Burden and clinical characteristics of high grade tuberculosis destroyed lung: a nationwide study.

Background: Little clinical information on high grade tuberculosis destroyed lung (TDL) is available. The aim of this study was to investigate the characteristics and healthcare utilization of high grade TDL patients, and compared the differences between acute exacerbation and healthcare burden according to inhaler compliance.

Methods: This was an observational retrospective cohort study using the Korean Health Insurance Review and Assessment (HIRA) service database (2011-2015). Patients diagnosed with high grade TDL in 2011 were enrolled and reviewed for 5 years. The patients were further divided into adherent and non-adherent groups. Their socioeconomic outcomes according to treatment adherence in 2012 were analyzed.

Results: Among the 13,346 patients diagnosed with high grade TDL, 3,637 were assigned to the adherent group and 9,709 to the non-adherent group. Overall, 65.91% of the enrolled patients were male and the mean age of the study population was 64.68±10.06 years. All patients visited a tertiary hospital, but 99.04% and 69.74% also visited primary and secondary hospitals, respectively. The mean number of hospital admissions per year was 1.38±2.03 times per patient. The average total annual per-patient cost was US$4,140.95±3,715.01 and each patient spent a total of 56.21±45.28 days per year using hospital services. The majority of the patients in the adherent group were male (80.09% . 60.60%, P<0.01), and were of older age (65.71±9.35 64.29±10.28, P<0.01) than the non-adherent group. The frequencies of visiting a tertiary hospital (96.87 . 90.12%, P<0.01), the total mean healthcare utilization costs (US$4,151.77±4,084.76 . US$3,592.54±4,229.93, P<0.01), and the frequencies of exacerbations (0.72±2.03 0.46±1.51, P<0.01) were higher in the adherent group. However, healthcare services were used on significantly fewer days in the adherent group (52.96±50.87 . 56.67±50.81, P<0.01).

Conclusions: High grade TDL imposes a high socioeconomic burden in Korea. Estimated medical costs and exacerbation event rate were higher in the adherent group whereas number of days of healthcare usage was significantly lower.