Use of the MMPI-2 personality profile in predicting 30-day ED-visits and readmissions following primary bariatric surgery

Background: Minnesota Multiphasic Personality Inventory-2 (MMPI-2) is used for psychological screening of bariatric surgery (BS) candidates. To date, no studies have analyzed the relationship between MMPI-2 and early returns to hospital. The aim of this study was to determine whether high T scores on the MMPI-2 clinical scales were associated with early return to hospital after primary bariatric surgery.

Methods: Patients who completed an MMPI-2 evaluation, undergoing primary BS from 2014 to 2016 were evaluated. T score for the tested scales were collected and stratified into a high T score (T > 65) vs not (T < 65). The optimal 'cut-point' (specific number of high T scores predicting likelihood for 30-day ED-visit/hospital readmission) was calculated using Youden's Index (J) = Max(c) [sensitivity (c) + specificity (c) - 1], where c = number of scales with a T score > 65. Patients were stratified based on the optimal cut-point which was determined to be ≥ 4 high T scores. Univariate and multivariate logistic regression analyses were used to identify differences between groups and predictors for early ED-visits and hospital readmissions.

Results: 375 patients had psychological evaluations available for review. Patients were divided into those with ≥ 4 high T scores (Scr_(≥4); n = 86) versus not (Scr _(<4); n = 289). Multivariate analysis showed Scr_{(≥ 4)} (aOR 2.99, CI 1.20-7.47; p = 0.019), bipolar disorder (aOR 4.82, CI 1.25-18.83; p = 0.022), and urgent hospital complications (aOR 6.81, CI 2.02-22.91; p = 0.002), were significant independent predictors of 30-day readmissions. Early ED-visits were significantly predicted by public insurance (aOR 3.30, CI 1.22-8.91; p = 0.019), but the effect of the Scr_(≥4) profile (aOR 2.42, CI 0.97-6.09; p = 0.06), while influential, did not reach significance.

Conclusion: Differences in personality traits may be associated increased 30-day readmissions following primary bariatric surgery. Our study represents a novel application of the MMPI-2.