Skip to main content

Table 2 Univariate and multinomial logistic regression analysis of demographic and clinical characteristics of hospitalised patients with invasive, non-invasive, and non-pneumococcal disease

From: Epidemiology, vaccine effectiveness, and risk factors for mortality for pneumococcal disease among hospitalised adults in Singapore: a case-control study

CharacteristicsIPD (N = 92), N(%)Non-IPD (N = 404), N(%)Non-pneumococcal disease (N = 9181), N(%)p value for trendRRR1 (95% CI) (IPD vs non-pneumococcal disease)p valueRRR2 (95% CI) (Non-IPD vs non-pneumococcal disease)p value
Age, mean (years) ± SD61.5 ± 16.370.8 ± 14.772.2 ± 16.1< 0.001    
Age group   < 0.001    
  < 65 years50 (54.4)120 (29.7)2449 (26.7) Ref Ref 
 65-74 years22 (23.9)103 (25.5)1885 (20.5) 0.65 (0.39–1.09)0.1011.17 (0.89–1.54)0.258
 75-84 years14 (15.2)117 (29.0)2719 (29.6) 0.31 (0.17–0.56)< 0.0010.96 (0.74–1.25)0.774
  ≥ 85 years6 (6.5)64 (15.8)2128 (23.2) 0.19 (0.09–0.44)< 0.0010.72 (0.52–0.98)0.038
Gender = male66 (71.7)259 (64.1)5035 (54.8)< 0.0011.87 (1.18–2.96)0.0081.42 (1.15–1.76)0.001
Ethnicity   0.202    
 Chinese63 (68.5)296 (73.3)6940 (75.6)     
 Malay11 (12.0)50 (12.4)852 (9.3)     
 Indian11 (12.0)28 (6.9)788 (8.6)     
 Others7 (7.6)30 (7.4)601 (6.6)     
Nursing home residence2 (2.2)2 (0.5)96 (1.1)0.247    
Vaccination status (received ≥ 14 days prior to admission)
 PCV131 (1.1)5 (1.2)105 (1.1)0.861    
 PPSV232 (2.2)76 (18.8)1632 (17.8)< 0.001    
 Any pneumococcal vaccination3 (3.3)77 (19.1)1695 (18.5)0.0010.20 (0.06–0.69)0.0111.05 (0.77–1.43)0.771
 Influenza vaccination6 (6.5)69 (17.1)1392 (15.2)0.0390.83 (0.34–2.02)0.6851.16 (0.84–1.60)0.371
Co-morbidities
 Charlson’s score, median (IQR)1 (0–4)2 (1–4)3 (1–5)< 0.001    
 Charlson’s score > 326 (28.3)111 (27.5)3753 (40.9)< 0.0010.72 (0.45–1.15)0.1700.55 (0.44–0.68)< 0.001
 Myocardial infarction / Congestive heart failure31 (33.7)112 (27.7)2718 (29.6)0.492    
 Cerebrovascular disease6 (6.5)60 (14.9)1737 (18.9)0.001    
 Dementia3 (3.3)51 (12.6)1529 (16.7)< 0.001    
 Chronic pulmonary disease14 (15.2)135 (33.4)2513 (27.4)0.001    
 Liver disease5 (5.4)22 (5.5)604 (6.6)0.667    
 Diabetes mellitus24 (26.1)123 (30.5)3548 (38.7)< 0.001    
 Renal disease19 (20.7)74 (18.3)2665 (29.0)< 0.001    
 Any malignancy11 (12.0)42 (10.4)1232 (13.4)0.201    
Outcomes
 ICU admission19 (20.7)35 (8.7)574 (6.3)< 0.001    
 Length of stay (days), median (IQR)9 (8–17)8 (5–14)8 (5–13)0.003    
 Length of stay > 7 days71 (77.2)204 (50.5)4918 (53.6)< 0.001    
 In-hospital mortality24 (26.1)46 (11.4)836 (9.1)< 0.001    
 30-day in-hospital mortality8 (8.7)25 (6.2)465 (5.1)0.096    
Readmission for any pneumococcal infection
 Anytime during study period0 (0.0)6 (1.5)16 (0.2)0.001    
 Within 30 days from discharge date0 (0.0)1 (0.25)2 (0.02)0.146    
  1. Variables included in the final multivariable analysis were age group, gender, any pneumococcal vaccination, influenza vaccination, and Charlson’s score > 3. IPD invasive pneumococcal disease, RRR adjusted relative risk ratio, CI confidence interval, SD standard deviation, PCV13 13-valent pneumococcal conjugate vaccination, PPSV23 23-valent pneumococcal polysaccharide vaccine, IQR inter-quartile range, ICU intensive care unit