Characteristics of mortality in HIV-negative cryptococcosis patients: Analysis of a cohort of 743 patients

Background Reports of cryptococcosis among patients without human immunodeficiency virus(HIV) infection are increasing. However, there is still a lack of data regarding the mortality characteristics in this population. Method The clinical, laboratory, imaging data from 743 HIV-negative patients with cryptococcosis were analyzed. Kaplan-Meier analysis was used to estimate all-cause mortality at 2-week, 10-week, and 1-year, with comparisons between groups using log-rank tests. Risk factor analysis was conducted using Cox models. Additionally, a meta-analysis was conducted on four recent large-scale cohort studies to investigate the differences in 2-week mortality of HIV-negative cryptococcosis across different regions. Statistical analyses were performed using R. Result The 2-week, 10-week, and 1-year mortality rates were 1.4% (95%confidence interval[CI], 0.5-2.2%), 8.4%(95%CI, 6.3-10.4%), and 12.2%(95%CI, 9.7-14.7%), respectively. Old age, higher baseline modified Rankin Scale scores, altered mental status, elevated total bilirubin levels, increased peripheral white blood cell counts, reduced serum albumin levels, elevated creatinine levels were associated with the mortality of cryptococcosis patients. For investigating the difference in 2-week mortality between Western and Chinese HIV-negative cryptococcosis, meta-analysis identified solid organ transplant and malignancy as risk factors (RR=1.50, 95% CI: 1.08-2.07, p=0.02), while meta-regression indicated that older age in HIV-negative patients in Western countries increased risk (RR=1.15, 95%CI: 1.09-1.22, p<0.001). Conclusion The mortality rate of HIV-negative cryptococcosis patients is relatively low and primarily occurs within 2 to 10 weeks. The characteristics contributing to a lower 2-week mortality rate differ significantly from those in the Western countries, mainly because of the differences in age and underlying risk populations.