[The problem of obesity and its shocking characteristics in Chile]

Obesity is a disease which severely affects health associated to an increase in relative mortality. The measurement of obesity is currently performed by means of the Body Mass Index (BMI). Normal BMI values are between 20 and 24.9 kg/m2. In obese individuals a central fat distribution is associated with an increased mortality in men and probably in women when compared with a peripheral distribution. Based on studies carried out in the Metropolitan Region (Greater Santiago) in 1992, it is estimated that the prevalence of obesity in the population is near 20% in men and 40% in women, with the highest prevalence being observed in women from a low socioeconomic level. The projection of these figures to the whole country gives an estimate of 2.5 million people in Chile with an increased risk of mortality due to obesity. Since there is a lack of awareness in the Chilean population of the pathology of obesity and its consequences, the implementation of programs of prevention and treatment of this disease lead by the health authorities is of paramount importance.

[Immunologic and insulin secretion markers in non insulin dependent diabetic patients with secondary failure to oral hypoglycemic drugs]

BACKGROUND

The pathogenesis of secondary failure to hypoglycemic agents is heterogeneous. Some patients are true insulin dependent diabetics with a slow autoimmune disease suggested by their positive islet cell antibodies. Others, have an increased insulin resistance.

AIM

To assess the frequency of positive islet cell antibodies in diabetic patients with secondary failure to oral hypoglycemic agents.

PATIENTS AND METHODS

Thirty one diabetics, 16 with recent (less than six months) secondary failure and 15 with metabolically stable non insulin dependent diabetes were studied. All patients were older than 25 years old and had a body mass index of less than 30 kg/m2. C peptide levels before and at 5, 15 and 30 min after IV glucagon, islet cell antibodies using the Poly Human IgG peroxidase method and insulin sensitivity and secretion (estimated by the Homeostasis Model Assessment) were measured.

RESULTS

Patients with secondary failure had lower C peptide levels, compared to subjects with stable diabetes (basal: 1.5 +/- 0.2 and 2.8 +/- 0.2 ng/ml; 5 min: 2.4 +/- 0.3 and 5.5 +/- 0.5 ng/ml; 15 min: 1.9 +/- 0.3 and 4.0 +/- 0.6 ng/ml; 30 min: 1.6 +/- 0.3 and 3.4 +/- 0.5 ng/ml). Beta cell activity was 20.6 +/- 4.3% in patients with secondary failure and 92.2 +/- 9% in stable diabetics (p < 0.01). Insulin sensitivity was similar in both groups (48.6 +/- 6 and 42.8 +/- 3.5% respectively). Three patients with secondary failure and none with stable diabetes had positive islet cell antibodies. When comparing patients with secondary failure and positive antibodies and subjects with secondary failure and negative antibodies, the former had non significantly lower age, BMI and C peptide levels.

CONCLUSIONS

Some diabetic patients with secondary failure have positive islet cell antibodies. They should be measured in these patients to start insulin treatment precociously.

[Indicators of atherosclerosis risk. Evaluation with coronary angiography in non diabetic men with total cholesterol levels equal to or below 240 mg/dl]

We studied 90 male non diabetic patients aged between 40 and 65 years old with a total cholesterol of less than 240 mg/dl and not receiving cholesterol reducing drugs, that were subjected to elective coronary arteriography. Weight, height, blood pressure and smoking habits were recorded and a fasting blood sample was drawn to measure total and HDL cholesterol, triglycerides, apoproteins A1 and B, Lipoprotein(a) and plasma cholesteryl ester transfer activity. Arteriography disclosed coronary lesions in 54 patients. Compared to patients without lesions, the former had lower HDL cholesterol (34 +/- 9.8 vs 40.2 +/- 11.6 mg/dl) and higher total cholesterol/HDL cholesterol and apoB/apoA1 ratios. No differences were found for lipoprotein(a) and plasma cholesteryl ester transfer activity. Univariate analysis showed that low HDL cholesterol had the best predictive capacity for atherosclerosis.

