Assessment of obesity beyond body mass index to determine benefit of treatment

Abstract

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Weight or weight loss per se may not indicate health status or health benefit. • There is no gold standard for assessing which patients would benefit most from weight-loss interventions. • The King's Criteria is one of several recently proposed obesity classification systems. WHAT THIS STUDY ADDS: • The King's Criteria can capture health problems related to obesity and health benefits after weight loss. • The King's Criteria is a reproducible scoring system. • Using the King's Criteria may help shift the focus of patients and clinicians from weight loss to health gain. SUMMARY: Body mass index (BMI) alone does not reflect health status in individuals. The King's Obesity Staging Criteria is a clinical tool for the assessment of patients with complex obesity. We assessed the performance of a modified version of the King's Criteria by scoring 144 obese patients before and 1 year after bariatric surgery. We also evaluated inter-observer variability by having 11 clinicians score the same 12 patients. The King's Obesity Staging Criteria comprise nine health domains: Airways, Body mass index, Cardiovascular disease, Diabetes, Economic complications, Functional limitations, Gonadal axis, Health status (perceived), and body Image. For each domain, a person's health is assigned a score of 0 ('normal health'), 1 ('at risk'), 2 ('established disease') or 3 ('advanced disease'). The patient's mean BMI decreased from 48 ± 7 to 37 ± 7 kg m(-2) post surgery. Before surgery, 84% of patients were either in stage 2 ('established disease') or stage 3 ('advanced disease') for one or more domains other than BMI. The modified King's Criteria showed significant health improvements after surgery, with a higher proportion of patients scored in stage 0 ('normal health') within each health domain (P < 0.001 for all). Observers assigned the same score in >75% of cases for all domains except Health status perceived (71%) and body Image (65%). In conclusion the King's Criteria captured morbidity in obese patients and health gains after weight loss. Different clinicians mostly assigned similar scores. The King's Criteria is a clinical tool that may help shift the focus of patients and clinicians towards improving health and not only losing weight. REGISTRATION NUMBER: NCT01112228 (http://www.clinicaltrials.gov).