Chronic mountain sickness, optimal hemoglobin, and heart disease

Area of Science:

• High-altitude medicine
• Cardiology
• Pulmonology

Background:

• Chronic mountain sickness (CMS) is a significant health issue for males residing in high-altitude regions like La Paz, Bolivia.
• Despite extensive research since its 1925 description, the exact onset and causes of CMS remain unclear.
• Elevated hemoglobin concentrations appear unfavorable for high-altitude acclimatization.

Purpose of the Study:

• To review the current understanding of chronic mountain sickness (CMS) in high-altitude dwellers.
• To discuss the concept of "optimal" hemoglobin and hematocrit levels for acclimatization.
• To outline common congenital and acquired heart diseases prevalent in high-altitude populations, including chronic cor pulmonale.

Main Methods:

• Literature review and synthesis of existing research on CMS.
• Discussion of theoretical "optimal" hemoglobin concentrations.
• Analysis of epidemiological data on heart diseases in high-altitude regions.

Main Results:

• The hypothesis of an "optimal" hemoglobin concentration (e.g., 14.7 g/dL for Andean men) is considered theoretical and not practically applicable.
• Common congenital heart diseases include patent ductus arteriosus, atrial septum defect, and ventricle septum defect.
• Acquired heart conditions such as rheumatic valve disease, Chagas disease, and chronic cor pulmonale due to pulmonary hypertension are frequent.

Conclusions:

• Excessively high hemoglobin levels are detrimental to high-altitude acclimatization.
• A range of congenital and acquired heart diseases, particularly chronic cor pulmonale, are associated with CMS and high-altitude living.
• Further research is needed to fully elucidate the causes and management of CMS.