Methods
The meta-analysis was carried out using the MOOSE guidelines. The
studies selected were evaluated on two parameters: a)They must focus on
TNF- \(\propto\) 308 A/G polymorphism and b) They must focus on sepsis
and sepsis mortality.
The keywords used were: TNF- \(\propto\) 308 A/G, Tumour necrosis
factor, sepsis, septic shock, and sepsis mortality. The search was
carried out in MEDLINE, Scopus, and Web of Science databases. All
articles up to 2019 were considered. A total of 782 articles were
retrieved, out of which only 45 full-text articles were found to be
eligible. Out of those, 24 were used for meta-analysis after checking
the quality of articles. (Figure 1)
Figure 1 shows the selection of studies.
The studies were excluded for one of the following reasons: Duplicate
Articles studies considered multiple organ dysfunction and/or sepsis not
related to bacterial function. Three reviewers evaluated the titles,
abstracts, and text of the articles searched. The final inclusion of
articles was considered after the full agreement of the reviewers. It
was also statistically analyzed using kappa statistics; the value of
0.87 indicated a high level of agreement between the reviewers, and
hence the included studies were finalized. (Table 1)
The included studies compared G/G with G/A, G/A with A/A, and hence the
meta-analysis compared the studies taking G/G with G/A or A/A allele
combinations. G/A or A/A allele combination is referred to as TNF-2 and
G/G as TNF1. The meta-analysis also considered the ethnicity of the
study population, and it is believed to have a confounding role in the
role of TNF towards sepsis and sepsis mortality.
The meta-analysis was carried out using MedCalc Software. The comparison
of TNF factor alpha 1 and 2 among patients was calculated in the two
groups. The odds ratio of these studies was used to construct the forest
plot. The random-effects model was used with statistical significance at
a p-value less than 0.05 to assess TNF factor alpha’s association with
sepsis response.