Risk Assessment Score and Chi-Square Automatic Interaction Detection Algorithm for Hypertension Among Africans: Models From the SIREN Study.

BACKGROUND: This study aimed to develop a risk-scoring model for hypertension among Africans. METHODS: In this study, 4413 stroke-free controls were used to develop the risk-scoring model for hypertension. Logistic regression models were applied to 13 risk factors. We randomly split the dataset into training and testing data at a ratio of 80:20. Constant and standardized weights were assigned to factors significantly associated with hypertension in the regression model to develop a probability risk score on a scale of 0 to 1 using a logistic regression model. The model accuracy was assessed to estimate the cutoff score for discriminating hypertensives. RESULTS: Mean age was 59.9±13.3 years, 56.0% were hypertensives, and 8 factors, including diabetes, age ≥65 years, higher waist circumference, (BMI) ≥30 kg/m2, lack of formal education, living in urban residence, family history of cardiovascular diseases, and dyslipidemia use were associated with hypertension. Cohen κ was maximal at ≥0.28, and a total probability risk score of ≥0.60 was adopted for both statistical weighting for risk quantification of hypertension in both datasets. The probability risk score presented a good performance-receiver operating characteristic: 64% (95% CI, 61.0-68.0), a sensitivity of 55.1%, specificity of 71.5%, positive predicted value of 70.9%, and negative predicted value of 55.8%, in the test dataset. Similarly, decision tree had a predictive accuracy of 67.7% (95% CI, 66.1-69.3) for the training set and 64.6% (95% CI, 61.0-68.0) for the testing dataset. CONCLUSIONS: The novel risk-scoring model discriminated hypertensives with good accuracy and will be helpful in the early identification of community-based Africans vulnerable to hypertension for its primary prevention.

Evaluation of the tuberculosis surveillance system in the Ashaiman municipality, in Ghana.

INTRODUCTION: Tuberculosis (TB) was the leading cause of death from an infectious illness globally with an estimated 10.4 million new cases and 1.4 million deaths in 2015. In Ghana, from the 2013 TB prevalence survey conducted by the National Tuberculosis Control Programme, the incidence is estimated as 165 per 100,000 population and a mortality rate of 7.5 per 1,000 infected people. The Tuberculosis surveillance system is part of the general framework of the Integrated Disease Surveillance and Response. This evaluation was to assess whether the system is meeting its set objectives, assess its usefulness and describe its attributes. METHODS: The TB surveillance system of the Ashaiman municipality was evaluated using Centre for Disease Control and Prevention updated guidelines for evaluating public health surveillance systems 2006. Records review from 2014 to 2016 was done to assess objectives of the system and surveillance data source of 2016 was used to assess attributes. Interviews were conducted at the various levels using semi-structured questionnaire and data analysis done with Epi info 7 and Microsoft Excel to run frequencies and percentages. RESULTS: The surveillance system is well structured with standardized data collection tools. The system was found to be useful, though it just partially met its objectives. It was also found to be simple, flexible and fairly stable with average timeliness. It had low acceptability and is not geographically representative. It had low sensitivity of 45/100,000 and a low predictive value positive of 6.6%. CONCLUSION: The surveillance system was found to be useful but partially met its objectives. There is the need to improve the sensitivity, predictive value positive timeliness and acceptability.

Risk factors for buruli ulcer in Ghana-a case control study in the Suhum-Kraboa-Coaltar and Akuapem South Districts of the eastern region.

BACKGROUND: Buruli ulcer (BU) is a skin disease caused by Mycobacterium ulcerans. Its exact mode of transmission is not known. Previous studies have identified demographic, socio-economic, health and hygiene as well as environment related risk factors. We investigated whether the same factors pertain in Suhum-Kraboa-Coaltar (SKC) and Akuapem South (AS) Districts in Ghana which previously were not endemic for BU. METHODS: We conducted a case control study. A case of BU was defined as any person aged 2 years or more who resided in study area (SKC or AS District) diagnosed according to the WHO clinical case definition for BU and matched with age- (+/-5 years), gender-, and community controls. A structured questionnaire on host, demographic, environmental, and behavioural factors was administered to participants. RESULTS: A total of 113 cases and 113 community controls were interviewed. Multivariate conditional logistic regression analysis identified presence of wetland in the neighborhood (OR=3.9, 95% CI=1.9-8.2), insect bites in water/mud (OR=5.7, 95% CI=2.5-13.1), use of adhesive when injured (OR=2.7, 95% CI=1.1-6.8), and washing in the Densu river (OR=2.3, 95% CI=1.1-4.96) as risk factors associated with BU. Rubbing an injured area with alcohol (OR=0.21, 95% CI=0.008-0.57) and wearing long sleeves for farming (OR=0.29, 95% CI=0.14-0.62) showed protection against BU. CONCLUSION: This study identified the presence of wetland, insect bites in water, use of adhesive when injured, and washing in the river as risk factors for BU; and covering limbs during farming as well as use of alcohol after insect bites as protective factors against BU in Ghana. Until paths of transmission are unraveled, control strategies in BU endemic areas should focus on these known risk factors.