reduced bone mineral density that, based on DXA results, does not reach the diagnostic threshold for osteoporosis. Both conditions are classified using different T-score values (a measure reflecting the deviation of bone density from normal) from the same scan.
Does a genetic predisposition to low mineral density mean osteoporosis will develop?
No. It's an increased likelihood of low mineral density relative to a reference population: the eventual outcome also depends on age, hormonal status, and lifestyle.
Does sport protect against osteoarthritis?
Physical activity is important for the function of the musculoskeletal system, but the risk of osteoarthritis is shaped by a combination of factors: previous injuries, load, body weight, age, and genetic predisposition.
At what age should you get a densitometry scan?
According to the 2025 USPSTF recommendations, screening is recommended for women aged 65 and older; for postmenopausal women under 65, the decision depends on risk factors and clinical judgment.
The results of a genetic test are not a diagnosis and do not replace a doctor's consultation. The Apixmed Prism report provides genetic context that complements the results of examinations and helps in making decisions together with your doctor.
Sources
1. US Preventive Services Task Force; Nicholson, W. K., Silverstein, M., Wong, J. B., et al. (2025). Screening for Osteoporosis to Prevent Fractures: US Preventive Services Task Force Recommendation Statement. JAMA, 333(6), 498–508. https://doi.org/10.1001/jama.2024.27154
2. Morris, J. A., Kemp, J. P., et al. (2019). An atlas of genetic influences on osteoporosis in humans and mice. Nature Genetics, 51(2), 258–266. https://doi.org/10.1038/s41588-018-0302-x
2a. Author Correction: An atlas of genetic influences on osteoporosis in humans and mice. (2019). Nature Genetics, 51(5), 920. https://doi.org/10.1038/s41588-019-0415-x
3. McDonald, M.-L. N., Lakshman Kumar, P., Srinivasasainagendra, V., et al. (2022). Novel genetic loci associated with osteoarthritis in multi-ancestry analyses in the Million Veteran Program and UK Biobank. Nature Genetics, 54(12), 1816–1826. https://doi.org/10.1038/s41588-022-01221-w
4. National Institute for Health and Care Excellence (NICE). (2022). Osteoarthritis in over 16s: diagnosis and management (NG226). https://www.nice.org.uk/guidance/ng226
5. Lee, K. I.-R., Chen, J.-H., Chen, K.-H. (2026). Osteoporosis After Menopause and After Drug Therapy: The Molecular Mechanism of Bone Loss and Its Treatment. Int. J. Mol. Sci., 27(2), 641. https://doi.org/10.3390/ijms27020641
