Osteoporosis is a condition in which bones become weak and more susceptible to fractures and breaks. Many people are familiar with primary osteoporosis, which is typically caused by increasing age and menopause. However, there are other causes of bone loss that deserve attention. These forms of osteoporosis are termed secondary osteoporosis.
In this article, we’ll discuss causes of secondary osteoporosis, and how treatment for an underlying cause of osteoporosis may differ from treatment for primary osteoporosis.
What is secondary osteoporosis?
According to the International Osteoporosis Foundation, secondary osteoporosis refers to osteoporosis caused by certain medical conditions or medications. Usually, secondary causes of osteoporosis affect the bone remodeling process, or they can prevent optional bone strength from developing if it occurs at a younger age. Unlike primary osteoporosis, secondary causes of osteoporosis can affect individuals of all ages (IOF, 2023).
Primary vs secondary osteoporosis
Primary osteoporosis and secondary osteoporosis differ in their origins and underlying causes. Primary osteoporosis is primarily associated with increasing age and hormonal changes, particularly the decline in estrogen in postmenopausal women. With age, bones naturally lose some density and strength over time.
Secondary osteoporosis, on the other hand, stems from underlying issues such as medical conditions, medications, or lifestyle choices. For example, conditions such as rheumatoid arthritis, celiac disease, elevated calcium levels, or prolonged use of certain medications (eg steroids) can contribute to secondary osteoporosis (Ganesan, 2022).
Understanding this distinction is crucial, as it guides healthcare professionals in tailoring prevention and treatment strategies. Think of primary osteoporosis as more related to the natural aging process, while secondary osteoporosis is usually triggered by an underlying cause or external factors such as medications
If you’ve been diagnosed with a secondary cause of osteoporosis, it’s important to address the underlying cause of your bone loss. Make sure your treatment plan includes modifying those causes to improve bone health outcomes for the future. There are certain causes of secondary osteoporosis that, when treated, can actually improve your bone density. For example, if you are diagnosed with celiac disease and you start a gluten free diet, there can be significant improvement in your bone density. So it’s important to make modifications to your lifestyle, as needed.
What are secondary causes of osteoporosis?
Secondary osteoporosis can be caused by several different factors, including medical conditions and certain medications. Here is a list of some of the most common causes, so you can be aware and discuss whether or not you should be screened for them with your doctor.
Keep in mind that this is a general list, but the degree to which these and other conditions contribute to bone loss can vary from person to person. If you are concerned about how a medical condition or medication may impact your bones, always ask your doctor.
Medical conditions that may cause bone loss
There are a number of different medical conditions that can cause bone loss. These can range from autoimmune conditions to cancer, and even psychological or orthopedic conditions. Here is a comprehensive list, provided by the International Osteoporosis Foundation:
- Autoimmune (Eg: rheumatoid arthritis)
- Chronic obstructive pulmonary disease (COPD) and asthma (often associated with use of oral or inhaled steroids)
- Chronic kidney disease (CKD)
- Digestive and gastrointestinal (includes diseases associated with malabsorption such as celiac, Crohn’s, inflammatory bowel disease, as well as lactose intolerance)
- Endocrine and hormonal (Endocrine disorders such as Cushing’s syndrome, hyperparathyroidism, diabetes; and hypogonadal states, such as Turner syndrome/Kleinfelter syndrome, amenorrhea, Kallmann syndrome)
- Hematologic (eg multiple myeloma)
- Neurological
- Psychophysiological disorders and mental illness (eg: anorexia nervosa, dementia)
- Cancer (eg breast cancer and use of aromatase inhibitors)
- HIV/AIDS
- Some inherited disorders
- Immobility
- Chronic disease in childhood
Medications and substances that cause bone loss
Medications exist for a reason, and can be a critically important part of a treatment plan for acute and chronic medical conditions. However, there are certain medications that, while medically necessary, can have adverse effects on bone. When possible, it is best to minimize/limit long-term use of these medications to prevent this potential side effect.
One example of a medication/substance that may negatively impact your bone health is steroids which when used long-term and in high doses, can cause increased risk for bone loss and fractures (New York Department of Health, 2020). Other examples include aromatase inhibitors, which are often necessary treatments for certain types of breast cancer. This type of medication requires monitoring of bone mineral density and potential treatment with an antiresorptive treatment with initiation to prevent medication-related bone loss.
As part of every medical treatment, it’s always important to weigh the benefits against the risks when deciding what is the best and healthiest choice for you. Your doctor will be able to help you determine the best course of action and appropriate monitoring if on a medication associated with bone loss.
Below is a list of medications that can cause bone loss, from the International Osteoporosis Foundation.
- Androgen/hormone deprivation therapy
- Aromatase inhibitors
- Glucocorticoids* (see below)
- Selective serotonin reuptake inhibitors (SRRIs)
- Thiazolidinediones
- Proton pump inhibitors (PPIs)
- Certain immunosuppressants (calmodulin/calcineurin inhibitors)
- Certain steroid hormones (medroxyprogesterone acetate, luteinizing hormone releasing hormone agonists)
- Certain anticonvulsants, antiepileptic drugs
- Anti-coagulants
- Chemotherapy agents (methotrexate)
- Other medications or chemicals that have been shown to have adverse effects on bone health include: thyroid hormone treatment (in supraphysiologic doses), anxiolytics, sedatives, antidepressants and neuroleptics, certain antipsychotics (lithium), antacids containing aluminium, cigarettes, excessive alcohol use, aluminium and barbiturates
*It’s worth noting that glucocorticoid treatment is the most common cause of secondary osteoporosis (Briot, 2015). Glucocorticoid treatment can interfere with the function of cells responsible for building new bone and stimulates cells that break down bone. If you are taking or have ever taken glucocorticoids for a period of time, speak with your doctor about how it may affect your bone health and risk for bone loss and fracture
What are the potential treatments for secondary osteoporosis?
The first and most effective strategy to treat secondary osteoporosis is to identify the underlying cause and treat the cause. This may mean switching to an alternate medication, weaning off certain medications if possible, and making lifestyle adjustments. For people diagnosed with celiac disease it means starting a gluten free diet. For patients with high calcium due to parathyroid issues, an evaluation for surgery may be indicated.
However, for people who depend on medications to address their potentially more serious conditions, the medication may need to be continued in conjunction with starting an osteoporosis treatment.
Ultimately, as with primary osteoporosis, there are multiple treatment strategies that involve understanding the cause and extent of bone loss, addressing treatable components, and determining the best treatment plan. Of course, involving a combination of exercise, nutrition, medication, and lifestyle changes. Talk to your physician to determine the best work-up and treatment plan for you!