People with lupus have a greater-than-average risk of developing osteoporosis. This article explains the relationship between lupus, bone health and osteoporosis, as well as ways to mitigate your own risks and manage osteoporosis. Please visit our main condition page for a complete overview of lupus.
Osteoporosis is a “silent” skeletal disorder caused by the loss of bone mineral content. It is marked by low bone mass and density, microscopic deterioration within the bone, and decreasing bone strength, leading to bone fragility and an increased risk of fracture. Osteoporosis occurs when your body makes too little bone, loses too much bone, or when there is a combination of both of these factors.
According to estimates of the US Department of Health and Human Services (HHS) Healthy People 2020 Initiative:
In general, more women than men suffer from bone loss and osteoporosis.
At the same time, some young persons in their teens and twenties (particularly those with a history of bone fracture, corticosteroid drug use, nutritional deficiencies or eating disorders which result in abnormally low body weights), are also diagnosed with low bone mass.
Bone is living tissue, and even as adults we are constantly remodeling our whole skeleton! In the normal bone growth cycle, our bodies continually:
Bone remodeling is the body’s way of breaking down weak bone and rebuilding stronger bone. At around age 27 to 30, our bones are strongest and at peak mineral density. After this age, there is a slow and steady decline in bone strength due to an age-related slowdown in bone formation. It is this imbalance between bone formation and bone resorption that leads to bone loss and an accompanying increased risk of developing osteopenia and osteoporosis.
Poor bone quality increases the risk of fractures, and hip fractures in particular, especially so-called low energy fractures. These are fractures that occur as the result of a simple trip and fall from a standing height, as opposed to traumatic fractures such as those caused by an automobile accident. People who experience low-energy fractures are at risk of having more in the future, and of experiencing some form of disability – ranging from mild impairment in performing activities of daily living, to significant, permanent disability. Mortality rates have been reported as high as 20% within the first year after an osteoporosis hip fracture, due to complications associated with age and immobility.
Inflammation caused by lupus affects many body tissues, including the bones, and inflammation contributes to the loss of bone mineralization. Bone mineralization is an ongoing process in which the body absorbs minerals to build and maintain healthy bones. These minerals include calcium, magnesium, iron, phosphorous and zinc, as well as Vitamin D – all of which should be ingested in adequate amounts to properly support bone strength.
Inflammatory processes in the bone near the joints can decrease the mineral content of the bone, leading to the development of osteopenia (moderately low bone density) as well as osteoporosis (significantly low bone density). Studies of women with lupus have found that they have an increase in the bone loss that leads to osteoporosis, including as much as a fivefold increase in the risk of a bone fracture, compared to that of healthy women. Additionally, people with lupus also suffer loss of height and periodontal bone loss (loss of bone around the teeth in the jaw and skull).
Inflammation is only one of several factors contributing to bone loss in people with lupus. Others include:
A condition called avascular necrosis (also known as osteonecrosis) occurs in about 10% of lupus patients and is related to steroid use. This usually occurs in the hip joints. The condition is characterized by reduced blood supply to the bone along with increased swelling and pressure. Bone weakens, causing tiny cracks, which lead to joint pain, decreased movement within the joint, and muscle spasm. At the end stage, the bone collapses under stress.
Chronic inflammation associated with lupus and medications used to treat the disease – particularly prednisone and other corticosteroid drugs (“steroids”) – all contribute to the risk. Bone removal occurs at an increased rate with certain diseases, such as lupus. The body tries to replace bone that was removed, but as we age or when we are coping with lupus, this process slows down. This imbalance between bone formation and bone resorption leads to bone loss.
In addition, inadequate intake or absorption of bone-building calcium and Vitamin D, and less exercise due to fatigue and pain from lupus, may contribute to a reduction in bone mineralization and progressive bone loss. Many people with lupus are advised to avoid sun exposure, because ultraviolet (UV) light can trigger disease flares in some of these individuals. UV light stimulates the production of Vitamin D in our bodies, an important substance for bone health. Although sun exposure creates only a limited amount of Vitamin D, even so, with lower sun exposure, many people with lupus will be low on Vitamin D and thus at greater risk for developing osteoporosis.
Osteoporosis risk factors individuals have no control over include:
The good news is that we can do things to make bones healthier, stimulate bone formation and slow down bone resorption. For people with lupus, the main treatment approach emphasizes controlling inflammation and preventing organ damage. There are additional approaches to reduce the risk of developing osteoporosis. These include:
Age-related loss of skeletal muscle mass is common, and with it comes diminished function. This may take place in tandem with increased body fat. Low muscle mass translates to low muscle strength. Both weight-bearing and resistance exercises are helpful.
