BACKGROUND The diagnostic assessment of abdominal symptoms in primary care presents a challenge. Evidence is needed about the positive predictive values (PPVs) of abdominal symptoms for different cancers and inflammatory bowel disease (IBD). METHODS AND FINDINGS Using data from The Health Improvement Network (THIN) in the United Kingdom (2000-2017), we estimated the PPVs for diagnosis of (i) cancer (overall and for different cancer sites); (ii) IBD; and (iii) either cancer or IBD in the year post-consultation with each of 6 abdominal symptoms: dysphagia (n = 86,193 patients), abdominal bloating/distension (n = 100,856), change in bowel habit (n = 106,715), rectal bleeding (n = 235,094), dyspepsia (n = 517,326), and abdominal pain (n = 890,490). The median age ranged from 54 (abdominal pain) to 63 years (dysphagia and change in bowel habit); the ratio of women/men ranged from 50%:50% (rectal bleeding) to 73%:27% (abdominal bloating/distension). Across all studied symptoms, the risk of diagnosis of cancer and the risk of diagnosis of IBD were of similar magnitude, particularly in women, and younger men. Estimated PPVs were greatest for change in bowel habit in men (4.64% cancer and 2.82% IBD) and for rectal bleeding in women (2.39% cancer and 2.57% IBD) and lowest for dyspepsia (for cancer: 1.41% men and 1.03% women; for IBD: 0.89% men and 1.00% women). Considering PPVs for specific cancers, change in bowel habit and rectal bleeding had the highest PPVs for colon and rectal cancer; dysphagia for esophageal cancer; and abdominal bloating/distension (in women) for ovarian cancer. The highest PPVs of abdominal pain (either sex) and abdominal bloating/distension (men only) were for non-abdominal cancer sites. For the composite outcome of diagnosis of either cancer or IBD, PPVs of rectal bleeding exceeded the National Institute of Health and Care Excellence (NICE)-recommended specialist referral threshold of 3% in all age-sex strata, as did PPVs of abdominal pain, change in bowel habit, and dyspepsia, in those aged 60 years and over. Study limitations include reliance on accuracy and completeness of coding of symptoms and disease outcomes. CONCLUSIONS Based on evidence from more than 1.9 million patients presenting in primary care, the findings provide estimated PPVs that could be used to guide specialist referral decisions, considering the PPVs of common abdominal symptoms for cancer alongside that for IBD and their composite outcome (cancer or IBD), taking into account the variable PPVs of different abdominal symptoms for different cancers sites. Jointly assessing the risk of cancer or IBD can better support decision-making and prompt diagnosis of both conditions, optimising specialist referrals or investigations, particularly in women.

中文翻译：

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英国超过 190 万初级保健患者对 6 种常见腹部症状的不同癌症和炎症性肠病的预测值：一项队列研究。

背景 初级保健中腹部症状的诊断评估是一项挑战。需要关于不同癌症和炎症性肠病 (IBD) 的腹部症状的阳性预测值 (PPV) 的证据。方法和发现 使用来自英国健康改善网络 (THIN) 的数据（2000-2017），我们估计了诊断 (i) 癌症（总体和不同癌症部位）的 PPV；(ii) 炎症性肠病；(iii) 癌症或 IBD 在咨询后的一年内出现 6 种腹部症状：吞咽困难（n = 86,193 名患者）、腹胀/腹胀（n = 100,856 名）、排便习惯改变（n = 106,715 名）、直肠出血 (n = 235,094)、消化不良 (n = 517,326) 和腹痛 (n = 890,490)。中位年龄从 54 岁（腹痛）到 63 岁（吞咽困难和排便习惯改变）不等；男女比例从 50%:50%（直肠出血）到 73%:27%（腹胀/腹胀）不等。在所有研究的症状中，诊断为癌症的风险和诊断为 IBD 的风险具有相似的程度，尤其是在女性和年轻男性中。估计的 PPV 在男性排便习惯改变（4.64% 癌症和 2.82% IBD）和女性直肠出血（2.39% 癌症和 2.57% IBD）和消化不良方面最低（癌症：1.41% 男性和 1.03% 女性） ; 对于 IBD：0.89% 男性和 1.00% 女性）。考虑到特定癌症的 PPV，排便习惯改变和直肠出血对结肠癌和直肠癌的 PPV 最高；食道癌吞咽困难；卵巢癌的腹胀/腹胀（女性）。腹痛（无论性别）和腹胀/腹胀（仅限男性）的最高 PPV 是针对非腹部癌症部位。对于癌症或 IBD 诊断的复合结果，直肠出血的 PPV 超过了美国国家健康与护理卓越研究所 (NICE) 推荐的所有年龄性别阶层的专家转诊阈值 3%，腹痛的 PPV 也是如此， 60 岁及以上人群的排便习惯改变和消化不良。研究局限性包括对症状和疾病结果编码的准确性和完整性的依赖。结论 基于超过 190 万初级保健患者的证据，研究结果提供了估计的 PPV，可用于指导专家转诊决策，考虑癌症常见腹部症状的 PPV 以及 IBD 的 PPV 及其复合结果（癌症或 IBD），同时考虑不同癌症部位的不同腹部症状的可变 PPV。联合评估癌症或 IBD 的风险可以更好地支持决策和及时诊断这两种情况，优化专家转诊或调查，特别是在女性中。