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OBJECTIVE The importance of renin-angiotensin-aldosterone system (RAAS) activation in retinopathy for long-standing diabetes is not well understood. We determined retinopathy stage and evaluated associations with other vascular complications before and after physiological RAAS activation in adults with long-standing (≥50 years duration) type 1 diabetes. RESEARCH DESIGN AND METHODS Participants underwent retinal examination by digital funduscopic photography and optical coherence tomography and were classified as having nonproliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR), or no diabetic retinopathy (NDR) with or without diabetic macular edema (DME). Neuropathy was measured by clinical neuropathy examination scores, electrophysiologically, and by corneal confocal microscopy. Renal function was measured by inulin and para-aminohippurate clearance methods. Arterial stiffness was measured by applanation tonometry. Renal function, blood pressure, and arterial stiffness were measured before and after RAAS activation with angiotensin II (ANGII). Associations were determined using linear regression. RESULTS Twelve (16%) of the 75 participants had NDR, 24 (32%) had NPDR, and 39 (52%) had PDR. A low overall prevalence of DME (4%) was observed. Those with PDR had worse nerve function and reduced corneal nerve density, were more likely to have macrovascular disease, and had increased arterial stiffness in response to ANGII compared with those with NPDR or NDR. Prevalence of kidney disease or renal hemodynamic function did not differ by retinopathy status. CONCLUSIONS PDR was associated with neuropathy severity and cardiovascular and peripheral vascular disease. In those with PDR, RAAS activation may be linked to vascular stiffening, an effect that persists in long-standing type 1 diabetes.

Objective The incidence of giant cell arteritis (GCA) is insufficiently documented for Canada, but important to ascertain for public health planning. We estimate the incidence of biopsy-proven GCA (BPGCA) in Kingston, Ontario, and for the province of Ontario. Method The number of cases of BPGCA was tabulated from retrospective chart review of all temporal artery biopsies (TABx) in Kingston, Ontario from 2011–15. The relevant population denominator was determined from the Canada census federal electoral district and the patient’s postal code. The province-wide estimate for the incidence of BPGCA was calculated from provincial billing data of TABx from 2015–17, the Canada census for Ontario, and the expected positive yield of TABx. Results There were 35 subjects with BPGCA in the Kingston area over the 4-year period, from a population of 179 503 individuals 50 years of age or older (≥50 years). Ontario billing data identified 2404 patients who underwent TABx for suspected GCA over a 2-year period, from a population of 5 143 610 persons ≥50 years. Meta-analysis of 5 provincial TABx series suggested a 21% positive yield from TABx procedures (95% CI 0.18–0.24). The minimum cumulative incidence of BPGCA was 4.9 per 100 000 persons ≥50 years in Kingston, and 4.9 (95% CI 4.2–5.6) per 100 000 persons ≥50 years for Ontario as a whole. Conclusion The estimated incidence of BPGCA in Ontario using 2 different estimation techniques was comparable, but low compared with other countries. The actual incidence of GCA in Ontario may be higher.

Objective To evaluate the screening rates for diabetic pediatric patients in a regional center according to the Canadian Diabetes Association guidelines. Design Retrospective study. Participants The study consisted of 82 patients seen in the pediatric diabetes clinic at Peterborough Regional Health Center. Methods Medical records for all pediatric patients with diabetes were reviewed between July 2016 and February 2017. Parents and children were surveyed on details of their ocular examination history. Logistic regression analysis was conducted to evaluate if any characteristics were associated with noncompliance to Canadian Diabetes Association guidelines. Results The average age of the patients in our study was 12 years old with a mean duration of diabetes of 4 years. The majority of patients had type 1 diabetes (n = 79/82, 96.3%) and the mean HbA1c level was 9.1. Only 16 patients (19.5%) adhered to the Canadian Diabetes Association guidelines for diabetic retinopathy screening. Of the 66 patients who did not comply with the guidelines, 65 (98.5%) had received more exams than recommended under their respective screening guidelines. All dilated eye examinations were normal, and no diabetic retinopathy was found. Statistical analysis revealed that the duration of diabetes may be a predicting factor of noncompliance to the guidelines (–0.2488, 95% CI –0.505, –0.042). Conclusions This study shows a low compliance rate with screening guidelines in our diabetic pediatric population. Of interest, the low compliance in this cohort was related to excessive eye exams. This study also found a low incidence rate of diabetic retinopathy despite poor management of diabetes, similar to previous studies of pediatric diabetic eye disease.