Itahisa Marcelino Rodríguez

C-peptide as a risk factor of coronary artery disease in the general population:

OBJECTIVE To analyse the association between serum C-peptide and coronary artery disease in the general population. METHODS Follow-up study of 6630 adults from the general population. They were stratified into group 1 (no insulin resistance: C-peptide < third tercile and glycaemia < 100 mg/dL), group 2 (initial insulin resistance: C-peptide ⩾ third tercile and glycaemia < 100 mg/dL) and group 3 (advanced insulin resistance: glycaemia ⩾ 100 mg/dL). RESULTS After 3.5 years of follow-up, group 2 had a higher incidence of myocardial infarction (relative risk (RR) = 4.2, 95% confidence interval (CI) = 1.7-10.6) and coronary artery disease (RR = 3.5, 95% CI = 1.9-6.6) than group 1. Group 3 also had increased incidences of both diseases. In multivariable analysis of the entire population, groups 2 and 3 showed significant risks of myocardial infarction and coronary artery disease (RR > 3 and RR > 2, respectively). However, when people with diabetes were excluded, the increased risks were corroborated only in group 2 for myocardial infarction (RR = 2.8, 95% CI = 1.1-6.9; p = 0.025) and coronary artery disease (RR = 2.4, 95% CI = 1.3-4.6; p = 0.007). CONCLUSION Elevated C-peptide is associated with the incidence of myocardial infarction and coronary artery disease in the general population. It can be an earlier predictor of coronary events than impaired fasting glucose.Objective: To analyse the association between serum C-peptide and coronary artery disease in the general population. Methods: Follow-up study of 6630 adults from the general population. They were stratified into group 1 (no insulin resistance: C-peptide 3 and RR > 2, respectively). However, when people with diabetes were excluded, the increased risks were corroborated only in group 2 for myocardial infarction (RR = 2.8, 95% CI = 1.1–6.9; p = 0.025) and coronary artery disease (RR = 2.4, 95% CI = 1.3–4.6; p = 0.007). Conclusion: Elevated C-peptide is associated with the incidence of myocardial infarction and coronary artery disease in the general population. It can be an earlier predictor of coronary events than impaired fasting glucose.

Incidence, Mortality and Positive Predictive Value of Type 1 Cardiorenal Syndrome in Acute Coronary Syndrome.

Objectives To determine whether the risk of cardiovascular mortality associated with cardiorenal syndrome subtype 1 (CRS1) in patients who were hospitalized for acute coronary syndrome (ACS) was greater than the expected risk based on the sum of its components, to estimate the predictive value of CRS1, and to determine whether the severity of CRS1 worsens the prognosis. Methods Follow-up study of 1912 incident cases of ACS for 1 year after discharge. Cox regression models were estimated with time to event (in-hospital death, and readmission or death during the first year after discharge) as the dependent variable. Results The incidence of CRS1 was 9.2/1000 person-days of hospitalization (95% CI = 8.1–10.5), but these patients accounted for 56.6% (95% CI = 47.4–65.) of all mortality. The positive predictive value of CRS1 was 29.6% (95% CI = 23.9–36.0) for in-hospital death, and 51.4% (95% CI = 44.8–58.0) for readmission or death after discharge. The risk of in-hospital death from CRS1 (RR = 18.3; 95% CI = 6.3–53.2) was greater than the sum of risks associated with either acute heart failure (RR = 7.6; 95% CI = 1.8–31.8) or acute kidney injury (RR = 2.8; 95% CI = 0.9–8.8). The risk of events associated with CRS1 also increased with syndrome severity, reaching a RR of 10.6 (95% CI = 6.2–18.1) for in-hospital death at the highest severity level. Conclusions The effect of CRS1 on in-hospital mortality is greater than the sum of the effects associated with each of its components, and it increases with the severity of the syndrome. CRS1 accounted for more than half of all mortality, and its positive predictive value approached 30% in-hospital and 50% after discharge.

Anti-dsDNA antibodies in systemic lupus erythematosus: A combination of two quantitative methods and the ANA pattern is the most efficient strategy of detection.

