Outpatient versus inpatient lumbar decompression surgery: a matched noninferiority study investigating clinical and patient-reported outcomes

OBJECTIVE

Spine surgery represents an ideal target for healthcare cost reduction efforts, with outpatient surgery resulting in significant cost savings. With an increased focus on value-based healthcare delivery, lumbar decompression surgery has been increasingly performed in the outpatient setting when appropriate. The aim of this study was to compare clinical and patient-reported outcomes following outpatient and inpatient lumbar decompression surgery.

METHODS

The Quality Outcomes Database (QOD) was queried for patients undergoing elective one- or two-level lumbar decompression (laminectomy or laminotomy with or without discectomy) for degenerative spine disease. Patients were grouped as outpatient if they had a length of stay (LOS) < 24 hours and as inpatient if they stayed in the hospital ≥ 24 hours. Patients with ≥ 72-hour stay were excluded from the comparative analysis to increase baseline comparability between the two groups. To create two highly homogeneous groups, optimal matching was performed at a 1:1 ratio between the two groups on 38 baseline variables, including demographics, comorbidities, symptoms, patient-reported scores, indications, and operative details. Outcomes of interest were readmissions and reoperations at 30 days and 3 months after surgery, overall satisfaction, and decrease in Oswestry Disability Index (ODI), back pain, and leg pain at 3 months after surgery. Satisfaction was defined as a score of 1 or 2 in the North American Spine Society patient satisfaction index. Noninferiority of outpatient compared with inpatient surgery was defined as risk difference of < 1.5% at a one-sided 97.5% confidence interval.

RESULTS

A total of 18,689 eligible one- and two-level decompression surgeries were identified. The matched study cohorts consisted of 5016 patients in each group. Nonroutine discharge was slightly less common in the outpatient group (0.6% vs 0.3%, p = 0.01). The 30-day readmission rates were 4.4% and 4.3% for the outpatient and inpatient groups, respectively, while the 30-day reoperation rates were 1.4% and 1.5%. The 3-month readmission rates were 6.3% for both groups, and the 3-month reoperation rates were 3.1% for the outpatient cases and 2.9% for the inpatient cases. Overall satisfaction at 3 months was 88.8% for the outpatient group and 88.4% for the inpatient group. Noninferiority of outpatient surgery was documented for readmissions, reoperations, and patient-reported satisfaction from surgery.

CONCLUSIONS

Outpatient lumbar decompression surgery demonstrated slightly lower nonroutine discharge rates in comparison with inpatient surgery. Noninferiority in clinical outcomes at 30 days and 3 months after surgery was documented for outpatient compared with inpatient decompression surgery. Additionally, outpatient decompression surgery performed noninferiorly to inpatient surgery in achieving patient satisfaction from surgery.

Noninferiority of perphenazine vs. three second-generation antipsychotics in chronic schizophrenia

Noninferiority analysis is a statistical method of growing importance in comparative effectiveness research that has rarely been used in psychopharmacology. This method is used here to evaluate whether first-generation antipsychotics are clinically not inferior to second-generation antipsychotics (SGAs) using data from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE). A conservative noninferiority margin (NIM) on the Positive and Negative Syndrome Scale (PANSS) was derived from the smallest published value for the minimal clinically important difference, further reduced by 25%. This NIM was used to assess whether perphenazine is noninferior to olanzapine, risperidone, and quetiapine on the basis of the 95% confidence intervals of differences in mean PANSS outcomes (N = 1049). Perphenazine was noninferior to all three SGAs during 18 months of intention-to-treat analysis and in several subanalyses. Noninferiority can be evaluated from studies designed as superiority trials. Power was available in the CATIE to conduct noninferiority analysis.