A prognostic model predicted deterioration in health-related quality of life in older patients with multimorbidity and polypharmacy.

Abstract Objective To develop and validate a prognostic model to predict deterioration in health-related quality of life (dHRQoL) in older general practice patients with at least one chronic condition and one chronic prescription. Study design and setting We used individual participant data from five cluster-randomized trials conducted in the Netherlands and Germany to predict dHRQoL, defined as a decrease in EQ-5D-3L index score of ≥ 5 % after six-month follow-up in logistic regression models with stratified intercepts to account for between-study heterogeneity. The model was validated internally, and by using internal-external cross-validation (IECV). Results – In 3,582 patients with complete data, of whom 1,046 (29.2 %) showed deterioration in HRQoL, 12/87 variables were selected that were related to single (chronic) conditions, inappropriate medication, medication underuse, functional status, well-being and HRQoL. Bootstrap internal validation showed a C-statistic of 0.71 (0.69 to 0.72), and a calibration slope of 0.88 (0.78 to 0.98). In the IECV loop, the model provided a pooled C-statistic of 0.68 (0.65 to 0.70) and calibration-in-the-large of 0 (-0.13 to 0.13). HRQoL/functionality had the strongest prognostic value. Conclusion – The model performed well in terms of discrimination, calibration, and generalizability and might help clinicians identify older patients at high-risk of dHRQoL. Registration PROSPERO ID: CRD42018088129