Infective endocarditis is an uncommon but serious infection, where evidence for giving antibiotic prophylaxis before invasive dental procedures is inconclusive. In England, antibiotic prophylaxis was offered routinely to patients at risk of infective endocarditis until March 2008, when new guidelines aimed at reducing unnecessary antibiotic use were issued. We investigated whether changes in infective endocarditis incidence could be detected using electronic health records, assessing the impact of inclusion criteria/statistical model choice on inferences about the timing/type of any change. Using national data from Hospital Episode Statistics covering 1998–2017, we modelled trends in infective endocarditis incidence using three different sets of inclusion criteria plus a range of regression models, identifying the most likely date for a change in trends if evidence for one existed. We also modelled trends in the proportions of different organism groups identified during infection episodes, using secondary diagnosis codes and data from national laboratory records. Lastly, we applied non-parametric local smoothing to visually inspect any changes in trend around the guideline change date. Infective endocarditis incidence increased markedly over the study (22.2–41.3 per million population in 1998 to 42.0–67.7 in 2017 depending on inclusion criteria). The most likely dates for a change in incidence trends ranged from September 2001 (uncertainty interval August 2000–May 2003) to May 2015 (March 1999–January 2016), depending on inclusion criteria and statistical model used. For the proportion of infective endocarditis cases associated with streptococci, the most likely change points ranged from October 2008 (March 2006–April 2010) to August 2015 (September 2013–November 2015), with those associated with oral streptococci decreasing in proportion after the change point. Smoothed trends showed no notable changes in trend around the guideline date. Infective endocarditis incidence has increased rapidly in England, though we did not detect any change in trends directly following the updated guidelines for antibiotic prophylaxis, either overall or in cases associated with oral streptococci. Estimates of when changes occurred were sensitive to inclusion criteria and statistical model choice, demonstrating the need for caution in interpreting single models when using large datasets. More research is needed to explore the factors behind this increase.

中文翻译：

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在英格兰，NICE指南关于有创牙科程序中抗生素预防对感染性心内膜炎发生率的影响调查：电子健康记录研究。

感染性心内膜炎是一种罕见但严重的感染，尚无定论在侵入性牙科手术之前进行抗生素预防的证据。在英格兰，直到2008年3月发布了旨在减少不必要的抗生素使用的新指南后，才对有感染性心内膜炎风险的患者常规提供抗生素预防。我们调查了是否可以使用电子健康记录来检测感染性心内膜炎发生率的变化，评估纳入标准/统计模型选择对任何变化的时间/类型的推论的影响。利用1998-2017年《医院病情统计》中的国家数据，我们使用三组不同的纳入标准以及一系列回归模型对传染性心内膜炎的发病率趋势进行了建模，如果存在证据，则确定趋势变化的最可能日期。我们还使用二级诊断代码和来自国家实验室记录的数据，对感染发作期间确定的不同生物体比例的趋势进行了建模。最后，我们应用了非参数局部平滑法，以肉眼检查准则更改日期前后趋势的任何变化。在该研究中，感染性心内膜炎的发病率显着增加（根据纳入标准，1998年每百万人口中22.2-41.3增至2017年42.0-67.7）。发生趋势变化的最可能日期是2001年9月（不确定区间2000年8月至2003年5月）到2015年5月（1999年3月至2016年1月），具体取决于纳入标准和统计模型。对于与链球菌有关的感染性心内膜炎病例的比例，最可能的变化点是从2008年10月（2006年3月至2010年4月）至2015年8月（2013年9月至2015年11月），而与口腔链球菌有关的病例在变化后所占的比例下降点。平滑的趋势显示在准则日期前后趋势没有显着变化。在英格兰，传染性心内膜炎的发病率迅速增加，尽管我们没有直接遵循更新的抗生素预防指南（无论是整体还是与口服链球菌相关的病例）直接发现趋势变化。何时发生更改的估计值对包含标准和统计模型的选择敏感，这表明在使用大型数据集时解释单个模型时需要谨慎。