[Is lipoprotein (a) a risk factor for coronary disease?]

The serum level of Lp(a) ha been defined in retrospective and cross sectional studies as an independent risk factor for acute myocardial infarction and cerebrovascular thrombotic accidents. However, recent prospective studies have found no evidences of association between Lp(a) levels and risk of myocardial infarction, therefore, current knowledge does not support the measurement of Lp(a) as a screening tool among middle age men. Further research is needed, to identify specific groups where Lp(a) may be a risk factor.

[Non-insulin-dependent diabetics with secondary failure: insulin therapy at bedtime combined with glibenclamide]

Secondary failure and the requirement is common in patients with non-insulin dependent diabetes mellitus. The combination of sulfonylureas with NPH insulin at bedtime has been proposed to avoid high doses of insulin. We treated 18 patients (2 men, age range 47-76 yr) non respondent to diet and glibenclamide, combining NPH insulin in an average dose of 0.3 +/- 0.03 U/kg BW at bedtime for 6 months. Fasting serum glucose improved from 256 +/- 11 to 132 +/- 6 mg/dl and HbA1C from 13.6 +/- 0.4 to 9.9 +/- 0.2%. Four patients achieved a good control (defined as a HbA1C < 9), 9 a fair control (HbA1C 9.1-10) and 5 persisted with a bad control (HbA1C > 10). Well controlled patients were younger, had a shorter duration of diabetes and had a non significantly higher body mass index. Fasting serum insulin and C peptide levels achieved after glucagon injection were not predictors of the metabolic response to combined therapy. Tolerance to treatment was good, without changes in blood pressure or serum lipids and with a low incidence of hypoglycemia. There was a mean increase of 3.6 kg in body weight. After 6 months of therapy, maximum achieved C peptide values after glucagon increased from 3.3 +/- 0.3 to 4.5 +/- 0.4 ng/ml. It is concluded that combined glibenclamide and NPH insulin at bedtime is useful to treat secondary failure in non-insulin dependent diabetic patients, but their response in variable and non dependent on their beta insular secretion.

[Dyslipidemic patients with coronary cardiopathy. Effect of different doses of OMEGA-3 fatty acids on serum lipids and lipoproteins]

Twenty one male patients aged 35 to 70 years, with coronary artery disease and dislipidemia refractory to dietary treatment, were assigned to three parallel groups of 7 individuals each that received a supplemental dose of 2, 4 and 6 g/day of omega-3 fatty acids during 60 days. After a 30 days wash-out period and 60 of supplementation, subjects were weighed, a dietary survey was performed, serum levels of total cholesterol and triglycerides, the lipid content of serum lipoproteins and the content of EPA+DHA in plasma phospholipids were measured. A dose dependent increase in EPA+DHA content of phospholipids and no changes in weight or nutrient intake were observed during the supplementation period. With the 6 g dose, a significant reduction in total cholesterol, with a reduction in VLDL and increase in LDL cholesterol and a decline in VLDL triglycerides was observed. With the 4 g dose a reduction in total cholesterol at the expense of VLDL and HDL cholesterol and a reduction in VLDL triglycerides but no changes in total triglycerides was observed. No changes in serum lipids were observed with 2 g dose. In patients with type IIA hyperlipidemia, a significant positive correlation was observed between DHA+EPA content of plasma phospholipids and LDL cholesterol, this correlation was not observed in patients with IIB or IV phenotypes. It is concluded that omega-3 fatty acids are ineffective as the only treatment for dislipidemias refractory to diet.

