Bone loss and bone fractures are a significant concern during and after many different types of cancer treatment. Appropriate screening, lifestyle modifications and therapies to increase or maintain bone density are essential.
I decided to write this post after I read about a recent study that shocked me. In this study, doctors treated a group of 115 men for prostate cancer using a commonly prescribed hormonal treatment, called androgen deprivation therapy (ADT.) ADT is widely known to reduce bone density in patients on this therapy. This is why it is always recommended that anyone on ADT have their bone density checked before starting treatment and every year thereafter. So…how many men were actually tested..ZERO!! That is appalling.
So, it’s time to go back to school for those doctors and time to inform anyone who might benefit from learning about what can be done to reduce the risk of losing bone density and potentially developing a bone fracture. If I can save one person from developing a broken hip, my mission is accomplished.
Who Is At The Greatest Risk Of Bone Loss and Bone Fractures?
- Women who have undergone menopause due to chemotherapy
Removal of the ovaries or testicles
- Patients receiving hormonal therapies for cancer (i.e. anti-estrogen and anti-androgen therapies, etc.)
- Patients with inadequate calcium intake
- Patients with vitamin D deficiency
- Patients who do not get enough exercise
- Patients who smoke
- Patients who drink too much alcohol
- Patients with a family history of hip fractures
- Patients who use proton pump inhibitors, anticoagulants, and certain antidepressants
- …and numerous other medical conditions
Did you know that even before taking these bone depleting drugs, studies indicate that our lifetime risk of developing a fracture is 40% in women and 13% for men? So, this is a real risk if you then add a bone depleting therapy to the mix.
Are you taking hormonal therapy for breast or prostate cancer?
The longer you are on hormonal therapies for breast and prostate cancer the greater your risk of developing osteoporosis and bone fractures. Not only are fractures painful and cause a tremendous impact on quality of life, but fractures have been shown to increase your risk of dying prematurely by 20%!
Loss of bone mineral density (BMD) occurs at a much higher rate while undergoing hormonal therapies for cancer. Studies show that significant bone loss can already be detected as soon as 6 months after starting hormonal therapy.
- men (not on therapy): lose 0.5% of their lumbar spine BMD each year
- men (on hormonal androgen deprivation therapy for prostate cancer): lose 4-5% of their lumbar spine BMD each year
- postmenopausal women (not on therapy): lose 1-2% of their lumbar spine BMD each year
- women (on aromatase inhibitor therapy for breast cancer): lose 2-3% of their lumbar spine BMD each year (this goes up to 7% if they are also receiving a gonadotropin-releasing hormone agonist)
- women (who develop menopause from chemotherapy): lose 8% of their lumbar spine BMD each year!!
What Is A BMD Test?
The most common BMD test is called a DEXA scan (dual energy x-ray absorptiometry). Typically, a DEXA scan measures your bone density at the hip or spine, which is where most osteoporosis-related fractures occur.
You lie on your back (for 10-15 minutes) on the DEXA scan table while a detector passes over your body. The DEXA scan uses a very low level of radiation (1/10th the amount you get with a chest x-ray) to measure bone density.
What Is A “T-Score”?
DEXA scan results are reported as T-scores. A lower T-score correlates with a lower bone density.
- A T-score of -1.0 or above is normal.
- A T-score between -1.0 and -2.5 indicates low bone density, or osteopenia.
- A T-score of -2.5 or below is an indication of significant osteoporosis.
You may also be given a “Z-score”, which compares your bone density to what is expected for someone of your age, gender, weight, ethnicity, and race.
Who Should Get A BMD Test And How Often Should It Be Done?
Basically, anyone who starts a drug that depletes bone density needs BMD testing:
- A BMD test should be done at baseline (before therapy) and then every 12 months to monitor for further bone loss.
However, even if you are not taking a drug that depletes your bone density, you may still be at risk of osteopenia, osteoporosis and bone fractures (see the recommendations by the National Osteoporosis Foundation, below.)
The National Osteoporosis Foundation and the World Health Organization recommend that individuals who are at “high-risk” of developing a osteoporotic fracture within 10-years should undergo BMD testing every 24 months (or every 12 months if there was a significant loss of bone density at the previous BMD test.)
Estimate your risk of developing a fracture within the next 10-years by using the Fracture Risk Assessment Tool (also known as “FRAX“.)
“High-Risk” of fracture is defined as having a 10-year FRAX risk of 3% or higher for hip fractures and more than 20% for all major fractures.
- “High risk” FRAX score individuals should undergo BMD testing at baseline and every 24 months (or every 12 months if there was a significant loss in BMD at the previous BMD test)
To check out my own FRAX risk, I plugged in my age, date of birth, height and weight (there is an easy to use converter tool that will convert pounds (to kg) and inches (to cm) and other risk factors. My estimated 10-year risk of a major osteoporotic fracture is 1.8% and hip fracture 0.1%.
