Medical School, University of Aberdeen, Aberdeen, UK.
Institute of Applied Health Sciences, University of Aberdeen, Aberdeen, UK.
BMC Fam Pract. 2020 May 6;21(1):78. doi: 10.1186/s12875-020-01149-2.
Ankylosing spondylitis (AS) often has a long period from first symptom presentation to diagnosis. We examined the occurrence of symptoms, prescriptions and diagnostic tests in primary care electronic records over time prior to a diagnosis of AS.
Nested case-control study using anonymised primary care electronic health records from Scotland. Cases were 74 adults with a first diagnosis of AS between 2000 and 2010. Controls were matched for age, sex and GP practice: (a) 296 randomly selected adults (b) 169 adults whose records contained codes indicating spinal conditions or symptoms. We extracted clinical features (symptoms, AS-related disorders, prescriptions and diagnostic tests). Conditional logistic regression was used to examine the association between clinical features (both individually and in combinations) and diagnosis of AS. We examined the associations between clinical features and diagnosis over time prior to diagnosis.
Several new composite pointers were predictive of AS: including distinct episodes of axial pain separated by more than 6 months (OR 12.7, 95% CI 4.7 to 34.6); the occurrence of axial pain with and tendon symptoms within the same year (OR 21.7, 95% CI 2.6 to 181.5); and the co-occurrence (within 30 days) of axial pain and a prescription for nonsteroidal anti-inflammatory drug (OR 10.4, 95%CI 4.9 to 22.1). Coded episodes of axial pain increased steadily over the 3 years before diagnosis. In contrast, large joint symptoms and enthesopathy showed little or no time trend prior to diagnosis.
We identified novel composite pointers to a diagnosis of AS in GP records. These may represent valuable targets for diagnostic support systems.
强直性脊柱炎（AS）从首次出现症状到确诊往往需要很长时间。我们研究了在 AS 确诊之前，一段时间内初级保健电子病历中症状、处方和诊断性检查的发生情况。
采用苏格兰匿名初级保健电子健康记录的巢式病例对照研究。病例为 2000 年至 2010 年间首次确诊为 AS 的 74 名成年人。对照者按年龄、性别和全科医生实践进行匹配：（a）随机选择的 296 名成年人；（b）169 名记录中有脊柱疾病或症状编码的成年人。我们提取了临床特征（症状、与 AS 相关的疾病、处方和诊断性检查）。采用条件逻辑回归分析，研究了临床特征（单独和组合）与 AS 诊断之间的关系。我们还研究了在确诊之前，这些临床特征与诊断之间的时间关联。
多个新的综合指标与 AS 具有预测性：包括间隔超过 6 个月的不同轴向疼痛发作（比值比 12.7，95%可信区间 4.7 至 34.6）；同一年内出现轴向疼痛和肌腱症状（比值比 21.7，95%可信区间 2.6 至 181.5）；以及轴向疼痛和非甾体抗炎药处方同时发生（比值比 10.4，95%可信区间 4.9 至 22.1）。在确诊前的 3 年中，编码的轴向疼痛发作逐渐增加。相比之下，大关节症状和肌腱附着病在确诊前几乎没有或没有时间趋势。
我们在全科医生记录中发现了诊断 AS 的新的综合指标。这些可能是诊断支持系统的有价值的目标。