[The effect of body weight change on cardiovascular risk factors]

Changes in cardiovascular risk factors and body weight were correlated in 568 professional males from 17 to 57 years of age. Measurements of weight, height, body mass index, blood pressure and fasting levels of blood sugar, triglycerides, total and HDL cholesterol were obtained in 1980 and again in 1985. A significant correlation was found between body mass index and blood pressure, total cholesterol, total/HDL cholesterol, HDL cholesterol (p < 0.005), triglycerides (p < 0.001) and blood sugar (p < 0.05). Changes in body weight during the study period were correlated to changes in total cholesterol (p < 0.001), triglycerides (p < 0.05) and diastolic blood pressure (p < 0.005). Thus, obesity is correlated to the presence of cardiovascular risk factors. Its modification may influence development of atherosclerotic cardiovascular disease.

[Effect of dietary polyunsaturated fatty acids on the content and metabolism of glutathione in rat kidney]

The effect of dietary polyunsaturated fatty acids (PIFA) upon the content of reduced glutathione (GSH) of the kidney was studied in 32 male Wistar rats. Two equal size groups were fed diets supplemented with either 10% or 18% corn oil. Sixteen hours before death, half of each experimental group was submitted to fasting. The content of GSH and the activity of gamma glutamyl transpeptidase (GGTP) and gamma glutamyl cysteine synthetase was determined in kidney tissue. Fasting led to a reduction of GSH from 3.21 +/- 0.54 to 1.25 +/- 0.20 mumol per gm in the group fed 10%. PIFA. Equivalent figures for the group fed 18% PIFA were 3.49 +/- 0.54 and 0.49 +/- 0.08, respectively. GGTP activity increased significantly after fasting but no differences were observed according to level of PIFA intake. The exaggerated reduction of GSH during fasting after a high PIFA intake may expose the animals to risk of cell damage induced by peroxides or other oxidating agents.

[Insulin sensitivity: absence of sexual differences when expressed as a function of lean body mass]

The hyperinsulinemic, euglycemic clamp technique was used to test the hypothesis that--when expressed per kilogram of lean body mass--there is a sex-difference in peripheral insulin-mediated glucose disposal (M), as proposed in the literature. Lean body mass was assessed with tetrapolar bioelectric impedance analysis. We studied 15 normal subjects (volunteers with normal glucose tolerance and body mass indices between 20-25 kg/m2) of both sexes, 9 women and 6 men, of 2 age-groups, 20-30 year-old and 40-50 year-old. Men and women were similarly aged (33.3 +/- 3.8 and 33.3 +/- 3.8 years, respectively). Body mass indices were similar in both sexes (22.5 +/- 0.6 in women and 23.6 +/- 0.7 in men, NS) but percentages of fat mass were not (29.4 +/- 1.2 in women and 20.6 +/- 1.6 in men, p less than 0.001). As no difference in M (mg of glucose metabolized per kilogram of body weight per minute) between age-groups was found (6.4 +/- 0.8 and 6.8 +/- 1.2 mg/kg/min, NS) the data from these 2 age-groups were pooled. When M values obtained in both sexes were compared no differences were found (7.1 +/- 1.5 mg/kg/min in women and 6.3 +/- 0.6 in men, NS). Similarly, when M was expressed in function of the prevailing insulin levels attained during steady-state, M/l, no differences were disclosed (8.98 +/- 2 mg/kg/min/microIU insulin in women and 7.8 +/- 1.2 in men, NS).(ABSTRACT TRUNCATED AT 250 WORDS)

[The effect of a peripheral androgenic blockade on plasma lipoproteins in hirsutism patients]

We studied the effect of flutamide, a peripheral androgenic blocking agent, 500 mg daily for 28 days in 7 non ovulating patients with hirsutism. Total and HDL cholesterol, triglycerides, testosterone and dehydroepiandrosterone sulphate (S-DHEA) plasma levels were measured in patients and in 6 non ovulating control women of similar age and weight. Only basal HDL levels were lower in patients than in controls (40.2 +/- 1.6 vs 51.4 +/- 3.3 mg/dl, p < 0.01). A decrease in S-DHEA levels was observed after flutamide in patients with hirsutism (3.2 +/- 0.4 to 2.1 +/- 0.4, p < 0.01) which may be attributed to the lowering of cortisol clearance induced by the drug. Total testosterone and plasma lipoproteins remained stable. Thus, peripheral androgenic blockade does not modify the decreased levels of HDL cholesterol in non ovulating patients with hirsutism.

