AIP flags kidney and nerve damage risk despite target LDL in type 2 diabetes

A Shenzhen study of 16,469 adults suggests a triglyceride-to-HDL measure could reveal residual kidney and nerve complication risk in people with type 2 diabetes whose LDL cholesterol is already at target.

A large real-world study from Shenzhen suggests that a common measure of blood fat balance may help identify people with type 2 diabetes who remain at risk of serious small-vessel complications even after reaching recommended LDL cholesterol targets. Published in the Journal of Global Health, the analysis tracked 16,469 adults with type 2 diabetes and found that a higher atherogenic index of plasma, or AIP, was linked to a greater risk of diabetic kidney disease and diabetic peripheral neuropathy, but not clearly to diabetic retinopathy. The findings matter because the International Diabetes Federation says about 589 million adults worldwide are living with diabetes, underlining the scale of the condition and the need for better ways to spot residual risk.

The study focused on patients whose LDL cholesterol was already below 2.6 mmol/L, the level commonly recommended in diabetes care. Researchers used community health records collected between 2018 and 2024 and grouped participants by AIP, a calculation based on triglycerides and high-density lipoprotein cholesterol. Over a median follow-up of 4.6 years, 1,056 participants developed microvascular complications. Those in the highest AIP group had a significantly higher overall risk than those in the lowest group, even after adjustment for age, sex, education, lifestyle factors, diabetes duration, hypertension and medication use.

The association was strongest for kidney and nerve complications. In the fully adjusted model, people in the highest AIP group had a 62% higher risk of diabetic nephropathy and a 39% higher risk of diabetic peripheral neuropathy than those in the lowest group. By contrast, the link with diabetic retinopathy was not statistically significant. When AIP was analysed as a continuous measure, the same pattern held: risk rose for kidney disease, neuropathy and the combined microvascular outcome, while the eye outcome remained inconclusive.

The findings add to earlier evidence suggesting that AIP may capture risk that LDL cholesterol alone misses. Previous studies have linked higher AIP with cardiovascular events in type 2 diabetes and with some microvascular outcomes, including kidney disease and retinopathy, but the evidence has been mixed. The Shenzhen researchers argue that their study is notable because it examined a population already at LDL target, a group in which standard lipid control may leave meaningful residual risk. That is particularly relevant in diabetes, where triglyceride-rich lipoproteins, low HDL cholesterol and insulin resistance can continue to drive vascular injury even when LDL cholesterol looks satisfactory.

The pattern was not uniform across organs, however. The authors point out that the kidney and peripheral nerves may be especially vulnerable to lipid-related damage, while the retina appears to be influenced by additional or different pathways. They also found that the association with neuropathy was stronger in older participants, suggesting age may shape how AIP relates to complications. Still, the study was observational and relied on inpatient records, so some cases diagnosed in outpatient care may have been missed. The data also came from one Chinese city, which limits how far the results can be applied elsewhere.

Even with those caveats, the study suggests AIP could serve as a practical complement to LDL cholesterol in routine diabetes management. For clinicians, the message is not that LDL control should be relaxed, but that it may not tell the full story. In people with type 2 diabetes, especially those who already meet LDL targets, a higher AIP could flag a need for closer surveillance of kidney and nerve health and for broader efforts to reduce cardiometabolic risk.