Vol 44 # 4 December 2012 - Kma.org.kw

December 2012
KUWAIT MEDICAL JOURNAL 274
Editorial
Bariatric Surgery and Hypoglycemia
Bijan Ahrari, Samuel Dagogo-Jack
Department of Medicine, Division of Endocrinology, Diabetes and Metabolism, University of Tennessee Health Science
Center, Memphis, Tennessee, USA
Kuwait Medical Journal 2012; 44 (4): 274 - 276
Obesity is a major public health problem in the
developed and developing regions of the world.
Using a body mass index (weight in kg divided by
height in meter squared) of 30 kg/m 2 or greater as the
cut-off, recent estimates indicate that 36% of adults
in the United States are obese [1] . The prevalence of
severe or morbid obesity defined as BMI greater
than 40 kg/m 2 is rising twice as fast as that of obesity
and is currently close to 6% of US adult population.
Obesity is associated with increased risk of morbidity
and mortality from cardiovascular disease, diabetes,
respiratory diseases, musculoskeletal disorders and
neoplastic diseases, among others [2] . Management of
obesity continues to be challenging, and traditional
options based on dietary and lifestyle modifications
seldom result in sustained weight loss. Compared
with the proliferation of agents for diabetes therapy,
the pace of drug development for obesity has been
markedly slower. Moreover, the available agents are
of limited efficacy [3] , especially with regard to making
an impact on morbid obesity.
Superficial interventions such as liposuction
and removal of subcutaneous abdominal adipose
tissue do not alter cardio-metabolic risks [4] . By
contrast, gastric bypass surgery offers long-term
weight loss associated with significant reduction
of comorbidities associated with morbid obesity [5] .
Complete resolution of diabetes occurs in 80% of
patients while an additional number of patients see
significant improvement in diabetes [6,7] . This happens
through both weight-dependent as well as weightindependent
mechanisms including alteration in
bile flow, reduction of gastric size, anatomical gut
rearrangement, vagal manipulation, and alterations
in enteric hormones [6] . In addition, hyperlipidemia,
hypertension and obstructive sleep apnea improve in
70%, 62% and 84% of patients respectively [8] . A large
cohort study showed a 40% reduction in mortality
from all causes associated with bariatric surgery [9] .
Unfortunately, the cosmetic and cardio-metabolic
benefits of bariatric surgery are achieved at a price of
significant post-operative morbidity and sometimes
mortality. However, the outcomes of bariatric surgery
are generally improving over time with the use of more
advanced surgical procedures, more careful selection
of surgical candidates, and the use of specialized
surgery centers. The overall 30-day mortality
for bariatric surgical procedures is less than one
percent [8] . Some of the more common complications of
bariatric surgery include ventral and internal hernias,
metabolic and nutritional derangements, marginal
ulcers, short bowel syndrome, dumping syndrome
and cholelithiasis [10] .
An uncommon but potentially serious adverse effect
of bariatric surgery is recurrent severe hypoglycemia.
As is well-known, hypoglycemia is rare among nondiabetic
persons [11] . Although mild asymptomatic
hypoglycemia can be as seen in up to 50% of postbypass
patients, severe hypoglycemia accompanied by
neuroglycopenic symptoms occurs in less than 1% of
bariatric surgery patients [6,12] . The presentation of mild
episodes of hypoglycemia is similar to that of the late
phase of dumping syndrome and usually responds to
dietary modifications [5] . Although much less frequent,
episodes of severe hypoglycemia can have dramatic
clinical presentations, including confusion, seizure
and coma. Impaired cognitive function, altered
neuromuscular reflexes, and diminished capacity for
judgment resulting from neuroglycopenia can lead
to automobile accidents and machinery injuries. In
a nationwide Swedish case-control study (one case
for every 10 matched population control subjects)
of persons who had undergone gastric bypass (n =
5,040), vertical banded gastroplasty (n = 4,366), or
Address correspondence to:
Samuel Dagogo-Jack, MD, University of Tennessee Health Science Center, 920 Madison Avenue, Suite 300A, Memphis, TN 38163, USA. Tel:
901-448-5318, Fax: 901-448-5332, E-mail: sdj@uthsc.edu