Plasma Homocysteine is Associated with Retinopathy in Type 1 Diabetic Patients in the Absence of Nephropathy.
BACKGROUND
Previous cross-sectional studies suggested that plasma total homocysteine (tHcy) is associated with retinopathy in patients with type 1 diabetes (T1DM) only in cases of impaired renal function. The objective of this study was to examine whether there is an independent relationship between tHcy and retinopathy in normoalbuminuric T1DM patients with normal estimated glomerular filtration rate (eGFR).


METHODS
The study included 163 normoalbuminuric patients with T1DM and normal renal function (eGFR >60 ≤ 125 ml min(-1) 1.73 m(-2)). Urinary albumin excretion rate (UAE) was measured from at least two 24 h urine samples. Photodocumented retinopathy status was made according to the EURODIAB protocol. tHcy level was measured with the chemiluminescent immunoassay.


RESULTS
Retinopathy was present in 48% of normoalbuminuric patients. Patients with retinopathy were older (49 vs 42 years, p = 0.001), had higher systolic blood pressure (130 vs 120 mmHg, p = 0.001), triglycerides (0.89 vs 0.77 mmol/L, p = 0.01), tHcy (9.8 vs 9.1 µmol/L, p = 0.04), and lower eGFR (100 vs 106 ml min(-1) 1.73 m(-2), p = 0.03). In multivariate logistic regression analysis, after adjustment for variables that reached statistical significance in the univariate analysis, only tHcy was significantly associated with a risk of retinopathy in our subjects (p = 0.02), with odds ratios of 1.02 to 1.43.


CONCLUSIONS
These data suggest that tHcy is independently associated with retinopathy in normoalbuminuric T1DM with normal eGFR. The mechanisms relating tHcy and retinopathy in T1DM are not clear. Prospectives studies are needed to confirm whether higher tHcy in normoalbuminuric T1DM patients has predictive value for development of retinopathy.
a Vuk Vrhovac Clinic for Diabetes, Endocrinology and Metabolic Diseases, University Hospital Merkur, University of Zagreb , Zagreb , Croatia.
Tomislav
T
Bulum
a Vuk Vrhovac Clinic for Diabetes, Endocrinology and Metabolic Diseases, University Hospital Merkur, University of Zagreb , Zagreb , Croatia.
Kristina
K
Blaslov
a Vuk Vrhovac Clinic for Diabetes, Endocrinology and Metabolic Diseases, University Hospital Merkur, University of Zagreb , Zagreb , Croatia.
Lea
L
Duvnjak
D000328:Adult; D000368:Aged; D000419:Albuminuria / Q000652:urine; D001786:Blood Glucose / Q000378:metabolism; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy; D003928:Diabetic Nephropathies / Q000175:diagnosis; D003930:Diabetic Retinopathy / Q000097:blood* / Q000175:diagnosis; D005260:Female; D005919:Glomerular Filtration Rate; D006442:Glycated Hemoglobin / Q000378:metabolism; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D055815:Young Adult
D001786:Blood Glucose; D003404:Creatinine; D006442:Glycated Hemoglobin; D006710:Homocysteine; D007004:Hypoglycemic Agents; D007328:Insulin; C517652:hemoglobin A1c protein, human
Homocysteine; microvascular complications; retinopathy; type 1 diabetes