Frequency of Early Microvascular Changes in Prediabetic Individuals: A Focus on Renal, Retinal, and Peripheral Nerve Involvement

TL;DR

This study finds that prediabetic individuals often show early microvascular changes in the kidneys, eyes, and nerves, linked to age, obesity, and other risk factors.

Contribution

The study quantifies the frequency of early microvascular complications in prediabetic individuals and identifies key risk factors for these changes.

Findings

Microvascular changes were most common in overweight and obese prediabetic individuals.

Hypertension and dyslipidemia were significantly associated with microvascular complications.

Early screening for albuminuria, retinopathy, and neuropathy is recommended to prevent diabetes progression.

Abstract

Background and objective: Prediabetes is increasingly recognized as a stage where microvascular injury begins, particularly involving renal, retinal, and neural pathways. Early detection of such changes may guide timely interventions. This study aimed to determine the frequency of early microvascular complications in prediabetic individuals and evaluate their association with clinical and biochemical risk factors.

Methods: This cross-sectional observational study was conducted at Lahore General Hospital, Lahore, Pakistan, from July 2023 to June 2024. A total of 268 prediabetic adults, defined by the American Diabetes Association (ADA) 2023 criteria, were enrolled using non-probability consecutive sampling. Microvascular outcomes were assessed by urine albumin-to-creatinine ratio (UACR), the Michigan Neuropathy Screening Instrument, and the Early Treatment Diabetic Retinopathy Study (ETDRS)-based fundus photography. Biochemical tests included fasting glucose, two-hour oral glucose tolerance test (OGTT), and glycated hemoglobin (HbA1c).

Results: In this study of 268 prediabetic individuals, the mean age was 46.07±7.65 years, with a higher mean age among those with microvascular changes (48.44±9.21 vs. 45.64±7.28 years; p=0.031). The mean body mass index (BMI) was 27.99±3.59 kg/m², with significantly higher values in those with microvascular changes (p<0.001). Microvascular changes were most frequent in overweight (48.8%) and obese (36.6%) participants compared to those of normal weight (14.6%; p=0.017). Hypertension (58.5% vs. 39.6%; p=0.024) and dyslipidemia (78% vs. 51.5%; p=0.002) were significantly associated, whereas smoking (p=0.126) and family history of diabetes (p=0.296) were not. Biochemical parameters were significantly higher in those with microvascular changes: fasting plasma glucose (p<0.001), two-hour OGTT (p<0.001), HbA1c (6.11% vs. 5.92%; p=0.001), and UACR (p<0.001). Microalbuminuria was detected in 10.1%, retinopathy in 4.1%, and peripheral neuropathy in 7.8%.

Conclusion: Early microvascular changes were observed in prediabetes, with significant associations with age, BMI, hypertension, dyslipidemia, and glycemic indices. Screening for albuminuria, retinopathy, and neuropathy may enable timely interventions to prevent progression to diabetes and related vascular complications.

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