Irritable Bowel Syndrome (IBS) is a poorly understood public health problem that affects a significant portion of the population. Despite the fact that co-morbidity can influence diagnosis and therapy, there are few studies on diagnosed and registered co-morbidity in IBS patients in primary care. The researchers used data from a county-wide computerised medical record system to compare co-morbidity among IBS patients to age- and sex-matched controls from the general population. Irritable Bowel Syndrome (IBS) is a chronic gastrointestinal disorder that is linked to a lower quality of life and greater healthcare utilisation. Health self-ratings have been shown to be a reliable predictor of health outcomes. In both IBS and non-IBS patients, a lack of gastrointestinal symptoms, a high sense of coherence, and a younger age were linked to higher self-rated health. The examination of diagnoses from the HCR revealed a broad spectrum of common co-morbidity and significantly more physician-recorded diagnoses among IBS-patients in comparison to the control group in this population-based case–control study.