14 January 2006

Iron Supplementation and Malaria

An interesting study by Johns Hopkins University physician Robert Black published in the current Lancet issue suggests that it may not be a good idea to give iron supplements to iron-deficient children with malaria.
Midway through the trial, the iron and folic acid-containing groups had to be stopped because they were associated with higher rates of adverse events (hospital admissions and deaths) than the zinc and placebo groups, which have been continued. The 12 percent higher rate of serious adverse events noted after supplementation with iron and folic acid calls into question the current global recommendations on the use of these supplements to prevent iron deficiency.

[From the Discussion part of the study - Effects of routine prophylactic supplementation with iron and folic acid on admission to hospital and mortality in preschool children in a high malaria transmission setting: community-based, randomised, placebo-controlled trial, Lancet 2006; 367:133-143, 14 Jan 2006]

IDA_Philippines Relating this to the Philippine setting, we all know that there are certain regions in the Philippines which are endemic for malaria (see related post - malaria in the Philippines posted last year).

But how many children with iron deficiency anemia (IDA) live in this malaria-endemic areas?

The data on the left was sourced out from the Food and Nutrition Research Institute, and dated October, 2000. I know. It is a bit outdated. But we make do with what is available. The present picture may always be worse than what is shown here.

As you can see, there's a high prevalence of IDA in Cagayan Valley, Eastern Visayas, and the ARMM region. Those who live in the Ilocos and Western Mindanao areas come second highest.

Superimposing the 2 significant maps we find here (for malaria) and here (for iron-deficiency anemia), we find that those children who are particularly at risk in the Philippines live in the ARMM, Western Mindanao, and Cagayan Valley regions.

I think local health authorities should do a study to validate Dr Black's findings in the mentioned study. His study is a good starting point.

Why is iron supplementation bad for children with both malaria and iron-deficiency anemia?

Even Dr Black is puzzled:
"It appears that there is an adverse affect of giving iron in this setting, perhaps related to the stimulation of the bone marrow to produce red blood cells that are then more readily infected with the malaria parasite," he said. "Or perhaps there is a direct toxic effect of the iron that has been hypothesized, but the exact mechanism has not been worked out."

[VOA News, 13 Jan 2006 ]

2 reactions:

bayibhyap said...

What about dengue? A dengue patient's red blood cells fall rapidly, if I am not mistaken? Is an iron supplement recommended in the case of dengue patients?

Dr. Emer said...

That's correct, Bayi. But there has been no study (none that I know of) of a similar nature done with Dengue or its hemorrhagic variant.