Relationship between insulin-sensitive obesity and retinal microvascular abnormalities

Area of Science:

• Ophthalmology
• Endocrinology
• Public Health

Background:

• Obesity and insulin resistance (IR) are established risk factors for microvascular disease (MVD).
• The specific risk posed by obesity in insulin-sensitive individuals to MVD remains unclear.
• This study investigates the association between insulin-sensitive obesity and retinal microvascular abnormalities.

Purpose of the Study:

• To determine if insulin-sensitive obesity is linked to retinal microvascular abnormalities.
• To assess the risk of MVD in obese individuals, considering insulin sensitivity and abdominal obesity.
• To explore the role of obesity as a potential precursor to MVD, similar to diabetes mellitus.

Main Methods:

• A cross-sectional study involving 8,313 participants (aged 21+) in China.
• Participants were classified based on insulin sensitivity/resistance and general/abdominal obesity.
• Retinal microvascular abnormalities, indicative of MVD, were diagnosed via direct ophthalmoscopy.

Main Results:

• Obese older adults (65-79 years) exhibited a significantly higher risk of MVD, regardless of insulin sensitivity.
• Abdominal obesity, both insulin-sensitive and insulin-resistant, was associated with an increased risk of MVD in middle-aged women.
• Specific odds ratios (OR) and confidence intervals (CI) were reported for these associations.

Conclusions:

• Obesity is strongly associated with an elevated risk of MVD, particularly in older individuals and abdominally obese middle-aged women, irrespective of insulin resistance.
• Direct ophthalmoscopy presents a potential non-invasive screening method for obesity-related MVD.
• Insulin-sensitive obesity may represent an early stage preceding insulin-resistant obesity and its complications.