[Obesity and leptin association in three Chilean aboriginal populations].
BACKGROUND
Although there is a clear relationship between body mass index and leptin levels, few authors have addressed the possible influence of ethnic factors on these levels.


OBJECTIVE
To measure serum leptin in three different Chilean aboriginal populations.


METHODS
Fasting serum leptin and insulin levels were measured by radioimmunoassay in 345 rural mapuche individuals, 247 rural aymara subjects and 162 urban mapuche subjects. A body mass index of 27.5 kg/m2 was used as cutoff point to classify study subjects.


RESULTS
Among the three ethnic groups, women had serum leptin levels three times higher than men. In all three ethnic groups, there was a significant association between leptin levels, body mass index and gender (r2 = 0.32 and 0.5 p < 0.001, in rural mapuche, r2 = 0.32 and 0.5 p < 0.001, in aymara and r2 = 0.24 and 0.49, p < 0.001 in urban mapuche populations). No differences in leptin levels were observed for the interaction between age and insulin. The increments per quartile in leptin levels were lower among mapuche than aymara individuals.


CONCLUSIONS
Rural mapuche individuals have a high frequency of obesity. However their leptin levels are lower than those of aymara or urban mapuche populations. The higher leptin levels observed in urban mapuche subjects could be due to environmental influences.
Pérez
F
F
Unidades de Biología Molecular y Epidemiología Nutricional, INTA, Universidad de Chile, Santiago, Chile. fperez@uec.inta.uchile.cl
Santos
J L
JL
Albala
C
C
Calvillán
M
M
Carrasco
E
E
D000328:Adult; D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D002677:Chile / Q000208:ethnology; D005260:Female; D006801:Humans; D007199:Indians, South American; D007328:Insulin / Q000097:blood / Q000378:metabolism; D020738:Leptin / Q000097:blood* / Q000378:metabolism; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000150:complications / Q000453:epidemiology; D012423:Rural Health; D012737:Sex Factors
D007328:Insulin; D020738:Leptin