Resistin as a risk factor for all-cause (and cardiovascular) death in the general population.

Serum resistin is a pro-inflammatory cytokine that has been described as a risk factor associated with mortality in several clinical sets including type 2 diabetes. Mortality studies in the general population are needed to find out the risk of death associated to this cytokine. In a follow-up study of a cohort of adult population (n = 6636) in Spain over a period of fifteen years (447 deaths/102,255 person-years), serum resistin measurements and death records were obtained. The risks of all-cause deaths, and deaths from cardiovascular and oncological diseases were estimated. Hazard ratios (HR) and its confidence intervals (CI) were calculated using multivariable Cox models, adjusting the effect of 11 traditional risk factors. The risk of all-cause mortality among participants exposed to the highest quintile of resistin was always higher than among those in the lowest quintile (HR varied between 1.55 when smoking was the adjusted factor [95% CI 1.17-2.05], and 1.68 when the adjusted factor was physical activity [95% CI 1.27-2.21]). The maximally adjusted model, accounting for the effect of all traditional factors, corroborated this higher risk of all-cause mortality among people in the highest resistin quintile (HR = 1.52; 95% CI 1.13-2.05). The effect of resistin was even higher for cardiovascular deaths (HR = 2.14; 95% CI 1.13-4.06), being exceeded only by suffering diabetes (HR = 3.04; 95% CI 1.98-4.69) or previous acute coronary syndrome (HR = 3.67; 95% CI 2.18-6.18). This findings corroborate the role of resistin as a risk factor for all-cause (and cardiovascular) death in the general population.

[Lifestyle and treatment adherence of type 2 diabetes mellitus people in the Canary Islands]. / Estilo de vida y adherencia al tratamiento de la población canaria con diabetes mellitus tipo 2.

BACKGROUND: The Canary Islands population experiences the highest type 2 diabetes (DM2) mortality in Spain. We studied lifestyle, unknown DM2 and treatment adherence in diabetics of these islands. METHODS: Cross-sectional study of 6729 subjects from the general population (age 18-75) that participate in the cohort study "CDC of the Canary Islands". We found out their medical problems, diet, physical activity, medications, smoking, etc. RESULTS: Prevalence of DM2 was 12% in men and 10% in women (p=0.005). The disease was unknown in 22% of men and 9% of women (p < 0.001). Considering unknown DM2, lack of treatment and lack of adherence, 48% of men and 28% of women did not follow a regular treatment. Diabetics' men prevalences of smoking (28%; CI(95%)=23-33) and sedentariness (62%; CI(95%)=56-68) were similar to non diabetic men, but obesity was more frequent in diabetics (45 versus 25%; p < 0.001). Diabetics women showed a higher obesity (54 versus 27%; p < 0.001) and a lower smoking prevalence (11 versus 22%; p < 0,001) than non diabetics, but they presented a similar sedentariness (75%; CI(95%)=70-79). In both sexes, energy intake was lower in diabetics (p < 0.001), but 93% of them (CI(95%)=91-95) showed a high consumption of calories from saturated fat and 69% (CI(95%)=65-72) presented metabolic syndrome. CONCLUSIONS: The Canarian diabetics are a sedentary and obese population that show a high consumption of saturated fats and high prevalence of metabolic syndrome. The proportion of them following regular treatment is low, specially in diabetic men that, in addition, still smoke.

Hemodynamics and metabolism at low versus moderate altitudes.

