Type I diabetes has a strong correlation with gluten intolerance. Because of this association, gluten-intolerant individuals may have increased risk for microvascular complications, including retinopathy, neuropathy, and nephropathy.
Prior studies have demonstrated the deleterious effects of gluten intolerance on neuropathy (Lancet 1998;352(9140):1582-1585; J Neurol Neurosurg Psychiatry 2003;74:490-494).
Interestingly, type I diabetes patients with celiac disease (CD) often have reduced rates of albumin excretion when compared to non-CD diabetics (Pediatr Diabetes 2013;14:455-458). Researchers have questioned whether a gluten-free diet is protective in this manner.
A prior study did not find increased risk of CD in type 1 diabetic patients who also exhibited nephropathy (Diabetologia 2005;48:1416-1417), but diabetic CD patients compliant with gluten-free diets have been shown to have reduced albumin to creatinine ratios and reduced advanced glycation end-products (AGEs) compared with non-CD diabetics (Diabetologia 2009;52:798-800).
Another study found improvements in newly diagnosed CD patients after one year of gluten-free diet adherence (Diabetes Care 2011;34:2158-2163).
These improvements included an increase in high-density lipoprotein (HDL) cholesterol and a decrease in hemoglobin A1c, cholesterol to HDL ratio, triglycerides, and urinary albumin to creatinine ratio. Advanced nephropathy appeared to improve, but due to a small sample size, statistical significance was not achieved. Retinopathy improved after one year of gluten-free diet intervention.
Similarly, another study failed to find an association between risk rates of type I diabetics with or without CD and nephropathy, but CD patients following a gluten-free diet had reduced rates of retinopathy (Acta Diabetol 2013;50:319-324). A recent study found that CD patients who did not comply with a gluten-free diet had significantly higher albumin excretion rates compared with non-compliant individual (Diabet Med 2013; published online ahead of print).