[Alcohol and the risk factors of coronary cardiopathy. A study in 571 men]

In 571 healthy professional males we correlated alcohol consumption with serum total cholesterol (C), HDL-C, triglycerides, blood sugar, cigarette consumption, body mass index and arterial blood pressure. An outstanding finding was a positive independent, correlation of alcohol consumption and serum HDL-C levels (r 0.22, p < 0.0001). Univariate analysis showed correlation of alcohol consumption with body mass index, blood pressure and total serum C, however this was dependent on age and/or body mass. No correlation was found between alcohol consumption and blood sugar or TG levels. Alcohol consumption did not identify a group of subjects with high risk factors. Consumption of more than 10 cigarettes per day decreased the strength of the association between elevated HDL levels and alcohol consumption. We conclude that a moderate intake of alcohol is associated to increased serum HDL levels with no significant change of other coronary risk factors.

[Cholestyramine in the treatment of hypercholesterolemia. Our experience in 11 cases]

Bile acid sequestrant resins are considered agents of choice in the therapy of hypercholesterolemia non responsive to diet treatment. We evaluated the effects of cholestyramine, 12 g per day during 4 weeks, in 11 adult patients with severe hypercholesterolemia. Total cholesterol decreased from 414 +/- 112 to 302 +/- 140 mg/dl (28%), LDL cholesterol from 330 +/- 122 to 226 +/- 143 (33%) and Apo B lipoprotein from 141 +/- 31 to 115 +/- 34 mg/dl (18%), p < 0.01. HDL cholesterol including fractions HDL2 and HDL3, Apo A1 and Triglyceride levels were not modified. No significant side effects on gastrointestinal function were observed. Thus, we confirm that cholestyramine is an effective therapy for severe hypercholesterolemia.

[Diabetes mellitus in chronic alcoholic liver damage]

We performed an oral glucose tolerance test and measured serum insulin levels in 38 patients with chronic alcoholic liver damage. A diabetic curve was obtained in 34% of subjects both obese and non obese. Insulin levels were elevated in comparison with normal subjects in all patients. The Turner index [(serum insulin x 100)/(blood sugar--30]) was lower than normal at all points of the GTT, suggesting a decreased insulin secretion in relation to serum glucose level. Blood glucose level at 120 min was correlated to age, serum bilirubin and prothrombin time. Thus, chronic liver damage is a risk factor for diabetes mellitus. The alteration of carbohydrate metabolism is correlated to the severity of liver disfunction. The initial pathogenic factor may be hyperinsulinism and resistance to insulin, followed by decreased secretion of the hormone.

[The effect of anti-insulin antibodies and of peptide C residual secretion on the metabolic control of diabetes type 1]

In 20 type I diabetic patients treated with conventional insulin preparations, we measured insulin antibodies and peptide C secretion. Peptide C levels 90 and 120 min after a standard breakfast correlated well with glucosylated Hb levels (r = -0.48 and -0.52, respectively). No correlation with free insulin levels was observed, in spite of a good correlation of the latter with blood glucose levels (r = -0.50 and -0.73, respectively). There was no relation between insulin antibody levels and peptide C or free insulin. Metabolic control was not affected by insulin antibodies. Insulin dose decreased in relation to the duration of the disease and reduction of body weight index and was not correlated to glycosylated Hb levels.

