2004 ASBS Consensus Conference
Patient selection for treatment of obesity
John G. Kral, M.D., Ph.D., F.A.C.S.*
Department of Surgery, State University of New York Downstate Medical Center, Brooklyn, New York
Keywords: Appetite regulation; Disease severity; Motivation for treatment; Predictors of outcome; Surgical outcome;
Weight loss
Because of the multifactorial etiology of obesity, ranging
from genetic to epigenetic to early-life environmental
causes to conscious and unconscious lifestyle choices, post-
traumatic conditions, and codependencies, patient selection
is crucially important for “successful” treatment. Because
maintenance of weight loss is the critical advantage of
surgical treatment over other modalities, it is necessary to
focus on predictors of long-term response to surgery. This
review proposes standards for reporting outcomes and sum-
marizes methods for selecting candidates for surgical treat-
ment of obesity. Motivational factors influencing outcome
are paramount, emphasizing the importance of analyzing
behavior and the need for individualizing (surgical) treat-
ment options.
The trend toward younger age and lower weight criteria
increases the need for improved patient selection for obesity
surgery. Surgical treatment of severely obese patients is
more cost-effective and has a better risk– benefit ratio than
any nonoperative modality, but there is considerable need
for improvement. Laparoscopic approaches and other tech-
nical advances have increased safety, and our understanding
of the disease of obesity has improved dramatically, via
molecular biology and sophisticated integrative physiology.
Nevertheless, this progress has not translated into the criti-
cal clinical area of patient selection. This overview summa-
rizes old and new predictors of outcome of surgical treat-
ment of obesity and suggests areas of further investigation.
The traditional medical practice paradigm formalized in
the outline of the medical record as “history and physical”
ends with an “impression,” or problem statement conceptu-
ally related to patient selection. The patient is selected for a
workup and (ultimately) a treatment plan based on needs
assessment, prognosis, and risk-benefit analysis. Although
modern medicine has become increasingly reliant on pro-
cedures and technology, evaluation of obesity, more than
most other diseases, benefits from a thorough history and
physical, with emphasis on the needs assessment elicited
from skilled history-taking.
Goals, definitions, and stipulations
Patient selection has 3 goals: to (1) maximize perioper-
ative safety, (2) minimize long-term surgical complications/
side effects, and (3) optimize long-term benefits of obesity
treatment. Established clinical physiological predictors re-
lated to a patient’s ability to safely undergo any operation
(goal 1), exemplified by the American Anesthesiology As-
sociation (ASA) score and similar classifications [1,2], are
the same in obese and nonobese patients and are not re-
viewed here, keeping in mind that obesity in and of itself is
a risk factor [3,4]. Together, goals 2 and 3 compose the
risk– benefit ratio, central to all surgical thinking, and are
integral components of patient selection.
“Long-term” in the context of evaluating the benefits of
surgical treatment of obesity is defined as follow-up care for
5 years or more, which is substantially longer than the
follow-up of other treatments. Comorbidity reduction and
weight loss data accumulated during ongoing, dynamic
weight loss, in the absence of a steady state, are meaning-
less. Suggested criteria for weight stability are given later in
this review. In 1994, Knol identified 5 categories of prob-
lems associated with poor long-term outcomes: (1) inade-
quate patient knowledge, (2) psychological maladaptation,
(3) anatomic complications, (4) gastrointestinal pathophys-
iology, and (5) weight-related symptomatology [5]. There is
*Reprint requests: John G. Kral, M.D., Ph.D., Department of Surgery,
Box 40, SUNY Downstate Medical Center, 450 Clarkson Ave., Brooklyn,
NY 11203-2098.
E-mail: jkral@downstate.edu
Surgery for Obesity and Related Diseases 1 (2005) 126 –132
1550-7289/05/$ – see front matter © 2005 American Society for Bariatric Surgery. All rights reserved.
doi:10.1016/j.soard.2005.02.005