Preventing Childhood Obesity - Evidence Policy and Practice.pdf

Chapter 12
Selective prevention programs are designed for
groups at high risk of obesity or who are already overweight
but not yet obese. Personal high - risk factors
for obesity include individual level factors, such as a
family history of obesity or non - insulin - dependent
diabetes mellitus and low resting metabolic rate: personal
eating habits and physical activity (e.g., a high -
fat diet, a sedentary lifestyle), developmental periods
associated with weight gain (e.g., pre - puberty), and
critical life events (e.g., illness). A recent systematic
review showed that such high - risk prevention strategies
have been poorly tested and have no currently
confirmed beneficial effects. 13
In the past, indicated prevention has sometimes
been referred to as secondary prevention or early
interventions. These can be designed for individuals
(in contrast to entire groups) who show biological
markers for obesity, or who are already overweight
but do not meet the diagnostic criteria for obesity.
Risk factors for such individuals include a family
history of obesity as well as biological markers and the
development of early symptoms. Although research is
still in the preliminary stages of identifying reliable
biological markers for obesity, interventions that
target individuals who are already overweight (or
whose health risks are increased owing to their weight
and/or a sedentary lifestyle) have proved to be effective
in a number of settings, including primary care.
Many approaches to prevent obesity have been proposed,
although as discussions in other chapters show,
few studies have shown long - term, sustained reductions
in weight. The emphasis on working with high -
risk individuals with interventions that are matched
or targeted to specific risk factors (as in selective and
indicated prevention strategies) appears to have considerable
value, and is a particular focus of interventions
in primary care.
In this chapter, we consider that the primary aim of
obesity prevention in primary care is to reduce the
number of new cases. An important secondary aim is
to delay the onset of obesity in those who are overweight.
Consistent with the IOM definition of prevention
(i.e., interventions that occur before onset), we
do not include a discussion of weight maintenance to
prevent the exacerbation of obesity or its complications
in those in whom the condition is established.
Neither do we cover the treatment of obesity, although
it is worth mentioning that there are research trials
and national guidelines for use of drugs and surgery
in obese adolescents. At least four national guidelines
have already issued recommendations with regard to
bariatric surgery in adolescents: National Health and
Medical Research Council ( NHMRC ) Australian
guidelines for the management of overweight and
obese children and adolescents, 14 the Singapore
Ministry of Health clinical guidelines, 15 and guidelines
from the Institute for Clinical Systems Improvement
( ICSI ), 16 and the UK Institute for Health and Clinical
Excellence (NICE). 17
This chapter is based on a literature review of published
and unpublished studies in English, conducted
in June 2008, of obesity prevention and treatment
interventions based in primary care settings worldwide.
The review considered the impact of interventions
in children of all main age - groups: preschool
(0 – 4), early school years (5 – 11) and adolescents
(12 – 18). We included clinical and non - clinical services
provided by health professionals, or associated
primary care staff, who may or may not have received
special training to manage obese children. In some
clinical programs, an individual professional provider
may work alone; in others, a multi - disciplinary group
of professional providers works together and systematically
coordinates their efforts.
Evidence and g uidelines for
o besity p revention i nterventions
in p rimary c are
Evidence from a ll c linical s ettings
There is limited evidence on the essential components
of effective health sector interventions for childhood
obesity. However, throughout the literature it appears
that a multi - disciplinary approach is most commonly
advocated. Programs normally include one or several
of the following components:
• nutritional and physical activity advice
• behavioral treatment components
• decreasing sedentary activities and increasing
lifestyle - related physical activity
• social and/or psychological support involving
families.
There have been several extensive literature reviews
of the evidence for management and treatment
of childhood obesity including a 2003 Cochrane
review, 18 which was updated in 2006 for the UK
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