By 0.6 days, in the one study that measured it. That cohort also billed about $10,400 less for the operation itself [1]. The saving does not survive arithmetic, and the stay is the smaller half of the story. Complications did not move in any of the three studies below. How drug spending compares with surgical spending is set out in who pays for what.
The lumbar fusion cost figures
A claims analysis matched 425 semaglutide users against 2,514 controls. All had anterior lumbar interbody fusion between 2010 and 2022. Users stayed 0.6 days less. Same-day surgical costs ran about $10,400 lower and 90-day costs about $9,700 lower.
The threshold was strict. Bonferroni adjustment put it at P < .003, which is tighter than most claims work manages. Complication rates did not differ at 90 days or two years.
One route would make the saving real. An anterior approach through less abdominal tissue is faster and may need less hardware. If that is what happened, the saving follows the weight rather than the drug. That distinction matters to anybody pricing a prescription.
The stay, measured again in a larger sample
A second analysis started from 136,571 nondiabetic patients having posterior cervical spine surgery [2]. It matched 1,719 GLP-1 users to 1,719 non-users. Emergency department visits within 90 days came in at an odds ratio of 0.71, 95% CI 0.58 to 0.87. Hospital admission ran 0.54, 95% CI 0.41 to 0.70.
Nothing else moved. No difference in surgical or medical complications at 90 days. No difference at two years in mortality, revision, surgical site infection or deep infection. The perioperative worry about these drugs is covered in the pre-procedure hold.
The hip fracture figures, and why they cannot be a drug effect
A single institution studied 58 obese hip fracture patients on at least six months of GLP-1 therapy [3]. They were matched against three control groups of 58. Overall complications were 22.41% against 55.17% in normal-weight controls. Overweight controls ran 51.72% and obese non-users 60.34%.
Obesity raises complication risk after a hip fracture. A treated obese group beating normal-weight patients by thirty-three points is not a mechanism. It is the signature of a group healthy enough to have been on elective maintenance therapy for six months. Major complications, hardware failure, and 30-day and one-year outcomes all showed no difference. The related fracture question sits in what these drugs do to bone.
What a buyer can use
The nulls. Three samples, three procedures, and no signal that these drugs make surgery go worse. That is worth knowing given how much perioperative caution circulates.
The cost figures are weaker than they look. Amounts in claims data are billed or reimbursed sums. In US healthcare, billed, spent and paid routinely differ by multiples. A $10,400 reduction in a claims field is not $10,400 in anybody’s pocket. That is the same gap described in headline against bill and in whose money is saved.