Echocardiography screening to detect rheumatic heart disease: A cohort study of schoolchildren in French Pacific Islands
Introduction
Rheumatic heart disease (RHD) is the result of valvular damage caused by an exaggerated immune response to group A streptococcal infections, usually during childhood and adolescence [1]. Although RHD, a disease of poverty, has almost disappeared from wealthy countries [2], its burden remains a major challenge in the developing world and among aboriginal populations in Pacific countries with approximately 345,000 deaths per year worldwide [3], [4], [5].
Rheumatic heart disease is still prevalent among Oceanic populations (Melanesians and Polynesians) in New Caledonia, a French overseas territory of 250,000 inhabitants. Unlike other countries, comprehensive programmes to tackle the burden of disease have proven inefficient so far in the region [6], [7], [8]. The World Health Organization has recommended active surveillance in order to initiate secondary prophylaxis early and prevent complications of the disease [9]. Echocardiography-based screening may present an attractive solution, ultrasounds being more sensitive to detect very mild valve lesions [10]. In this setting, the New Caledonians launched an echocardiography-based screening programme aiming at all primary schools (targeting 4th grade) from February 2008.
However, the natural history of echocardiography-detected RHD has never been established and the need for secondary prophylaxis still remains debated [11], [12]. There are therefore several unanswered questions in the field, as the outcomes of children screened for RHD, the need for secondary prophylaxis, and the target age-range. We address here the outcomes and modalities of screening through a cohort study of children with and without RHD who took part in the first large RHD echocardiography-based surveillance programme.
Section snippets
Study design and settings
In New Caledonia, active surveillance for RHD by means of ultrasounds was decided as a public health programme in 2007, and conduced in 17,633 schoolchildren in 4th grade (i.e., aged 9–10 years) between February 2008 and November 2011. All children diagnosed with RHD were offered free of charge secondary prophylaxis, yearly echocardiograms, and entered a national register. The aim of the study was to assess the outcomes of children detected by echocardiography as having RHD (RHD group), compared
Characteristics according to the initial diagnosis
One hundred and fourteen children with RHD diagnosed by echocardiography and 227 previously healthy children participated in the study (Fig. 1). Subjects' characteristics, according to groups, are depicted in Table 2. The mean age (SD) at the time of screening was 9.9 ± 0.7 in the RHD group, and 10.0 ± 0.7 in the normal baseline echocardiography group (non-RHD group), with a sex ratio (M/F) of 0.9 in the RHD group and of 1.0 in the non-RHD group. Among the 114 children with a positive screening for
Discussion
We assess here the largest cohort of children diagnosed with RHD by means of school-based echocardiography screening and compare them to matched schoolchildren with normal baseline echocardiography. We demonstrate that the majority of valve lesions, albeit mild, persist under secondary prophylaxis. Overcrowded living conditions were associated with the persistence of the disease. Oceanic children with normal baseline echocardiograms when aged 9–10 years yield considerable risk of developing ARF
Conclusion
Rheumatic heart disease diagnosed by echocardiography-based screening is often mild but nevertheless an irreversible condition in schoolchildren under secondary prophylaxis. Overcrowding appears to be the strongest predictor of the persistence of the disease. Serial assessment throughout childhood may be of interest. Further studies are warranted to assess the need for secondary prophylaxis in subclinical RHD.
Conflict of interest
The authors report no relationships that could be construed as a conflict of interest.
Acknowledgements
We are very grateful to Dr. Sylvie Laumond and Dr. Jean Paul Grangeon for their assistance regarding the National Mortality Database, and to Dr. Bertrand Huon and Dr. Pierre-Henri Ledos for their work in the surveillance programme.
Funding: Dr. Mirabel received funding from the Fondation pour la Recherche Médicale (Grant #2356) and the Fondation Lefoulon Delalande (Grant #15_2014).
References (32)
- et al.
Rheumatic heart disease
Lancet
(2012) - et al.
The global burden of group A streptococcal diseases
Lancet Infect. Dis.
(2005) - et al.
Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010
Lancet
(2012) - et al.
Prevention of rheumatic fever in Costa Rica
J. Pediatr.
(1992) - et al.
10-year educational programme aimed at rheumatic fever in two French Caribbean islands
Lancet
(1996) - et al.
Challenges of using ultrasounds for subclinical rheumatic heart disease screening
Int. J. Cardiol.
(2013) - et al.
Assessment of a register-based rheumatic heart disease secondary prevention program in an Australian Aboriginal community
Aust. N. Z. J. Public Health
(2005) - et al.
Active surveillance for rheumatic heart disease in endemic regions: a systematic review and meta-analysis of prevalence among children and adolescents
Lancet Glob. Health
(2014) - et al.
A prospective survey of patients with valvular heart disease in Europe: the Euro Heart Survey on Valvular Heart Disease
Eur. Heart J.
(2003) - et al.
Acute rheumatic fever: a population-based study in Wallis, a South Pacific island
Int. J. Cardiol.
(2014)