Methods
To identify studies that are relevant to the current
study, a systematic review was conducted with the
Medline, Embase and PsycInfo databases, using the
keywords “metabolic syndrome”, “insulin resistance”
and “metabolic X syndrome”, and cross-referencing
them with “bipolar disorder” or “mania”. The search was
conducted during May of 2012 and was limited to human
studies published in English. Duplicated articles were
excluded. The remaining paper titles and abstracts
were used to determine whether the reference might be
pertinent to the review. The following types of publications
were candidates for review: (i) clinical trials, (ii) studies
involving patients diagnosed with bipolar disorder, or (iii)
data about metabolic syndrome.
To assess the methodological weight of the studies,
a 5-point quality scale was used that included the
following items: a sample with at least 100 BD patients,
a standardized BD diagnostic measure, use of the NCEP
National Cholesterol Education Program (NCEP) or the
International Diabetes Federation (IDF) criteria for MS,
and a central aim of evaluating MS in BD patients or
of comparing BD patients to controls or data from the
general population. This quality score was based on a
similar scoring method that used for two other published
review articles relevant to the current study.7,