Background

Older patients are vulnerable to developing new or worsening disability after surgery. Despite this, patient or surgical characteristics predisposing to postoperative disability are poorly defined. Our aim was to develop and validate a model, subsequently transformed to point-score form, to predict 6-month death or disability in older patients after surgery.

Methods

The authors built a prospective, single-center registry to develop and validate the prediction model. The registry included patients 70 years of age or older undergoing elective and non-elective, cardiac and non-cardiac surgery between 25 May 2017 to 11 February 2021, and combined clinical data from the electronic medical record, hospital administrative data (ICD-10 AM codes) and World Health Organization Disability Assessment Schedule (WHODAS) data collected directly from the patients. Death or disability was defined as being dead or having a WHODAS score ≥16%. Included patients were randomly divided into model development (70%) and internal validation (30%) cohorts. Once constructed, the logistic regression and point-score models were assessed using the internal validation cohort and an external validation cohort comprising data from a separate randomized trial.

Results

Of 2176 patients who completed the WHODAS immediately prior to surgery, 927 (43%) patients were disabled and 413 (19%) had significant disability. By 6 months after surgery, 1640 patients (75%) had data available for the primary outcome analysis. Of these patients 195 (12%) patients had died and 691 (42%) were dead or disabled.

The developed point-score model included the preoperative WHODAS score, patient age, dementia, and chronic kidney disease. The point score model retained good discrimination in the internal (area under the curve 0.74, 95% CI 0.69 to 0.79) and external (area under the curve 0.77, 95% CI 0.74, 0.80) validation data sets.

Conclusions

We developed and validated a point score model to predict death or disability in older patients after surgery.