Dr Thomas Paul and Dr Kripa Elizabeth Cherian discuss the importance of taking care of your bone health.The increased prevalence of both Diabetes mellitus and osteoporosis in the elderly population warrants that due attention be given to the simultaneous management of both conditions. The term “diabetic bone disease” refers to changes in bone growth, bone remodelling and bone mineral density with an increased risk of fracture that results from the state of uncontrolled hyperglycaemia (high blood glucose level). In recent times, there has been ample evidence to confirm that Diabetes is associated with increased bone fragility and consequent fractures. This article will look at the burden of diabetic bone disease, the plausible mechanisms and the evaluation and management of bone health in people with Diabetes..Diabetic bone disease - the burdenThe presence of Diabetes and bone fragility constitute “twin burdens” The presence of Diabetes is associated with an increased risk of fractures. More than 90 per cent of people living with Diabetes have Type 2 Diabetes in which there is a paradoxically increased bone mineral density. Despite the increased bone mineral density, there is an alteration in bone microarchitecture, which leads to heightened bone fragility.The reasons for an increased risk of fracture in Diabetes is two-fold: firstly, the deterioration of bone microarchitecture can predispose to an increased fracture risk; secondly, various complications of Diabetes such as poor vision and advanced retinopathy, severe peripheral neuropathy, polypharmacy leading to hypoglycaemia may result in an increased tendency to falls and subsequent fractures.Skeletal health in people living with Diabetes seems to be an overlooked entity. Previous studies have shown that the mortality following a hip fracture is as high as 20 per cent in the first year after a fracture. The occurrence of fractures also leads to an increase in societal costs, increased dependence for activities of daily living and increased caregiver burden. This underscores the need for early screening for bone fragility and timely initiation of treatment as appropriate..MechanismsThe mechanisms underlying adverse bone health in Diabetes is not clear. The mechanisms vary in Type 1 and Type 2 Diabetes. Some of the mechanisms include a deposition of advanced glycation end products in the collagen framework of the bone leading to altered material properties; other mechanisms include microvascular alterations in the bone and altered musculature.In addition, in individuals with early onset of Type 1 Diabetes, there is absolute insulin deficiency and consequent impaired bone formation and development due to lack in the anabolic effects of insulin. People with Type 1 Diabetes may never reach their peak bone mass leading to an increased risk of fractures. There is also poor bone healing and regeneration secondary to uncontrolled hyperglycaemia. Other factors that lead to an increased risk of fractures include an increased propensity to falls secondary to impaired vision, advanced neuropathy and hypoglycaemia.EvaluationThe evaluation of bone health in people with Diabetes include a thorough clinical examination, blood investigations pertaining to bone health, relevant radiology and DXA (Dual Energy X-ray Absorptiometry) scan. It is important to gauge the risk for osteoporosis.All women after menopause and men aged over 50 years are at a high risk for bone loss. Besides these factors, smoking, alcohol consumption, the use of glucocorticoids, previous history of a fracture, the presence of fracture in a parent, inflammatory conditions such as rheumatoid arthritis, all portend a high risk of osteoporosis. It is also important to assess the risk factors for a fall, as usually falls from standing height result in “osteoporotic fragility fractures.”Poor vision, severe peripheral neuropathy especially in the context of uncontrolled Diabetes, osteoarthritis and unstable joints, neurodegenerative diseases that are common in the elderly, the use of certain anti-hypertensive medications, high dose of oral anti-diabetic agents and insulin that causes low blood glucose levels may all predispose to falls.Associated conditions such as a recent onset of severe bony pains, weight loss and loss of appetite may be related to an underlying malignancy and may warrant additional evaluation. Endocrine-related conditions such as hyperthyroidism may also result in bone loss.Relevant investigations would include blood samples for calcium, phosphate, alkaline phosphatase, 25-hydroxy vitamin D, X-ray of the spine and creatinine. It is also important to assess the extent of glycaemic control by measuring fasting and postprandial blood glucose as well the glycated haemoglobin (HbA1C) levels.The specific investigation to diagnose osteoporosis is a dual energy X-ray absorptiometry scan, which measures the people with Diabetes's bone mineral density and compares it with a reference standard. If bone mineral density is -2.5 or lower in people with Diabetes this is defined as osteoporosis and warrants treatment.The presence of a normal bone mineral density with prevalent or a history of trivial- trauma fractures also require treatment. A paradox that is encountered in Diabetes is the bone mineral density of the people with Diabetes may be normal or apparently higher than expected; this does not necessarily guarantee strong bones as the quality of the bone in Diabetes is poor, and this may not be captured by bone mineral density measurement.The other tools on the DXA scanner that may convey additional information about bone strength include the trabecular bone score, which gives information about the lumbar spine and the hip structural analysis, which furnishes information about the geometrical aspects of the hip and potential to fracture. DXA may also be utilised to assess the presence of fractures involving the thoracic and the lumbar spine. This is done using the vertebral fracture assessment tool, which is incorporated as an additional software in the scanner..TreatmentTreatment for osteoporosis involves both general measures as well as pharmacological measures.General measures include the following:Diet: Ensure adequate dietary intake of calcium through calcium rich foods such as dairy products that include milk, curd, yoghurt, millets, ragi, fish and so on. Sufficient sun exposure may be recommended for synthesis of vitamin D in the skin. This involves exposure to sunrays for at least twenty minutes between 11 am and 2 pm. In relation to Diabetes adherence to a diet that encompasses adequate and appropriate intake of carbohydrates, proteins, fats and micronutrients, in consultation with a dietitian is recommended. Weight reduction is recommended in obese individuals. It is also recommended to quit smoking and avoid alcohol consumption.Physical activity: Weight bearing exercises help in preserving bone density. Avoid exercises that involve twisting movements of the spine. In addition, balance and posture exercises with gait training may be essential to prevent falls.Fall prevention measures: The importance of fall-prevention measures cannot be over-emphasized. Ensure adequate lighting at home. Care must be taken to avoid slippery floors and stumbling over objects over the floor. Provision of hand-rails will assist in walking with caution. Those with postural hypotension may need to make graded changes in posture to avoid sudden falls.Control of co-morbidities: Blood glucose and blood pressure levels are to be controlled. Hypoglycaemia is to be avoided. Glucocorticoids if indicated, should be reduced to the minimum required dose..Specific treatmentCalcium and vitamin D supplements:The recommended daily intake of calcium is about 1000 mg daily, and that of vitamin D (cholecalciferol) is 1000-2000 IU daily. A calcium and vitamin D replete status needs to be ensured prior to starting specific treatment.Anti-resorptives for osteoporosis:These include oral medications such as Alendronate (70 mg weekly), Ibandronate (150 mg monthly) and Risendronate (35 mg weekly). Injectable agents include Zoledronate (4-5 mg annually) which is the preferred agent in case of a hip fracture. Anti-resorptive act by inhibiting excessive bone destruction. Denosumab is a newer anti-resorptive, which is given as an injection (60 mg sub-cutaneous), every six months.Anabolic agents for osteoporosis:The drugs in this category include Teriparatide administered as a daily injection 20 mcg daily for two years. This promotes bone formation and is the preferred agent in the presence of vertebral fractures. Abaloparatide, the other anabolic agent is not available widely.Romosozumab, recently approved for osteoporosis is highly potent and has both anabolic and anti-resorptive properties.The specific agent to be used is decided by the treating physician and is tailored to the person with Diabetes, in the context of his co-morbidities, severity of osteoporosis, presence or history of fractures and affordability.To concludeIt goes without saying that people living with Diabetes are more prone to poor bone health and quality and an increased propensity to fractures. It is essential that those at risk be screened in time. Adequate calcium and vitamin D nutrition should be emphasised.Fall prevention measures ought to be taught to people with Diabetes and their caregivers. The decision on therapeutic management is made by the treating physician and is usually tailored to the individual people with Diabetes.