Chahine Lana M, Rosso Andrea, Troidl Ian, Ganguli Mary, Newman Anne, Cummings Steven, Studenski Stephanie, Lopresti Brian, Royse Sarah, Huppert Theodore, Redfern Mark, Sparto Patrick J, Bohnen Nico I, Rosano Caterina
Department of Neurology, School of Medicine, University of Pittsburgh, Pittsburgh, PA, USA.
Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA.
Aging Brain. 2025 Jun 20;8:100143. doi: 10.1016/j.nbas.2025.100143. eCollection 2025.
Identifying mechanisms that compensate for slow gait speed in older adults is crucial. Dopaminergic neurotransmission curbs deleterious associations of cerebrovascular disease with gait, but whether it compensates for peripheral systemic risk factors (PSRF) for gait slowing has not been studied. In this cross-sectional study of community-dwelling older adults, we examined the relationship between nigrostriatal dopaminergic terminal integrity and gait speed in individuals with and without ≥ 1 PSRF for gait slowing: obesity, joint pain, or reduced muscle strength. The primary outcome was gait speed cost (%GSC) on transition from even to uneven surface. Participants underwent dopaminergic imaging with dihydrotetrabenazine [C]DTBZ positron emission tomography. Among 197 individuals, (mean (SD) age 74.92 (4.53) years; 61.93 % female; 90.86 % White), 130 (65.99 %) had ≥ 1 PSRF. Relationship between posterior putamen [C]DTBZ binding and %GSC was modified by PSRF; in those with ≥ 1 PSRF (but not in those with no PSRF), posterior putamen [C]DTBZ binding was associated with %GSC (β = 0.198, p = 0.03) independent of potential confounders. This cross-sectional study indicates that higher striatal dopaminergic neurotransmission may compensate for the effects of PSRF on gait slowing.
确定能够补偿老年人步态速度减慢的机制至关重要。多巴胺能神经传递抑制了脑血管疾病与步态之间的有害关联，但它是否能补偿步态减慢的外周全身风险因素（PSRF）尚未得到研究。在这项针对社区居住老年人的横断面研究中，我们研究了黑质纹状体多巴胺能终末完整性与存在和不存在≥1种步态减慢PSRF（肥胖、关节疼痛或肌肉力量减弱）的个体的步态速度之间的关系。主要结局是从平坦表面过渡到不平坦表面时的步态速度成本（%GSC）。参与者接受了用二氢四苯嗪[C]DTBZ正电子发射断层扫描进行的多巴胺能成像。在197名个体中（平均（标准差）年龄74.92（4.53）岁；61.93%为女性；90.86%为白人），130名（65.99%）有≥1种PSRF。壳核后部[C]DTBZ结合与%GSC之间的关系因PSRF而改变；在有≥1种PSRF的个体中（但在没有PSRF的个体中并非如此），壳核后部[C]DTBZ结合与%GSC相关（β = 0.198，p = 0.03），独立于潜在混杂因素。这项横断面研究表明，较高的纹状体多巴胺能神经传递可能补偿PSRF对步态减慢的影响。