Despite the higher prevalence of diabetes and hypertension in populations residing at moderate altitudes, mortality in these populations is lower than in populations residing at low altitudes. To examine whether metabolic and hemodynamic differences can explain this apparent paradox, we performed a cross-sectional study of a general population sample recruited in the Canary Islands, Spain (n=6729). We recorded altitude of residence, age, heart rate, blood pressure, body mass index, social class, physical activity, energy intake, alcohol intake, smoking habit, prevalence of type 2 diabetes mellitus and hypertension. In a subsample (n=903), we recorded serum concentration of cholesterol, triglycerides, glucose, C peptide, leptin, soluble leptin receptor (sObR), C-reactive protein, resistin, soluble CD40 ligand (sCD40L), and paraoxonase activity (PON), and we estimated insulin resistance and free leptin index. We found an inverse association between altitude and heart rate (p<0.001), leptin (p<0.001), free leptin index (p<0.001), resistin (p<0.001), and sCD40L (p<0.05) and a direct association between altitude and hypertension (odds ratio=1.29 for altitude >600 m; 95% confidence interval=1.03-1.62), glycemia (p<0.05), C peptide (p<0.001), insulin resistance (p<0.001), sObR (p<0.05), and PON (p<0.05). When social class was included in the multivariate model, the association with PON was no longer significant. In conclusion, individuals residing at moderate altitudes have a lower heart rate and lower serum concentration of total leptin, free leptin, and sCD40L. These differences may partially explain the lower mortality in these populations.

A simple clinical score for type 2 diabetes mellitus screening in the Canary Islands.

AIM: To develop a straightforward risk score for type 2 diabetes (DM2) screening to use in clinical practice. METHODS: A sample of 6237 adult inhabitants of the Canary Islands (Spain) was randomly divided into two subgroups: one yielded data used to develop the instrument, and the other yielded data used for validation testing. Performance of the instrument was compared in persons with clinically diagnosed DM2 and undiagnosed diabetes. The risk score, calculated by multivariate logistic regression, included the potential risk variables that yielded the highest odds ratio in the univariate analysis. A cut-off point for screening purposes was established at a 99% negative predictive value. RESULTS: In men, variables included in the risk score were age, waist/height ratio, familial antecedents of diabetes, and systolic blood pressure (ROC curve 0.837, 95% CI: 0.803-0.871). In women, the risk score contained the same variables plus gestational diabetes history (ROC curve 0.874, 95% CI: 0.847-0901). Excluding systolic blood pressure from the score had no significant effect on the area under the curve. This instrument resulted valid only for people aged less than 55 years. CONCLUSIONS: This simple risk score for DM2 would be easy to apply in clinical practice.

Leptin and altitude in the cardiovascular diseases.

OBJECTIVE: The lower mortality from coronary ischemic disease in populations living at high altitude has been related to an increase of high-density lipoprotein (HDL)-cholesterol at altitude. Leptin has been proposed as a cardiovascular risk factor. We investigated whether leptin varies according to the altitude at which people live. RESEARCH METHODS AND PROCEDURES: This was a cross-sectional study of the first 889 people enrolled in a cohort study in the Canary Islands, Spain. The relationship among serum leptin, altitude, obesity, and other cardiovascular risk factors was analyzed by bivariate and multivariate tests. RESULTS: Leptin levels showed an inverse correlation to altitude expressed in meters (r = -0.10). Obese subjects had this leptin-altitude association (r = -0.19), but they also had a direct correlation of leptin to HDL-cholesterol (r = 0.27) and an inverse correlation of leptin to the total cholesterol-to-HDL-cholesterol ratio (r = -0.34), triglycerides (r = -0.29), apolipoprotein B (r = -0.21), and glycemia (r = -0.19). Nonobese subjects had only the leptin-altitude association (r = -0.11). The final regression model included altitude as predictor. Other associated variables were gender, physical activity, BMI, age, smoking (reducing leptin independently of BMI), alcohol, heart rate, and income. DISCUSSION: Serum leptin level decreases when altitude increases, and this association could help to explain the lower cardiovascular mortality rate at high altitude. However, because in obese subjects there is a direct association of leptin with HDL-cholesterol and an inverse association with the lipid atherogenic fractions, we suggest the hypothesis of different roles for bound and free leptin, with free leptin being a cardiovascular protective factor in obese people.