Impacts of chronic kidney disease and diabetes on cardiovascular mortality in a general Japanese population: A 20-year follow-up of the NIPPON DATA90 study

Urinary Na/K ratio is a predictor of developing chronic kidney disease in the general population

Chronic kidney disease (CKD) is a major risk factor for cardiovascular diseases as well as end-stage kidney disease. Increased dietary sodium (Na) or decreased dietary potassium (K) deteriorates kidney function; however, findings regarding the association of dietary Na/K ratio with kidney function are limited and conflicting. Therefore, the present study investigated the impact of urinary Na/K ratio on the development of CKD, defined as estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2, in the Japanese general population. In total, 14,549 subjects without CKD who participated in our medical checkup were enrolled. The urinary Na/K ratio was measured using a sample of overnight urine. The subjects were followed up until the endpoint (onset of CKD). During the median follow-up period of 61.4 months, CKD developed in 2096 participants (25.9 per 1000 person-years). The risk of developing CKD increased across the quartiles of baseline urinary Na/K ratio in the Kaplan-Meier analysis (log-rank, P < 0.001). In multivariate Cox proportional hazard regression analysis, urinary Na/K ratio was a significant predictor of new-onset CKD after adjustment for important factors including eGFR at baseline (hazard ratio, 2.013; 95% confidence interval, 1.658-2.445; p < 0.001). Moreover, baseline urinary Na/K ratio was found to be independently correlated with yearly decline in eGFR. Similar results were obtained in subgroups of participants with and without hypertension. Thus, urinary Na/K ratio is significantly associated with the development of CKD in the general population.

Effect of Chronic Kidney Disease or Anemia or Both on Cardiovascular Mortality in a 25-Year Follow-Up Study of Japanese General Population (From NIPPON DATA90)

The relation between chronic kidney disease (CKD) and cardiovascular disease (CVD) in the general population is well elucidated. In patients with CKD, anemia is associated with adverse outcomes. However, the effects of CKD and anemia on CVD in the general population remains poorly explored, especially in Asian populations. This study aimed to investigate the effect of CKD and/or anemia on CVD mortality in a long-term cohort study involving Japanese community dwellers. We assessed 7,339 participants (aged ≥30 years) with no CVD history. These participants were divided into 4 categories according to their CKD (estimated glomerular filtration rate <60 or urine protein >1+ by dipstick qualitative test) and/or anemia (hemoglobin: <13 g/100 ml [men], <12 g/100 ml [women]) statuses. For each category, we calculated the hazard ratios (HRs) of CVD mortality by using the Cox proportional hazards model after adjusting for age, body mass index, hypertension, diabetes, dyslipidemia, smoking, and alcohol drinking. Within 25 years of follow-up, 637 participants died because of CVD. The HRs of CVD in patients with CKD only, anemia only, and both were 1.27, 1.59, and 2.60 (95% confidence intervals [CI] 1.06 to 1.53, 1.34 to 1.90, and 1.80 to 3.76) in men and 1.42, 1.08, and 2.00 (95% CI 1.19 to 1.69, 0.99 to 1.18, and 1.54 to 2.60) in women, respectively. In conclusion, CKD with anemia is associated with an increased risk for CVD mortality in a general population in Japan.

Relationship between non-fasting triglycerides and cardiovascular disease mortality in a 20-year follow-up study of a Japanese general population: NIPPON DATA90

Background

Non-fasting triglycerides (TG) are considered a better predictor of cardiovascular disease (CVD) than fasting TG. However, the effect of non-fasting TG on fatal CVD events remains unclear. In the present study, we aimed to explore the relationship between non-fasting TG and CVD mortality in a Japanese general population.

Methods

A total of 6,831 participants without a history of CVD, in which those who had a blood sampling over 8 hours or more after a meal were excluded, were followed for 18.0 years. We divided participants into seven groups according to non-fasting TG levels: ≤59 mg/dL, 60–89 mg/dL, 90–119 mg/dL, 120–149 mg/dL, 150–179 mg/dL, 180–209 mg/dL, and ≥210 mg/dL, and estimated the multivariable-adjusted hazard ratios (HRs) of each TG group for CVD mortality after adjusting for potential confounders, including high density lipoprotein cholesterol. Additionally, we performed analysis stratified by age <65 and ≥65 years.

