Diabetes Care, Vol 17, Issue 5 397-404, Copyright © 1994 by American Diabetes Association
Clinical characteristics of type II diabetic subjects consuming high versus low carbohydrate diets in Mexico City and San Antonio, Texas
C Gonzelez, MP Stern, BD Mitchell, RA Valdez, SM Haffner and BA Perez
Center for Diabetes Studies, American British Cowdray Hospital, Mexico City, Mexico.
OBJECTIVE--To compare the clinical status of type II diabetic subjects
identified in two population-based surveys, one performed in Mexico City,
Mexico and the other in San Antonio, Texas. RESEARCH DESIGN AND METHODS--In
a low income area of Mexico City, 3,517 age-eligible (35-64 years of age)
individuals were randomly selected of whom 3,319 were interviewed at home
and 2,198 were examined in a clinic (response rates 62.5%). In San Antonio,
2,357 similarly aged low-income Mexican Americans were randomly selected of
whom 2,076 were interviewed at home and 1,511 were examined (response rate
64.1%). Oral glucose tolerance tests were performed at both sites and
diabetes was diagnosed according to the World Health Organization (WHO)
criteria. In Mexico City, 288 type II diabetic individuals were identified,
and 255 were identified in San Antonio. The following variables were
measured: height, weight, subscapular and triceps skinfolds, waist-to-hip
circumference ratios (WHR), systolic and diastolic blood pressure (random 0
sphygmomanometer), fasting and 2-h postglucose load glucose and insulin
concentrations, and fasting total-cholesterol, HDL-cholesterol, and
triglyceride (TG) levels. A food frequency questionnaire was used to
estimate total calories and the percentage of calories derived from
protein, fat, and carbohydrate. Only type II diabetic patients were
included in the analyses. Age-adjustment was performed by analysis of
covariance for continuous variables and by the Mantel-Haenszel procedure
for discrete variables. RESULTS--The mean age, the percentage newly
diagnosed cases, and the percentage of males were similar in both sites.
The percentage of diabetic patients treated with oral agents was
significantly higher in Mexico City (56.9 vs. 72.7% in San Antonio and
Mexico City, respectively, P < 0.001), whereas the percentage treated
with insulin was significantly higher in San Antonio (18.8 vs. 2.1% for San
Antonio and Mexico City, respectively, P < 0.001). A significant
difference was observed in the percentage of calories derived from
carbohydrate (61.7-63.2 vs. 47.1-47.5% for Mexico City and San Antonio,
respectively, P < 0.001) and fat (18.4-20.0 and 30.1-33.0% for Mexico
City and San Antonio, respectively, P < 0.001). Body mass index (BMI)
was higher in San Antonio (27.6-30.4 vs. 30.2-32.9% for Mexico City and San
Antonio, respectively, P < 0.05). Total serum cholesterol was similar at
both sites. HDL cholesterol, however, was lower in Mexico City, both in
newly and in previously diagnosed patients (30.5-35.8 vs. 39.6-43.3 mg/dl
in Mexico City and San Antonio, respectively, P < 0.001). TG levels were
higher in Mexico City patients (187-249 vs. 167-179 mg/dl in Mexico City
and San Antonio, respectively, P < 0.001). The association between
diabetes and the anthropometric and metabolic variables was similar in
Mexico City and San Antonio with the following exceptions: Diabetes in
Mexico City was associated with less of an elevation in BMI, WHR, and
fasting insulin concentration and less of a reduction in the 2-h postoral
glucose load insulin concentration compared with diabetes in San Antonio.
In addition, although diabetes was associated with a lower HDL in San
Antonio subjects, no association appeared between diabetes and HDL in
Mexico City subjects. CONCLUSIONS--Diabetic subjects in Mexico City were
more likely to be treated with oral agents and less likely to be treated
with insulin compared with San Antonio patients. Previously diagnosed
diabetic subjects in San Antonio had higher BMIs than diabetic subjects in
Mexico City. Diabetic subjects in Mexico City ate less fat but more
carbohydrate than those in San Antonio. TG levels were higher and
HDL-cholesterol levels were lower in Mexico City diabetic subjects compared
with those in San Antonio. San Antonio diabetic subjects had lower HDL
levels than nondiabetic subjects but, in Mexico City, HDL levels were
similar in diabetic subjects and nondiabetic subjects...