Non-invasive biomarkers of stress in mothers, fathers and infants in urban and rural Malawi: a feasibility study

It is known that health in early life is a key determinant of later life risk of a number of important diseases including high blood pressure, diabetes and heart disease. Changes in stress hormones are thought to be important underlying mechanism. Stress hormones can be collected in biological samples collected in non-invasive ways - such as in saliva, hair and breast milk.

However, this has only really been tested in high income settings and it is not known whether collection of these samples will be acceptable and feasible in Malawi. It is likely that there are local cultural and technical issues - for example, length of hair, views on collecting samples in infants, difficulty with collecting samples at home, challenges with storing samples at home.

Two large population studies have been funded to look at the relationships between health in early life and later life disease in Malawi. Malawian infants are growing up in one of the least developed countries in the world and are at high risk of infections in childhood and heart disease, diabetes and high blood pressure in young adulthood. There is a huge opportunity to link to these studies and conduct more detailed studies in smaller groups of participants to look at potential underlying mechanisms, such as changes in stress hormones.

Therefore in this funding application we wish to determine the feasibility and acceptability of collecting non-invasive biological samples for measurement of 'stress' hormones from mothers, their partners and their infants. We will ask 50 women and their partners, to collect samples of saliva at home from themselves and their infants. Our trained research staff will also seek permission to collect hair samples and we will ask women to provide breast milk samples.

We will find out whether it is feasible to do these collections, ask the participants and the research staff for their views about the sample collections, and look at the quality of the samples collected and whether the protocols need to be changed in any way.

The findings will pave the way for a future funding application for a nested study within the larger studies. This will add value to the existing studies through exploration of underlying biological mechanisms linking early life development with later life disease. The proposed seed-funding will also build local capacity and expertise in use of non-invasive biological samples, which we identify to be of wider relevance for other work in Malawi.