Results

During the follow-up period, 433 deaths due to CVD were detected. Compared with a non-fasting TG of 150–179 mg/dL, non-fasting TG ≥210 mg/dL was significantly associated with increased risk for CVD mortality (HR 1.56: 95% CI, 1.01–2.41). Additionally, lower levels of non-fasting TG were also significantly associated with increased risk for fatal CVD. In participants aged ≥65 years, lower levels of non-fasting TG had a stronger impact on increased risk for CVD mortality, while higher levels of non-fasting TG had a stronger impact in those aged <65 years.

Conclusion

In a general Japanese population, we observed a U-shaped association between non-fasting TG and fatal CVD events.

Estimated 24 h Urinary Sodium-to-Potassium Ratio Is Related to Renal Function Decline: A 6-Year Cohort Study of Japanese Urban Residents

The effect of the sodium-to-potassium ratio (Na/K) on renal function within the clinically normal range of renal function are limited. We investigated the effects of an estimated 24 h urinary Na/K (e24hUNa/K) on a 6-year renal function decline among 927 urban Japanese community dwellers with no history of cardiovascular diseases and medication for hypertension, diabetes, or dyslipidemia. We partitioned the subjects into quartiles according to the e24hUNa/K. The estimated glomerular filtration rate (eGFR) was calculated using the chronic kidney disease epidemiology collaboration (CKD/EPI) formula and renal function decline was defined as an absolute value at or above the third quartile of the eGFR decline rate. A multivariable logistic regression model was used for estimation. Compared with the first quartile of the e24hUNa/K, multivariable-adjusted odds ratios (ORs) for eGFR decline in the second, third, and fourth quartiles were 0.96 (95% confidence interval: 0.61–1.51), 1.06 (0.67–1.66), and 1.65 (1.06–2.57), respectively. These results were similar when the simple spot urine Na/K ratio was used in place of the e24hUNa/K. Apparently healthy urban residents with an almost within normal range mean baseline eGFR and high e24hUNa/K ratios had an increased risk for a future decline in renal function. Reducing the Na/K ratio may be important in the prevention of chronic kidney disease in its early stage.

Efficacy and safety of trelagliptin in Japanese patients with type 2 diabetes with severe renal impairment or end-stage renal disease: Results from a randomized, phase 3 study

INTRODUCTION

To investigate the efficacy and safety of trelagliptin 25 mg in patients with type 2 diabetes mellitus with severe renal impairment or end-stage renal disease.

MATERIALS AND METHODS

This multicenter, randomized, phase 3 study comprised a 12-week double-blind phase followed by a 40-week open-label phase. Patients had type 2 diabetes mellitus with severe renal impairment (creatinine clearance <30 mL/min) or end-stage renal disease (undergoing hemodialysis), and were receiving diet and/or exercise therapy with/without one antidiabetic drug.

RESULTS

Patients were randomized to trelagliptin (A/A, n = 55) or placebo (P/A, n = 52; double-blind phase). Both groups received trelagliptin in the open-label phase. The least square mean change (95% confidence interval [CI]) from baseline in hemoglobin A1c at the end of the double-blind phase was -0.71% (95% CI -0.885, -0.542) and 0.01% (95% CI -0.170, 0.183) in the A/A and P/A groups, respectively (intergroup least square means difference -0.72%, 95% CI -0.966, -0.473; P < 0.0001). Mean hemoglobin A1c decreased after trelagliptin treatment in the P/A group to similar levels observed in the A/A group and remained comparable in both groups versus baseline up to week 52. In the double-blind phase, the incidence of treatment-emergent adverse events (TEAEs) was 72.7% and 61.5% in the A/A and P/A group, respectively; most TEAEs were mild-to-moderate, except in one patient (P/A group), who experienced two severe TEAEs. The incidence of serious TEAEs was 7.3% and 3.8% in the A/A and P/A group, respectively.

CONCLUSIONS

Once-weekly trelagliptin 25 mg was efficacious, with no major safety concerns, and represents a meaningful treatment option in this patient population.

