Trends in CD4+ cell counts, viral load, treatment, testing history, and sociodemographic characteristics of newly diagnosed HIV patients in Osaka, Japan, from 2003 to 2017: a descriptive study.

BACKGROUND The CD4 cell count of patients during diagnosis and distribution of CD4 cell counts in the patient population are important to understand infection-diagnosis interval and incidence rate of human immunodeficiency virus (HIV) infection, respectively. However, this information has not been published in Japan. This study aimed to describe the change in CD4 cell count trend and clarify the change in patients' characteristics in association with the CD4 cell count information. METHODS A descriptive study was conducted to analyze the medical records of patients with HIV who visited one of the largest acquired immunodeficiency syndrome (AIDS) core hospitals in western Japan. The basic characteristics, CD4 cell counts, viral load, and diagnosis-treatment interval between the first (2003-2010) and second (2011-2017) halves of the study duration were compared. RESULTS The distribution of the CD4 cell counts significantly changed between 2003-2010 and 2011-2017 (χ2 = 20.42, p < 0.001). The proportion of CD4 cell count <200 cells/mm3 increased (38.8% in 2003 to 45.9% in 2017), whereas CD4 cell count ≥500 cells/mm3 decreased (19.4% in 2003 to 12.2% in 2017). Moreover, the distributions of age groups, history of HIV screening test, patient outcomes, HIV viral load, and diagnosis-treatment interval also significantly changed (χ2 = 25.55, p < 0.001; χ2 = 8.37, p = 0.015; χ2 = 6.07, p = 0.014; χ2 = 13.36, p = 0.020; χ2 = 173.76, p < 0.001, respectively). CONCLUSION This study demonstrated the fundamental trends of the HIV epidemic in Osaka, Japan, and indicated the incidence rate of HIV was decreasing in Japan.