For severe pneumonia in childhood, altitude and anemia matter

By MD Will Boggs

NEW YORK (Reuters Health) - Children who acquire severe pneumonia at high altitude fare worse than similar children at low altitude, especially if they have anemia, according to new research.

"Anemia is an under-recognized -- but preventable and treatable -- risk factor for poor outcomes in pneumonia among children living at high altitude," Dr. Peter P. Moschovis from Massachusetts General Hospital in Boston told Reuters Health by email. "Pending further trials, this may represent a target for treatment, either before an episode of pneumonia or during acute illness."

Anemia is not routinely assessed when treating pneumonia, and the effect of anemia and high altitude on pneumonia outcomes is not well described.

Dr. Moschovis and colleagues used data from the Severe Pneumonia Evaluation Antimicrobial Research (SPEAR) study to investigate the roles of altitude and anemia in disease severity and outcomes in 958 young children (age 2 to 59 months) with World Health Organization-defined severe pneumonia.

A fifth of the children (193) lived at high altitude, according to the report, online October 7 in Pediatrics. Their median hemoglobin was higher than that of the 765 children living at low altitude (10.3 g/dL vs. 10.0 g/dL, p<0.0001).

Severe hypoxemia was much more prevalent in children at high altitude (86%) than in children at low altitude (11%), as was cyanosis.

After adjusting for potential confounders, anemia on presentation was associated with a four-fold increase in treatment failure risk at high altitude; anemia did not predict treatment failure at low altitude.

The risk of treatment failure decreased by 35% with each 1 g/dL increase in hemoglobin. At high altitudes, the effect was greater in children with lower hemoglobin levels.

Children at high altitudes took much longer to recover to normoxemia (median, 5.25 days) than did children at low altitude (median, 0.75 days).

How might we improve pneumonia outcomes in these children? "This is an area that has not yet been fully investigated, but is a focus of ongoing research by our group," Dr. Moschovis said. "To begin with, practitioners might focus on anemia prevention by ensuring access to clean drinking water, deworming, and adequate iron intake."

"Prevention and treatment of anemia should be a high priority in young children living at high altitude, and addressing this risk factor could reduce morbidity and mortality from severe pneumonia," the researchers conclude. "Further study is needed to determine the optimal strategies for preventing and treating anemia in the setting of pneumonia."

SOURCE: http://bit.ly/19LZUPL

Pediatrics 2013.