What Can You Do To Decrease Your Risk Of Osteoporosis & Fractures?
Everyone should aim for at least 30 minutes of moderate physical activity 5-to-7 days per week. This should include a mix of aerobic and weight bearing exercises. Research indicates that the best exercise for your bones is the weight-bearing kind, which forces you to work against gravity (i.e. weight training, walking, hiking, jogging, climbing stairs, tennis, and dancing.) Examples of exercises that are not weight-bearing include swimming and bicycling. Although these activities help build and maintain strong muscles and have cardiovascular benefits, their effects on bone loss are minimal.
Avoid smoking. Tobacco use reduces bone density.
Limit alcohol intake. Drinking alcohol is associated with lower bone density. The National Osteoporosis Foundation recommends limiting alcohol intake to less than 2-3 drinks per day. Although recent studies suggest that drinking even 1-drink per day can increase your risk of cancer…so, I’ll leave this up to you.
Limit your coffee consumption – Drinking more than two cups a day may contribute to accelerated bone loss (caffeine increases calcium loss.) I’m sorry, but I’m going to have to ignore this…I need my coffee.
Get enough calcium:
Most experts agree that calcium is important in maintaining bone density (although calcium supplementation is an area of controversy.) As with all nutrients, we strongly recommend that you try to obtain as much of your daily calcium requirements (see table to right) from food first, and only use supplements to make up for any shortfall. That said, the average dietary intakes of calcium in the U.S. are well below the recommended daily allowance adults, so supplementation is often necessary. Taking more calcium than the daily recommended amount has not been shown to be beneficial…and, in fact, can be harmful.
- Does calcium supplementation increase your risk of cardiovascular disease? Not according to the experts at the Linus Pauling Institute.
To optimize absorption divide your calcium doses (take no more than 600 mg at one time.) Take your calcium supplements with food, as eating food produces stomach acid which helps your body absorb most calcium supplements. The one exception to the rule is calcium citrate, which can absorb well when taken with or without food. Read the product label carefully to determine the amount of elemental calcium, which is the actual amount of calcium in the supplement, as well as how many doses or pills to take. When reading the label, pay close attention to the “amount per serving” and “serving size.”
Get enough Vitamin D: Less controversial (than calcium supplementation) is the beneficial activity of vitamin D (and vitamin D supplementation) in helping to maintain bone density. Vitamin D is involved in numerous bodily functions (i.e. increasing calcium absorption from the intestines, maintaining bone density, reducing systemic inflammation, strengthening the immune system, cell differentiation, etc.) Vitamin D deficiency is also associated with an increased risk of numerous cancer types (although the U.S. NIH’s Office of Dietary Supplements does not agree.)
There are two forms of vitamin D: vitamin D2 and vitamin D3. Studies indicate that vitamin D3 is more effective in raising serum vitamin D (“25 hydroxy vitamin D”, or “25(OH) D”) levels and maintaining those levels for a longer time.
Most adults (70-95%) are deficient in vitamin D, so it is very important to have your blood levels 25(OH)D tested.
What is the optimum 25(OH) D level?
This depends on which guideline or recommendation you read. The reason for the variation is that no one knows the optimum level.
The current ranges for “normal” are 10 to 55 ng/ml (25 to 137 nmol/L). As one of my favorite TV personality physicians and book author writes, “These are fine if you want to prevent rickets — but NOT for optimal health. In that case, the range should be 40 to 65 ng/ml (100 to 160 nmol/L).”
The National Osteoporosis Foundation states that for bone health, your serum level of 25(OH) D should be at least 30 ng/mL (75 nmol/mL).
In this case, I’ll take my chances and follow the less conservative recommendations of the TV personality and book author.
If your level of 25(OH) D is below 30 ng/mL, you will likely need to take a vitamin D3 supplement. There are many ways to supplement with vitamin D3, but you should first discuss this with your physician. I often recommend to patients to take 5,000 IU of vitamin D3 per day and then recheck their 25(OH) D level in 3 months. Be patient. It can take up to 6-10 months to “fill up the tank” for vitamin D if you started off deficient. For maintenance, take 2,000 to 4,000 IU a day of vitamin D3. Some people may need higher doses over the long run to maintain optimal levels.
The graphic (below) indicates the minimum daily requirements from all sources of vitamin D (sunlight, food and supplements.) However, as mentioned above, you will likely need to take supplemental vitamin D3 to reach an optimum 25(OH) D level.
**The Linus Pauling Institute recommends daily supplementation with 2,000 IU of vitamin D3 for adults 50 and older, because aging is associated with a reduced capacity to synthesize vitamin D in the skin upon sun exposure.
