Decreasing incidence and determinants of bacterial pneumonia in people with HIV: The Swiss HIV Cohort Study. Journal of Infectious Diseases
Balakrishna et al. aimed to estimate the incidence rate of bacterial pneumonia in the Swiss HIV Cohort Study (SHCS) and to assess the risk factors associated with incidence of bacterial pneumonia.
The authors included 12’927 people with HIV (PWH) with follow-ups between 2008 and 2018. These patients had 985 bacterial pneumonia events during a follow-up of 100’779 person-years. Bacterial pneumonia incidence significantly decreased from 13.2 cases/1000 person-years in 2008 to 6.8 cases/1000 person-years in 2018. Older age, lower education level, intravenous drug use, smoking, lower CD4-cell count, higher HIV load, and prior pneumonia were significantly associated with higher bacterial pneumonia incidence. Notably, CD4 cell counts 350–499 cells/μL were significantly associated with an increased risk compared to CD4 ≥ 500 cells/μL (adjusted hazard ratio, 1.39; 95% confidence interval, 1.01–1.89).
In conclusion, decreasing incidence over the last decade can be explained by increased CD4-cell counts and viral suppression and decreased smoking frequency. Hence, improvements in the cascade of care of HIV and decrease in smoking may have mediated a substantial decrease in bacterial pneumonia incidence.