Daily Health Advices

As levels of parathyroid hormone rise, so does the risk of falls in older, well-functioning women and men with diabetes, according to findings from the Using data from the Health, Aging and Body Composition (Health ABC) Study.

Findings from a number of studies have suggested that high levels of parathyroid hormone promote protein catabolism and muscle weakness. In terms of falls, some reports have indicated that high levels of the hormone increase the risk, while others have not found this.

Using data from a subset of participants in Health ABC, Dr. Denise K. Houston, from Wake Forest University School of Medicine in Winston-Salem, North Carolina, and co-researchers examined the impact of parathyroid hormone levels on the risk of falls in 472 community-dwelling adults, 70 to 79 years of age, with diabetes mellitus.

Parathyroid hormone levels were measured at baseline and self reports were used to assess falls over the next 12 months, the researchers report. The findings are reported in the November issue of the Journal of the American Geriatrics Society.

Roughly 30% of the subjects reported a fall, and the average level of parathyroid hormone was significantly higher in those who fell than in those who did not: 62.6 vs. 53.5 pg/mL (p = 0.01).

After adjusting for age, gender, race, and other possible confounders, the authors calculate that each standard deviation increase (36 pg/mL) in baseline serum hormone levels translated into a 30% increase in the risk of self-reported fall.

On final analysis, accounting for physical performance, kidney function, medication and supplement use, and chronic conditions, the odds ratio fell slightly to 1.26, the report indicates.

This suggests that “physical performance did not mediate the association between parathyroid hormone and falls,” the authors state.

“Further investigation,” they conclude, “aimed at understanding the underlying mechanism for the association between serum parathyroid hormone on muscle strength, physical performance, and falls is needed.”

Clinical Context

More than one third of community-dwelling elderly adults falls each year, and approximately 1 in 10 falls results in serious injury, sometimes leading to pain, functional limitations, disability, long-term care placement, and even death. Diabetes mellitus increases fall risk, possibly because of related peripheral neuropathy, poor vision, and impaired renal function.

Independent of vitamin D levels, serum parathyroid hormone levels may help maintain muscle integrity and physical function, thereby helping to prevent falls. With increasing age, serum parathyroid hormone levels increase, most likely because of low vitamin D levels, impaired kidney function, low calcium intake or impaired calcium absorption from malabsorption, and parathyroid gland resistance to suppression of parathyroid hormone secretion by serum 1,25(OH)2D3, the active form of vitamin D.