BACKGROUND Patients with COVID-19 are follow-up in primary care and long COVID is scarcely defined. The study aim was to describe SARS-CoV-2 pneumonia and cut-offs for defining long COVID in primary care follow-up patients. METHODS A retrospective observational study in primary care in Madrid, Spain, was conducted. Data was collected during 6 months (April to September) in 2020, during COVID-19 first wave, from patients ≥ 18 years with SARS-CoV-2 pneumonia diagnosed. Variables: sociodemographic, comorbidities, COVID-19 symptoms and complications, laboratory test and chest X-ray. Descriptive statistics were used, mean (standard deviation (SD)) and medians (interquartile range (IQR)) respectively. Differences were detected applying X2 test, Student's T-test, ANOVA, Wilcoxon-Mann-Whitney or Kruskal-Wallis depending on variable characteristics. RESULTS 155 patients presented pneumonia in day 7.8 from the onset (79.4% were hospitalized, median length of 7.0 days (IQR: 3.0, 13.0)). After discharge, the follow-up lasted 54.0 median days (IQR 42.0, 88.0) and 12.2 mean (SD 6.4) phone calls were registered per patient. The main symptoms and their duration were: cough (41.9%, 12 days), dyspnoea (31.0%, 15 days), asthenia (26.5%, 21 days). Different cut-off points were applied for long COVID and week 4 was considered the best milestone (28.3% of the sample still had symptoms after week 4) versus week 12 (8.3%). Patients who still had symptoms >4 weeks follow-up took place over 81.0 days (IQR: 50.5, 103.0), their symptoms were more prevalent and lasted longer than those ≤ 4 weeks: cough (63.6% 30 days), dyspnoea (54.6%, 46 days), and asthenia (56.8%, 29 days). Embolism was more frequent in patients who still had symptoms >4 weeks than those with symptoms ≤4 weeks (9.1% vs 1.8%, p value 0.034). CONCLUSION Most patients with SARS-CoV-2 pneumonia recovered during the first 4 weeks from the beginning of the infection. The cut-off point to define long COVID, as persisting symptoms, should be between 4 to 12 weeks from the onset of the symptoms.

中文翻译：

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初级保健中的 SARS-CoV-2 肺炎随访和长期新冠肺炎：马德里市的一项回顾性观察研究。


背景 COVID-19 患者在初级保健机构接受随访，长期 COVID 几乎没有定义。该研究的目的是描述 SARS-CoV-2 肺炎以及定义初级保健随访患者中长期新冠肺炎的临界点。方法 在西班牙马德里的初级保健中进行了一项回顾性观察研究。数据是在 2020 年 6 个月（4 月至 9 月）期间，即 COVID-19 第一波期间，从诊断为 SARS-CoV-2 肺炎的 18 岁以上患者中收集的。变量：社会人口统计学、合并症、COVID-19 症状和并发症、实验室检查和胸部 X 光检查。分别使用了描述性统计、平均值（标准差（SD））和中位数（四分位距（IQR））。根据变量特征，应用 X2 检验、学生 T 检验、方差分析、Wilcoxon-Mann-Whitney 或 Kruskal-Wallis 检测差异。结果 155 名患者在发病后第 7.8 天出现肺炎（79.4% 住院，中位住院时间为 7.0 天（IQR：3.0、13.0））。出院后，随访持续中位数 54.0 天（IQR 42.0、88.0），每位患者登记平均 12.2 次电话（SD 6.4）。主要症状及其持续时间为：咳嗽（41.9%，12天）、呼吸困难（31.0%，15天）、乏力（26.5%，21天）。对于长期新冠肺炎应用了不同的截止点，第 4 周被认为是最佳里程碑（28.3% 的样本在第 4 周后仍然有症状），而第 12 周 (8.3%) 则被认为是最佳里程碑。 >4周仍有症状的患者随​​访时间超过81.0天（IQR：50.5, 103.0），他们的症状比≤4周的患者更普遍且持续时间更长：咳嗽（63.6% 30天）、呼吸困难（54.6%） ，46 天）和无力（56.8%，29 天）。 >4周仍有症状的患者比症状≤4周的患者发生栓塞的频率更高（9.1% vs 1.8%，p 值 0.034）。结论 大多数 SARS-CoV-2 肺炎患者在感染开始后的前 4 周内康复。将长期新冠病毒定义为持续症状的分界点应为症状出现后 4 至 12 周。