How to manage a 70-year-old patient with Chronic Kidney Disease (CKD) stage 3b, osteopenia on Dual-Energy X-ray Absorptiometry (DEXA) scan, and a history of previous fractures, who experiences severe constipation with calcium supplements?

From the Guidelines

For a 70-year-old patient with CKD stage 3b, osteopenia, previous fractures, and calcium supplement intolerance, I recommend using non-calcium-based treatments to manage bone health. Start with vitamin D supplementation (ergocalciferol 50,000 IU weekly for 8-12 weeks, then 800-1000 IU daily maintenance) to correct any deficiency, as suggested by the 2017 American College of Rheumatology guideline for the prevention and treatment of glucocorticoid-induced osteoporosis 1. Consider denosumab (Prolia) 60 mg subcutaneously every 6 months as the preferred osteoporosis medication, as it doesn't require renal clearance and is safe in CKD, according to the Kidney Disease: Improving Global Outcomes 2017 clinical practice guideline update 1. Avoid bisphosphonates due to reduced renal function. Encourage weight-bearing exercise within the patient's capabilities (walking 30 minutes daily if possible) and fall prevention measures including home safety assessment, proper footwear, and balance training. Monitor renal function every 3-4 months with eGFR and electrolytes, and check vitamin D levels and bone mineral density periodically. For dietary calcium, aim for 1000-1200 mg daily through food sources like dairy alternatives, fortified plant milks, and leafy greens rather than supplements, as recommended by the K/DOQI clinical practice guidelines for bone metabolism and disease in chronic kidney disease 1. This approach addresses bone health while avoiding constipation issues from calcium supplements and protecting kidney function, which is particularly important as both CKD and osteoporosis treatments can affect mineral metabolism. Key considerations include:

• Avoiding hypercalcemia, which may be harmful in all GFR categories of CKD 1
• Restricting the use of calcium-based phosphate binders in patients with hyperphosphatemia across the CKD spectrum 1
• Treating patients with PTH values that are progressively increasing or persistently above the upper limit of normal, rather than basing treatment on a single elevated value 1

From the FDA Drug Label

Advise patients with advanced chronic kidney disease, including those who are dialysis-dependent, about the symptoms of hypocalcemia and the importance of maintaining serum calcium levels with adequate calcium and activated vitamin D supplementation Advise these patients to have their serum calcium measured weekly for the first month after Prolia administration and monthly thereafter

The patient has chronic kidney disease stage 3b and osteopenia, and had a previous fracture history. Given the patient's history of constipation with calcium supplements, alternative treatments or adjustments to the calcium supplementation regimen should be considered to manage hypocalcemia risk.

• The patient should be advised to maintain adequate calcium and vitamin D supplementation.
• Serum calcium levels should be monitored weekly for the first month after denosumab administration and monthly thereafter.
• The patient should be informed about the symptoms of hypocalcemia and the importance of maintaining serum calcium levels.
• Consider alternative treatments for osteopenia that do not exacerbate constipation. 2 2

From the Research

Management of Chronic Kidney Disease Stage 3b

• The patient's condition is complex, involving chronic kidney disease stage 3b, osteopenia, and a history of fractures 3.
• Managing osteoporosis in patients with chronic kidney disease is challenging due to the complexity of bone disorders in this population 3, 4.

Treatment of Osteoporosis

• Antiresorptive and osteoanabolic agents approved for osteoporosis are being used off-label to treat CKD stages 3b-5 in high-risk patients 3.
• Intermittent administration of parathyroid hormone as early as CKD stage 2 could be an effective management strategy, but more research is needed 3.

Vitamin D Supplementation

• Vitamin D deficiency is common in patients with CKD, and supplementation should be prescribed early in the course of renal disease 4, 5.
• Cholecalciferol 800 IU/day or the equivalent per month is recommended for treatment and prevention of vitamin D deficiency in CKD patients 4.

Alternative Supplements

• Vitamin K deficiency is also common in CKD patients, and combined supplementation of vitamins K and D may be beneficial for bone health 6.
• However, there is no consensus on the optimal levels of vitamins K and D in CKD patients, and more research is needed to determine the best supplementation strategy 6.

Management of Constipation

• The patient's constipation with calcium supplements may require alternative treatments, but there is no specific guidance in the provided studies.
• It is essential to consider the patient's overall health and medical history when managing constipation and other symptoms 7.

Clinical Practice Guidelines

• The European Renal Best Practice Group has published guidelines on the management of older patients with CKD stage 3b or higher, which may be helpful in informing treatment decisions 7.