Outcome Differences Between General and Neuraxial Anesthesia for Hip Fracture by Frailty and Age in the Elderly: A Retrospective Cohort Study

Citation:

Giannakis P, Restrepo M, Stone AB, Zhuang ST, Wang J, Cozowicz C, et al. Outcome Differences Between General and Neuraxial Anesthesia for Hip Fracture by Frailty and Age in the Elderly: A Retrospective Cohort Study. Anesth Analg. 2026;XXX(00):00–300. doi:10.1213/ANE.0000000000008062

Using a large United States hospital claims database, Giannakis and colleagues compared neuraxial versus general anesthesia for more than six hundred thousand hip fracture surgeries across age and frailty strata. Neuraxial anesthesia was associated with very small differences in in-hospital mortality and a composite of major complications, a clearer reduction in high opioid use, and slightly more discharges home, but also small increases in some complications and intensive care admissions. Because anesthesia type was not randomized and key clinical confounders and outcomes were captured only through billing codes, overall certainty is very low and the results should inform, not dictate, anesthetic choice.

Study at a glance

- Design and setting: Retrospective cohort study using the Premier Healthcare Database, including 623,122 adults undergoing surgical treatment of hip fracture in United States hospitals between 2016 and 2023. Exposure was anesthesia type (general vs neuraxial) coded from billing data; outcomes (in-hospital mortality, major complications, intensive care unit admission, length of stay, opioid use, discharge disposition) were defined from ICD-10-CM diagnosis codes and billing records. Associations were estimated with mixed-effects multivariable logistic regression adjusted for demographics, comorbidities, hospital characteristics, procedure type, peripheral nerve block use, fracture type, and time to surgery.

- Primary outcome – composite of death and major complications: The prespecified primary endpoint was a composite of in-hospital mortality, respiratory complications, cardiac complications, acute renal failure, and delirium. Overall, neuraxial anesthesia versus general anesthesia was associated with an adjusted odds ratio (OR) of 0.97 (95% confidence interval [CI] 0.94–0.997; p=0.053), a very small relative difference compatible with little to no effect. Given the nonrandomized, claims-based design and serious residual confounding, GRADE certainty for this outcome is Very Low; the apparent benefit could easily be due to unmeasured differences between patients selected for each technique.

- In-hospital mortality: In-hospital death was lower in the neuraxial group overall, with an adjusted OR of 0.83 (95% CI 0.74–0.93; p=0.003), and a more pronounced association in older, more frail subgroups (for example, OR 0.77, 95% CI 0.65–0.91 in patients aged ≥87 years with intermediate/high frailty). However, choice of anesthesia is strongly confounded by clinical status, cognitive function, and hemodynamic reserve, which are incompletely measured in claims. With Serious overall risk of bias and no advanced causal methods, GRADE certainty for any mortality benefit is Very Low.

- Key secondary outcomes – opioid use, discharge home, length of stay: Neuraxial anesthesia was associated with a moderate reduction in high postoperative opioid use (overall adjusted OR 0.69, 95% CI 0.66–0.72; p<0.001), consistent across age and frailty strata, and with slightly higher odds of discharge to home among survivors (overall OR 1.08, 95% CI 1.04–1.12; p<0.001). Prolonged length of stay (≥75th percentile) showed a very small reduction with neuraxial anesthesia (overall OR 0.97, 95% CI 0.94–0.998; p=0.046). High opioid use is a process measure rather than a direct patient-important endpoint, and discharge disposition and length of stay are influenced by social and system factors; all three outcomes are rated Very Low certainty due to serious confounding and, for opioid use, additional indirectness.

- Potential harms – respiratory, cardiac, and ICU outcomes: Across the overall cohort, neuraxial anesthesia was associated with slightly higher rates of several coded complications and intensive care unit use: respiratory complications (OR 1.06, 95% CI 1.01–1.10; p=0.03), cardiac complications (OR 1.07, 95% CI 1.02–1.12; p=0.008), and intensive care unit admission (OR 1.07, 95% CI 1.03–1.12; p=0.002). Subgroup and sensitivity analyses showed some heterogeneity by age, frailty, and hospital neuraxial use, but effects remained small. Because these outcomes rely on diagnosis codes without validation and are highly susceptible to confounding by severity and practice patterns, GRADE certainty is Very Low, and the direction of true effect is uncertain.

- Risk of bias, certainty, and practice implications: Overall risk of bias is judged Serious due to residual confounding by indication, selection related to coding completeness, and outcome misclassification from claims data. All appraised outcomes, including the primary composite, mortality, complications, length of stay, opioid use, intensive care unit admission, and discharge home, are rated Very Low certainty with GRADE. Clinically, the study suggests that neuraxial and general anesthesia for hip fracture have broadly similar in-hospital risks, with neuraxial associated with less high opioid use and more home discharges but also small increases in some complications, all very uncertain. These findings should not, on their own, drive a major practice shift; instead, anesthetic choice should remain individualized, and system-level improvements in timely surgery, hemodynamic management, multimodal analgesia, delirium prevention, and early mobilization are likely to have larger and more reliable impact than anesthesia type alone.