WEDNESDAY, May 13 (HealthDay News) -- The more pills that kidney dialysis patients take, the more side effects they suffer and the worse their quality of life, a new study finds.

Dialysis patients have to take more pills than most patients with other chronic diseases. In this study, researchers at the Los Angeles Biomedical Research Institute looked at the "pill burden" in 233 dialysis patients in the United States.

The patients took an average of 19 pills a day, but 25 percent took more than 25 pills a day. Patients with a high pill burden reported poorer physical health.

Phosphate binders, medications that control the level of phosphorous in the blood, accounted for about half of the daily pill burden. The study found that 62 percent of patients didn't take these medications as directed. The more phosphate binders patients were prescribed, the less likely they were to take the medications as directed, and the less likely they were to have their blood phosphorous levels under control.

The researchers said their findings suggest that increasing the number of prescribed pills doesn't improve control of phosphorous levels and may result in poorer health-related quality of life.

Any efforts to reduce dialysis patients' pill burden must address the number of prescribed phosphate binders, the researchers said.

The study, funded by Shire Pharmaceuticals, appears in an upcoming issue of the Clinical Journal of the American Society of Nephrology.

More information

The National Kidney Foundation has more about dialysis.