Tokashiki Kaori, Tozawa Masahiko, Iseki Chiho, Kohagura Kentaro, Kinjo Kozen, Takishita Shuichi, Iseki Kunitoshi
Department of Cardiovascular Medicine, Nephrology, and Neurology, Faculty of Medicine and Dialysis Unit, University Hospital of The Ryukyus and Okinawa General Health Maintenance Association, Okinawa, Japan.
Clin Exp Nephrol. 2009 Feb;13(1):55-60. doi: 10.1007/s10157-008-0085-y. Epub 2008 Oct 7.
Obesity and metabolic syndrome are risk factors for the development of chronic kidney disease (CKD). Few studies have examined the effect of change in body mass index (DeltaBMI) on CKD incidence in a general screening setting.
Subjects of this study were screenees that participated in the screening program of the Okinawa General Health Maintenance Association in 1993 and 2003 in Okinawa, Japan. Using identification number, birth date, sex, and other recorded identifiers, we identified 33,389 subjects among the 1993 screening participants (N = 143,948) who also participated in the 2003 screening. CKD was defined as estimated glomerular filtration rate <60 ml/min/1.73 m(2), according to the modification of diet in renal disease study equation. Obesity was defined as BMI > or = 25 kg/m(2).
CKD prevalence was 13.8% in 1993 and 22.4% in 2003. The incidence of developing CKD in 10 years was 15.5%. The effect of DeltaBMI on CKD incidence was evaluated after considering other confounding factors such as age, sex, blood pressure, BMI, fasting plasma glucose, and proteinuria. Median DeltaBMI was 1.0%. The adjusted odds ratio (95% CI) for the effect of DeltaBMI on CKD incidence was 1.111 (1.026-1.204, P < 0.01; entire study population), 1.271 (1.116-1.448, P = 0.0030; men), and 1.030 (0.931-1.139, NS; women), when DeltaBMI > or = 1% was taken as a reference. DeltaBMI was an independent predictor of CKD incidence.
The present results suggest that there was an inverse relationship between DeltaBMI and CKD incidence among screened subjects. The reasons for this observation are not clear, but careful follow-up for DeltaBMI is necessary, particularly in obese men with proteinuria.
肥胖和代谢综合征是慢性肾脏病（CKD）发生的危险因素。在一般筛查环境中，很少有研究探讨体重指数变化（DeltaBMI）对CKD发病率的影响。
本研究的受试者是1993年和2003年参加日本冲绳县综合健康维持协会筛查项目的受检者。利用识别号、出生日期、性别和其他记录的标识符，我们在1993年筛查参与者（N = 143,948）中确定了33,389名也参加了2003年筛查的受试者。根据肾脏病饮食改良研究方程，CKD定义为估计肾小球滤过率<60 ml/min/1.73 m²。肥胖定义为BMI≥25 kg/m²。
1993年CKD患病率为13.8%，2003年为22.4%。10年中发生CKD的发病率为15.5%。在考虑年龄、性别、血压、BMI、空腹血糖和蛋白尿等其他混杂因素后，评估了DeltaBMI对CKD发病率的影响。DeltaBMI中位数为1.0%。以DeltaBMI≥1%为参照时，DeltaBMI对CKD发病率影响的校正优势比（95%CI）在整个研究人群中为1.111（1.026 - 1.204，P < 0.01），男性为1.271（1.116 - 1.448，P = 0.0030），女性为1.030（0.931 - 1.139，无统计学意义）。DeltaBMI是CKD发病率的独立预测因素。
目前的结果表明，在受检者中DeltaBMI与CKD发病率之间存在负相关关系。这一观察结果的原因尚不清楚，但对DeltaBMI进行仔细随访是必要的，尤其是在有蛋白尿的肥胖男性中。
