Nationwide Trends in Hospitalization, In-Hospital Case Fatality, and Hospital Reimbursement for Skin and Soft-Tissue Infections in Brazil, 2000-2023: An Ecological Time-Series Analysis

IntroductionSkin and soft-tissue infections (SSTIs), including cellulitis, cutaneous abscess, and erysipelas, are a common cause of hospitalization, yet nationwide evidence on their long-term hospital burden in Brazil is limited. Methods This is a nationwide ecological time-series study of hospital admissions with a principal diagnosis of International Classification of Diseases, 10th revision (ICD-10) L00-L08 or A46 recorded in the Sistema de Informações Hospitalares do Sistema Único de Saúde (Hospital Information System of the Brazilian UnifiedHealth System) (SIH/SUS), which covers admissions financed by the public health system, Brazil and its five macro-regions, 2000-2023.Hospitalization rates were standardized by age and sex to the 2022 Census population, and in-hospital case fatality by age and sex to the distribution of all admissions.Trends were estimated as annual percent changes (APC) by Prais-Winsten regression within two pre-specified subperiods separated by the introduction of the unified SUS procedure table in January 2008 (2000-2007; 2009-2019, excluding the pandemic), which were the principal estimates, and over the full period as a summary of net change, with segmented regression as a supplementary analysis.Reimbursement (2008-2023) was deflated to 2023 Brazilian reais (R$). ResultsThere were 2,508,028 hospitalizations and 36,909 in-hospital deaths (case fatality 36,909/2,508,028, 1.47%).The age-and sex-standardized rate was 46.4 per 100,000 in 2000, dropping to 35.6 in 2008, the first year of the unified table, rising to 77.7 in 2019, falling by 24.6% in 2020 (157,709 to 120,143 admissions), and reaching 75.6 per 100,000 in 2023.The rate rose in 2009-2019 (APC +4.41% per year, 95% CI 3.42 to 5.41), with no significant trend observed between 2000 and 2007; the net average change over 2000-2023 was +2.64% per year (95% CI 1.54 to 3.75).The full-period rise was significant in the North, Northeast, Southeast, and South but not the Central-West.Crude case fatality rose from 0.74% (536 of 72,760) in 2000 to 1.78% (2,834 of 159,543) in 2023 (APC +3.53% per year, 95% CI 2.42 to 4.66); standardized for age and sex, it rose from 0.97% to 1.53% (APC +1.68% per year, 95% CI 0.72 to 2.65), and about half of the crude increase reflected the older age of admitted patients.Rates were higher in men, and the male-to-female ratio of rates standardized to a common age distribution widened from 1.21 to 1.46.Mean inflation-adjusted reimbursement per hospitalization fell from a 2010 peak of R$978 to R$685 in 2023 (APC -1.89% per year, 95% CI -2.92 to -0.85). ConclusionsThe recorded age-and sex-standardized rate of SUS-financed hospitalization for SSTIs and erysipelas in Brazil was nearly two-thirds higher in 2023 than in 2000, a descriptive comparison of two years; the rise was concentrated in 2009-2019 and varied between regions.In-hospital case fatality rose, about half of it because admitted patients became older, and inflation-adjusted reimbursement per admission declined.Because 2008 was a transition-year trough coinciding with the implementation of the unified procedure table, trend estimates from Brazilian hospital data that start in that year overstate the increase.