Derivation and validation of a novel method to subgroup patients with functional dyspepsia: beyond upper...

Conventionally, patients with functional dyspepsia are subgrouped based on upper gastrointestinal symptoms, according to the Rome criteria. However, psychological co-morbidity and extraintestinal symptoms are also relevant to functional gastrointestinal disorders.

To investigate whether it is possible to subgroup people with functional dyspepsia using factors beyond upper gastrointestinal symptoms.

We collected demographic, symptom and psychological health data from adult subjects meeting the Rome III criteria for functional dyspepsia in two secondary care cross-sectional surveys in Canada and the UK. We performed latent class analysis, a method of model-based clustering, to identify specific subgroups (clusters). For each cluster, we drew a radar plot, and compared these by visual inspection, describing cluster characteristics.

In total, 400 individuals met Rome III criteria for functional dyspepsia in the Canadian cohort, and 262 the UK cohort. A four-cluster model was the optimum solution and the characteristics of the clusters were almost identical between the two cohorts. The clusters were defined by a pattern of gastrointestinal symptoms and were further differentiated by the extent of extraintestinal and psychological co-morbidity. Cluster 1 (mean age 46.7 years, 66.7% female) consisted of epigastric pain and nausea with high psychological burden, cluster 2 (mean age 41.5 years, 77.7% female) high overall gastrointestinal symptom severity with high psychological burden, cluster 3 (45.8 years, 67.2% female) oesophageal symptoms and early satiety with low psychological burden, and cluster 4 (mean age 40.4 years, 71.5% female) postprandial fullness with low psychological burden. We validated the model derived using the Canadian study population externally by applying it to the UK dataset. We demonstrated reproducibility; it would perform similarly when applied to a different dataset.

Latent class analysis identified four distinct functional dyspepsia subgroups characterised by varying degrees of gastrointestinal symptoms, extraintestinal symptoms and psychological co-morbidity. Further research is needed to assess whether they might be used to direct treatment.