Osteopenia

What is Osteopenia?

Osteopenia is a term used to describe the condition where a person’s bone density is lower than the normal range, but not low enough to be identified as osteoporosis. Bone density refers to the amount of mineral substance in your bones, which can be measured using a special type of x-ray known as Dual-Energy X-ray Absorptiometry (DXA) scans. According to the World Health Organization (WHO), you may get diagnosed with osteopenia if your test results, often referred to as a ‘t-score’, range between -1 to -2.5. If your t-score drops below -2.5, you would be diagnosed with osteoporosis.

Decreasing bone density indicates that there might be a problem with the structure of your bones at a microscopic level. Both osteopenia and osteoporosis are disorders related to the quantity of mineral in your bones, rather than the quality of the mineral itself.

What Causes Osteopenia?

From the time we are born up to adulthood, our bodies continuously increase the amount of minerals in our bones – this process changes based on our age and sex. For example, as we reach puberty, our bodies start storing minerals in the bones at the highest rate, shortly after we hit our maximum height during our teenage years. This process continues at a high rate for about four years, and by age 17 in girls and 21 in boys, our bodies have usually stored 95% of the total bone minerals we’ll have as adults. Therefore, by the time we’re in our thirties, we’ve typically reached our peak bone mass.

If we fail to reach this peak bone mass during our younger years, we might start suffering from conditions like osteopenia or osteoporosis, where the bones become weak and can easily break. These conditions can occur even during adolescence or early adulthood. After the age of 30, it’s normal for our bones to gradually lose some of their mineral content over the coming years.

Up to 80% of our ability to store and keep the maximum amount of minerals in our bones is dictated by our genetics. However, other factors that we can control also play a role, such as doing weight-bearing exercises, maintaining good nutrition (like getting enough calcium and vitamin D), optimizing our body weight, and managing our hormones.

As we get older, our bones naturally lose some of their minerals which is the primary cause of osteopenia and osteoporosis. Other factors can speed up this process, including lifestyle habits like drinking alcohol, smoking, living a sedentary lifestyle, or being underweight. White and Asian people are also at a higher risk.

Certain medical conditions can worsen bone loss, for example hyperparathyroidism (overactive parathyroid glands), anorexia, malabsorption syndromes (where nutrients are not properly absorbed by the body), hyperthyroidism (overactive thyroid), chronic kidney failure, hypogonadism (low levels of sex hormones), amenorrhea/oligomenorrhea (irregular or absence of periods), early onset menopause, and any long-term condition resulting in the deficiencies of calcium and/or vitamin D. Certain medications can also contribute to bone loss such as long-term steroid use, valproic acid, proton pump inhibitors, antiepileptic drugs, and chemotherapy drugs.

Risk Factors and Frequency for Osteopenia

Osteopenia, a condition that weakens your bones, currently affects 34 million Americans. As the population ages, it’s estimated that by 2020, more than 47 million Americans will have osteopenia. It’s more common in females, but males may present secondary causes for decreased bone mass. For example, in postmenopausal women, more than half are osteopenic, and an additional 30% are already considered osteoporotic, a more severe form of bone loss.

Worldwide, the situation is also concerning. Asia, for instance, has been found to have the lowest average bone mass. More than 50% of the population in India has osteopenia. The issue is not just the weakening of bones but the subsequent fragility fractures (breaks that occur from falls from standing height or less). These fractures can have serious affects on a patient’s quality of life and put financial stress on the healthcare system.

• Every year, 2 million fragility fractures occur in the United States.
• By 2025, this number is expected to rise to over 3 million.
• Globally, 9 million fragility fractures happen each year.
• The direct medical costs associated with fractures were $19 billion in 2005, and they’re expected to exceed $25 billion by 2025.
• Worse yet, hip fractures are linked with a mortality rate of more than 20% during the first year.

Signs and Symptoms of Osteopenia

Your doctor will take a complete history and check for things that might make you more likely to lose bone. They’ll ask about your habits, like if you smoke or drink alcohol regularly. They’ll also want to know if anyone in your family has had osteoporosis. Your doctor will want to know about any broken bones you’ve had, especially if you were over 40 when you got them or if it was a minor fall.

Your physical exam might not show anything unless the disease is advanced. Doctors usually suggest that women get bone density tests around menopause or by age 65 at the latest. Men usually start these tests at age 70. There aren’t official screening recommendations for men in the United States, and there’s no widespread screening program for osteoporosis yet.

If you’ve had a bone break because of weak bones, it’s really important to see your doctor soon. Even though there’s not a standard way to check up on this, some things that are becoming more common are automatic check-in systems and fracture teams. Right now, only 1-10% of people follow up like they should.

Women who have normal bone density test results don’t need to repeat the test. Research shows that most women with normal results won’t develop osteoporosis. Some doctors might suggest re-testing after starting treatment, but this idea is controversial since follow-up tests usually don’t lead to changes in treatment.

Testing for Osteopenia

The World Health Organization (WHO) regards DXA scans as the most reliable method for measuring bone density. Using a single x-ray beam, DXA scans measure the hardness of specific areas of the body. The results from these scans are very accurate, offer a precision rate of 1% to 2%, and expose the patient to a minimal amount of radiation. The scan usually includes the lower back, hip, and wrist areas.

