Relationship of blood pressure to retinal vessel diameter in type 1 diabetes mellitus

• Published in: Archives of ophthalmology (1960) Vol. 128; no. 2; p. 198
• Main Authors: Klein, Ronald, Myers, Chelsea E, Klein, Barbara E K, Zinman, Bernard, Gardiner, Robert, Suissa, Samy, Sinaiko, Alan R, Donnelly, Sandra M, Goodyer, Paul, Strand, Trudy, Mauer, Michael
• Format: Journal Article
• Language: English
• Published: United States 01-02-2010
• Subjects: Adolescent; Adult; Angiotensin II Type 1 Receptor Blockers - pharmacology; Angiotensin-Converting Enzyme Inhibitors - pharmacology; Arterioles - physiology; Blood Pressure - drug effects; Blood Pressure - physiology; Blood Pressure Monitoring, Ambulatory; Circadian Rhythm; Diabetes Mellitus, Type 1 - physiopathology; Double-Blind Method; Enalapril - pharmacology; Female; Glycated Hemoglobin - analysis; Heart Rate; Humans; Image Processing, Computer-Assisted; Losartan - pharmacology; Male; Middle Aged; Retinal Vessels - drug effects; Retinal Vessels - physiology; Venules - physiology
• ISSN: 1538-3601
• DOI: 10.1001/archophthalmol.2009.391

To examine the relationship of blood pressure (BP) and use of angiotensin-receptor blocker or angiotensin-converting enzyme inhibitor to retinal vessel diameter in normotensive, normoalbuminuric persons with type 1 diabetes mellitus.
In a randomized, controlled clinical trial, clinic and 24-hour ambulatory BPs were measured in persons with type 1 diabetes mellitus and gradable fundus photographs both at baseline (n = 147) and at 5-year follow-up (n = 124). Retinal arteriole and venule diameters were measured by a computer-assisted technique. Individual arteriole and venule measurements were combined into summary indexes that reflect the average retinal arteriole (central retinal arteriole equivalent [CRAE]) and venule (central retinal venule equivalent [CRVE]) diameter of an eye, respectively.
While controlling for age, study site, glycosylated hemoglobin level, and ambulatory pulse rate, the daytime ambulatory systolic (-0.29-microm effect per 1 mm Hg; P = .02), daytime ambulatory diastolic (-0.44-microm effect per 1 mm Hg; P = .04), nighttime ambulatory systolic (-0.27-microm effect per 1 mm Hg; P = .03), and 24-hour ambulatory systolic (-0.31-microm effect per 1 mm Hg; P = .03) BPs were cross-sectionally associated with a smaller CRAE. While controlling for age, study site, glycosylated hemoglobin level, ambulatory pulse rate, and baseline CRAE, no BP measure was associated with a change in CRAE or CRVE during 5 years of follow-up. Treatment with losartan potassium or enalapril maleate was not associated with a statistically significant change in CRAE or CRVE.
Angiotensin-converting enzyme inhibitor or angiotensin-receptor blocker therapy does not affect retinal arteriole or venule diameter in normotensive persons with type 1 diabetes mellitus. Trial Registration clinicaltrials.gov Identifier: NCT00143949.