Performance of models for predicting 1-year to 3-year mortality in older adults: a systematic review of externally validated models

Mortality prediction models support identifying older adults with short life expectancy for whom clinical care might need modifications. We systematically reviewed external validations of mortality prediction models in older adults (ie, aged 65 years and older) with up to 3 years of follow-up. In March, 2023, we conducted a literature search resulting in 36 studies reporting 74 validations of 64 unique models. Model applicability was fair but validation risk of bias was mostly high, with 50 (68%) of 74 validations not reporting calibration. Morbidities (most commonly cardiovascular diseases) were used as predictors by 45 (70%) of 64 of models. For 1-year prediction, 31 (67%) of 46 models had acceptable discrimination, but only one had excellent performance. Models with more than 20 predictors were more likely to have acceptable discrimination (risk ratio [RR] vs <10 predictors 1.68, 95% CI 1.06-2.66), as were models including sex (RR 1.75, 95% CI 1.12-2.73) or predicting risk during comprehensive geriatric assessment (RR 1.86, 95% CI 1.12-3.07). Development and validation of better-performing mortality prediction models in older people are needed.