A news reporter interviews DR ANIRBAN BISWAS (MD), famous diabetes doctor in Delhi with over 15 years of experience. He is a senior consultant at FORTIS C- DOC hospital & NATIONAL HEART INSTITUTE. 

Q 1. Do diabetic patients have low bone density? 

A. NO, It is not so. Type 1 diabetes is generally linked to lower-than-average bone density, but bone density tends to be higher in people with Type 2 diabetes. The puzzling thing has been that both groups are more prone to bone fracture. Moreover, type 2 diabetic patients tend to have a higher fracture risk even at higher BMD (Bone mineral density).

 Q 2. What is the reason behind this increased risk of fracture in diabetic patients? 

A. According to a study, published in late May in the journal Nature Communications, which ran a systematic analysis of hyperglycemia’s effects on bone metabolism using bone marrow samples from diabetic and healthy mice. “They found that the levels of succinate, a key molecule involved in energy production, are over 20 times higher in the diabetic mice. It turns out that succinate also acts as a simulator of bone breakdown.” 

Q 3. Could you please elaborate it more?

 A. Okay, let me explain in a simple way. Look, Our bodies continually break down and absorb old bone and form new bone tissue. The study appears to show that the high levels of succinate keep the body from maintaining the right balance of breakdown and bone formation; researchers also found that the hyperglycemic mice had considerably lower levels of spongy yet strong bone mass, called trabecular bone. 

Q 4. What is the importance of this finding? 

A. “The results are important because diabetics have a significantly higher fracture risk and their healing process is always delayed”. “In this study, the hyperglycemic mice had increased bone resorption [the breakdown and absorption of old bone], which outpaced the formation of new bone. This has implications for bone protection as well as for the treatment of diabetes-associated collateral bone damage." If these findings are confirmed, finding ways to regulate succinate levels could provide promising treatments for reducing bone fractures, though it’s worth noting that diabetes treatments that have been found successful for mice sometimes don’t work with humans. 

Q 5. Is there a role of stem -cell therapy in preventing fractures?

 A. Earlier this year, Stanford researchers also published a paper showing that activating bone stem cells helped repair fractures in diabetic mice. Their study, published in January in the journal Science Translational Medicine, found that applying a protein to the site of the fracture promoted the expression of key signalling proteins.

 Q 6. What are the sites commonly involved in a fracture? 

A. There is increased the risk of fracture in hip, spine and lower limbs, as per a metanalysis in patients with diabetes. 

Q 7. What about antidiabetic drugs, do they increase the risk of fracture? 

A. YES, the thiazolidinediones, namely pioglitazone and rosiglitazone ( not used much in India ) have shown to increase the risk of fractures in diabetic patients. Very recently, Canagliflozin (an SGLT-2 receptor inhibitor) was also found to be associated with increased risk of fractures. 

Q 8. What is your take-home message? 

A. All diabetic patients should be subjected to BMD test and also calcium & Vitamin D levels and treated accordingly, particularly the postmenopausal females.