Department 'Scuola Medica Salernitana', University of Salerno, Baronissi, Italy.
Unit of Nephrology and Hypertension, University Hospital, Salerno, Italy.
Nephrol Dial Transplant. 2018 Feb 1;33(2):274-283. doi: 10.1093/ndt/gfw426.
Research data are limited on indices of osmotic equilibrium and of kidney concentrating activity (KCA). This study investigated correlates and prognostic power of these indices in a sample of the general population.
Urine osmolality (U-osm), plasma osmolality (P-osm), plasma creatinine and other variables were measured by the Gubbio Study for the 1988-92 exam (baseline). Plasma creatinine and other variables were re-measured in the 2001-07 exam (follow-up). KCA was assessed as the U-osm/P-osm ratio and kidney function as estimated glomerular filtration rate (eGFR).
Baseline data were complete in 4220 adults, of whom 852 died before follow-up and 2795 participated in the follow-up. At baseline, the following independent cross-sectional associations were identified: female sex and higher urine flow with lower values of U-osm, P-osm and U-osm/P-osm ratio (P < 0.01); obesity with higher values of U-osm, P-osm and U-osm/P-osm ratio (P < 0.01); older age and lower eGFR with lower U-osm, lower U-osm/P-osm ratio and higher P-osm (P < 0.05); hypertension and smoking with lower U-osm and lower U-osm/P-osm ratio (P < 0.05) but not with P-osm. From baseline to follow-up, the annualized rate was 1.26% for mortality and -0.74 ± 0.76 mL/min × 1.73 m2 for eGFR change. Mortality was independently predicted by baseline U-osm and baseline U-osm/P-osm ratio (hazard ratio for one higher standard deviation was ≤0.91, 95% confidence interval was ≤0.97, P < 0.01), but not by baseline P-osm. The eGFR change was not independently predicted by baseline values of U-osm, P-osm and U-osm/P-osm ratio (P ≥ 0.4).
Sex, age, obesity, eGFR, urine flow, hypertension and smoking independently associated with U-osm and KCA. U-osm and KCA independently predicted mortality, but not kidney function change over time.
关于渗透平衡和肾脏浓缩功能（KCA）的研究数据有限。本研究旨在调查一般人群样本中这些指标的相关性和预后价值。
尿渗透压（U-osm）、血浆渗透压（P-osm）、血浆肌酐和其他变量由 Gubbio 研究在 1988-92 年的考试（基线）中测量。在 2001-07 年的考试（随访）中重新测量了血浆肌酐和其他变量。KCA 被评估为 U-osm/P-osm 比值，肾功能被评估为估计肾小球滤过率（eGFR）。
4220 名成年人的基线数据完整，其中 852 人在随访前死亡，2795 人参加了随访。在基线时，发现以下独立的横断面关联：女性和更高的尿量与较低的 U-osm、P-osm 和 U-osm/P-osm 比值相关（P<0.01）；肥胖与较高的 U-osm、P-osm 和 U-osm/P-osm 比值相关（P<0.01）；年龄较大和 eGFR 较低与较低的 U-osm、较低的 U-osm/P-osm 比值和较高的 P-osm 相关（P<0.05）；高血压和吸烟与较低的 U-osm 和较低的 U-osm/P-osm 比值相关（P<0.05），但与 P-osm 无关。从基线到随访，死亡率的年化率为 1.26%，eGFR 变化的年化率为-0.74±0.76mL/min×1.73 m2。死亡率独立地与基线 U-osm 和基线 U-osm/P-osm 比值相关（每增加一个标准差的危险比为≤0.91，95%置信区间为≤0.97，P<0.01），但与基线 P-osm 无关。eGFR 变化与基线 U-osm、P-osm 和 U-osm/P-osm 比值无独立相关性（P≥0.4）。
性别、年龄、肥胖、eGFR、尿量、高血压和吸烟与 U-osm 和 KCA 独立相关。U-osm 和 KCA 独立地预测死亡率，但不能预测随时间推移的肾功能变化。
