Background: Investigation of tuberculosis (TB)-specific indices including prevalence of TB, mortality of TB cases excluding HIV, HIV/TB mortality, incidence of TB (all forms), HIV/TB incidence as well as case detection and related trends is a crucial step in evaluation of program performance and strategies success. Besides, estimating the number and time of change points for TB incidence can help to detect effective factors in TB control. Therefore, the current study aimed to determine the trend of aforementioned indices in Iran during a 25 yr period (1990 to 2014).
Methods: Data on trend of TB in Iran was extracted from WHO regional office reports during 1990-2014. For determining the trend of TB indices, Annual Percent Changes (APC) and Average Annual Percent Changes (AAPC) was estimated using segmented regression model.
Results: AAPC (95% CI) for HIV/TB mortality and HIV/TB incidence were 11.5 (9.3, 13.6) and 14.8 (13.6, 16.1), respectively, which are sign of increasing trend during the period (P<0.05). Other indices showed significantly decreasing trend (P<0.05), except for case detection rate (P =0.803).
Conclusions: The incidence, prevalence, and death rates of TB had shown a decreasing trend in general population, regarded as a useful indicator of achievements of Millennium Development Goals (MDGs) and effectiveness of interventional programs. Increasing trend of incidence and mortality of TB in HIV infected patients, needs conducting more intervention strategies in health care programs.
Keywords: Annual Percent Change; Iran; Segmented regression; Tuberculosis.