Characteristics of Type 1 diabetes of over 50 years duration (the Golden Years Cohort).
BACKGROUND
Type 1 diabetes mellitus is associated with high levels of premature morbidity and mortality. Prolonged survival is possible, however, and some patients appear to be protected from the long-term complications of this condition.


METHODS
Diabetes UK awards medals to patients who have had Type 1 diabetes for 50 years or more. By examining medal-holders, we have established the clinical and biochemical features of a group of 400 subjects (54% male) with Type 1 diabetes of long duration.


RESULTS
Mean age of the subjects was 68.9 years and mean age-at-onset of diabetes 13.7 years. Features of long duration diabetes in this cohort include normal body mass (mean BMI 25.0 kg m-2), low insulin dose (mean 0.52 units kg-2) and greatly elevated HDL-cholesterol (mean 1.84 mmol/l). Mean HbA1c was 7.6% (normal range 3.8-5.0%) and no patient had a normal HbA1c at the time of venesection. As a group, they have long-lived parents and consume moderate amounts of alcohol. Medical contact has often been sporadic. A significant proportion (29%) were taking anti-hypertensive medication. Screening for micro- and macroalbuminuria was positive in 35.7%.


CONCLUSIONS
Patients with long-duration (> 50 years) Type 1 diabetes are relatively protected from clinical diabetic nephropathy and large vessel disease; our data are consistent with protection possibly being genetically determined in part via elevated HDL-cholesterol levels. An abnormal urinary albumin/creatinine ratio is common in these patients, despite their low risk of significant renal deterioration; this may have implications for microalbuminuria screening programmes.
D000368:Aged; D000419:Albuminuria / Q000150:complications; D002318:Cardiovascular Diseases / Q000150:complications; D002387:Cataract Extraction; D008076:Cholesterol, HDL / Q000097:blood; D003404:Creatinine / Q000097:blood; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000235:genetics / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000150:complications / Q000235:genetics / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D005838:Genotype; D006442:Glycated Hemoglobin / Q000032:analysis; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D006801:Humans; D006973:Hypertension / Q000150:complications; D007328:Insulin / Q000627:therapeutic use; D053685:Laser Therapy; D008136:Longevity; D008297:Male; D013959:Thyroid Diseases / Q000150:complications; D014280:Triglycerides / Q000097:blood
D008076:Cholesterol, HDL; D003404:Creatinine; D006442:Glycated Hemoglobin; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains; D007328:Insulin; D014280:Triglycerides