Skipping Breakfast and Progression of Chronic Kidney Disease in the General Japanese Population: The Iki City Epidemiological Study of Atherosclerosis and Chronic Kidney Disease (ISSA-CKD).

INTRODUCTION: Breakfast-skipping habits are associated with adverse health outcomes including coronary heart disease, metabolic syndrome, and diabetes mellitus. However, it remains uncertain whether skipping breakfast affects chronic kidney disease (CKD) risk. This study aimed to examine the association between skipping breakfast and progression of CKD. METHODS: We retrospectively conducted a population-based cohort study using the data from the Iki City Epidemiological Study of Atherosclerosis and Chronic Kidney Disease (ISSA-CKD). Between 2008 and 2019, we included 922 participants aged 30 years or older who had CKD (estimated glomerular filtration rate <60 mL/min/1.73 m2 and/or proteinuria) at baseline. Breakfast skippers were defined as participants who skipped breakfast more than 3 times per week. The outcome was CKD progression defined as a decline of at least 30% in the estimated glomerular filtration rate (eGFR) from the baseline status. Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for CKD progression, adjusted for other CKD risk factors. RESULTS: During a follow-up period with a mean of 5.5 years, CKD progression occurred in 60 (6.5%) participants. The incidence rate (per 1,000 person-years) of CKD progression was 21.5 in the breakfast-skipping group and 10.7 in the breakfast-eating group (p = 0.029), respectively. The multivariable-adjusted HR (95% CI) for CKD progression was 2.60 (95% CI: 1.29-5.26) for the breakfast-skipping group (p = 0.028) compared with the group eating breakfast. There were no clear differences in the association of skipping breakfast with CKD progression in subgroup analyses by sex, age, obesity, hypertension, diabetes mellitus, baseline eGFR, and baseline proteinuria. CONCLUSION: Skipping breakfast was significantly associated with higher risk of CKD progression in the general Japanese population.

Relationship between abdominal circumference and the incidence of hyperuricemia in the general Japanese population.

In this study, we aimed to separately evaluate the relationship between waist circumference and the incidence of hyperuricemia in men and women in the general Japanese population. We performed a population-based longitudinal study using data from the annual health examination of residents of Iki City, Japan. A total of 5567 participants without hyperuricemia at baseline were included in the analysis. The men and women were placed into groups according to the tertile of waist circumference. The outcome was incident hyperuricemia (uric acid > 416 µmol/L [7.0 mg/dL]). The relationship between waist circumference and the incidence of hyperuricemia was investigated using Cox proportional hazards models. During the follow-up period, hyperuricemia developed in 697 people (551 men and 146 women). The incidence (per 1000 person-years) of hyperuricemia increased with increasing waist circumference in the men (34.9 for tertile 1, 49.9 for tertile 2 and 63.3 for tertile 3; Ptrend < 0.001) and women (5.5 for tertile 1, 6.3 for tertile 2 and 11.9 for tertile 3; Ptrend < 0.001). Significant associations were identified after adjustment for potential confounders (men: Ptrend < 0.001; women: Ptrend = 0.014). In conclusion, both men and women with larger waist circumferences were at higher risks of subsequent hyperuricemia.