Table 1. Baseline demographic and clinical characteristics of the hospitalized Covid-19 patients stratified by age.
Characteristic All Patients <65 y ≥65 y p
(n=362) (n=258) (n=104)
(100%) (71.3%) (28.7%)
Age 56 (46-67) 50 (42-57) 73 (68-81) <0.001*
Sex 0.74
Male 224 (61.9%) 161 (62.4%) 63 (60.6%)
Female 138 (38.1%) 97 (37.6%) 41 (39.4%)
International travel history 6 (1.7%) 5 (1.9%) 1 (1%) 0.67
Contact history 134 (37%) 104 (40.3%) 30 (28.8%) 0.04*
Smoker 36 (9.9%) 34 (13.2%) 2 (1.9%) 0.001*
Alcohol 2 (0.6%) none 2 (1.9%) 0.08
Co-morbidities
Any 210 (58%) 126 (48.8%) 84 (80.8%) <0.001*
Hypertension 138 (38.1%) 73 (28.3%) 65 (62.5%) <0.001* Diabetes mellitus 85 (23.5%) 51 (19.8%) 34 (32.7%) 0.009*
COPD/asthma 41 (11.3%) 25 (9.7%) 16 (15.4%) 0.12
Coronary heart disease 37 (10.2%) 11 (4.3%) 26 (25%) <0.001*
Congestive heart failure 19 (5.2%) 3 (1.2%) 16 (15.4%) <0.001* Cerebrovascular disease 7 (1.9%) 3 (1.2%) 4 (3.8%) 0.10
Chronic renal failure 8 (2.2%) 5 (1.9%) 3 (2.9%) 0.69
Liver disease 4 (1.1%) 1 (0.4%) 3 (2.9%) 0.07
Malignancy 27 (7.5%) 12 (4.7%) 15 (14.4%) 0.001* Immunosupression 18 (5%) 13 (5%) 5 (4.8%) 0.92
Number of co-morbidities 1 (0-2) 0 (0-1) 2 (1-2.7) <0.001*
Symptoms
Fever 265 (73.2%) 199 (77.1%) 66 (63.5%) 0.008*
Cough 304 (84%) 227 (88%) 77 (74%) 0.001*
Dry cough 294 (81.2%) 219 (84.9%) 75 (72.1%) 0.005*
Dyspnea 158 (43.6%) 106 (41.1%) 52 (50%) 0.12
Fatigue/myalgia 328 (90.6%) 235 (91.1%) 93 (89.4%) 0.62
Sputum production 10 (2.8%) 8 (3.1%) 2 (1.9%) 0.73
Nausea (n=340) 59 (17.4%) 47 (18.2%) 12 (12.9%) 0.18
Diarrhea (n=340) 47 (13.8%) 36 (14%) 11 (11.8%) 0.51
Loss of smell/taste (n=340) 26 (7.6%) 23 (9.3%) 3 (3.2%) 0.068
Signs
Body temperature (ºC) 37.2 (36.5-38.2) 37.2 (36.5-38.2) 37.3 (36.5-38.2) 0.80
Fever (>38.3ºC) 71 (19.6%) 53 (20.5%) 18 (17.3%) 0.48
Subfebrile temperature (37.8-38.3ºC) 49 (13.5%) 28 (10.9%) 21 (20.2%) 0.02*
Dyspnea (use of accessory muscles) 113 (31.2%) 62 (24%) 51 (49%) <0.001*
Respiration rate (/min) 18 (16-23) 18 (16-22) 20 (18-26) <0.001*
Respiration rate
≥30/ min 25 (6.9%) 11 (4.3%) 14 (13.5%) 0.002*
SaO2 (%) 96 (93-97) 96 (94-98) 94 (89-96) <0.001*
SaO2<90% 13 (13%) 21 (8.1%) 26 (25%) <0.001*
Pulse rate (/min) 94 (86-105) 94 (88-105) 95 (84.2-102) 0.30
Need for oxygen support (SaO2< 93%) 74 (20.4%) 38 (14.7%) 36 (34.6%) <0.001*
Clinically severe pneumonia 114 (31.5%) 63 (24.4%) 51 (49%) <0.001*
Time from first symptom to hospitalization (d) 5 (3-7) 5 (3-7) 5 (3-7) 0.42
Data are given as median (interquartile range) for the continuous variables and as counts (%) for the categorical variables. COPD: chronic obstructive pulmonary disease, d: days, min: minute, SaO2: oxygen saturation *statistically significant
Table 2. Laboratory and radiological findings of the hospitalized Covid-19 patients at hospital admission stratified by age.
