Objective The objective was to investigate the incidence of late-onset giant cell arteritis (GCA) within the first year in patients diagnosed with polymyalgia rheumatica (PMR). Methods In this prospective study, treatment-naïve individuals with a new clinical diagnosis of PMR and without GCA symptoms underwent baseline assessments, including vascular ultrasonography and 2-[18F]fluoro-2-deoxy-D-glucose positron emission tomography computed tomography (FDG-PET/CT). To prevent biased inclusion, rapid referral clinics were established for all patients suspected of PMR. Additionally, the patients underwent GCA monitoring during clinical visits at weeks 8 and 10, which involved vascular ultrasonography and FDG-PET/CT scans. After one year, a follow-up visit was performed to confirm the PMR diagnosis and perform vascular ultrasonography. Results A final PMR diagnosis was assigned to 62 patients, excluding two patients with concurrent subclinical GCA and PMR at baseline, corresponding to a baseline prevalence of subclinical GCA of 3%. During the one-year follow-up, two PMR patients developed late-onset GCA corresponding to an incidence rate of 32 per 1000 person-years. One patient developed GCA 14 weeks after the PMR diagnosis, exhibiting cranial symptoms and positive vascular ultrasonography. The other patient presented with subclinical large vessel GCA at the one-year visit detected with vascular ultrasonography and confirmed by FDG-PET/CT. Conclusion This study is the first to demonstrate a low incidence rate of late-onset GCA in PMR patients within the first year, employing repeated imaging to exclude GCA at baseline and diagnose GCA during follow-up. Additionally, it provides evidence of a low prevalence of subclinical GCA across the entire PMR population. Trial registration ClinicalTrials.Gov, NCT04519580

中文翻译：

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风湿性多肌痛患者第一年晚发性巨细胞动脉炎的发生率低 - 一项重复影像学检查


目的 目的是调查风湿性多肌痛 （PMR） 患者第一年内迟发性巨细胞动脉炎 （GCA） 的发病率。方法 在这项前瞻性研究中，新临床诊断为 PMR 且无 GCA 症状的初治个体接受了基线评估，包括血管超声检查和 2-[18F] 氟-2-脱氧-D-葡萄糖正电子发射断层扫描计算机断层扫描 （FDG-PET/CT）。为防止偏倚纳入，为所有疑似 PMR 的患者建立了快速转诊诊所。此外，患者在第 8 周和第 10 周的临床就诊期间接受了 GCA 监测，包括血管超声检查和 FDG-PET/CT 扫描。一年后，进行随访以确认 PMR 诊断并进行血管超声检查。结果 将 62 例患者最终诊断为 PMR，不包括 2 例基线时并发亚临床 GCA 和 PMR 的患者，对应的亚临床 GCA 基线患病率为 3%。在 1 年随访期间，2 例 PMR 患者出现迟发性 GCA，发病率为 32/1000 人年。1 例患者在 PMR 诊断后 14 周发生 GCA，表现出颅脑症状和血管超声阳性。另一例患者在 1 年就诊时出现亚临床大血管 GCA，经血管超声检查发现并通过 FDG-PET/CT 确诊。结论 本研究首次证明 PMR 患者第一年内迟发性 GCA 发生率低，采用重复影像学检查在基线时排除 GCA，并在随访时诊断 GCA。此外，它提供了整个 PMR 人群中亚临床 GCA 患病率低的证据。 试验注册 ClinicalTrials.政府， NCT04519580