Abstract:
Background: Rheumatic Heart Disease (RHD) is a preventable type of cardiovascular disease, most common among children and young, working adults, with twice the risk of developing RHD among females. There are over 15 million cases globally, with 282,000 new cases and 288,348 deaths annually, the majority being in low and middle-income countries. Africa experiences a more malignant course of RHD, with sub-Saharan Africa having a higher burden, reporting a loss of 10.7 million Daily Adjusted Life Years (DALYs). In Kenya, the Moi Teaching and Referral Hospital (MTRH) hosts the largest outpatient cardiac clinic in the Western region. Among its cardiac patients under the age of 50, Rheumatic Heart Disease (RHD) is the most common cardiovascular disease, affecting over 64% of these patients. Most of these patients are younger, with a mean of 26 years, 70% being female. The high number of patients with severe disease in MTRH means that they suffer a significantly higher economic burden compared to other patients with less severe disease.
Objectives: To determine the epidemiologic factors associated with the severity of RHD and assess various co-morbidities among RHD patients attending the Cardiology Clinic at MTRH.
Methods: A case-control study, with the definition of cases being patients with severe valvular disease or having mechanical prosthetic valves/valve repairs done, and controls being diagnosed with either moderate, mild or inactive RHD, both confirmed by echocardiography. A total of 110 participants were sampled, out of the 976 patients with RHD attending MTRH cardiac clinic. Data was collected using both face-to-face questionnaires and patient records. Dependent variables were either a case or control, and independent variables included socio-demographic data and epidemiologic characteristics associated with RHD. Continuous variables were analyzed using measures of central tendency and dispersion while categorical variables were analyzed using frequencies and proportions. Bivariate analysis was done using odds ratios (OR) at a confidence interval of 95%, and a p-value of ≤0.05 being considered a significant factor. Factors with a p-value of ≤ 0.2 were subjected to a multivariate analysis using unconditional logistic regression and significance was considered on factors with a p-value of ≤0.05.
Results: The mean age among the cases was 35 (SD±11.4), and 27 (SD±11.3) among the controls, with the female cases and controls being 72.5% and 68% respectively (OR=1.3; p=0.34). Most of the cases did not practice regular physical exercise (69%) (OR=2.3; p=0.0344), while 51% of the controls practiced regular physical exercise (OR= 0.43; p= 0.0215). The Body Mass Index (BMI) of overweight and obese ranges among the adult cases, were 43.7%, with 90% of them being females. The proportion of cases with a family history of chronic illness was 78.2% (OR=8.02; p=<0.0001), heart disease being the most common form of chronic illness in their family history. The participants’ socioeconomic status showed that 11.6% of the cases were unemployed, with only 2.4% of the controls being unemployed (OR= 6.61; p=0.05). The cases and controls with a previous history of alcohol intake were 20% and 1.8% respectively (OR=13.6; p=0.0144). Among the cases, 25% had comorbidities, while 12.7% of the controls had comorbidities (OR=2.342; p=0.0949). The most common comorbidities were stroke and hypertension, with over 50% having either of the two. Among the cases, participants with high blood pressure (systolic ≥140mmHg) were 16%, with 10% among the controls (OR= 1.6; p=0.04). Of the female participants who were on contraceptives, 23% of them were cases while 20% were controls (OR=1.24; p=0.04). Multivariate analysis revealed that occupation, alcohol use and lack of regular exercise remained significant with p-values of 0.000217, 0.000007, and 0.021, respectively.
Conclusion: Severe RHD is common in the younger population and females. Low socioeconomic status and harmful use of alcohol were major drivers in increasing progression to severity. Regular physical exercise was a protective factor in preventing severe RHD.
Recommendations: Patients attending the cardiac clinic at MTRH should receive education on the adverse effects of alcohol consumption, undergo regular hypertension screenings, and be encouraged to engage in consistent physical exercise. Additionally, educational initiatives and awareness campaigns should be conducted in schools and among populations with low socioeconomic status.