History of spine surgery in older obese patients

Goal: To study the interaction of obesity and age in patients with multiple spine surgeries. Methods: Data on the body mass index (BMI) of 956 patients were collected and classified into four groups: non-obese (BMI <30 kg/m(2)), obese-class I (BMI ≥30 kg/m(2)), obese-class II (BMI ≥35 kg/m(2)) and obese-class III (BMI ≥40 kg/m(2)). Patients' age was categorized into the following age groups: ≤40, 41–65 and ≥66. T-test and Chi-square test were applied using SPSS v16. Results: In lumbar patients aged ≥66 years with previous spine surgery, the average number of previous spine surgeries significantly increased with increasing obesity from 1.4 in nonobese patients to 1.7, 2.5 and 3.5 in obese class I, II and III patients. In lumbar decompression and fusion patients aged ≥66 years with previous spine surgery, the average number of previous spine surgeries signifi-cantly increased with increasing obesity from 1.7 in nonobese patients to 1.6, 2.0 and 3.5 in obese class I, II and III patients. A similar trend was noted in lumbar microdiskectomy patients aged ≥66 years but it was statistically nonsignificant due probably to small numbers. Conclusion: Obesity is associated with an increased number of previous spine surgeries in patients over 65 years of age undergoing lumbar surgery.