[Serum lipids, HDL2 and HDL3 cholesterol and apolipoproteins A1 and B as predictors of coronary artery disease diagnosed by coronarography]

Serum levels of total, HDL2 and HDL3 cholesterol, triglycerides and apolipoproteins A1 and B were compared in 100 Chilean males with (n = 80) or without (n = 20) coronary artery disease (CAD). The presence and severity of CAD was determined by an angiographic score. Discriminating power, sensitivity, specificity and positive predictive value for CAD were calculated for all variables. As an isolated factor, total cholesterol had the greatest discriminating power (p less than 0.002): 21% of patients with CAD had cholesterol levels below 200 mg/dl while no patient with cholesterol over 275 mg/dl was free of disease. Even though all cases with HDL cholesterol below 25 mg/dl belonged in the CAD group, this factor had no overall discriminating power. Total cholesterol/HDL cholesterol ratio had the greatest discriminating power (p less than 0.001) while total/HDL2 cholesterol had the best positive predictive value.

[Metabolic control of non insulin dependent diabetes mellitus in surgery]

We followed 50 type II diabetic patients undergoing various types of surgical procedures. Control of blood sugar was evaluated as percent of tests within an acceptable limit defined as 160 mg/dl in the preoperative period, 80-240 mg/dl in the early postoperative period and 80-120 mg/dl thereafter. Adequate control was present in 56% of tests in the first period, 95% in the second and 70% in the third. Only 2 subjects experienced hypoglycemia with no sequelae. No cases of ketoacidosis or hyperosmolar coma were observed. Overall mortality was 2% and complications included electrolyte alterations in 8%, acid base disturbance in 4% and infection in 16%. Thus, adequate metabolic control and low morbidity and mortality are possible in patients with type II diabetes undergoing surgery.

Complications and outcome of pregnancy in obese women

To examine the influence of obesity on obstetric performance, pregnancy outcome, and lactational performance, 163 mostly moderately obese gravidas were compared with age and parity-matched normal weight subjects. Significantly increased incidences of gestational hypertension, inadequate pregnancy weight gain, cesarean section, postpartum infections, and large-for-gestational age infants were observed in the study group. No significant increase in the incidence of diabetes, toxemia, breech presentation, postpartum hemorrhage, infant morbidity or lactational failure was noted in obese women. The mean birth weight of the infants of obese women was 163g greater than that of the control subjects; no difference was observed in infant length or gestational age. These results, while confirming that obesity is an important risk factor, suggest that methodological aspects of the previous studies may have contributed to magnify the severity of the problem.

[Formulation, preparation and evaluation of shortening, laminated and cut biscuits, for diabetic patients]

Laminated and cut cookies formulated with natural and/or artificial sweeteners as substitutes of sucrose, are presented as a new alternative of choice for persons on a restricted diet. According to data in the literature, market availability and technological and economic limitations involved in the use of pure sweeteners, four mixtures were selected for the formulation of the cookies, instead of sucrose. Their composition and relative sweetness were as follows: (table; see text) After the statistical analysis of results, formulations presenting significantly superior quality characteristics were selected. As observed, all alternatives subjected to evaluation were grade 1. A study of acceptability by diabetic patients was carried out with these products through a ranking test, in order to determine which were the formulations preferred. This revealed a significant preference for the cookies containing saccharin-sorbitol = 0.35:99.65, at a 1% level of significance. Their nutritional and caloric values, as well as the chemical composition of the selected formulations were then determined. The results showed a 10.9% decrease in caloric contribution.

Cholesterol distribution among lipoprotein fractions in patients with gout and normal controls

The relationship between gout and coronary disease is controversial. We studied the distribution of cholesterol among lipoprotein fractions separated by ultracentrifugation in a group of 29 gouty men and 34 healthy controls, matched by age, weight and serum glucose. Our results showed that patients had significantly higher serum triglycerides and cholesterol-VLDL and lower total cholesterol and cholesterol in LDL and HDL fractions. The comparison of both groups separated by weight and alcohol intake showed similar results. The cholesterol-LDL/cholesterol-HDL ratio was not significantly different between the groups. Based on these results, we conclude that our group of gouty patients may not be at greater risk of coronary disease than a similar control population.