Globally, non-communicable diseases (NCDs) are the leading cause of death and disability with a particularly high burden in Low- and middle-income countries (LMICs), where more than 75% of all premature NCD deaths occur. Lesotho is a typical example of an African LMIC where NCDs are overtaking Human immunodeficiency virus (HIV)/AIDS and other infectious diseases as major cause of disability, morbidity and early death. HIV and NCDs are chronic diseases and share several characteristics such as the asymptomatic initial phase, progression to complications with disability and early death, and need for life-long treatment. The Ministry of Health (MoH) of Lesotho has therefore proposed in its NCD strategic plan that lessons learnt from the HIV program should be taken up to similarly reduce the existing access barriers to NCD care. Two scoping reviews have shown that the evidence on how and to what extent task shifting to lay workers can successfully be implemented for NCDs in sub-Sahara Africa is very limited. This open, prospective cohort study aims at generating evidence on community-based screening, diagnosis and management of uncomplicated arterial hypertension (aHT), Diabetes mellitus (DM) and other chronic diseases by lay Village health worker (VHWs) in a rural sub-Saharan African setting. It is to establish an observational cohort (ComBaCaL cohort) with regular monitoring of chronic disease indicators and risk factors in Butha-Buthe and Mokhothlong districts in Lesotho that will be managed by lay Chronic Care Village Health Workers (CC-VHWs), supported by a dedicated tablet-based eHealth application. The prevalence of common chronic diseases and associated risk factors in the cohort population and will be assessed and their development over time will be monitored. Initial focus will be on aHT, DM, cardiovascular disease risk factors (CVDRFs) and HIV. Other conditions may be included at a later stage. The effect of the ComBaCaL activities on condition- specific care cascade outcomes, such as screening coverage, disease awareness, linkage to care, engagement in care and disease control rates will be analyzed. Cohort variables will be assessed at baseline and pre-specified analyses to assess the effect of the ComBaCaL on chronic disease care cascades will be conducted at six months (range 150-240 days) and twelve months (range 300-480 days) after enrolment. Variables which may change over time will be reassessed during follow-up visits at intervals of around six months.
The ComBaCaL cohort will be a platform for nested pragmatic trials (Trials within a Cohort, TwiCs) assessing chronic disease care interventions.