Assessing multimorbidity of non-communicable diseases and schistosomiasis in rural Uganda

BACKGROUND

An estimated 250 million people worldwide have schistosome infections, of which 90% are in sub-Saharan Africa. Blood flukes (parasitic worms) cause schistosomiasis—a set of conditions associated with acute and chronic infections. Chronic Schistosoma mansoni infections can cause liver fibrosis, diarrhoea, gastrointestinal haemorrhage, anaemia, malnutrition, and portal hypertension as well as other impairments such as reduced cognitive development, educational attainment, and work productivity.

Due to the long lifespan of the parasite, lack of protective treatment against reinfection, and complex social-ecological risk factors, multiple concurrent conditions are on the rise in areas endemic with schistosomiasis. For example, alcoholism is common among high-risk groups for schistosomiasis such as fishermen (est. >40%). Yet, there are no models for the risk factors shared between NCDs and schistosomiasis that contribute to multimorbidities, i.e., two or more chronic conditions and/or infections. Multiple conditions often interact, have similar aetiologies, share treatment strategies, or have shared socioeconomic determinants (despite distinct biological causes).

RESEARCH EXPERIENCE, RESEARCH METHODS AND TRAINING 

This project will use data from an ongoing cohort study (SchistoTrack/EpiMM-Schisto) in rural villages in Uganda where S. mansoni is endemic. Ethical approvals have been obtained. The baseline and first annual follow-up will be collected prior to the start of this DPhil project. Three more years of follow-up will occur during the timeframe of this DPhil. This analysis will focus on a random sample of approximately 1800 households from 45 villages. One child (aged 5+ years) and one adult (aged 18+ years) will be sampled from each study household (~3600 individuals). Infection is measured with point-of-care diagnostics and microscopy. Household surveys are used to collect information on non-communicable diseases (using the WHO STEPS survey) including but not limited to alcohol consumption, smoking behaviours, and history of diabetes and stroke.

Clinical assessments of arterial hypertension and anthropometry, including indicators of adiposity also are available. Detailed information will be available on demographics, socioeconomic status, and water, sanitation, and hygiene access/behaviours.

Aims:

1. Identify the key risk factors for individual NCDs in the study population.
2. Assess how NCD prevalence varies by schistosome prevalence and intensity, contributing to established schistosomiasis models from the group.
3. Identify common clusters of NCDs with schistosomiasis and key risk factors/shared pathways in the co-distribution of common NCDs (e.g. alcoholism and smoking) using DAGs, Bayesian networks, etc.
4. Examine the variation in NCD and schistosomiasis co-occurrence either over a lifespan by assessing the variation against age in a cross-sectional study or longitudinally from year-to-year in the cohort.

There is scope to tailor the project, especially the NCD focus areas, to the student’s interest. The student will gain skills in literature review, primary data collection, clinical epidemiological data analysis, statistical programming, data cleaning, and research presentation.

FIELD WORK, SECONDMENTS, INDUSTRY PLACEMENTS AND TRAINING

This DPhil project requires 1-2 months of fieldwork in rural Uganda. Experienced field teams from the Uganda Ministry of Health will co-lead the primary data collection with the primary supervisor.

PROSPECTIVE STUDENT

The ideal candidate will have a Master’s degree in statistics/epidemiology/public health or a related quantitative discipline in computer science, mathematics, engineering, or economics.