An analysis of TB epidemiology from a primary care perspective using the General Practice Research Database.
Doctoral thesis, UCL (University College London).
Background: TB is a growing public health problem. Most research focuses on secondary care. This, the largest study of TB in primary care to date, aims to investigate aspects of TB epidemiology by examining the role of primary care in case detection, management and outcomes. Methods: Using data from the General Practice Research Database a case-control and a self-controlled study were undertaken to investigate TB pre-diagnosis and a self-controlled and cohort study to describe and quantify TB morbidity and mortality post-diagnosis. Results: 3032 TB cases and 15,160 matched controls were analysed. The pre-TB studies showed that cases had higher consultation rates, consulted on multiple occasions often with recurrent respiratory infections and experienced a diagnostic delay of up-to-4months. Strengths of association between symptoms, respiratory diseases and TB were also noted. The case-control study also showed that male gender, smoking and chronic disease were independent risk factors for TB. Post-TB, patients who survived at least 18months had no increase in morbidity but TB led to a slight increase in all-cause mortality (adjusted HR:1.53) and a case fatality rate at one year of 6.5%. Mortality was highest in the first year post-diagnosis. Undiagnosed pulmonary TB, older age, male gender, malignancy and chronic disease were all associated with a worse prognosis. At 10 years, TB cases had a 70% chance of survival compared to 79% for patients’ without-TB. Conclusions: Diagnosing TB in primary care remains a challenge due to its variable and non-specific nature but a window of opportunity exists from 4months following first presentation. Combining knowledge of the strength of association between TB, its symptoms and respiratory diagnoses, TB risk factors and raising awareness of newer investigations and local referral processes could help GPs make an earlier diagnosis. This research indicates a need for improved patient and professional awareness of TB and emphasises the need for earlier diagnosis.
|Title:||An analysis of TB epidemiology from a primary care perspective using the General Practice Research Database|
|Open access status:||An open access version is available from UCL Discovery|
|UCL classification:||UCL > School of Life and Medical Sciences > Faculty of Population Health Sciences > Institute of Epidemiology and Health Care > Primary Care and Population Health|
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