Differences in clinical outcomes and health care utilization between octogenarians and nonagenarians following decompression for lumbar spinal stenosis. A market scan analysis.

Abstract Objective Lumbar spinal stenosis (LSS) in octogenarians and beyond has a significant impact on quality of life requiring surgical decompression and hence impact on health care utilization. Risk of surgical failure and impact on health care resources is always a concern in this patient population (more so in nonagenarians). The aim of our study was to compare clinical outcomes and healthcare utilization in patients (80–89 vs.90+) undergoing decompression for LSS. Patients and methods Data was extracted using ICD9/10 and CPT codes from MarketScan (2001–2015) in this retrospective study. We defined the comparative groups based on the age groups (80–89 and 90+), in patients with LSS. Outcomes of interest were: length of hospital stay, discharge disposition and utilization in the index hospitalization, 6- months, 12 months following index procedure as well as the associated health care utilization. Patient characteristics and outcomes among cohorts were compared using univariate tests. Outcomes were further compared using adjusted multivariable regression models. Statistical analysis was performed with SAS 9.4. Results A cohort of 5387 was identified from the database, 96.38% were in the 80–89 age group and 3.62%were in the 90+ age group. The proportion of patients undergoing surgery for LSS among 80–89 (95.7–98.5%) and 90+ age group (1.5–4.3%) remained constant through the years. Interestingly, 13.83% and 16.92% of patients had Elixhauser comorbidity index of 3+ in 80–89 age group and 90+ age groups respectively. Decompression with fusion was performed in 19.4% of patients in 80–89 age group, compared to 9.74% of patients in 90+ age group. There was no difference in median length of hospital stay (3 days, p = 0.19) and complications across the cohorts (80–89: 16.7%; 90+: 18.46% p = 0.51). 70.6% of patients in 80–89 age groups were discharged to home compared to 60.5% in 90+ age group (p = 0.0023). At 6 months follow-up, overall rate of new decompression, new fusion, re-fusion at index level were 2.38%, 0.59% and 0.33% only, with no differences across the cohorts. Interestingly, patients in 80–89 age group incurred higher outpatient services, number of medication refills and related payments at 6-months and 12-months follow-up, compared to patients in 90+ age group. Overall, combined median post-discharge payments at 12 months were similar across the groups [80–89 (median $ 40,257) and 90+ (median$ 36,161), p = 0.14]. Conclusion Using MarketScan database, there has been a gradual decline in the number of decompressions being performed for LSS in elderly patients (>80 years of age), however there is no change in the proportion of octogenarians and nonagenarians undergoing decompression for LSS. There was no difference in rate of reoperations and overall health care utilization among the groups. Surgery for LSS can be offered to nonagenarians (in appropriately selected patients) with no difference in clinical outcomes and health care utilization, compared to octogenarians.