Total body bone mineral density and various spinal disorders: a Mendelian randomization study

Area of Science:

• Genetics
• Orthopedics
• Epidemiology

Background:

• Observational studies show inconsistent links between bone mineral density (BMD) and spinal disorders.
• Further investigation is needed to clarify the relationship between total-body BMD and spinal conditions.

Purpose of the Study:

• To assess the association between total-body BMD and various spinal disorders using Mendelian randomization (MR).

Main Methods:

• A two-sample bidirectional MR analysis was conducted.
• The inverse-variance weighted (IVW) method was primary, with sensitivity analyses using weighted median, MR-Egger, and other methods.
• Robustness was checked using alternative bone density databases and outcome data validation.

Main Results:

• MR analysis revealed a significant positive association between total-body BMD and spondylosis and spinal stenosis.
• Increased risk of spinal stenosis (OR 1.23) and spondylosis (OR 1.24) was observed with higher total-body BMD.
• Heel BMD also positively correlated with spinal stenosis (OR 1.13) and spondylosis (OR 1.10).
• No significant associations were found with spinal instability, spondylolisthesis/spondylolysis, or scoliosis.

Conclusions:

• This study confirms an association between total-body BMD and spinal stenosis and spondylosis.
• Increased BMD may indicate a higher risk for these conditions, warranting investigation in patients with relevant symptoms.