Several methods have been used to measure anti-double-stranded DNA auto-antibody (anti-dsDNA). Our aim was to determine the most efficient strategy to test anti-dsDNA in systemic lupus erythematosus (SLE). In this study, anti-dsDNA and anti-nuclear antibody (ANA) tests were requested for 644 patients. Anti-dsDNA was tested by RIA, ELISA and CLIA in all patients. The results indicated that 78 patients had a positive anti-dsDNA test according to at least one of the methods. After a 3-year follow-up period only 26 patients were diagnosed with SLE. We evaluated each method and combination of methods. Specificity and positive predictive value (PPV) increased with the number of assay methods used (p=0.002 for trend), and PPV was 100% in patients whose results were positive by all three anti-dsDNA assay methods. The proportion of anti-dsDNA-positive patients who had SLE was highest (82%; p b 0.001) among those with a homogeneous pattern of ANA staining, followed by those with a speckled pattern. In ANA positive patients, when only RIA was considered, 59% of anti-dsDNA-positive patients had SLE, but when RIA and CLIA were both considered, all patients with positive results on both tests had SLE. The combination of RIA+CLIA in patients with homogeneous and speckled ANA staining showed a similar cost and higher sensitivity than RIA alone in ANA positive patients (p b 0.001). We conclude that the most efficient strategy was to combine simultaneously two quantitative and sensitive methods but only in patients with a homogeneous or speckled pattern of ANA staining. This approach maximized specificity and PPV, and reduced costs.

Strategies to improve the efficiency of celiac disease diagnosis in the laboratory

The demand for testing to detect celiac disease (CD) autoantibodies has increased, together with the cost per case diagnosed, resulting in the adoption of measures to restrict laboratory testing. We designed this study to determine whether opportunistic screening to detect CD-associated autoantibodies had advantages compared to efforts to restrict testing, and to identify the most cost-effective diagnostic strategy. We compared a group of 1678 patients in which autoantibody testing was restricted to cases in which the test referral was considered appropriate (G1) to a group of 2140 patients in which test referrals were not reviewed or restricted (G2). Two algorithms A (quantifying IgA and Tissue transglutaminase IgA [TG-IgA] in all patients), and B (quantifying only TG-IgA in all patients) were used in each group, and the cost-effectiveness of each strategy was calculated. TG-IgA autoantibodies were positive in 62 G1 patients and 69 G2 patients. Among those positive for tissue transglutaminase IgA and endomysial IgA autoantibodies, the proportion of patients with de novo autoantibodies was lower (p=0.028) in G1 (11/62) than in G2 (24/69). Algorithm B required fewer determinations than algorithm A in both G1 (2310 vs 3493; p<0.001) and G2 (2196 vs 4435; p<0.001). With algorithm B the proportion of patients in whom IgA was tested was lower (p<0.001) in G2 (29/2140) than in G1 (617/1678). The lowest cost per case diagnosed (4.63 euros/patient) was found with algorithm B in G2. We conclude that opportunistic screening has advantages compared to efforts in the laboratory to restrict CD diagnostic testing. The most cost-effective strategy was based on the use of an appropriate algorithm.

Hospital Mortality in 415 798 AMI Patients: 4 Years Earlier in the Canary Islands Than in the Rest of Spain

INTRODUCTION AND OBJECTIVES The Canary Islands has the highest mortality from diabetes in Spain. The aim of this study was to determine possible differences in mortality due to acute myocardial infarction (AMI) during hospital admission between this autonomous community and the rest of Spain, as well as the factors associated with this mortality and the population fraction attributable to diabetes. METHODS Cross-sectional study of hospital admissions for AMI in Spain from 2007 to 2014, registered in the Minimum Basic Data Set. RESULTS A total of 415 798 AMI were identified. Canary Island patients (16 317) were younger than those living in the rest of Spain (63.93 ± 13.56 vs 68.25 ± 13.94; P < .001) and death occurred 4 years earlier in the archipelago (74.03 ± 11.85 vs 78.38 ± 11.10; P < .001). This autonomous community had the highest prevalence of smoking (44% in men and 23% in women); throughout Spain, AMI occurred 13 years earlier in smokers than in nonsmokers. Patients in the Canary Islands had the highest mortality rates whether they had diabetes (8.7%) or not (7.6%), and they also showed the highest fraction of AMI mortality attributable to diabetes (9.4; 95%CI, 4.8-13.6). After adjustment for type of AMI, diabetes, dyslipidemia, hypertension, smoking, cocaine use, renal failure, sex and age, the Canary Islands showed the highest risk of mortality vs the rest of Spain (OR = 1.25; 95%CI, 1.17-1.33; P < .001) and it was one of the autonomous communities showing no significant improvement in the risk of mortality due to AMI during the study period. CONCLUSIONS Mortality due to AMI during hospital admission is higher in the Canary Islands than in the rest of Spain.