Weight, physical activity, and smoking as determinants of insulinemia in adolescents.

BACKGROUND: It is known that insulinemia is the result of the interaction among several factors, such as weight, body fat pattern distribution, and physical activity as well as ethnicity. There is little information regarding this question among Mexican adolescents. The association among fasting insulin levels, weight, fat distribution, physical activity, and cigarette smoking was studied in Mexican adolescents. METHODS: Cross-sectional data were collected from 352 Mexican adolescents aged 14-19 years (response rate 41.5%). Fasting insulin levels were measured by microparticle enzyme immunoassay; body mass index (BMI), waist-to-hip ratio (WHR), and waist circumference (WC) were determined using standardized techniques, while physical activity was determined by 7-day Stanford physical activity inventory. Cigarette smoking was defined as number of cigarettes/year. RESULTS: Increased BMI and waist circumference, low physical activity, younger age, and non-smoking were associated with high insulin levels. Non-smokers had higher fasting insulin levels compared to smokers (57.8 pmol +/- 1.84 vs. 49.7 pmol/L +/- 2.8; p = 0.034). However, adjusted odds ratio (OR) between insulin and smoking status was not significant. Multivariate analysis showed the following: insulin increased 1.06 pmol/L for each unit of change in BMI; increased 1.02 pmol/L for each unit of change in waist circumference; increased 1.16 pmol/L for non-smoking, and decreased 1.07 pmol/L for each 250 kcal/day of energy expenditure. CONCLUSIONS: Our results support the concept that Mexican adolescents who are overweight have abdominal fat distribution and physical inactivity, and significant hyperinsulinemia. The relationship between smoking and lower insulinemia found in this research warrants further study.

[Prevalence of diabetes mellitus and hyperlipidemia among Otomi indians]. / Prevalencia de diabetes mellitus e hiperlipidemias en indígenas otomíes.

OBJECTIVE: To determine prevalence and risk factors for diabetes mellitus (DM) and hyperlipidemias in a population of Otomi Indians. MATERIAL AND METHODS: A cross-sectional study was conducted between 1996 and 1997, in a convenience sample of 91 Otomi Indians, aged 15 to 77 years, in the communities of Yosphi and El Rincon, Queretaro, Mexico. Fasting blood samples were obtained to measure glucose, cholesterol and triglyceride levels. RESULTS: DM was found in 4.4% of subjects; hypercholesterolemia in 7.6%; and hypertriglyceridemia (HTG) in 26%. Mean concentrations of glucose -(81.0 +/- 24.4 mg/dl) and triglycerides (157.4 +/- 88.9 mg/dl) increased significantly with age, p = 0.0279 and p < 0.0001, respectively; as well as the prevalence of HTG (p < 0.0001). CONCLUSIONS: Results suggest that drastic changes in the diet of Otomi Indians may cause severe problems related to high concentration of lipids in blood.

Relation of serum cholesterol, lipid, serotonin and tryptophan levels to severity of depression and to suicide attempts.

OBJECTIVE: To determine if there is a relation to low serum cholesterol, lipoprotein, serotonin or tryptophan levels in patients with depression who have recently attempted suicide. DESIGN: Biochemical and behavioural study. SETTING: Inpatient and outpatient treatment at the Instituto Mexicano de Psiquiatría. PARTICIPANTS: Thirty-three patients with a diagnosis of major depressive episode. Eighteen of these patients had attempted suicide in the month before the start of the study; 15 patients had never attempted suicide. OUTCOME MEASURES: Serum levels of total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, serotonin (5-HT) and tryptophan. Scores on Hamilton Depression Rating Scale, Carroll Depression Rating Scale, Beck Hopelessness Scale and Beck Suicide Attempt Severity Scale. RESULTS: There were no significant differences between patients who had attempted suicide and those who had not in terms of serum cholesterol, HDL, LDL and triglyceride levels. Serum levels of 5-HT and tryptophan were significantly lower in patients with depression who had a recent suicide attempt than in those patients who had never attempted suicide. A comparison of patients not taking antidepressant medication found serum 5-HT levels to be more than 3 times lower in those patients with a recent suicide attempt than in patients with no history of suicide attempt. CONCLUSIONS: The study found no difference in lipid profiles between patients who had attempted suicide and those who had not. Low serum levels of 5-HT may increase the risk of suicide attempt in patients who are depressed.

Vitamin E modifies neither fructosamine nor HbA1c levels in poorly controlled diabetes.

OBJECTIVE: To examine the effects of vitamin E on total serum protein glycation (fructosamine), hemoglobin glycation (HbA1c), and serum levels of glucose, total cholesterol, triglycerides, LDL-C, HDL-C, apolipoprotein A1 and apolipoprotein B. MATERIAL AND METHODS: Sixty poorly controlled diabetic patients were randomly assigned to receive either 1200 mg/day of vitamin E or identical placebo capsules during a two month period following a double blind cross-over design with a four week wash-out period between regimens. RESULTS: Seven patients were excluded from the study because of reasons not related to the medication. In the remaining 53 patients, the levels of serum glucose, fructosamine, HbA1c, total cholesterol, HDL-C, LDL-C, Apo A1 and Apo B did not vary significantly with vitamin E as compared with placebo. CONCLUSIONS: No significant effects of vitamin E on any of the parameters evaluated were observed in poorly controlled diabetic patients.