Department of Internal Medicine III, University of Jena, Jena, Germany.
Nephrol Dial Transplant. 2011 Dec;26(12):4017-23. doi: 10.1093/ndt/gfr185. Epub 2011 Apr 14.
Diabetic nephropathy is the most common disease leading to end-stage renal disease (ESRD) in many countries including Germany. Some previous studies, mainly from the US, suggest that low socioeconomic status (SES) may increase the risk of ESRD. No data are available whether the SES influences the development of diabetic nephropathy in patients with diabetes mellitus in Germany.
This cross-sectional study was performed on patients treated at a large university outpatient department for endocrinology and metabolic diseases. A total of 174 patients with type 1 and 651 patients with type 2 diabetes and chronic preterminal diabetic nephropathy were studied [mainly chronic kidney disease (CKD) Stages 2 and 3]. Only very few CKD Stage 5 patients were included. Patients with acute kidney injury or abnormal urinary sediment were excluded. Patients were asked about their social status using a questionnaire. Social status was determined by three components: education, highest professional position achieved and household net income. Each component was assessed by a score with 1 to 7 points to generate a total score with a minimum of 3 up to maximum of 21 points. Smoking habits were also assessed by questionnaire. HbA1c, systolic and diastolic blood pressure and body mass index from the last observation were recorded. Estimated glomerular filtration rate (eGFR) was calculated according to the modified equation 7 MDRD formula. Patients were grouped into the CKD stages according to eGFR and presence of albuminuria. Multivariate analysis was used for data analysis.
Patients were grouped in tertiles according to their social status (Tertile 1: 307, Tertile 2: 269, Tertile 3: 269 patients). The majority of type 1 (50.9%) and type 2 (64.9%) patients were in CKD Stages 2 and 3. Multivariate analysis revealed that SES is an independent predictor of renal function in all patients as well as in type 2 diabetic patients with diabetic nephropathy. This relationship was independent of smoking behaviour, duration of diabetes and HbA1c values. There was no association between renal function and SES in type 1 diabetic patients, but a type 2 error caused by low patient number cannot be excluded. Furthermore, no significant association between SES and albuminuria (defined ≥20 mg/L) existed. There was no significant difference in the number of visits to the clinic in regard to SES excluding referral bias.
A lower SES was associated with the presence of diabetic nephropathy in patients with type 2 diabetes in a German population. The causes for this association are likely multiple.
在包括德国在内的许多国家，糖尿病肾病是导致终末期肾病（ESRD）的最常见疾病。一些先前的研究主要来自美国，表明社会经济地位（SES）较低可能会增加 ESRD 的风险。目前尚无数据表明 SES 是否会影响德国糖尿病患者糖尿病肾病的发展。
本横断面研究在一家大型大学内分泌和代谢疾病门诊对患者进行。共研究了 174 例 1 型糖尿病患者和 651 例 2 型糖尿病合并慢性终末期糖尿病肾病患者[主要为慢性肾脏病（CKD）第 2 期和第 3 期]。仅纳入极少数 CKD 第 5 期患者。排除急性肾损伤或尿液异常的患者。使用问卷询问患者的社会地位。社会地位由三个组成部分确定：教育程度、所获得的最高职业职位和家庭净收入。每个组成部分都用 1 到 7 分进行评估，以生成最低 3 分最高 21 分的总分。吸烟习惯也通过问卷进行评估。记录最后一次观察时的糖化血红蛋白（HbA1c）、收缩压和舒张压以及体重指数。根据改良 MDRD 公式计算估算的肾小球滤过率（eGFR）。根据 eGFR 和白蛋白尿的存在，将患者分为 CKD 期。使用多元分析进行数据分析。
根据社会地位将患者分为三分位（三分位 1：307 例，三分位 2：269 例，三分位 3：269 例）。大多数 1 型（50.9%）和 2 型（64.9%）患者处于 CKD 第 2 期和第 3 期。多元分析表明，SES 是所有患者以及患有糖尿病肾病的 2 型糖尿病患者肾功能的独立预测因子。这种关系独立于吸烟行为、糖尿病病程和 HbA1c 值。1 型糖尿病患者的肾功能与 SES 之间无关联，但由于患者数量少可能存在二类错误。此外，SES 与白蛋白尿（定义为≥20mg/L）之间也没有显著关联。排除转诊偏倚后，SES 与就诊次数之间没有显著差异。
在德国人群中，2 型糖尿病患者 SES 较低与糖尿病肾病的发生有关。这种关联的原因可能是多方面的。
