Changes in the glycosylated hemoglobin levels and body mass index after decompression surgery in patients with lumbar spinal stenosis in a tertiary care center, Saudi Arabia

Objectives: Lumbar spinal decompression surgery is a well-studied intervention in its benefit in pain control. It can also improve physical activity that indirectly facilitates glycemic control in diabetic patients and weight loss in obese patients. This study aimed to assess the changes of glycosylated hemoglobin (HbA1c) and body mass index (BMI) in patients with lumbar spinal stenosis (LSS) post-intervention at 6- and 12-month follow-ups. Methods: This was a retrospective cohort study of patients with LSS who had lumbar decompression, with or without instrumentation at King Abdulaziz Medical City, from 2016 and 2020. Patients over 18 years, treated surgically for LSS, were included with a minimum of a 1-year follow-up. Patients with Type 1 diabetes mellitus, with comorbidities, that limited physical activity, or without follow-up records were excluded from the study. Results: In total, 140 patients were included in the study. They had three underlying diseases: LSS ( n = 87, 62.1%), spondylolisthesis ( n = 37, 26.4%), and degenerative disc disease ( n = 16, 11.4%). Results showed that obese patients were associated with the lower BMI at 6- and 12- month follow-ups compared to the non-obese. In addition, there was a statistical difference in HbA1c change at follow-ups between controlled (HbA1c <7) and uncontrolled diabetes groups (HbA1c ≥7). Conclusion: Lumbar spinal decompression can help in the reduction of BMI of obese patients with LSS. However, there is a need for extensive investigation of the reasons for the contradicting results of an increase in the HbA1c level at 12-month follow-up in the current study.