Tomoko Inoue

Surrogate markers of insulin resistance in assessing individuals with new categories “prehypertension” and “prediabetes”

Abstract Background: There are few data on the impact of insulin resistance on the recently defined categories of prehypertension (PHT) and prediabetes (PDM). The aim of this study was to examine associations of surrogate markers of insulin resistance with PHT/PDM. Methods: Subjects included 554 individuals who underwent a 75-g oral glucose tolerance test (OGTT). They were classified into four groups using a severity score for high blood pressure and glucose tolerance. Insulin resistance was measured using the homeostasis model assessment of insulin resistance (HOMA-R) and three surrogate markers obtained from 75-g OGTT values (ISI-composite, Stumvoll index, and OGIS index). Results: HOMA-R increased significantly, but the other three surrogate indices decreased with increasing severity score. Of these markers, the OGIS index was mostly associated with prevalent PHT/PDM and the odds ratio for insulin resistance was 3.61 (95% CI 1.68–7.76, p=0.001) for subjects with either PHT or PDM and 29.98 (12.81–70.18, p<0.001) for subjects with both PHT and PDM. Conclusions: PHT and PDM frequently coexist in relatively lean Japanese subjects. Decreased insulin sensitivity may contribute to the underlying status of PHT/PDM. Among the surrogate markers of insulin resistance, the OGIS index is the most sensitive for assessment of PHT/PDM status. Clin Chem Lab Med 2007;45:35–9.

Eicosapentaenoic Acid (EPA) Decreases the All-Cause Mortality in Hemodialysis Patients

OBJECTIVE Atherosclerosis, which causes cardiovascular disease, is a major cause of death in hemodialysis (HD) patients. Eicosapentaenoic acid (EPA), an anti-hyperlipidemic agent, is known to have antioxidative or anti-inflammatory effects, resulting in improvements in atherosclerosis. In the present study, we examined whether EPA improves the all-cause mortality in patients receiving regular HD therapy. METHODS We enrolled 176 patients treated with maintenance HD therapy and performed a longitudinal observational cohort study for three years. We divided the patients into two groups based on whether or not the received EPA treatment [EPA(+) and EPA(-), respectively]. The primary end-point was all-cause death. We also matched the two groups using propensity score matching and examined the effect of EPA. RESULTS Before matching, the all-cause mortality rates were 24.0% in the EPA(+) and 11.8% in the EPA(-) groups, which were significantly different (p=0.044). After propensity score matching, the EPA(+) group still showed a significantly better prognosis than the EPA(-) group (p=0.038). A multivariate analysis showed that EPA treatment significantly reduced the risk of all-cause mortality both before and after propensity score matching. CONCLUSION EPA treatment is independently associated with lower mortality in HD patients.