Common, cheap osteoporosis drug promising for T2D

The osteoporosis drug alendronate halves the risk of developing type 2 diabetes (T2D) in a nationwide, retrospective, case-control study of nearly 700,000 patients from Denmark.

The longer the patients took the drug, the lower the odds of developing T2D. Patients taking alendronate for at least 8 years were 53 percent less likely to be diagnosed with the disease compared with those who had never taken the drug. Surprisingly, taking alendronate for shorter periods also had significant benefits for patients.

“Excitingly, our research suggests that alendronate, an inexpensive medicine widely used to treat osteoporosis, may also protect against T2D,” said study author Dr Rikke Viggers from Aalborg University Hospital in Aalborg, Denmark. “We believe doctors should consider this when prescribing osteoporosis drugs to those with pre-diabetes or at high risk for T2D,” she said.

T2D can lead to other serious health issues such as stroke, heart disease, blindness, and limb amputation. “Anything that prevents or delays it will also reduce a person’s risk of all these other conditions,” Viggers pointed out.

Osteoporosis and diabetes: Finding the link

Experts have long recognized the link between osteoporosis and diabetes. Patients with diabetes are known to be at high risk of osteoporosis-related fractures, but exactly why this is the case is still unclear.

Using data from the national Danish Patient Registry, Viggers and team sought to investigate the link between osteoporosis and diabetes – 163,588 individuals aged 50 and older who had T2D after 2008 were identified and matched with 490,764 healthy controls of the same age and gender. [EASD 2021, abstract 71]

Roughly two-thirds of participants were between 50 and 60 years and a quarter was in their 70s. Fifty-five percent were male. Those with type 1 diabetes were excluded from the analysis.

Additionally, individuals who filled prescriptions for alendronate until 2018 were identified. After controlling for multiple risk factors, including smoking history, alcohol use, obesity, income, and marital status among others,  those taking alendronate were 36 percent less likely to have new-onset diabetes than the age- and gender-matched controls who had never taken the drug (odds ratio [OR], 0.64). The odds of T2D were even lower among those who took alendronate for 8 years vs the never-users (OR, 0.47).

Causality cannot be inferred

As this is a registry-based study, Viggers cautioned that causality cannot be inferred. “We do not know if this effect of alendronate is real and what the mechanisms are.”

She speculated that it could be a direct effect on peripheral tissues, for example, muscle and adipose tissue, or an indirect effect through bone metabolites that may impact glucose metabolism.

The findings need to be confirmed in a randomized controlled trial, commented Dr Charles Vega from the University of California Irvine in Irvine, California, US.  “This is an interesting retrospective analysis but should be verified with other data.”