Hormone replacement therapy (HRT) is used when there is a loss of the body’s ability to produce estrogen and progestin resulting in an intolerable state. This can occur when there is a natural decline in ovarian function, surgical removal of the ovaries, or with Turner’s syndrome. As noted in Woo & Robertson (2016), there are several guiding organizations that support the replacement of estrogen and/or progestin for the treatment of menopause when symptoms become moderate to severe. However, estrogen is not recommended as a treatment or prevention method for chronic illnesses other than osteoporosis. The lowest dose possible to control symptoms is the goal when prescribing HRT.
Normal bone is developed through three phases of constant remodeling. Osteoblasts and osteoclasts communicate to maintain a balance of bone resorption and formation. Peak bone mass is determined by genetics primarily but also by diet, endocrine status, and physical activity. Parathyroid hormone (PTH) is released if the body’s serum calcium levels are low to stimulate osteoclasts to reabsorb bone to satisfy the body’s calcium needs. Estrogen reduces this action. Osteoporosis is diagnosed when bone density is 2.5 standard deviations below average. Risk factors for osteoporosis include family history, 70 years of age or greater, thin body frame, fair complexion, low calcium and/or vitamin D diet, minimal sun exposure, weight less than 70 kilograms, and a sedentary lifestyle. Weight bearing exercises as women age is an important activity to assist in the stimulation of bone remodeling. African-American women have higher bone density but traditionally have a lower calcium intake. Asian women are at high risk for osteoporosis and traditionally consume inadequate amounts of calcium. Hispanic women have similar risks as Caucasian women.
Below is information previously provided in the endocrine system section of the course. As explained there, osteoporosis is influenced and associated with the endocrine system as well as the muskuloskeletal system. However, this is the section where you are studying about osteoporosis as it relates to hormones and osteoporosis itself so the information is provided here as well.