Comparison of Mortality Outcomes in Type 2 Diabetes amongst different Ethnic Groups: Systematic review and Meta-analysis of Longitudinal Studies

Conference:

SAPC ASM 2024 - Bristol

Talk Code:

5C.3

Presenter:

Umar A R Chaudhry

Twitter:

@Dr_UmarChaudhry

Co-authors:

Umar A R Chaudhry[1], Rebecca Fortescue[1], Liza Bowen[1], Stephen Woolford[1], Felicity Knights[2], Julia A Critchley[1], Derek G Cook[1], Tess Harris[1]

Author institutions:

[1] - Population Health Research Institute, St George’s, University of London, London; [2] - Institute for Infection and Immunity, St George's University of London, London

Problem

Type 2 diabetes is a leading cause of morbidity and mortality. People of certain ethnic groups are known to be disproportionately affected by type 2 diabetes. Its prevalence is higher and age of onset up to ten years earlier in people of in South Asian and Black ethnicities compared to people of White ethnicities, which can lead to several complications. Comparisons of mortality outcomes by different ethnic groups have however not been extensively studied to include the more recent larger studies, and robust estimates are important to identify key risk factors for any mortality differences. The aim of this systematic review and meta-analysis is to compare mortality outcomes in people with type 2 diabetes amongst different ethnic groups.

Approach

This systematic review follows PRISMA guidelines, and a PROSPERO protocol has been registered(CRD42022372542). Eight databases and grey literature were searched in March 2023 for longitudinal follow-up studies (prospective and retrospective cohorts) using suitable MeSH headings and keywords. Studies among adults with type 2 diabetes managed in community-based settings, published after 01/01/2000 and containing ≥100 participants in each reported ethnic group were included. Two independent reviewers undertook title/ abstract and full-text screening, data extraction, quality assessment using the using Newcastle-Ottawa Scale (NOS) and data synthesis with group consensus to resolve any conflicts. The primary outcome was all-cause mortality rates amongst different ethnic groups in type 2 diabetes, with comparisons reported as a hazard ratio (HR) with 95% confidence intervals (95%CI).

Findings

30,825 records were identified through initial database searching, 14,640 studies were eligible fortitle/abstract screening, of which 258 studies underwent full-text screening. 13 studies met the selection criteria to be included in the systematic review, of which 9 studies had sufficient data for quantitative synthesis in a meta-analysis. The 13 studies included were predominantly conducted in UK, north America and Australasia countries, incorporated a total of 812,049 participants and 12/13 were rated as good using the NOS for quality assessment. The overall risk of mortality was lower amongst people with type 2 diabetes from South Asian [HR 0.68 (0.65-0.72); 4 studies], Black [HR 0.82 (0.77-0.87); 5 studies] and Chinese [HR 0.57 (0.46-0.70); 2 studies] ethnicity compared to people of White ethnicity.

Consequences

People with T2D of South Asian, Black and Chinese ethnicity have a lower risk of all-cause mortality compared to people of White ethnicity. This is the first systematic review providing comprehensive estimates for mortality risk by ethnicity in people with type 2 diabetes, incorporating more recent, larger cohorts. Key influences explaining higher mortality risk in certain ethnic groups therefore require further study, which will provide opportunities for more focussed interventions to reduce these differences, and lead to more equitable type 2 diabetes management.

Submitted by:

Umar Chaudhry

Funding acknowledgement:

No funding was available for this study.