*Update* This project was undertaken by Dr Mark Cherrie and is now complete, you can read more about part of the published work here.

This European Social Fund supported PhD project will build upon previous work associating latitude, a proxy for sunlight and vitamin D synthesis, and atopic diseases by exploring if there is a link between solar irradiance and increased prevalence of eczema.

Eczema is a prevalent disease with higher incidence in younger people in the UK; in 1996 it was calculated that 24% of children (2-15 years old) have had at least one eczema diagnosis. Eczema is thought to be caused by interplay between genetic predisposition and environmental risk factors.

Recently, vitamin D deficiency has been linked to the risk of being diagnosed with eczema and the development of asthma later in life. Vitamin D can be ingested through food or manufactured in the skin via sunlight.

Studying low solar irradiance instead of solely latitude will take account of cloud cover and irradiance at key times of the year (i.e. late Autumn), which can affect sunlight and therefore vitamin D synthesis while taking into account other risk factors and potential confounders, such as birth month, age, sex, diet, ethnicity, SES etc.

Data from the Met Office/HPA (satellite origin UV irradiance), the MRC/NHS (extant epidemiological studies) and other large health studies will be gathered and collated. Factors to be explored include the amount of time spent indoors/outdoors, differing levels of exposure and will be explored using multivariate logistic regression.

Future work can use the association between exposure to sunlight and the risk of developing eczema as a model for examining other atopic diseases.

This project is working closely with experts at the Met Office.