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Published on: July 21, 2023
Microvascular complications in prediabetes: a systematic review & meta-analysis
Sama Thiab1, Taim Akhal1, Meriem Akeblersane1
1School of Medicine, Royal College of Surgeons in Ireland Bahrain, Busaiteen 15503, Bahrain.
Insights
The American Diabetes Association (ADA) prediabetes criteria (HbA1c ≥ 5.7%) identify more retinopathy than International Experts Committee (IEC) criteria. ADA criteria are preferable for early retinopathy detection in prediabetes.
Area of Science:
- Endocrinology
- Ophthalmology
- Nephrology
Background:
- Rising prediabetes prevalence increases microvascular complication risk.
- Discrepancies exist between ADA (HbA1c 5.7-6.4%) and IEC (HbA1c 6.0-6.4%) prediabetes definitions.
- Identifying optimal prediabetes screening criteria for microvascular complications is crucial.
Purpose of the Study:
- To determine if a specific prediabetes hemoglobin A1c (HbA1c) or fasting blood glucose (FBG) threshold increases microvascular complications.
- To compare the efficacy of ADA versus IEC criteria in identifying retinopathy risk.
Main Methods:
- Systematic review of prediabetes studies (1990-May 2023) in major databases.
- Included studies reporting retinopathy, nephropathy, and/or neuropathy.
- Analyzed 35 studies out of 21,215 identified.
Main Results:
- ADA criteria identified significantly higher prevalence and incidence of retinopathy compared to IEC criteria.
- Receiver Operator Curve analysis showed better performance for IEC criteria in retinopathy detection (AUC 0.88) versus ADA criteria (AUC 0.73).
- Limited data available for nephropathy and neuropathy prevalence in prediabetes.
Conclusions:
- ADA prediabetes criteria (HbA1c 5.7-6.4%) are more sensitive for detecting retinopathy than IEC criteria (HbA1c 6.0-6.4%).
- Clinical retinal screening may be beneficial for individuals with HbA1c ≥ 5.7%.
- Further research is needed on nephropathy and neuropathy prevalence in prediabetes.
Aims:
Prediabetes prevalence is increasing with a risk of developing microvascular complications. The American Diabetes Association (ADA) definition is a hemoglobin A1c(HbA1c) of 5.7 %-6.4 % (39-46 mmol/mol) versus the International Experts Committee (IEC) range of 6.0-6.4 % (42-46 mmol/mol). We aimed to determine whether a prediabetic HbA1c or fasting blood glucose (FBG) cut-off exists, above which individuals exhibit increased microvascular complications.
Methods:
All prediabetes studies in Embase, MEDLINE, Scopus, Cochrane, CINAHL databases from 1990-May 2023 reporting retinopathy, nephropathy, and/or neuropathy included.
Results:
21,215 studies identified, 35 analyzed.Prevalence and incidence of retinopathy was significantly higher by ADA versus IEC criteria (Weighted Mean Difference 2.37 [2.31,2.43] and 1.32 [1.25,1.40], respectively). Receiver Operator Curves for IEC criteria: sensitivity 65.3% specificity 88.0% for retinopathy, AUC 0.88; for ADA criteria at 5.9%: sensitivity 77.5%, specificity 78.4%, AUC 0.73. No studies reported nephropathy/neuropathy by IEC criteria; nephropathy prevalence 1.0%-15.0% for HbA1c and FBG criteria.
Conclusions:
Prediabetes ADA criteria (HbA1c 5.7-6.4 %) identified significantly more retinopathy than IEC criteria (HbA1c 6.0-6.4 %), suggesting that ADA criteria are preferable for early retinopathy detection and clinical retinal screening may be considered at HbA1c ≥ 5.7 %. Insufficient studies on the prevalence of nephropathy and neuropathy in prediabetes were available.
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