I have no personal experience with osteoporosis. But, I just wanted to provide some information about the use of glucocorticoids (Methotrexate) and its link to Osteoporosis:
High doses or prolonged use of Methotrexate can cause Osteoporosis. If you are taking 10 or more milligrams per day of prednisone, Methotrexate or another steroid for more than three months, your doctor should have prescribed 1,500 mg of calcium, 400 i.u. of vitamin D to take daily to prevent osteoporosis.
Since you have osteoporosis with your Lupus and are continuing to take Prednisone and/or Methotrexate, then your doctor should prescribe osteoporosis drugs to try to prevent further progession.
Osteonecrosis (bone thinning and fragility) is an unfortunate complication of SLE or glucocorticoid (Methotrexate) use. Osteonecrosis most often affects young adults aged 30–50 years and, if the hip is involved, total joint replacement is commonly required. Osteoporosis is defined as a reduction in bone strength by becoming fragile or thin. This reduction leads to bone fractures, even when very low forces are applied.
Individuals achieve peak bone mass about the age of 20 years. After peak bone mass is achieved, bones are constantly remodeled through a tightly coupled process of bone resorption followed by formation. This type of coupled remodeling of the skeleton continues until women become menopausal, at which time reduced levels of estrogen and increased levels of follicle-stimulating hormone stimulate accelerated bone remodeling, and gradual bone loss occurs. In men, age-related bone loss occurs in the eighth decade of life. By the age of 75 years, women have lost nearly 30% of their bone mass and nearly one in two women will have osteoporosis and consequently a high risk of fracture.
Bone remodeling is a tightly orchestrated process in which osteoclasts (cells that resorb bone) attach to the bone surface and remove bone. After a resorption pit is formed, osteoblasts (bone-forming cells) migrate into it and produce new bone, referred to as osteoid, which then mineralizes. Under normal circumstances, the exact amount of bone that is removed is replaced. Physiologic states that are associated with high levels of osteoclast activity or low levels of osteoblast activity can, however, uncouple this process and bone loss can occur.
SLE patients have lower bone mass in the lumbar spine than persons of similar age who do not have Lupus. Patients with SLE also have a significantly higher risk of vertebral fractures. The majority of these fractures occur in premenopausal women with Lupus. Some of the traditional risk factors for osteopenia and fractures in the majority population are present in SLE patients.
Risk factors for osteoporosis in SLE patients include the use of glucocorticoids, and it has been found that long term use of glucocorticoids was a strong predictor of fractures. In addition, cyclophosphamide have been found to reduce bone mass, by altering estrogen and the follicle-stimulating hormone levels.
In Summary, according to The Lupus Foundation of America:
Systemic and localized inflammation caused by Lupus results in elevated levels of cytokines and proteins that alter bone remodeling and increase bone loss. Tumor necrosis factor, interleukin 6, oxidized low-density lipoprotein (a substrate for lipoprotein lipase and RANKL all either increase osteoclast-driven bone resorption or reduce osteoblast-driven bone formation. In addition, the traditional osteoporosis risk factors are also relevant in patients with SLE (e.g. age, weight, history of smoking, peak bone mass, history of fracture as an adult, and family history of fracture). There are metabolic conditions associated with SLE that can also increase the risk of osteoporosis: low serum vitamin D levels, low thyroid activity and, possibly, a high homocysteine level. Lastly, to reduce their disease activity, patients with SLE are treated with medications that can have adverse effects on bone strength (i.e. glucocorticoids, cyclophosphamide and GnRH agonists). Abbreviations: CRP, C-reactive protein; GnRH, gonadotropin-releasing hormone; IL, interleukin; RANKL, receptor activator of nuclear factor B ligand; SLE, systemic lupus erythematosus; TNF, tumor necrosis factor.
I hope this information has been helpful.
Peace and Blessings
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