Table 2.
Characteristics of Patients With RT-PCR-Confirmed RSV Illness Stratified by Presence or Absence of RSV-msLRTD, Defined by at Least 3 of the Following Symptoms/Signs During the Initial Clinical Encounter: Cough, Wheezing (or Worsening in Baseline Wheezing), New Sputum Production (or Increase in Baseline Sputum), New (or Worsening) Shortness of Breath, and Observed Tachypnea (≥20 Breaths/Minute)
| Total RSV-Positive (n = 243), No. (%) | RSV-msLRTD | |||
|---|---|---|---|---|
| No (n = 184), No. (%) | Yes (n = 59), No. (%) | P d | ||
| Age group, y | .3 | |||
| 60–64 | 55 (23) | 38 (21) | 17 (29) | |
| 65–74 | 101 (42) | 78 (44) | 23 (35) | |
| 75+ | 87 (36) | 62 (35) | 25 (38) | |
| Gender | .009 | |||
| Male | 85 (35) | 56 (30) | 29 (49) | |
| Female | 158 (65) | 128 (70) | 30 (51) | |
| High-risk comorbid conditionsa | ||||
| COPD | 33 (14) | 18 (10) | 15 (25) | .002 |
| CHF | 22 (9) | 11 (6) | 11 (19) | .003 |
| Asthma | 48 (20) | 33 (18) | 15 (25) | .2 |
| Immune-compromised | 15 (6) | 7 (4) | 8 (14) | .01 |
| Diabetes | 51 (21) | 32 (17) | 19 (32) | .02 |
| Smoking status | .9 | |||
| Current smoker | 10 (4) | 7 (4) | 3 (5) | |
| Current nonsmoker | 228 (94) | 173 (94) | 55 (93) | |
| Unknown | 5 (2) | 4 (2) | 1 (2) | |
| Enrollment visita | ||||
| Symptoms during enrollment visit | ||||
| Self-reported fever | 84 (35) | 53 (29) | 31 (53) | .0008 |
| Cough, productive | 117 (48) | 66 (36) | 51 (86) | |
| Cough, nonproductive | 109 (45) | 101 (55) | 8 (14) | |
| New/increased sputum | 120 (49) | 69 (38) | 51 (86) | |
| New/increased dyspnea (SOB) | 47 (19) | 6 (3) | 41 (69) | |
| Hemoptysis | 3 (1) | 3 (2) | 0 (0) | 1.0 |
| Chest pain | 18 (7) | 10 (5) | 8 (14) | .04 |
| Myalgia | 45 (19) | 32 (17) | 13 (22) | .4 |
| Wheezing | 39 (16) | 9 (5) | 30 (51) | <.0001 |
| Sore throat | 152 (63) | 113 (61) | 39 (66) | .5 |
| Exam during enrollment visit | ||||
| Fever ≥100°F | 20 (8) | 12 (7) | 8 (14) | .09 |
| Wheezing | 49 (20) | 15 (8) | 34 (58) | |
| Respiratory distress | 6 (2) | 1 (1) | 5 (8) | .0006 |
| Tachypnea | 16 (7) | 1 (1) | 15 (25) | |
| Decreased breath sounds | 19 (8) | 6 (3) | 13 (22) | <.0001 |
| Crackles/rales | 23 (9) | 8 (4) | 15 (25) | <.0001 |
| Rhonchi | 31 (13) | 18 (10) | 13 (22) | .01 |
| Outcomes | ||||
| Hospital admissionb | 29 (12) | 12 (7) | 17 (29) | <.0001 |
| ED visit | 13 (5) | 9 (5) | 4 (7) | .5 |
| X-ray-confirmed pneumonia | 23 (9) | 8 (4) | 15 (25) | <.0001 |
| No. of outpatient provider–attended medical encounters for acute illness within 28 d, median (IQR)c | 1 (1–2) | 1 (1–2) | 2 (1–3) | .05 |
| Evaluations in the 28 d postenrollment | ||||
| Chest x-ray performed on date of enrollment visit | 94 (39) | 50 (27) | 44 (75) | <.0001 |
| Chest x-ray performed within 28 d | 118 (49) | 71 (39) | 47 (77) | <.0001 |
| O2 saturation measured within 28 d | 112 (46) | 69 (38) | 43 (73) | <.0001 |
| <90% O2 saturation | 11 (10) | 2 (3) | 9 (21) | .002 |
| Procalcitonin measured within 28 d | 7 (3) | 2 (1) | 5 (8) | .01 |
| Abnormal high | 3 (43) | 0 (0) | 3 (60) | .4 |
| Hemoglobin measured within 28 d | 63 (26) | 34 (18) | 29 (49) | <.0001 |
| Abnormal low | 12 (19) | 6 (18) | 6 (21) | .8 |
| Abnormal high | 1 (2) | 0 (0) | 1 (3) | .5 |
| Creatinine measured within 28 d | 76 (31) | 47 (26) | 29 (49) | .0007 |
| Abnormal high | 19 (25) | 13 (28) | 6 (21) | .5 |
| Leukocyte count measured within 28 d | 62 (26) | 33 (18) | 29 (49) | <.0001 |
| Leukopenia | 1 (2) | 1 (3) | 0 (0) | 1.0 |
| Leukocytosis | 7 (11) | 4 (12) | 3 (10) | .8 |
| Therapeutic interventions in the 28 d postenrollmenta | ||||
| Oxygen administered | 36 (15) | 17 (9) | 19 (32) | <.0001 |
| New bronchodilator/nebulizer treatment | 71 (29) | 37 (20) | 34 (58) | <.0001 |
| New/increased corticosteroid Rx | 44 (18) | 20 (11) | 24 (41) | <.0001 |
| New antibiotic prescription | 187 (77) | 135 (73) | 52 (88) | .02 |
| Antiviral prescription | 9 (4) | 8 (4) | 1 (2) | .7 |
Abbreviations: CHF, congestive heart failure; COPD, chronic obstructive pulmonary disease; ED, emergency department; IQR, interquartile range; msLRTD, moderate to severe lower respiratory tract disease; RSV, respiratory syncytial virus; RT-PCR, reverse transcription polymerase chain reaction; SOB, shortness of breath.
aHigh-risk comorbid conditions (except immune-compromised status, which was determined from electronic diagnosis codes), symptoms/exam findings from enrollment visit, and therapeutic interventions were obtained by medical record abstraction.
bThree additional hospital admissions occurred within 28 days for incarcerated hernia, small bowel obstruction, and acute gastrointestinal illness. These conditions were considered unrelated to the preceding RSV infection.
cWilcoxon test was used for differences in medians.
d P-values not shown for characteristics which contributed to the msLRTD case definition.