Hyperferritinemia Is a Predictor of Onset of Diabetes in Japanese Males Independently of Decreased Renal Function and Fatty Liver: A Fifteen-Year Follow-Up Study

Risk factors for chronic kidney disease progression over 20 years for primary prevention in Japanese individuals at a preventive medicine research center: Focus on the influence of plasma glucose levels

AIMS/INTRODUCTION

Chronic kidney disease (CKD) is a very important issue globally because of the risk of its progressing to end-stage renal disease. We aimed to identify factors contributing to long-term estimated glomerular filtration rate (eGFR) decline to determine an early diagnosis and prevent CKD progression.

MATERIALS AND METHODS

From January 2003 to December 2006, 5,507 individuals underwent health checkups at our hospital's Preventive Medicine Research Center. We ultimately enrolled 2,175 individuals. The eGFR was ≥60 mL/min/1.73 m2 at the start of observation period, which was 20 years. The event onset time was the day that the eGFR became <30 mL/min during the 20-year period. Baseline risk factors - in particular, the effect of plasma glucose levels on the eGFR - were extracted and evaluated by using Fine and Gray analysis.

RESULTS

During the 20-year observation, the hazard ratio (HR) of CKD progression was examined. A fasting plasma glucose (FPG) level ≥105 mg/dL was significantly associated with the risk of CKD progressing to an eGFR <30 mL/min. This trend was similar in the slope of eGFR. An FPG ≥105 mg/dL or an glycated hemoglobin level ≥6.5% was useful for intervening in CKD progression. Multivariate analysis showed that independent risk factors were an FPG level ≥105 mg/dL (HR 1.9; P < 0.001), age ≥60 years (HR 3.86; P < 0.001), obesity (HR 1.61; P < 0.01) and urinary protein (HR 1.55; P < 0.01).

CONCLUSIONS

For early intervention against a reduction in the eGFR, detecting mild increases in FPG ≥105 mg/dL in patients with CKD with or without diabetes is useful.

Sex differences in predictive factors for onset of type 2 diabetes in Japanese individuals: A 15-year follow-up study

AIMS/INTRODUCTION

The increase in the number of patients with type 2 diabetes mellitus is an important concern worldwide. The goal of this study was to investigate factors involved in the onset of type 2 diabetes mellitus, and sex differences in long-term follow up of people with normal glucose tolerance.

MATERIALS AND METHODS

Of 1,309 individuals who underwent screening at our facility in 2004, 748 individuals without diabetes were enrolled. Correlations of metabolic markers including serum adiponectin (APN) with onset of type 2 diabetes mellitus were examined over 15 years in these individuals.

RESULTS

The Kaplan-Meier curve for onset of type 2 diabetes mellitus for 15 years in the decreased APN group was examined. Hazard ratios for the APN concentration for onset of diabetes were 1.78 (95% confidence interval [CI] 1.20-2.63, P = 0.004) in all participants, 1.48 (95% CI 0.96-2.29, P = 0.078) for men and 3.01 (95% CI 1.37-6.59, P = 0.006) for women. During the follow-up period of 15 years, body mass index, estimated glomerular filtration rate, fatty liver, C-reactive protein and alanine aminotransferase in men were significant in univariate analysis, but only estimated glomerular filtration rate and fatty liver were significantly related to onset of type 2 diabetes mellitus in multivariate analysis. In women, body mass index, systolic blood pressure, triglyceride, fatty liver and APN were significant in univariate analysis, and APN was the only significant risk factor in multivariate analysis (P < 0.05).

CONCLUSIONS

There are differences between men and women with regard to targets for intervention to prevent the onset of type 2 diabetes mellitus. Individuals requiring intensive intervention should be selected with this finding to maximize the use of limited social and economic resources.