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Diabetic retinopathy at high altitude.
Conxita Leal1, Jordi Admetlla, Ginés Viscor
1Institut d'Estudis de Medicina de Muntanya (IEMM), Barcelona, Spain. cleal@camfic.org
High Altitude Medicine & Biology
|March 12, 2008
Summary
Altitude hypoxia did not appear to worsen diabetic retinopathy (DR) in type 1 diabetic climbers with controlled blood sugar. However, an ophthalmologic exam before high-altitude travel is recommended for diabetics.
Area of Science:
- Ophthalmology
- Altitude Medicine
- Diabetology
Background:
- Diabetic retinopathy (DR) is a microvascular complication of diabetes.
- High altitude exposure presents physiological challenges, including hypoxia.
- The impact of altitude hypoxia on DR in well-controlled type 1 diabetes is not well understood.
Purpose of the Study:
- To investigate if altitude hypoxia promotes the development or progression of diabetic retinopathy.
- To assess the ocular health of type 1 diabetic individuals during high-altitude expeditions.
Main Methods:
- Studied 7 type 1 diabetic climbers with prior high-altitude experience and tight glycemic control.
- Utilized nonmydriatic chamber retinography (Ffo-CNM) for retinal imaging.
- Performed retinal examinations before and after ascending a 7,143 m peak.
Main Results:
- One participant had pre-existing DR and developed a microhemorrhage post-expedition.
- Retinographies for the other six participants remained normal.
- No significant worsening of diabetic retinopathy was observed in the group.
Conclusions:
- Altitude hypoxia may not directly favor DR development in type 1 diabetics with strict glycemic management.
- Standard precautions for diabetics at altitude should include pre-expedition ophthalmologic evaluation.
- Further research is warranted to fully elucidate the relationship between hypoxia and diabetic eye disease.
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