Cawthon Peggy M, Patel Sheena, Ewing Susan K, Lui Li-Yung, Cauley Jane A, Lyons Jennifer G, Fredman Lisa, Kado Deborah M, Hoffman Andrew R, Lane Nancy E, Ensrud Kristine E, Cummings Steven R, Orwoll Eric S
California Pacific Medical Center Research Institute, San Francisco, CA, USA.
Department of Epidemiology and Biostatistics, University of California, San Francisco, San Francisco, CA, USA.
JBMR Plus. 2017 Aug;1(1):31-35. doi: 10.1002/jbm4.10006. Epub 2017 Jul 10.
Low bone mineral density (BMD) is associated with increased mortality risk, yet the impact of BMD loss on mortality is relatively unknown. We hypothesized that greater BMD loss is associated with increased mortality risk in older men. Change in femoral neck BMD was assessed in 4400 Osteoporotic Fractures in Men (MrOS) study participants with two to three repeat dual-energy X-ray absorptiometry scans over an average of 4.6 ± 0.4 (mean ± SD) years. Change in femoral neck BMD was estimated using mixed effects models; men were grouped into three categories of BMD change: maintenance ( = 1087; change ≥ 0 g/cm); expected loss ( = 2768; change between 0 g/cm and <1 SD below mean change [>-0.034 g/cm]); and accelerated loss ( = 545; change 1 SD below mean change or worse [≤-0.034 g/cm]). Multivariate proportional hazards models adjusted for potential confounders estimated the risk of all-cause mortality over 8.1 ± 2.8 years following visit 2. Mortality was centrally adjudicated by physician review of death certificates. At visit 1, mean age was 72.9 ± 5.5 years. Men who maintained BMD were less likely to die during the subsequent follow-up period (33.7%) than men who had accelerated BMD loss (60.6%) ( < 0.001). Compared to men who had maintained BMD, those who had accelerated BMD loss had a 44% greater risk of mortality in multivariate-adjusted models (HR, 1.44; 95% CI, 1.23 to 1.68). Compared to men who had maintained BMD, there was no significant difference in mortality risk for men with expected loss of BMD (36.9% died) (multivariate HR, 1.00; 95% CI, 0.89 to 1.13). Further adjustment for visit 1 or visit 2 BMD measurement did not substantially alter these associations. Results for total hip BMD were similar. In conclusion, accelerated loss of BMD at the hip is a risk factor for mortality in men that is not explained by comorbidity burden, concurrent change in weight, or physical activity.
低骨矿物质密度(BMD)与死亡风险增加相关,但BMD丧失对死亡率的影响相对未知。我们假设,更大程度的BMD丧失与老年男性死亡风险增加相关。在4400名男性骨质疏松性骨折(MrOS)研究参与者中评估了股骨颈BMD的变化,这些参与者平均在4.6±0.4(均值±标准差)年的时间里接受了两到三次重复双能X线吸收测定扫描。使用混合效应模型估计股骨颈BMD的变化;男性被分为三类BMD变化:维持(n = 1087;变化≥0 g/cm²);预期丧失(n = 2768;变化在0 g/cm²和低于均值变化1个标准差之间[>-0.034 g/cm²]);以及加速丧失(n = 545;变化低于均值变化1个标准差或更差[≤-0.034 g/cm²])。在对潜在混杂因素进行调整的多变量比例风险模型中,估计了随访2后8.1±2.8年期间全因死亡风险。死亡率由医生对死亡证明的审查进行集中判定。在随访1时,平均年龄为72.9±5.5岁。与BMD加速丧失的男性(60.6%)相比,BMD维持的男性在随后随访期间死亡的可能性较小(33.7%)(P<0.001)。在多变量调整模型中,与BMD维持的男性相比,BMD加速丧失的男性死亡风险高44%(风险比,1.44;95%置信区间,1.23至1.68)。与BMD维持的男性相比,BMD预期丧失的男性死亡风险无显著差异(36.9%死亡)(多变量风险比,1.00;95%置信区间,0.89至1.13)。对随访1或随访2时的BMD测量值进行进一步调整并未实质性改变这些关联。全髋BMD的结果相似。总之,髋部BMD的加速丧失是男性死亡的一个风险因素,这不能用合并症负担、体重的同时变化或身体活动来解释。