Association of Patient Characteristics with Risk of Rheumatic Heart Disease in First-Degree Relatives of Index Cases in Nepal

Rheumatic heart disease (RHD) is associated with significant morbidity and mortality, particularly in low- and middle-income countries. First-degree relatives (FDR) of RHD patients share known risk factors for RHD: poverty, poor living conditions, crowding, poor hygiene, and potential shared genetic characteristics that lead to higher RHD risk. We sought to determine whether FDR screening would be a high-yield method of screening patients for RHD to allow for timely preventive measures. This was a cross-sectional study based in two tertiary care centers in Nepal. RHD patients (n=102) were given the opportunity to invite their FDRs for RHD screening. A total of 234 FDRs without clinically recognized RHD participated in the RHD screening. Patients were screened using echocardiography by cardiologists at the two sites and RHD was adjudicated by a committee of cardiologists and echo-sonographers at the University of Washington according to the World Heart Federation classification of “definite” or “borderline” RHD. We assessed prevalence of RHD among FDRs and compared them with prior school-based screening results in Nepal. We examined whether index case characteristics (age, sex, socio-economic status (SES) and family history of having RHD) were associated with likelihoodof the index case having at least one FDR with borderline or definite RHD using multi-variable adjusted logistic regression. The mean ages of the 102 index RHD cases and of the 234 FDRs were 29.6 and 29.0 years, respectively. 74% of the RHD cases and 58% of the FDRs were women. Among the 234 FDRs, 19 (8.1%; 95% CI 5.1%-12.6%) had borderline or definite RHD of which 8 (3.4%; 95% CI 1.6%-6.9%) had definite RHD. Prior screening efforts in Nepal have been limited to examining children in schools and have yielded a prevalence of 0.1%-3.7% for borderline or definite RHD. Of the 102 index cases participating in this study, 17.6% had at least one FDR with borderline or definite RHD. Index case age, sex, SES, family history of having RHD were not associated with likelihood of having an FDR screen positive for RHD. Of the 52 child-parent relationships where the index case was the child, no parent had borderline or definite RHD. Of the 111 sibling-sibling relationships, 8 FDRs (12.5%) screened positive for borderline or definite RHD. Of the 71 parent-child relationships where the index case was the parent, 11 children (15.5%) screened positive for borderline or definite RHD. Our study demonstrates that screening FDRs of known RHD cases is a high-yield method of identifying previously unrecognized RHD. Identification of FDRs with RHD can encourage these patients to receive earlier treatment with penicillin prophylaxis to prevent further reinfection and valvular damage. Coupled with a penicillin prophylaxis program, adoption of FDR screening into the national RHD screening strategy in RHD-endemic countries like Nepal could improve RHD care worldwide.