A comparison between time to clinical stability in community-acquired aspiration pneumonia and community-acquired pneumonia

Abstract

Antimicrobial therapy has been the main stay of therapy of community-acquired aspiration pneumonia (CAAP), but the duration of treatment has not been established. The objective of this study was to describe the time to reach clinical stability in patients with aspiration pneumonia compared to community-acquired pneumonia (CAP). A retrospective case control study at two university affiliated centers encompassing 329 consecutive patients admitted with CAAP and 329 consecutive patients with CAP was conducted between 2007 and 2011. While the median time to stability for patients with CAP was distributed around a median of 4 days, there was a bimodal distribution for time to clinical stability in patients with CAAP with dual peaks at days 2 and 5, respectively. CAAP patients who required more than 2 days to achieve clinical stability had a higher mortality rate compared to those with 2 days or less [odds ratio (OR) 5.95, 95% CI 2.85-12.4], and a longer hospital stay (6.6 ± 5.8 vs. 3.9 ± 1.2 days; p < 0.001). None of the CAAP patients who achieved clinical stability in 2 days or less was transferred to a higher level of care. In a multivariate analysis, time to clinical stability was found to be an independent predictor of outcome in patients with CAAP (OR 2.59, 95% CI 2.02-3.32). Normalization of vital signs in aspiration pneumonia follows a distinct pattern from that of patients with CAP. Time to achieve clinical stability may assist in identifying CAAP patients who are likely to require a shorter hospital stay and a shorter course of antimicrobial therapy.

Prognostic implications of aspiration pneumonia in patients with community acquired pneumonia: A systematic review with meta-analysis

“…Five studies (6,042 subjects) analyzed 30-day mortality2158606566. The mortality in patients with aspiration risk was significantly higher than that in non-aspiration pneumonia in four of five studies (Table 2).…”

“…We finally included 19 studies in this systematic review: a second analysis of a multicenter retrospective international database of patients with CAP using propensity score analysis57, a secondary analysis of a prospective observational study58, four prospective observational studies59606162, ten retrospective observational studies21636465666768697071, a combined a retrospective derivation cohort and a prospective validation cohort72, two other combined a retrospective and a prospective observational studies7374. These studies were published from the USA (n = 5), France (n = 4), Japan (n = 4), Spain (n = 3), United Kingdom (n = 1), Canada (n = 1) and Switzerland (n = 1).…”

“…These studies were published from the USA (n = 5), France (n = 4), Japan (n = 4), Spain (n = 3), United Kingdom (n = 1), Canada (n = 1) and Switzerland (n = 1). They were assessed quality based on the modified Hayden’s criteria: good (n = 3)575872, moderate (n = 11)2161626364666769717374 or poor (n = 5)5960656870. The percentage of subjects with aspiration pneumonia ranged from 1.5 to 50.4%.…”

“…The wide range reported for the prevalence rate of aspiration pneumonia was, no doubt, influenced by subject selection criteria, how “aspiration pneumonia” was clinically defined, and by the judgment of the clinicians involved in making the diagnosis. Outcomes of these studies were classified as follows: 30-day mortality (n = 5)2158606566, in-hospital mortality outside of the ICU (n = 7)57596364697071, ICU mortality (n = 4)67727374, 90-day mortality (n = 1)68, 1-year mortality (n = 2)5869, all cause readmission (n = 2)5866, recurrent pneumonia (n = 3)586163, and treatment failure (n = 1)62. Three of 19 studies evaluated multiple outcomes505863.…”

“…When the study was excluded, the relative risk increased to 4.15 (95% CI, 2.48–7.01; P < 0.00001; I 2  = 86%). While two studies indicated that aspiration risk significantly increased 30-day mortality2165, the other studies did not retain statistical significance after adjustment586066. CURB-65 score (HR 1.495; 95% CI 1.033–2.163)21, moderate or severe liver disease (9.21; 3.16–26.86) and leukocytosis (4.47; 2.27–8.82) were additional risk factors for 30-day mortality65.…”