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Meta-Analysis
. 2021 Aug 12:12:728396.
doi: 10.3389/fendo.2021.728396. eCollection 2021.

The Impact of Helminth Infection on the Incidence of Metabolic Syndrome: A Systematic Review and Meta-Analysis

Claire Rennie  1 , Ritin Fernandez  2   3   4 , Sheila Donnelly  1 , Kristine Cy McGrath  1
Affiliations
Meta-Analysis

The Impact of Helminth Infection on the Incidence of Metabolic Syndrome: A Systematic Review and Meta-Analysis

Claire Rennie et al. Front Endocrinol (Lausanne). .

Abstract

Background: There are a growing number of publications that report an absence of inflammatory based disease among populations that are endemic to parasitic worms (helminths) demonstrating the ability of these parasites to potentially regulate human immune responses. The aim of this systematic review and meta-analysis was to determine the impact of helminth infection on metabolic outcomes in human populations.

Methods: Using PRISMA guidelines, six databases were searched for studies published up to August 2020. Random effects meta-analysis was performed to estimate pooled proportions with 95% confidence intervals using the Review Manager Software version 5.4.1.

Results: Fourteen studies were included in the review. Fasting blood glucose was significantly lower in persons with infection (MD -0.22, 95% CI -0.40- -0.04, P=0.02), HbA1c levels were lower, although not significantly, and prevalence of the metabolic syndrome (P=0.001) and type 2 diabetes was lower (OR 1.03, 95% CI 0.34-3.09, P<0.0001). Infection was negatively associated with type 2 diabetes when comparing person with diabetes to the group without diabetes (OR 0.44, 95% CI 0.29-0.67, P=0.0001).

Conclusions: While infection with helminths was generally associated with improved metabolic function, there were notable differences in efficacy between parasite species. Based on the data assessed, live infection with S. mansoni resulted in the most significant positive changes to metabolic outcomes.

Systematic review registration: Website: PROSPERO Identified: CRD42021227619.

Keywords: helminth infection; helminth therapy; metabolic syndrome; parasitic worms; type 2 diabetes mellitus.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Flow diagram of study selection.
Figure 2
Figure 2
Effect of infection on fasting blood glucose. Forest plot summarising that of the 5 studies included herein, all report lower mean FBG levels in an infected population.
Figure 3
Figure 3
Effect of infection on HbA1c. (A) Forest plot of studies that measured HbA1c. Together, lower HbA1c is favored by infection. (B) Subgroup analysis excluding populations with diabetes only, infection favors lower HbA1c.
Figure 4
Figure 4
Effect of infection on the prevalence of the metabolic syndrome. Forest plot of studies which both individually and taken as a whole, demonstrate the protective effect of infection on prevalence of the MetS.
Figure 5
Figure 5
Prevalence of type 2 diabetes in infected or non-infected individuals. (A) Forest plot of studies illustrating that prevalence of T2D is not affected by infection when all studies are pooled. Subgroup analysis of only Schistosoma infection shows infection is associated with lower prevalence of T2D. (B) Forest plot of an infected population with diabetes vs. an infected population without diabetes shows people are less likely to develop diabetes if infected.
See this image and copyright information in PMC

References

    1. Internal Clinical Guidelines Team . Type 2 Diabetes in Adults: Management. London, UK: National Institute for Health and Care Excellence; (2015). - PubMed
    1. International Diabetes Federation . About Diabetes (2015). Available at: http://www.idf.org/about-diabetes.
    1. Sattar N, McConnachie A, Shaper AG, Blauw GJ, Buckley BM, de Craen AJ, et al. . Can Metabolic Syndrome Usefully Predict Cardiovascular Disease and Diabetes? Outcome Data From Two Prospective Studies. Lancet (2008) 371(9628):1927–35. 10.1016/S0140-6736(08)60602-9 - DOI - PubMed
    1. Verma S, Hussain ME. Obesity and Diabetes: An Update. Diabetes Metab Syndr: Clin Res Rev (2017) 11(1):73–9. 10.1016/j.dsx.2016.06.017 - DOI - PubMed
    1. Saeedi P, Petersohn I, Salpea P, Malanda B, Karuranga S, Unwin N, et al. . Global and Regional Diabetes Prevalence Estimates for 2019 and Projections for 2030 and 2045: Results From the International Diabetes Federation Diabetes Atlas, 9th Edition. Diabetes Res Clin Pract (2019) 157:107843–53. 10.1016/j.diabres.2019.107843 - DOI - PubMed

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