Surgery and Healing in the Developing World - Dartmouth-Hitchcock

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316 Surgery and Healing in the Developing World
insulin-like growth factor-I (IGF-I) levels among the Efe, less than half the values
for either Lese or Azande. This growth factor IGF-I as well as TSH are low in Efe,
and each has implications speculated upon as the reason for diminished stature among
Efe. 1 It may also mean that IGF-I is a required cofactor for goitrogenesis, which Efe
have less of than Lese, and both express less than Azande. 55-57 Azande, except for
those who are cretins, have a height and stature comparable to other Bantu populations
in Central Africa.
The Efe may have evolved a cultural means of mitigating hypothyroidism through
an interdependence which furnishes a greater variety of micro- and macronutrient
food resources. 58 Reliance on a monoculture, particularly one that is low in calories,
profoundly deficient in iodine, iron, selenium, vitamin A and protein, and contains
a goitrogen that may be further concentrated in its preparation, renders the Azande
peoples within this study population vulnerable to hypothyroidism.
The Efe interdependency with Lese may give them a greater variety of food
resources than the Azande experience. The lower rates of hypothyroidism and goiter
observed within the Lese than the Azande demonstrate may reflect the greater variety
of food resources, including enough iodine to bring their thyroid hormone levels
up to nearby Efe levels (Table 3) but through the hypothyroidism-induced compensatory
mechanism of goiter incidence in one-third of the Lese. The Lese may either
be more dependent on cassava foodstock and its goitrogen potential than Efe, or the
Efe, if they have a comparable cassava intake as Lese do, are selectively spared by the
combination of low TSH and IGF-I factors for goitrogenesis.
Although each of the three populations lives in an iodine-deprived environment,
only the Azande are nearly exclusively dependent on cassava with its goitrogen and
the Azande demonstrate both extremely high TSH and normal IGF-I with resultant
nearly uniform goitrogenesis. The Efe may lack one of the factors necessary for
predictable goiter formation in the low IGF-I levels they exhibit, even if they were
exposed to goitrogens and depended on a less varied source of caloric intake.
Conclusion
Changing one aspect within this ecologic adaptation—namely micronutrient
iodine repletion—without modifying means to improve nutrition in macro- and
other micronutrient sources constitutes a further maladaptive stress upsetting the
marginal benefit of low energy utilization and requirements.
When evaluating the effect on an individual of iodine repletion in the correction
of hypothyroidism, medical intervention seems to have a very obvious and overwhelmingly
positive beneficial consequence with exceptions that are considered complications.
When viewed from the perspective of the society of which these individuals
are a part, the negative consequences of medical intervention in hypothyroidism
become more prominent.
Spokespersons for the Azande population under study—-including those not
involved as participants such as Chief Sasa-—are uniformly appreciative of the medical
intervention program in hypothyroidism when viewing the results in individual
lives. But they have expressed increasing complaints about the circumstances of their
poverty, environmental degradation, crowded conditions, hunger, restlessness, not
interpreted as related in any way to the hypothyroidism intervention, though coincident
in onset.
In much the same way as evaluation of morphologic consequences of intervention
in an iodine-deficient population can have beneficial, detrimental and surprising
consequences, (e.g., goiter regrowth through some other mechanism in escape