Reducing The Risk Of Hip Fracture -— Another Benefit Of The High Blood Pressure-Lowering Water Pills (Thiazide Diuretics)

Research published in the September 2003 issue of the Annals of Internal Medicine provides more supportive evidence that the high blood pressure-lowering thiazide diuretics, or water pills, may protect against hip fractures.

The idea is not new; ten years ago, in the 1993 edition of Worst Pills, Best Pills we wrote:

There is now good evidence that another benefit of thiazide diuretics such as hydrochlorothiazide [HYDRODIURIL] is that they significantly decrease the rate of bone mineral loss in both men and women because they reduce the amount of calcium lost in the urine. An increasing number of researchers think that this will also decrease the number of fractures.

Most hip fractures in older adults are related to osteoporosis. These can be catastrophic events leading to hospitalization, disability and even death. Clearly, effective strategies to prevent hip fractures would have important positive implications for the healthcare system — but most importantly, for patients.

Several studies — so-called “observational studies,” have found that the use of a thiazide diuretic is associated with decreased risk of hip fracture. However, observational studies are not the strongest type of evidence for recommending the use of a drug. The Food and Drug Administration (FDA), for example, would not approve a new drug, or a new use for an old one, on the basis of observational studies alone because they cannot establish a cause-and-effect relationship between use of the drug and a clinical benefit for patients. The best evidence — what scientists call the “gold standard” for a drug’s effectiveness — comes from a randomized controlled clinical trial.

The new Annals of Internal Medicine study was not such a randomized trial but simply another observational study. It involved the citizens of Ommoord, a suburb of Rotterdam in the Netherlands, who were 55 years of age or older. Of the 10,275 persons who were eligible, 7,983 (78%) agreed to participate. All of the participants were followed from June 1, 1991 until they had experienced a hip fracture, died, or reached the end of the study on December 31, 1999.

During the study a total of 281 hip fractures occurred. Of these, 221 occurred in women and 60 in men. The major finding of the study was that using a thiazide diuretic for more than one year was associated with lowered risk of hip fracture. This lower risk was statistically significant compared to those people in the study who were not taking a thiazide diuretic, thus confirming a protective role for the thiazides.

The lower risk of hip fracture disappeared approximately four months after thiazide diuretic use was stopped.

Thiazide diuretics are not approved by the FDA to reduce the risk of hip or any other type of fracture and we cannot recommend that they be used solely in this manner. However, this family of high blood pressure-lowering drugs has been recommended for years as the best initial treatment of high blood pressure because of the positive results seen in randomized controlled trials (see Worst Pills, Best Pills News February 2003).

We view the results of the observational studies showing a reduction in the risk of hip fracture as one more reason why thiazide diuretics should be part of the treatment for high blood pressure.

Another advantageous thing about thiazides: they’re cheap. At a large chain pharmacy in the Washington DC area, a three-month supply of a typical dose regimen for generic hydrochlorothiazide sells for just under $12.

What You Can Do

If you have high blood pressure and part of your treatment does not include a thiazide diuretic you should ask your doctor — why not?