Inflammation as a predictor of acute kidney injury and mediator of higher mortality after acute kidney injury in non-cardiac surgery

This retrospective cohort study examined the roles of inflammation in acute kidney injury (AKI). Serum albumin and C-reactive protein (CRP) were used as markers of inflammation. Adults who underwent non–cardiac surgery from 2007 to 2011 were included. Exclusion criteria were urological surgery, obstetric surgery, missing data, and pre-operative dialysis. Subjects were followed until the end of 2015 or loss to follow-up. Associations between pre–operative albumin or CRP and post-operative AKI or association between AKI and mortality were examined by logistic or Cox regression, respectively. Mediation analyses were performed using albumin and CRP as mediators. Among 4,538 subjects, 272 developed AKI. Pre-operative albumin was independently associated with AKI (odds ratio [95% confidence interval (CI)]: 0.63 [0.48–0.83]). During a median follow-up of 4.5 years, 649 died. AKI was significantly associated with mortality (hazard ratio [HR] [95% CI]: 1.58 [1.22–2.04]). Further adjustment for pre-operative albumin and CRP attenuated the association (HR [95% CI]: 1.28 [0.99–1.67]). The proportions explained by mediating effects of lnCRP and albumin were 29.3% and 39.2% and mediation effects were statistically significant. In conclusion, inflammation is a predictor of AKI and a mediator of mortality after AKI. Interventions targeting inflammation might improve outcomes of AKI.

Sex-specific clinical outcomes of impaired glucose status: A long follow-up from the Tehran Lipid and Glucose Study

AIMS

To investigate the sex-specific associations of prediabetes with major clinical outcomes including incident type 2 diabetes, chronic kidney disease, hypertension, coronary heart disease, stroke and all-cause mortality.

METHODS

Among 8498 Iranian adults from the Tehran Lipid and Glucose Study, aged ≥30 years and without diagnosed type 2 diabetes, gender-interactions were assessed for each outcome, followed by sex-separated multivariate-adjusted Cox proportional hazard models to calculate hazard ratios and 95% confidence intervals (CIs) of different prediabetes categories, including impaired fasting glucose (IFG), defined by the American Diabetes Association (ADA) and World Health Organization (WHO), as fasting plasma glucose of 5.6-6.9 mmol/L and 6.1-6.9 mmol/L, respectively, and impaired glucose tolerance, defined as 2-h post challenge plasma glucose of 7.8-11 mmol/L.

RESULTS

Sex-specific associations existed for men between IFG-ADA and chronic kidney disease (hazard ratio: 1.28, 95% CI 0.99-1.65; p_interaction = 0.008) and between IFG-WHO and stroke (hazard ratio: 2.15, 95% CI 1.08-4.27; p_interaction = 0.21); and for women between IFG-ADA and hypertension (hazard ratio: 1.24, 95% CI 1.04-1.48; p_interaction = 0.06) and between impaired glucose tolerance and coronary heart disease (hazard ratio: 1.57, 95% CI 1.14-2.16; p_interaction = 0.05). Among both genders, all prediabetes definitions were associated with type 2 diabetes but none with mortality.

CONCLUSIONS

The hazards of prediabetes definitions may differ between genders depending on the outcome of interest. IFG-WHO among men and impaired glucose tolerance among women are particularly important because of their association with incident stroke and coronary heart disease, respectively. Considering these sex differences could improve personalized management of prediabetes.

Overweight or underweight and the risk of decline in activities of daily living in a 22-year cohort study of a Japanese sample

AIM

The present study aimed to clarify the association between body mass index (BMI) and the activities of daily living (ADL). Although BMI is likely to be concerned regarding the relationship with specific diseases or mortality, few studies have focused on the relationship of BMI and ADL.

METHODS

A total of 3353 Japanese participants of a 22-year cohort study from 1990 to 2012 aged 45-74 years at baseline were divided into four groups according to their BMI levels: ≤18.5, 18.5-21.9 (reference), 22.0-24.9 and ≥25.0 kg/m² . Outcomes were becoming dependent in ADL (including death after ADL decline) and death without observation of ADL decline as a competing risk. Sex-specific multinomial logistic regression analysis was carried out in 2017 to estimate the odds ratios (OR) after adjusting for age, smoking, alcohol drinking, hypertension, hypercholesterolemia, diabetes and serum albumin.

RESULTS

After multivariable adjustment, though the relationship between BMI and risk of ADL decline was U-shaped among women, only those with BMI ≥25.0 showed a higher risk for ADL decline (OR 1.39, 95% CI 1.01-1.92) compared with the reference. The OR for death without observation of ADL decline was significantly lower for men with BMI ≥25.0 (OR 0.70, 95% CI 0.50-0.98).

CONCLUSIONS

This study suggests being overweight is a good predictor of future decline in ADL for women, whereas men with BMI 22.0-24.9 had lower risks of ADL decline. Appropriate management of weight in older women could prevent disabilities. Geriatr Gerontol Int 2018; 18: 799-805.