Strontium

Susceptibility To Cavities

Strontium has been shown to reduce the incidence of cavities. In a 10-year study, the United States Navy Dental Service examined the teeth of about 270,000 naval recruits. Of those, only 360 were found to be completely free of cavities. Curiously, 10% of those 360 individuals came from a small area around Rossburg, Ohio, where the water contains unusually high concentrations of strontium. Epidemiologic studies have shown that strontium concentrations of 6 to 10 mg/liter in the water supply are associated with a reduced incidence of cavities. Administering these levels of strontium also reduced the incidence of cavities in animal studies. [Gaby, Alan – Preventing and Reversing Osteoporosis, Prima Publishing, Rocklin, CA, 1994]

Osteoporosis / Risk

A large trial including 1,649 osteoporotic postmenopausal women found fewer fractures and increased lumbar bone mass. The subjects received 2 gm/day of strontium ranelate (providing 680 mg strontium) or placebo for three years. Calcium and vitamin D supplements were also given to both groups before and during the study. The authors concluded that “treatment of postmenopausal osteoporosis with strontium ranelate leads to early and sustained reductions in the risk of vertebral fractures.” [N Engl J Med, 2004, Jan 29;350(5):pp.459-6]

Osteoarthritis

In women with osteoporosis and spinal osteoarthritis (OA), treatment with strontium ranelate may delay radiographic progression of spinal OA and reduce back pain.

Dr. Olivier Bruyere from the University of Liege, Belgium and colleagues reviewed the effects of 3 years’ treatment with strontium ranelate on the clinical and structural progression of spinal OA in 1105 women. As participants in the Spinal Osteoporosis Therapeutic Intervention and Treatment of Peripheral Osteoporosis trials, the women had received either strontium ranelate (n=566) or placebo (n=539).

The researchers found that the proportion of patients with worsening overall spinal OA score was reduced by 42% in the strontium ranelate group relative to the placebo group.

In addition, significantly more patients in the strontium ranelate group had improvement in back pain after 3 years compared with placebo. There were no significant between-group differences in health-related quality of life, however.

Strontium ranelate is indicated for the treatment of postmenopausal osteoporosis and has been shown to reduce the risk of vertebral and hip fractures, the authors note. They point out that strontium ranelate is also being studied in patients with OA of the knee.

The current findings, the authors say, suggest that “strontium ranelate may have symptom- and structure-modifying effects in women with osteoporosis and OA.”

“This study has implications not only in the potential treatment of chronic back pain, but also for progression of OA at other sites,” the researchers conclude.

The study was supported by a research grant from French pharmaceutical company Servier, which manufactures strontium ranelate. [Ann Rheum Dis 2008;67:pp.335-339]