Researchers find dose-response relationship in those aged 70 or older taking the drug
FRIDAY, April 29 (HealthDay News) -- Older people who take levothyroxine may be at risk for fractures, particularly if their cumulative doses are medium or high, according to research published online April 28 in BMJ.
Marci R. Turner, M.D., of the University of Toronto, and colleagues followed 213,511 levothyroxine users age 70 or older for a mean of 3.8 years to assess levothyroxine dose-related risk of fracture in older adults.
The researchers found that fractures occurred in 22,236 subjects (10.4 percent), 88 percent of whom were women. Fractures were more likely in current users rather than remote users (adjusted odds ratio, 1.88), and those taking high and medium cumulative doses (more than 0.093 mg/day and 0.044 to 0.093 mg/day) had a significantly higher risk of fracture than those taking low cumulative doses.
"Among adults aged 70 or more, current levothyroxine treatment was associated with a significantly increased risk of fracture, with a strong dose-response relation. Ongoing monitoring of levothyroxine dose is important to avoid overtreatment in this population," the authors write.