Calcium and vitamin D are key: The preferred approach now favors obtaining calcium through eating a healthy, well-balanced diet, and adding supplements if needed to make up any shortfall.
Good calcium-rich food sources include:
Below are daily requirements of calcium and vitamin D3 – from both diet (food sources) and dietary supplements, measured in international units (IU) and micrograms (mcg).
Women
Premenopausal
1,000 mg calcium
600 IU (15 mcg) vitamin D3
Postmenopausal
1,200 mg calcium
800 IU (20 mcg) vitamin D3
Men
Up to age 70
1,000 mg calcium
600 IU (15 mcg) vitamin D3
Over Age 71
1,200 mg calcium
800 IU (20 mcg) vitamin D3
Calcium is best absorbed when taken in amounts of 500 mg to 600 mg or less at one time, preferably with a meal. Calcium citrate is most easily absorbed and can be taken with or without food. Calcium carbonate is another form of calcium that is more readily available when taken with meals. Calcium is available in liquid, tablet or chewable form. Side effects of calcium consumption can include constipation and kidney stones. Calcium supplements may have interactions with certain medications. In particular, calcium supplements should not be taken within two hours of taking a proton pump inhibitor, such as omeprazole (Prilosec), lansoprazole (Prevacid), famotidine (Pepcid), pantoprazole (Protonix), rabeprazole (Aciphex), dexlansoprazole (Dexilant), esomeprazole (Nexium), etc.
It tends to be difficult to receive enough vitamin D through natural means (exposure to sunlight and food), and so taking supplements may be recommended. Recommendations for vitamin D intake for both men and women are 600 IU (15 mcg) for those under age 70, and 800 IU (20 mcg) for older adults. It is a good idea to have your doctor check your vitamin D level with annual blood tests.
Vitamin D comes in two forms: cholecalciferol (D3), and ergocalciferol (D2). D3 is more easily metabolized. Good sources of vitamin D-rich foods include:
Since osteoporosis is a silent disease and is not associated with pain until a bone is fractured, it is important to have screening tests to look at the quality or mineralization of the bone. Such screening tests include:
Like lupus, osteoporosis is a chronic disease with no cure. Once one is diagnosed with osteoporosis or osteopenia, taking calcium alone is not adequate to restore bone density. And while conservative measures such as diet and exercise can be beneficial for bone health, your physician might suggest a medication to prevent further bone loss. Fortunately, several medications are available for the prevention and treatment of osteoporosis. The decision to undertake treatment is a shared one between you and your doctor. It is important to discuss with your healthcare provider the indications, efficacy, pros and cons of various medications, in addition to any other concerns you might have.
Medical treatment targets various stages in the bone growth cycle, from bone formation to bone resorption. Most medications are designed to slow down bone resorption, and they are called antiresorptives.
Medications that decrease bone breakdown include:
Hormones that decrease bone breakdown include:
Anabolic medications improve the formation of new bone. These are given for a minimum of three months and a maximum of two years per lifetime via a daily injection with a pen injection device. Such medications include:
One medication both decreases bone breakdown and increases bone growth. This drug is an antisclerostin monoclonal antibody that was approved by the Food and Drug Administration in 2019 for postmenopausal women at high risk for fracture. It is given by a subcutaneous injection every month for 12 months.
The most important thing to do if you have osteoporosis is to avoid falling. Falls become more common as people advance in age. Many osteoporosis-related fractures are due to falls, and over 90% of hip fractures are due to falls. More than 33% of adults age 65 will experience a fall in a given year, while over 40% of those over 75 will fall. Falls can be reduced through:
Loss of bone mineral density occurs naturally with the normal aging process. Lupus and its treatment with corticosteroids can increase an individual’s chance of developing a low bone mineral state such as osteopenia or osteoporosis. Screening tests to identify poor bone mineralization are important along with treatment with medications, if indicated. Conservative measures such as diet, supplements, exercises and fall prevention are all important to include in a bone-healthy lifestyle.
Learn about the SLE Workshop and get more information on support services at HSS available for people with lupus and their loved ones by visiting LupusLine®, LANtern® (Lupus Asian Network), and Charla de Lupus (Lupus Chat)®.
Posted: 3/30/2020