Diabetic retinopathy at high altitude.

The objective of this study was to determine whether altitude hypoxia favors the development of diabetic retinopathy (DR) in healthy type 1 diabetic climbers with tight glycemia control. The retinas of 7 type 1 diabetic climbers with a history of stays at high altitude were studied through nonmydriatic chamber retinography (Ffo-CNM). The retinographies were performed before and after a 7,143 m peak expedition. One of the subjects presented evidence of DR prior to the ascent, in addition to a microhemorrhage afterward; the rest of the retinographies were normal. Fine glycemia management and adequate acclimatization are not the only cautions for diabetics going to altitude; an ophthalmologic exam beforehand is also recommended.