A study of tuberculosis in an urban community with particular reference to sunlight exposure and Vitamin D status

• Main Author: Steel, S.
• Published: University College London (University of London) 2012
• Subjects: 610
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.565732

This thesis presents a mixed method study of urban Tuberculosis, with reference to both social and physical factors. The initial study reports the social context of Tuberculosis in Brent, London. 104 subjects participated in focus group discussions from community organisations. Knowledge, perception and barriers to Tuberculosis treatment were explored. Participants included refugee, homeless and immigrant groups. A thematic analysis revealed stigma, memory of home life, knowledge of disease and Tuberculosis as ‘divine punishment’ as significant social factors. The professional groups reported language, patient expectations and the fragmentation of services as barriers to successful treatment. A second study explored the relationship between sunlight exposure and Vitamin D status in Tuberculosis cases and contacts. UVR exposure was measured using Polysulphone film over 8 weeks in an urban setting. Median values for 25(OH)D in index cases were 23.5 nmol/l and 33.0 nmol/l in contacts cases, at the end of the study period. Sun exposure was not significantly related to 25(OH)D in index cases ( r=0.016, sig=0.961, p=0.05) and showed only a weak positive correlation in contacts ( r=0.233, sig=0.44, p=0.05). No seasonal variation was evident in either group. The requirement to wear a film badge prevented some subjects taking part as this was perceived to be stigmatising. This was an unexpected finding. Only 12 index cases and 13 contacts completed the study. Finally, ambient UVR levels were measured in London and these data compared well with measurements from a rural site, suggesting that the potential for sun exposure is similar in both rural and urban settings. The stigma of Tuberculosis hinders treatment success as well as engagement with clinical research. Language difficulties and fragmentation of services make access and treatment completion challenging and complex. The built environment and lifestyle factors may influence the opportunity to obtain sufficient sunlight for Vitamin D sufficiency in those with Tuberculosis. Whether lack of sunlight causes Vitamin D deficiency requires further study.