There are three ways to get vitamin D: sunlight, food and supplements. Our skin makes vitamin D from the ultra-violet light (UVB rays) in sunlight. The amount of vitamin D your skin makes depends on time of day, season, latitude, skin pigmentation and other factors. Depending on where you live, vitamin D production may decrease or be completely absent during the winter. If you are trying to prevent skin cancer by covering up with clothes and sunscreen, you will significantly reduce your skin’s ability to make vitamin D (i.e. wearing an SPF (sun protection factor) sunscreen of 8 reduces the production of vitamin D by 95%.) Vitamin D is naturally available in only a few foods, including some fatty fish (mackerel, salmon, sardines), fish liver oils, and eggs from hens that have been fed vitamin D. Vitamin D is also added to milk and to some brands of other dairy products, orange juice, soymilk and cereals.
What other vitamins and minerals may help to maintain your bone density?
…The reason for saying ‘may help’ is because the data is conflicting. Some reports say these vitamins or minerals are associated with less risk of osteoporosis, while others refute the same claims.
Vitamin K: The recommended daily amount to reduce the risk of bone fractures is 250 mcg/day. (Read more about vitamin K in our recent post on blood clotting) That said, there is inconclusive evidence that vitamin K supplementation improves BMD or reduces the risk of osteoporotic fracture.
Magnesium: The recommended daily amount is 420 mg/day for men over 30 years of age and 320 mg/day for women over 30 years of age. If you are 65 or older, avoid taking more than 350 mg/day of supplemental magnesium without medical consultation (as the kidneys don’t function as well as we age, and we have a harder time excreting magnesium.)
Vitamin C: The recommended daily amount is 400 mg daily. Vitamin C is essential for bone matrix quality, however the efficacy of vitamin C supplementation on BMD and fracture risk is not clearly established. (Read more about the potential role of vitamin C and cancer prevention and therapy on our recent blog post)
Many other nutrients may also be involved in bone health.
**WARNING: As always, talk with your healthcare provider or pharmacist about possible interactions between prescription or over-the-counter medications and supplements.
New research confirms that standing on a vibration device (such as Juvent) for 10 minutes, twice per day, significantly increases bone density and reduces bone loss. This non-toxic device is a far safer than any osteoporosis drug, and is similarly effective.
How Do You Manage Low Bone Density (Osteopenia) And Osteoporosis?
If you haven’t already read the section above on how to reduce your risk of osteoporosis and fractures, please do, as those recommendations apply to everyone.
If your T-score is -1.0 or above (normal bone density):
- Most people with T-scores of -1.0 and above (i.e. +1.0, +0.5, 0, -0.5, -1.0) do not need to take an osteoporosis medicine.
- Repeat the DEXA scan every 24 months
If your T-score is below -1.0 (osteopenia and osteoporosis):
- Your physician will discuss the possibility of starting a medication that reduces bone loss (i.e. bisphosphonates or raloxifene therapy)
- If you have a T-score between -1.0 and -2.5 (low bone density or osteopenia) and a “higher-risk” FRAX score (3% or higher at the hip or 20% or higher at other sites), you may need to consider taking an osteoporosis medicine.
- If you have a T-score between -1.0 and -2.5 (low bone density or osteopenia) and a “lower-risk” FRAX score (less than 3% at the hip or less than 20% at other sites), you may not need an osteoporosis medicine
- All people with T-scores of -2.5 and below (osteoporosis; i.e. -2.5, -3.0, -3.5, -4.0) should consider taking an osteoporosis medicine.
- Repeat the DEXA scan annually
If You Require An Osteoporosis Medicine, There Are Many Options:
There are two main categories of osteoporosis medications, those that slow bone loss and those that increase the rate of bone formation.
The decision of which medication to select is based on MANY factors:
Some medications are approved for either men or women or both. Some are approved for premenopausal women, while others are more appropriate for older women. The choice of medication may relate to the severity of your osteoporosis or on your other medical conditions. You may even decide on your choice of medication based on your preference of taking it in pill, liquid or intravenous form. Some are given daily, weekly, monthly or even once per year.
Since the choice of which medication to take for you is so complicated and depends on numerous factors, this topic will be most appropriately left for you to discuss with your physician. You can also read more about these medications and options on the National Osteoporosis Foundation site.
In 2009, a team of academic oncology providers and researchers, of the National Comprehensive Cancer Network (NCCN), developed some helpful guidelines called “Bone Health in Cancer Care.” The figure below is a summary of their recommendations for screening and treatment of osteopenia and osteoporosis in patients with a diagnosis of cancer. This basically summarizes many of the topics covered above in the blog post.
**New studies are now indicating that it may be important to take a ‘break’ every 5-years from these medications to give your bones the ability to actually get stronger.**
The Bottom Line:
Many cancer patients and survivors are at an increased risk of developing osteopenia, osteoporosis and bone fractures. This can develop as a result of various bone depleting therapies, nutritional deficiencies, inadequate physical activity, tobacco use and other factors.
Fortunately, with appropriate BMD screening and healthful lifestyle habits, this risk can be significantly reduced.
For those who already are at a high risk of bone fractures, osteoporosis medications will generally be recommended.