# Two types of Wechsler Adult Intelligence Scale (WAIS) index discrepancies are associated with insufficient weight reduction after sleeve gastrectomy in adult patients with obesity: a retrospective study

## TL;DR

This study found that specific patterns in IQ test scores are linked to less weight loss after sleeve gastrectomy in obese patients.

## Contribution

It identifies two types of WAIS index discrepancies associated with insufficient weight reduction after bariatric surgery.

## Key findings

- Patients with WAIS discrepancies between PRI/WMI and PSI had lower weight loss after surgery.
- Those with PRI > PSI discrepancies had significantly worse weight loss outcomes than PRI < PSI discrepancies.

## Abstract

Obesity is a major global health concern. Laparoscopic sleeve gastrectomy (LSG) has demonstrated excellent therapeutic effects. Further, intelligence quotient (IQ) is an important factor in obesity; however, full-scale IQ is not associated with weight reduction after LSG. IQ and IQ index score discrepancies are also important when considering IQ tests. However, the relationship between IQ or IQ index score discrepancies and weight reduction after bariatric surgery remains unexplored. This study aimed to elucidate the relationship between IQ index score discrepancies and weight reduction following LSG.

In total, 204 patients with obesity who underwent LSG and were followed up for 12 months were retrospectively reviewed. The relationship between IQ, the Wechsler Adult Intelligence Scale (WAIS) index score discrepancy, and various clinical parameters, particularly weight reduction, after LSG was analyzed. A logistic regression analysis was performed.

The percentage of excess weight loss (%EWL) was 64.2 (49.6–84.5%) 12 months post-LSG. IQ scores were not associated with preoperative body mass index. However, patients with WAIS index score discrepancies between the perceptual reasoning index (PRI), processing speed index (PSI), and working memory index (WMI) had low %EWL. Logistic regression analysis revealed that the existence of WAIS index score discrepancies between the PRI/WMI and PSI was associated with low %EWL post-LSG. Further, patients with WAIS index score discrepancies in the PRI > PSI group had significantly lower %EWL than those in the PRI < PSI group.

These results show that the existence of WAIS index score discrepancies between the PRI/WMI and PSI is associated with insufficient weight reduction after LSG in patients with obesity.

The online version contains supplementary material available at 10.1186/s40001-025-03758-y.