Diuretics are medications that result in increased water and sodium loss from filtered blood in the kidneys; they are used to treat hypertension and fluid overload. There are three different types of diuretics -- loop, potassium-sparing and thiazide diuretics -- and they all function differently in the kidneys. The use of several diuretics are associated with altered calcium metabolism, raising concerns about the increased likelihood of diuretic-related osteoporosis.
Bone Mineral Density and Osteoporosis
The bones provide support for body movements and protection for internal organs; without strong bones, you are vulnerable to fractures that can result in severe injuries to organs and limitation in function. The bones are strengthened by calcium, a mineral that is mainly obtained from dietary sources. Sex hormones, such as estrogen and testosterone, are also needed to maintain adequate bone mineral density and prevent the development of osteoporosis. Maintaining adequate bone mineral density may be difficult in poor dietary conditions and adverse health.
People at Risk for Osteoporosis
The risk for osteoporosis increases with age but is more pronounced in females, especially after menopause due to low estrogen. People with poor dietary habits are likely to have low intake of calcium and vitamin D, which increases the likelihood for the development of osteoporosis. According to a 2009 "Journal of the American Geriatrics Society" study, in comparison to non-users, the use of loop diuretics resulted in a significant increases in the rate of bone loss in the hips; based on this study, the use of loop diuretics in people with other risk factors for osteoporosis should be avoided, if possible.
Diuretics and Calcium
A diuretic that increases the risk for osteoporosis may alter the metabolism of calcium. According to the 2009 study, the use of loop diuretics resulted in increased calcium excretion in the urine; prolonged use is likely to be associated with bone density loss. Thiazide diuretics prevent calcium excretion in the kidneys, thereby resulting in elevated levels of calcium in the blood; as a result, thiazide is unlikely to be associated with osteoporosis.
Management of Diuretic-Associated Osteoporosis
The initial step in the management of diuretic-associated osteoporosis is to stop or reduce the dose of the diuretic; since loop diuretics are effective in treating hypertension and preventing the development of life-threatening heart disease, it may be difficult to avoid their use. However, other measures, such as increasing dietary intake of calcium and vitamin D, adequate sunlight exposure and physical exercise, can help reduce the risk for diuretic-related osteoporosis. According to the Office of Dietary Supplements, the supplementation of vitamin D with calcium results in small increases in bone density; bone density was not improved with vitamin D supplementation alone.
References
- "Journal of American Geriatrics Society"; Loop Diuretic Use and Rates of Hip Bone Loss, and Risk of Falls and Fractures in Older Women; Lionel S. Lim, M.D., M.P.H., et al.; 2009
- "Pocket Medicine"; Nephrology; Marc S. Sabatine M.D., M.P.H.; 2004
- "Harrison's Principles of Internal Medicine"; Dennis L. Kasper M.D., et al.; 2005
- Office of Dietary Supplements: Vitamin D
