Major outcomes from PEEDS strengthen the evidence for multilevel deformity spinal surgery in older adults

We are delighted to announce the primary outcome from AO Spine Knowledge Forum Deformity’s Prospective Evaluation of Elderly Deformity Surgery (PEEDS) study. It provides high-quality prospective, international data that surgeons can use when counselling older patients and their families about what to expect following long segment spinal fusion surgery.

Adult spinal deformity (ASD) in patients over 60 is one of the fastest growing spine practices and involves complex reconstructions with associated risk. They can also considerably improve a patient’s function, independence, and quality of life.

PEEDS is a global, prospective, observational, multicenter effort with long-term follow-ups at 2 and 5 years, designed to quantify both the benefits and the burden of multilevel deformity correction in older adults. The study is led by Principal Investigator Stephen J. Lewis and Co–Principal Investigator Sigurd H. Berven.

“PEEDS was designed to bring clarity to one of the hardest conversations we have in clinic, and how to balance meaningful, durable improvement against the realistic risk profile of multilevel spinal reconstruction in older adults,” Lewis explained.

Reliable data for realistic expectations

“What we aim to do, is give patients and surgeons dependable data for informed decision making on whether to operate. We provide objective data on what improves, how much it improves,  when it improves, what risks are most common, and how long the benefits last,” said Lewis.

The recent publication on the primary outcomes of PEEDS, now online in Global Spine Journal, follows patients aged 60 years and older undergoing ≥5-level spinal fusion surgery across 12 international centers, with outcomes tracked out to five years. In a cohort of 219 eligible patients (mean age 67.5, range 60–83; 80.4% female), the study demonstrated statistically significant and clinically meaningful improvements in patient-reported outcomes that were maximal at one year and maintained through two and five years. Specifically, the mean change in SRS-22r subtotal and total scores from baseline to five years was 0.88 and 0.90, respectively (both P < .001), with similar durable improvement patterns reported for Oswestry Disability Index, numeric rating scales pain assessment, and EQ-5D.

Just as importantly for informed consent and expectation setting, PEEDS reports adverse events so that surgeons can translate the data into their conversations with patients. Over the first two years, the cohort experienced 244 adverse events in 124 patients, with an additional 25 adverse events in 20 patients between years two and five.

The key message is that, even in a population with substantial baseline disability and comorbidity, meaningful and durable improvements are achievable despite a relatively high adverse event rate. This is the reality spine surgeons already understand anecdotally, but now they can support it with prospective, multicenter evidence.

Detailed analysis supports patient-centered decision making

Several earlier companion papers from PEEDS add detailed knowledge to day-to-day decision-making. In The Spine Journal, PEEDS investigators previously showed how outcomes vary when stratified by baseline ODI, providing a patient-centered way to frame likely improvement. In this retrospective analysis of the prospective, multicenter, multicontinental cohort, nearly 70% of patients reported significant improvement in ODI at two years, and the proportion categorized as “severely disabled” (ODI > 40%) dropped from 59.0% preoperatively to 20.2% at two years.

Notably, the greatest item-level improvements included pain and key real-world activities such as walking, standing, social life, and traveling. These are the domains older patients tend to prioritize when they say, “I just want my life back.”

In Global Spine Journal, an ancillary PEEDS analysis focused on EQ–5D and residential status, outcomes that resonate strongly with older adults and their caregivers. Patients improved from an EQ-5D index of 0.53 preoperatively to 0.73 at 24 months, and the authors calculated an MCID of 0.22 for EQ-5D at one year in this population. Residential status tells a similarly concrete story: while home living dipped early (10 weeks), by 24 months 100% of patients with available data were living at home, reinforcing the idea that temporary postoperative vulnerability does not necessarily translate into long-term loss of independence.

Most recently, another PEEDS paper published in the Global Spine Journal asked a question many surgeons struggle to answer in clinic: “Will my social function actually improve?” In older patients, social engagement is often restricted not only by pain but also by stamina, confidence, balance, fear of falling, and the logistics of leaving home. The PEEDS social function analysis reported significant improvement in SRS-22r social function at one, two, and five years, again with the strongest gains at one year and durability at longer follow-up.

Prognostic factors for function, quality of life, and independence

One of the most interesting clinical insights across PEEDS is identifying predictors of outcome in this cohort, published in the Global Spine Journal. In the PEEDS prognostic analysis evaluating who achieves MCID for SRS-22r and EQ-5D, the most consistent predictors were baseline health status and the occurrence or severity of adverse events. While surgical, clinical, or radiographic variables were not identified as independent prognostic factors across the tested approaches.

Further work on the expected functional outcomes of patients on 5 key functions that included walking, standing, sitting, social function and personal care confirmed the benefits of multilevel spinal fusion surgery in the PEEDS cohort. Improvements in these 5 core functions improved substantially even in the most disabled patients where 83% showed significant improvements. Interestingly, baseline function reflected final outcome with only 27% of severely disabled patients at baseline reaching the highest level of function at 2 years compared to 89% in the patients with the highest level of baseline function. This analysis is discussed in The Spine Journal.

Put differently, patient selection and perioperative risk management play significant roles in achieving meaningful benefit and were more impactful than any single radiographic target or technique variable. For surgeons, this highlights the importance of optimizing baseline health, planning for complication avoidance, and building postoperative pathways that reduce the impact of adverse events when they occur.

Opioid-history associated with back pain

Another clinically important signal from the AO Spine Knowledge Forum Deformity evidence base is the impact of preoperative opioid use on both pain outcomes and postoperative opioid requirements. The analysis published in Global Spine Journal—which also stemmed from the PEEDS study—found that opioid use in older adult deformity patients prior to deformity correction surgery was strongly associated with worse baseline back pain that persisted at two-year follow-up, along with prolonged opioid demands after surgery.

The findings reinforce what surgeons see in clinic, that opioid exposure can shape the recovery trajectory and the durability of pain relief. These data support incorporating opioid history into shared decision-making and strengthen the rationale for preoperative optimization pathways (including opioid weaning where feasible) as part of comprehensive care for elderly deformity patients.

From knowledge to action

The findings from PEEDS are published as the AO Foundation and the AO Spine Knowledge Forums are putting increased focus into accelerating the translation of knowledge into practice. PEEDS findings provide actionable knowledge, with a clear purpose of improving patient outcomes with its practical adoption.

For practicing deformity surgeons, PEEDS provides prospective, international, longer-term data to support transparent counselling on both expected improvement and expected risk. It will help define success around outcomes that are most important to older patients, on function, quality of life, and independence.