Bone Metabolism Disorders, Chronic Kidney Disease (Stage 3-4), Mineral and Bone Disorder (CKD-MBD), Osteopenia
Conditions
Keywords
Chronic kidney disease, RANKL, OPG/RANKL Ratio, Osteoprotegerin, Aerobic Exercise, Resistance Exercise, Bone mineral density
Brief summary
This randomized controlled trial investigates the comparative effects of aerobic versus resistance training on bone mineral density (BMD) and bone metabolism markers in patients with stage 3 or 4 chronic kidney disease (CKD). The primary aim is to evaluate the impact of two distinct exercise modalities on serum osteoprotegerin (OPG), receptor activator of nuclear factor kappa-B ligand (RANKL), and the OPG/RANKL ratio, as well as densitometric changes at key skeletal sites.
Detailed description
Chronic kidney disease-mineral and bone disorder (CKD-MBD) is a common complication in non-dialysis CKD patients, driven by disrupted calcium-phosphate metabolism, secondary hyperparathyroidism, and altered bone remodeling pathways, such as the OPG-RANKL axis. Exercise is an emerging non-pharmacological strategy to mitigate skeletal deterioration in CKD, yet the differential effects of aerobic and resistance training on bone health remain poorly understood in this population. This study recruited 60 CKD patients (stage 3-4, aged 30-50 years) and randomly allocated them into two groups (n=30 each): a resistance training group and an aerobic exercise group. Both groups underwent supervised exercise 3 times per week for six months. Bone mineral density was assessed using dual-energy X-ray absorptiometry (DEXA) at the lumbar spine (L2-L4), femoral neck, and distal radius. Serum concentrations of OPG and RANKL were measured via ELISA at baseline and post-intervention.
Interventions
BEHAVIORALResistance Exercise
Structured machine-based resistance exercise protocol performed under supervision, targeting osteogenic loading to improve bone mineral density and alter bone metabolism markers in CKD stage 3-4 patients.
BEHAVIORALAerobic Training
Participants in this arm performed supervised aerobic exercise (treadmill walking) three times per week for six months. Each session included: 5-minute warm-up 30-minute treadmill walking at 60%-80% of age-predicted maximum heart rate (HRmax = 220 - age) 10-minute cool-down Exercise sessions were supervised by trained exercise professionals and tailored to maintain target heart rate zones.
Sponsors
Sinai University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)
Masking description
None (Open Label)
Intervention model description
Interventional (Clinical Trial)
Eligibility
Sex/Gender
ALL
Age
30 Years to 50 Years
Healthy volunteers
No
Inclusion criteria
* Adults aged 30 to 50 years * Diagnosed with stage 3 or 4 chronic kidney disease (non-dialysis dependent) * BMI between 20 and 24 kg/m² * Not currently taking medications that affect bone density (e.g., corticosteroids, bisphosphonates) * Non-smokers and abstinent from alcohol * Not receiving hormone replacement therapy * Willing and able to participate in supervised exercise sessions for 6 months
Exclusion criteria
* Diagnosis of type 1 diabetes mellitus * Uncontrolled hypertension * History of cardiovascular, musculoskeletal, endocrine, or metabolic bone disease * Pregnant or planning pregnancy during the study period * Participation in a structured exercise program within the last 3 months * Contraindications to exercise as determined by medical evaluation * Use of investigational drugs or enrollment in another clinical trial during the study period
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Serum Osteoprotegerin (OPG) and RANKL Concentrations | Baseline to 6 months post-intervention | To determine biochemical changes in bone metabolism markers. Both OPG (pg/mL) and RANKL (ng/mL) are measured using validated ELISA kits. |
| Change in Bone Mineral Density (BMD) | Baseline to 6 months post-intervention | To assess densitometric changes in skeletal structure due to exercise. BMD is measured in g/cm² using ISCD-certified DEXA equipment. |
| Change in OPG/RANKL Ratio | To assess the regulatory balance of bone remodeling. A higher OPG/RANKL ratio reflects reduced osteoclastic activity and improved bone metabolic status. | Baseline to 6 months post-intervention |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in eGFR (estimated Glomerular Filtration Rate) | Baseline to 6 months | To explore the potential renal benefits of structured exercise in CKD patients. Measured in mL/min/1.73 m². |
| Change in Serum Albumin and Hemoglobin Levels | Baseline to 6 months | These indicators provide information about overall nutritional and hematologic status. Albumin (g/dL) and Hemoglobin (g/dL) are assessed via standard lab procedures. |
Countries
Egypt
Outcome results
None listed