The Relationship Between Body Composition and Bone Quality Measured with HR-pQCT in Peritoneal Dialysis Patients

Interaction Effect of Phase Angle and Age on Femoral Neck Bone Mineral Density in Patients with Non-Dialysis Chronic Kidney Disease Stage 5

Background: Low bone mass is common in malnourished patients with chronic kidney disease (CKD) and can lead to a higher risk of fractures. Elderly and CKD patients have the same risk factors for protein-energy wasting, sarcopenia, and osteoporosis. Here, we investigated the association between phase angle (PhA) and bone mineral density (BMD) in dialysis-naïve patients with CKD stage 5 (CKD5) and identified a statistical relationship between PhA and age, which affects bone density. Methods: Bio-impedance spectroscopy for evaluating body composition and PhA and dual-energy X-ray absorptiometry for determining the BMD were simultaneously performed in 167 consecutive patients (mean age, 59.65 ± 13.98 years; women, 40.1%). Two-way analysis of variance (ANOVA) was conducted to assess the potential interaction effect of PhA and age on femoral neck BMD (FN-BMD). Results: Our results showed that PhA and age were independently associated with FN-BMD and T-score in multiple linear regressions analyses. A significant interaction effect of PhA and age on FN-BMD was found on two-way ANOVA (p = 0.028). The average BMD values for the first and second tertiles of the PhA were higher in the young versus elderly group, whereas patients in the elderly group had higher BMD in the third tertiles. Conclusions: A relationship was noted between PhA and BMD in patients with advanced-stage CKD. The effect of PhA level on FN-BMD differed between elderly and young patients. Our study suggested that higher PhA levels could be a marker explaining the maintenance of good bone health in elderly patients with CKD5. Further longitudinal analyses are needed to determine whether PhA predicts the risk of CKD-MBD-related fractures during CKD progression.

"Sarcopenia and risk of osteoporosis, falls and bone fractures in patients with chronic kidney disease: A systematic review"

Background

Chronic kidney disease [CKD] has been suggested to increase the risk of osteoporosis, sarcopenia, falls, and fractures. The aim of this systematic review was to explore the occurrence of osteoporosis, falls, and fractures in patients with sarcopenia and CKD, and to explore the possible association between sarcopenia and osteoporosis, falls, and fractures in patients with CKD.

Methods

This systematic review was conducted according to the PRISMA guideline. The protocol was registered at PROSPERO. The systematic literature search was conducted in Pubmed [1966 to present] and EMBASE [1974 to present] on December 4, 2020. We searched for articles on CKD and sarcopenia, and then we selected them with outcomes such as osteoporosis, falls, and bone fractures. The risk of bias was assessed with the Newcastle-Ottawa Scale.

Results

Five studies were eligible and included. No studies reported the occurrence of osteoporosis, falls, and bone fractures in patients with CKD and sarcopenia. Sarcopenia had a significant association with low bone mineral density [BMD] and osteoporosis in patients with CKD. The risk of bias assessed with the Newcastle-Ottawa Scale varied from 3–7 stars [median of 7]. Due to the included studies’ heterogeneity, a meta-analysis could not be conducted.

Conclusion

The occurrence of osteoporosis, falls, and bone fractures in patients with sarcopenia and CKD could not be assessed from the included studies, but an association between sarcopenia and decreased BMD/osteoporosis in patients with CKD was found. The potential mechanistic link between sarcopenia and osteoporosis in CKD needs to be investigated in future studies.

Bone Quality in Chronic Kidney Disease Patients: Current Concepts and Future Directions - Part II

Background

Patients with chronic kidney disease (CKD) have an increased risk of osteoporotic fractures, which is due not only to low bone volume and mass but also poor microarchitecture and tissue quality. The pharmacological and nonpharmacological interventions detailed, herein, are potential approaches to improve bone health in CKD patients. Various medications build up bone mass but also affect bone tissue quality. Antiresorptive therapies strikingly reduce bone turnover; however, they can impair bone mineralization and negatively affect the ability to repair bone microdamage and cause an increase in bone brittleness. On the other hand, some osteoporosis therapies may cause a redistribution of bone structure that may improve bone strength without noticeable effect on BMD. This may explain why some drugs can affect fracture risk disproportionately to changes in BMD.

Summary

An accurate detection of the underlying bone abnormalities in CKD patients, including bone quantity and quality abnormalities, helps in institution of appropriate management strategies. Here in this part II, we are focusing on advancements in bone therapeutics that are anticipated to improve bone health and decrease mortality in CKD patients.

Key Messages

Therapeutic interventions to improve bone health can potentially advance life span. Emphasis should be given to the impact of various therapeutic interventions on bone quality.