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A high C-reactive protein level and poor performance status are associated with delayed sputum conversion in elderly
Kosaku Komiya1,2, Akihiko Goto1,2, Takamasa Kan1,2
1Internal Medicine, National Hospital Organization Nishi-Beppu Hospital, Beppu, Japan.
Introduction:
Although the aging population had been increasing in many countries, the factors associated with sputum conversion in elderly patients with pulmonary tuberculosis have not been fully elucidated.
Objectives:
We aimed to identify the predictors of delayed sputum conversion and to assess the impact of non-conversion on mortality during tuberculosis treatment in elderly patients.
Methods:
Elderly patients (>65 years) admitted at our hospital in Japan for sputum smear-positive pulmonary tuberculosis were included. The risk factors for sputum non-conversion after 2 months of treatment were determined using multiple logistic regression. Cox hazard regression was used to assess the influence of non-conversion on mortality.
Results:
We included 185 patients, with median age of 82 years (IQR, 79-88 years). The median time to conversion was 47 (95% CI 43-51) days, and 62 (34%) were identified as non-converters. Multivariate analysis showed that high pretreatment smear grade, high C-reactive protein level and poor performance status were associated with non-conversion. Non-conversion did not contribute to death during treatment.
Conclusions:
In elderly patients, inflammation level and physical activity level, along with initial smear grade may have a significant impact on delayed sputum conversion. Non-conversion after two months of treatment might not be related with mortality.
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