Department of Research and Evaluation, Kaiser Permanente Southern California, 100 S. Los Robles Ave, 2nd Floor, Pasadena, CA, 91101, USA.
Division of Nephrology and Hypertension, Kaiser Permanente Los Angeles Medical Center, Los Angeles, CA, USA.
Osteoporos Int. 2019 Apr;30(4):853-861. doi: 10.1007/s00198-018-04832-4. Epub 2019 Jan 11.
Chronic hyponatremia may contribute to decreased bone density. We studied 341,003 men and women who underwent DXA testing and observed that individuals with chronic hyponatremia (sodium < 135 mEq/L) had an 11% greater likelihood of having osteoporosis. There was a dose-dependent effect with lower sodium and stronger association with osteoporosis.
Chronic hyponatremia has been associated with both neurologic deficits and increased risk of gait abnormalities leading to falls and resultant bone fractures. Whether chronic hyponatremia contributes to decreased bone density is uncertain. We evaluated whether chronic, mild hyponatremia based on serial sodium measurements was associated with increased risk of osteoporosis within a large, ethnically diverse population.
This is a retrospective cohort study between January 1, 1998 and December 31, 2014 within Kaiser Permanente Southern California, an integrated healthcare delivery system. Men and women were aged ≥ 55 years with ≥ 2 serum sodium measurements prior to dual-energy X-ray absorptiometry (DXA) testing. Time-weighted (TW) mean sodium values were calculated by using the proportion of time (weight) elapsed between sodium measurements and defined as < 135 mEq/L. Osteoporosis defined as any T-score value ≤ - 2.5 of lumbar spine, femoral neck, or hip.
Among 341,003 individuals with 3,330,903 sodium measurements, 11,539 (3.4%) had chronic hyponatremia and 151,505 (44.4%) had osteoporosis. Chronic hyponatremic individuals had an osteoporosis RR (95% CI) of 1.11 (1.09, 1.13) compared to those with normonatremia. A TW mean sodium increase of 3 mEq/L was associated with a lower risk of osteoporosis [adjusted RR (95% CI) 0.95 (0.93, 0.96)]. A similar association was observed when the arithmetic mean sodium value was used for comparison.
We observed a modest increase in risk for osteoporosis in people with chronic hyponatremia. There was also a graded association between higher TW mean sodium values and lower risk of osteoporosis. Our findings underscore the premise that chronic hyponatremia may lead to adverse physiological effects and responses which deserves better understanding.
慢性低钠血症可能导致骨密度降低。我们研究了 341003 名接受 DXA 检测的男性和女性，发现慢性低钠血症（钠<135mEq/L）患者骨质疏松症的可能性增加 11%。钠越低，与骨质疏松症的关联越强，呈剂量依赖性。
慢性低钠血症与神经功能缺陷以及步态异常风险增加有关，导致跌倒和由此产生的骨折。慢性低钠血症是否导致骨密度降低尚不确定。我们评估了基于系列钠测量的慢性、轻度低钠血症是否与大型、种族多样化人群中骨质疏松症的风险增加有关。
这是 1998 年 1 月 1 日至 2014 年 12 月 31 日期间在凯撒永久南加州的一项回顾性队列研究，这是一个综合医疗服务系统。年龄≥55 岁的男性和女性在双能 X 射线吸收法（DXA）检测前至少有 2 次血清钠测量值。通过使用钠测量值之间的时间（权重）比例计算时间加权（TW）平均钠值，并定义为<135mEq/L。骨质疏松症定义为腰椎、股骨颈或髋部任何 T 评分值≤-2.5。
在 341003 名个体中，有 3330903 次钠测量值，11539 名（3.4%）患有慢性低钠血症，151505 名（44.4%）患有骨质疏松症。与正常钠血症患者相比，慢性低钠血症患者的骨质疏松症 RR（95%CI）为 1.11（1.09，1.13）。TW 平均钠升高 3mEq/L 与骨质疏松症风险降低相关[校正 RR（95%CI）0.95（0.93，0.96）]。当使用算术平均钠值进行比较时，也观察到类似的关联。
我们观察到慢性低钠血症患者的骨质疏松症风险略有增加。TW 平均钠值越高，与骨质疏松症风险降低之间也存在分级关联。我们的研究结果强调了慢性低钠血症可能导致不良生理效应和反应的前提，这值得更好地理解。
