AIMS: It has been recognized that blood pressure shows a seasonal variation, but it remains unknown whether diabetic nephropathy shows a seasonal variation. In the present study, we investigated the change in urinary albumin/creatinine ratio in relation to the season in Japanese patients with Type 2 diabetes. METHODS: A total of 430 subjects (275 male, 155 female) with Type 2 diabetes and early nephropathy (defined by UACR 30-300 mg/g creatinine) were included. One year was divided into four seasons and each season was defined as winter (December-February), spring (March-May), summer (June-August), and fall (September-November), and systolic and diastolic blood pressure, serum creatinine levels, and the urinary albumin/creatinine ratio were examined. The estimated glomerular filtration rate was also calculated and evaluated. RESULTS: The mean age (± SE) was 64.8 ± 0.8 years. The mean systolic blood pressure was significantly higher in winter than in summer (136 ± 0.68 vs. 133 ± 0.68 mmHg, P < 0.001). The urinary albumin/creatinine ratio showed a significantly higher value in winter than in summer (72.8 ± 4.4 vs. 54.6 ± 3.4 mg/g creatinine, P < 0.001). The curve of seasonal variation of this ratio showed a similar change to that of systolic blood pressure. No significant seasonal variation was observed in estimated glomerular filtration rate and diastolic blood pressure. CONCLUSIONS: Our results suggest that there is a hitherto unknown seasonal variation in the urinary albumin/creatinine ratio, and that it may be necessary to consider this seasonal change, especially when performing an intervention study of nephropathy.
AIMS: It has been recognized that blood pressure shows a seasonal variation, but it remains unknown whether diabetic nephropathy shows a seasonal variation. In the present study, we investigated the change in urinary albumin/creatinine ratio in relation to the season in Japanese patients with Type 2 diabetes. METHODS: A total of 430 subjects (275 male, 155 female) with Type 2 diabetes and early nephropathy (defined by UACR 30-300 mg/g creatinine) were included. One year was divided into four seasons and each season was defined as winter (December-February), spring (March-May), summer (June-August), and fall (September-November), and systolic and diastolic blood pressure, serum creatinine levels, and the urinary albumin/creatinine ratio were examined. The estimated glomerular filtration rate was also calculated and evaluated. RESULTS: The mean age (± SE) was 64.8 ± 0.8 years. The mean systolic blood pressure was significantly higher in winter than in summer (136 ± 0.68 vs. 133 ± 0.68 mmHg, P < 0.001). The urinary albumin/creatinine ratio showed a significantly higher value in winter than in summer (72.8 ± 4.4 vs. 54.6 ± 3.4 mg/g creatinine, P < 0.001). The curve of seasonal variation of this ratio showed a similar change to that of systolic blood pressure. No significant seasonal variation was observed in estimated glomerular filtration rate and diastolic blood pressure. CONCLUSIONS: Our results suggest that there is a hitherto unknown seasonal variation in the urinary albumin/creatinine ratio, and that it may be necessary to consider this seasonal change, especially when performing an intervention study of nephropathy.
Authors: Julia M Hermann; Joachim Rosenbauer; Axel Dost; Claudia Steigleder-Schweiger; Wieland Kiess; Christof Schöfl; Reinhard W Holl Journal: J Clin Hypertens (Greenwich) Date: 2015-12-10 Impact factor: 3.738