Diabetes Center, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
Diabetes Res Clin Pract. 2010 Apr;88(1):65-70. doi: 10.1016/j.diabres.2009.12.011. Epub 2010 Jan 4.
We examined whether glycated hemoglobin (HbA(1C)) levels of Japanese diabetic patients showed seasonal fluctuations.
Subjects included 2511 diabetic patients who regularly visited a single diabetic outpatient clinic for 10 years. A total of 253,477 HbA(1C) measurements, as well as sex, age, BMI, type of diabetes, and mode of therapy were extracted from a hospital-based database. For the cross-sectional and longitudinal analyses, average monthly HbA(1C) values of subjects and amplitudes of seasonal fluctuations were calculated. For the time-series analysis, seasonal adjustment factors of each subject were classified as complete, incomplete, or no fluctuation.
Subjects showed a clear seasonal fluctuation of HbA(1C) levels, with highest levels in March (7.69%) and lowest levels in August (7.46%; p<0.001). The amplitudes of the seasonal fluctuations were associated with the mean HbA(1C) levels. The time-series analysis showed that 78.3% of patients had complete or incomplete seasonal fluctuations. HbA(1C) levels were highest in winter-spring and lowest in summer-autumn in most patients; however, some patients showed a reverse pattern.
Seasonal fluctuations of HbA(1C) levels were recognized in most of the Japanese diabetic patients. Physiological or metabolic factors related to temperature may be the main cause of seasonal fluctuations in HbA(1C) levels.
我们研究了日本糖尿病患者的糖化血红蛋白（HbA(1C)）水平是否存在季节性波动。
研究对象包括 2511 名定期到一家糖尿病门诊就诊 10 年的糖尿病患者。从医院数据库中提取了 253477 次 HbA(1C)测量值、性别、年龄、BMI、糖尿病类型和治疗方式。为了进行横断面和纵向分析，计算了受试者的平均每月 HbA(1C)值和季节性波动幅度。为了进行时间序列分析，将每个受试者的季节性调整因子分类为完全、不完全或无波动。
受试者的 HbA(1C)水平存在明显的季节性波动，3 月最高（7.69%），8 月最低（7.46%；p<0.001）。季节性波动幅度与平均 HbA(1C)水平相关。时间序列分析显示，78.3%的患者存在完全或不完全的季节性波动。大多数患者的 HbA(1C)水平冬季-春季最高，夏季-秋季最低；然而，一些患者表现出相反的模式。
大多数日本糖尿病患者的 HbA(1C)水平存在季节性波动。与温度相关的生理或代谢因素可能是 HbA(1C)水平季节性波动的主要原因。
