Comorbidity, healthcare utilisation and process of care measures in patients with congenital heart disease in the UK: cross-sectional, population-based study with case-control analysis

Objective: To determine the prevalence of comorbidities, patterns of healthcare utilisation and primary care recording of clinical indicators in patients with congenital heart disease. Patients and methods: A population-based case control study using data from general practices across the UK contributing data to the QRESEARCH primary care database. The subjects comprised 9952 patients with congenital heart disease and 29 837 matched controls. Outcome measures were prevalence of selected comorbidities; adjusted odds ratios for risk of comorbidities, healthcare utilisation and clinical indicator recording. Results: The overall crude prevalence of congenital heart disease was 3.05 per 1000 patients (95% CI 2.99 to 3.11). Prevalence of key comorbidities in patients with congenital heart disease ranged from 2.4% (95% CI 2.1% to 2.7%) for epilepsy to 9.3% (95% CI 8.8% to 9.9%) for hypertension. After adjusting for smoking and deprivation, cases were significantly more likely than controls to have each of the cardiovascular comorbidities and an increased risk of diabetes, epilepsy and renal disease. Patients with congenital heart disease were more frequent users of primary care than controls. Patients with congenital heart disease were also more likely than controls to have lifestyle and risk factor measurements recorded in primary care, although overall levels of recording were low. Conclusions: There is a significant burden of comorbidity associated with congenital heart disease, and levels of primary care utilisation and referral to secondary care are high in this patient group. The predicted future expansion in the numbers of adults with congenital heart disease owing to improvements in survival will have implications for primary and secondary care, and not just tertiary centres offering specialist care.