Raluca Ionescu‐Ittu

BACKGROUND: Empirical data on the changing epidemiology of congenital heart disease (CHD) are scant. We determined the prevalence, age distribution, and proportion of adults and children with severe and other forms of CHD in the general population from 1985 to 2000. METHODS AND RESULTS: Where healthcare access is universal, we used administrative databases that systematically recorded all diagnoses and claims. Diagnostic codes conformed to the International Classification of Disease, ninth revision. Severe CHD was defined as tetralogy of Fallot, truncus arteriosus, transposition complexes, endocardial cushion defects, and univentricular heart. Prevalence of severe and other CHD lesions was determined in 1985, 1990, 1995, and 2000 using population numbers in Quebec. Children were subjects <18 years of age. The prevalence was 4.09 per 1000 adults in the year 2000 for all CHD and 0.38 per 1000 (9%) for those with severe lesions. Female subjects accounted for 57% of the adult CHD population. The median age of all patients with severe CHD was 11 years (interquartile range, 4 to 22 years) in 1985 and 17 years (interquartile range, 10 to 28 years) in 2000 (P<0.0001). The prevalence of severe CHD increased from 1985 to 2000, but the increase in adults was significantly higher than that observed in children. In the year 2000, 49% of those alive with severe CHD were adults. CONCLUSIONS: The prevalence in adults and median age of patients with severe CHD increased in the general population from 1985 to 2000. In 2000, there were nearly equal numbers of adults and children with severe CHD.

BACKGROUND: Our objective was to obtain contemporary lifetime estimates of congenital heart disease (CHD) prevalence using population-based data sources up to year 2010. METHODS AND RESULTS: The Quebec CHD database contains 28 years of longitudinal data on all individuals with CHD from 1983 to 2010. Severe CHD was defined as tetralogy of Fallot, truncus arteriosus, transposition complexes, endocardial cushion defects, and univentricular hearts. We used latent class bayesian models combining case definitions from physician claims, hospitalization, and surgical data to obtain point and interval prevalence estimates of CHD in the first year of life, in children (<18 years of age) and in adults. We identified 107 559 CHD patients from 1983 to 2010. Prevalence of CHD in the first year of life was 8.21 per 1000 live births (95% confidence interval, 7.47-9.02) from 1998 to 2005. In 2010, overall prevalence of CHD was 13.11 per 1000 (95% confidence interval, 12.43-13.81) in children and 6.12 per 1000 (95% confidence interval, 5.69-6.57) in adults. CHD prevalence increased by 11% in children and 57% in adults from 2000 to 2010. Prevalence in the severe CHD subgroup increased by 19% (95% confidence interval, 17%-21%) in children and 55% (51%-62%) in adults. By 2010, adults accounted for 66% of the entire CHD population. CONCLUSIONS: With an increase of >50% in CHD prevalence since 2000, by 2010 adults accounted for two thirds of patients with severe and other forms of CHD in the general population. Our findings should inform allocation of resources and the planning of workforce needs for the predominantly adult CHD population.

BACKGROUND: Atrial arrhythmias increase disease burden in the general adult population. Adults with congenital heart lesions constitute a rapidly growing group of patients with cardiovascular disease. We hypothesized that atrial arrhythmias increase with age and impair health outcomes in this population. METHODS AND RESULTS: We conducted a population-based analysis of prevalence, lifetime risk, mortality, and morbidity associated with atrial arrhythmias in adults with congenital heart disease from l983 to 2005. In 38 428 adults with congenital heart disease in 2005, 5812 had atrial arrhythmias. Overall, the 20-year risk of developing atrial arrhythmia was 7% in a 20-year-old subject and 38% in a 50-year-old subject. More than 50% of patients with severe congenital heart disease reaching age 18 years developed atrial arrhythmias by age 65 years. In patients with congenital heart disease, the hazard ratio of any adverse event in those with atrial arrhythmias compared with those without was 2.50 (95% confidence interval, 2.38 to 2.62; P<0.0001), with a near 50% increase in mortality (hazard ratio, 1.47; 95% confidence interval, 1.37 to 1.58; P<0.001), more than double the risk of morbidity (stroke or heart failure) (hazard ratio, 2.21; 95% confidence interval, 2.07 to 2.36; P<0.001), and 3 times the risk of cardiac interventions (hazard ratio, 3.00; 95% confidence interval, 2.81 to 3.20; P<0.001). CONCLUSIONS: Atrial arrhythmias occurred in 15% of adults with congenital heart disease. The lifetime incidence increased steadily with age and was associated with a doubling of the risk of adverse events. An increase in resource allocation should be anticipated to deal with this increasing burden.

BACKGROUND: Clinical guidelines recommend specialized care for adult congenital heart disease (ACHD) patients. In reality, few patients receive such dedicated care. We sought to examine the impact of specialized care on ACHD patient mortality. METHODS AND RESULTS: We examined referral rates to specialized ACHD centers and ACHD patient mortality rates between 1990 and 2005 in the population-based Quebec Congenital Heart Disease database (n=71 467). This period covers several years before and after the publication of guidelines endorsing specialized care for ACHD patients. A time-series design, based on Joinpoint and Poisson regression analyses, was used to assess the changes in annual referral and patient mortality rates. The association between specialized ACHD care and all-cause mortality was assessed in both case-control and cohort studies. The time-series analysis demonstrated a significant increase in referral rates to specialized ACHD centers in 1997 (rate ratio, +7.4%; 95% confidence interval [CI], +6.6% to +8.2%). In parallel, a significant reduction in expected ACHD patient mortality was observed after year 2000 (rate ratio, -5.0%;95% CI, -10.8% to -0.8%). In exploratory post hoc cohort and case-control analyses, specialized ACHD care was independently associated with reduced mortality (hazard ratio, 0.78; 95% CI, 0.65-0.94) and a reduced odds of death (adjusted odds ratio, 0.82; 95% CI, 0.08-0.97), respectively. This effect was predominantly driven by patients with severe congenital heart disease (hazard ratio, 0.38; 95% CI, 0.22-0.67). CONCLUSIONS: A significant increase in referrals to specialized ACHD centers followed the introduction of the clinical guidelines. Moreover, referral to specialized ACHD care was independently associated with a significant mortality reduction. Our findings support a model of specialized care for all ACHD patients.