The DXA scan provides two scores, a t-score and a z-score. The t-score compares your bone density to the average bone density of a healthy 30-year-old woman. If the t-score ranges between -1 and -2.5, it suggests that the bones are less dense than normal, a condition known as osteopenia. A score below -2.5 indicates osteoporosis, a condition where bones are significantly weaker. The z-score, by contrast, compares your bone density to people of the same age group. This score is particularly important in younger patients who may have osteoporosis because of secondary conditions. A z-score below -1.5 suggests the need for further tests.

Typically, doctors will ask for lab tests, checking the levels of various substances in your blood, such as calcium, phosphorus, albumin, liver function tests, and vitamin D, amongst others. For men, they should also check their testosterone levels.

There’s ongoing debate about the usefulness of checking the rate of bone turnover, which can help determine causes of secondary osteoporosis. However, some question the reliability of these tests.

The WHO’s fracture risk assessment tool (FRAX score) can help predict the chance of breaking a hip or having other significant fractures in the next 10 years. The tool answers 12 questions related to the likelihood of future fractures, taking into account age, sex, personal and family medical history, smoking status, and alcohol intake. You can also include results from a previous DXA scan for a more complete assessment.

Doctors especially emphasize the FRAX score for patients with osteopenia. Even though osteoporosis implies a greater risk of fracture, most fractures happen in osteopenic patients, causing a conflict in treatment strategies. The FRAX score helps doctors decide whether more intensive treatment is warranted for osteopenic patients.

If you’re under 50 and at a higher risk of fractures, it’s recommended that you get a DXA scan if you haven’t already for another reason. A 2013 study showed that nearly 2.5 million FRAX score calculations were made across 173 countries, with the highest numbers coming from the USA, UK, Canada, Spain, Japan, France, Belgium, Italy, Switzerland, and Turkey.

Treatment Options for Osteopenia

For patients diagnosed with weakened bones, osteopenia, it’s important to focus on maintaining healthy bone mass levels. Doctors work on this by educating patients about different factors that could disrupt bone health, such as lifestyle choices, environmental factors, and social factors.

Making changes to your lifestyle can help all patients. Drinking alcohol regularly can reduce your bone mass, so it’s helpful to cut back on alcohol consumption. Doctors also strongly recommend that patients stop smoking. Incorporating weight-bearing physical activities and regular exercise into your routine can be very beneficial for your bones. Practices like yoga or tai chi, which reduce stress and improve balance, can also be very beneficial.

Patients should also know how much calcium and vitamin D they should be consuming each day. For adults over 50, the National Osteoporosis Foundation (NOF) advises consuming between 1,200 to 1,500 mg of calcium and between 800 to 1,000 IUs of vitamin D daily.

Preventing falls is also crucial, as the majority of hip and radius fractures are caused by in-home falls. While some studies have mixed findings about the results of exercise programs and physical therapy in reducing falls and subsequent fractures, it’s commonly recommended to combine regular exercise with preventative measures. This could mean removing loose carpets at home, reducing the use of sleep medicine and other tranquilizers, and correcting any visual impairment. This has shown to result in fewer falls, especially in elderly populations.

After being diagnosed with osteopenia, patients should undergo an assessment to determine their risk of future fractures. Treatment with drugs is more controversial in cases of osteopenia as it requires greater numbers to treat effectively compared to osteoporosis. Currently, drug treatment is recommended mainly for those most at risk of significant fractures.

Special attention should be given to tracking and preventing repeat fragility fractures. The risk of re-fracture is highest in the first 1-2 years after an initial fragility fracture, with half of all subsequent fractures occurring within 3-5 years following the first event. Consequently, these patients need a rapid response and follow-up to determine their fracture risk score and obtain a DXA scan to establish base bone mass levels and t-score values.

Special considerations should also be given to vertebral fractures, as they are the most common type of fracture in people over 50, but often go unnoticed because they cause relatively few symptoms. Furthermore, these fractures are associated with significant complications, including a five-fold increase in the risk of subsequent vertebral fractures, regardless of a person’s bone mass at the time of the index fracture.

Medication is typically recommended for individuals with low bone mass and a history of spine or hip fractures. However, treatment recommendations can vary for other fractures. Notably, all postmenopausal women with a history of any fragility fracture are recommended to start treatment by the National Osteoporosis Society (NOS), whereas the National Osteoporosis Foundation (NOF) recommends performing DXA scans on patients sustaining nonvertebral fragility fractures, and the decision to treat with drugs is then based on the patient’s t-score.

There are several drug options available to treat osteopenia, including bisphosphonates, which are the most commonly prescribed medication class. Other medication options include hormone replacement therapy, estrogen-only replacement, salmon calcitonin, selective estrogen receptor modulators, and RANKL inhibitors (Denosumab). Patients on these medications will need to be monitored carefully as the treatment duration varies based on the medication type and stopping some of the medications can lead to rapid bone loss.

Patients on bisphosphonates need to be extra cautious as prolonged use beyond 3-5 years may lead to an increased risk of thigh discomfort, which could be a symptom of an impending abnormal femur fracture. If anyone on those medications experiences mild thigh discomfort, it’s recommended that they stop all weight-bearing activities, get X-rays of the entire femur and hip, discontinue using the bisphosphonate immediately, and seek advice from an orthopedic surgeon.

What else can Osteopenia be?

The following are various conditions that can affect the health of an individual:

• Homocystinuria
• Hyperparathyroidism
• Conditions requiring imaging for osteomalacia (softening of the bones)
• Mastocytosis (excess mast cells in your organs)
• Multiple myeloma (cancer of plasma cells)
• Paget’s disease (bone disorder)
• Scurvy (vitamin C deficiency)
• Sickle cell anaemia (abnormal red blood cells)