Characteristic All Patients <65 y ≥65 y p
(n=362) (n=258) (n=104)
(100%) (71.3%) (28.7%)
White blood cell count, ×109/L† 6.1 (4.8-7.7) 6.1 (4.8-7.5) 6.0 (4.6-8.4) 0.62
< 4 ×109/L 40 (11.0%) 31 (12%) 9 (8.7%) 0.35
>10 ×109/L 47 (13%) 30 (11.6%) 17 (16.3%) 0.22
Neutrophil count, ×109/L† 4.1 (3.2-5.8) 4.1 (3.2-5.5) 4.3 (3.2-6.4) 0.17
> 7.7 ×109/L 104 (28.7%) 31 (12%) 22 (21.2%) 0.02*
Lymphocyte count, ×109/L† 1.1 (0.8-1.5) 1.2 (0.9-1.6) 0.9 (0.7-1.4) <0.001*
<1 ×109/L 145 (40.1%) 85 (32.9%) 60 (57.7%) <0.001*
Hemoglobin (g/L) 132 (120-143) 134 (124-145) 125 (114-138) 0.001*
Platelet count, ×109/L† 204.5 (159.1-267.9) 197 (158-252.2) 215 (162.7-297.5) 0.2
<150 ×109/L 64 (17.7%) 45 (17.4%) 19 (18.3%) 0.85
<100 ×109/L 13 (3.6%) 9 (3.5%) 4 (3.8%) 1
ALT (U/L)† 24 (15-37.2) 27.5 (18-40.2) 19 (12-28) <0.001*
ALT> 45 U/l 60 (16.6%) 50 (19.4%) 10 (9.6%) 0.02*
AST (U/L)† 29 (21-43) 29 (22-42) 28.5 (19-49) 0.70
AST> 42 U/l 91 (25.1%) 64 (24.8%) 27 (26%) 0.81
Creatinine (umol/L)† 90 (70-110) 90 (70-100) 90 (77-120) 0.11
>104 umol/L 100 (27.6%) 61 (23.6%) 39 (37.5%) 0.008*
LDH (U/L)† 256 (206-332) 256 (204-320) 253 208-363) 0.93
LDH> 250 U/l 195 (53.9%) 141 (54.7%) 54 (51.9%) 0.63
Albumin (g/L)† 40 (36-44) 42 (38-44) 37 (33-41) <0.001*
<35 g/L 60 (16.6%) 27 (10.5%) 33 (31.7%) <0.001*
CRP (mg/L) 47 (18.7-91) 43.5 (16.7-79) 61 (34-154) <0.001*
CRP> 5 mg/L† 343(94.8%) 245 (95%) 98 (94.2%) 0.77
CRP> 40 mg/L‡ 206 (56.9%) 137 (53.1%) 69 (66.3%) 0.02*
Ferritin (ng/mL) 336 (163.7-707) 316 (164-638) 427 (159-798) 0.17
Ferritin> 500 ng/mL‡ 126 (34.4%) 83 (32.2%) 43 (41.3%) 0.09
D-dimer (ug/L) 750 (480-1312.5) 655 (430-1000) 1245 (740-2615) <0.001*
D-dimer >550 ug/l† 252 (69.6%) 162 (62.8%) 90 (86.5%) <0.001*
D-dimer> 1000 ug/l‡ 125 (34.5%) 63 (24.4%) 62 (59.6%) <0.001*
TnT (pg/ml) 6 (3-13) 4 (3-8) 17.5 (8-31.7) <0.001*
TnT >14 pg/ml† 81 (22.4%) 25 (9.7%) 56 (53.8%) <0.001*
Pro-BNP (pg/ml) 84 (28-348) 54.5 (23-134) 566 (137-1796) <0.001*
ProBNP >125 pg/ml † 146 (40.3%) 66 (25.6%) 80 (76.9%) <0.001*
Procalcitonin (ng/mL) 0.08 (0.05-0.16) 0.07 (0.05-0.14) 0.12 (0.06-0.26) <0.001
Procalcitonin> 0.5 ng/ml† 27 (7.5%) 13 (5%) 14 (13.5%) 0.006*
CT Findings (n= 355) (abnormal CT results) 0.006*
Mild pneumonia 161 (45.4%) 126 (50%) 35 (34%)
Moderate-severe pneumonia 194 (54.6%) 126 (50%) 68 (66%)
Data are given as median (interquartile range) for the continuous variables and as counts (%) for the categorical variables.
The cut-offs of the laboratory parameters were designated by † the local laboratory thresholds and ‡ the suggestion of diagnostic and treatment guidelines for SARS-CoV-2 issued by the Turkish National Scientific Committee directed by the Turkish Ministry of Health (17).
Admission laboratory studies were selected to be included here based on their relevance to the characterization of Covid-19 patients (5).
CT: computerized tomography, ProBNP: N-terminal pro-brain natriuretic peptide, TnT: high sensitive troponin T
*statistically significant
Table 3. Outcome and follow-up characteristics of the hospitalized Covid-19 patients stratified by age.
Characteristic All Patients <65 y ≥65 y p
(n=362) (n=258) (n=104)
(100%) (71.3%) (28.7%)
Outcome measures
Admission to ICU 53 (14.6%) 23 (8.9%) 30 (28.8%) <0.001*
Exitus 35 (9.7%) 11 (4.3%) 24 (23.1%) <0.001*
The time between (days)
hospitalization to ICU admission 2 (0.5-6) 2 (0-8) 2 (1-5.2) 1
(n=53) (n=23) (n=30)
Length of hospital stay (days) (n=362) 8.5 (6-13) 8 (6-12) 10 (6-18) 0.01*
ICU duration (days) (n=53) 26 (10.5-46.5) 15 (7-35) 36.5 (14.2-48.2) 0.06
(n=53) (n=23) (n=30)
Data are given as median (interquartile range) for the continuous variables and as counts (%) for the categorical variables
ICU: intensive care unit
*statistically significant
Table 4. Logistic regression analyses for factors associated with death in older adults (Backward LR method).
Characteristic Odds Ratio 95% Confidence Interval p
Clinically severe pneumonia on admission 12.3 (2.7-55.5) 0.001*
Increased ALT (>45 U/L) 2.3 (0.5-10.7) 0.27
Increased D-dimer (>550 ug/L) 0 0 0.99
Serum creatinine (mg/dL) 1.7 0.97-3.0 0.06
Dependent variable: death
Independent variables: presence of cough, clinically severe pneumonia on admission, presence of CRP> 40 mg/L, higher d-dimer, high sensitive troponin T, N-terminal pro-brain natriuretic peptide, LDH, ALT, and lower albumin levels by laboratory thresholds, serum creatinine and presence of moderate-severe pneumonia on computerized tomography.
(R2= 0.961 (Hosmer and Lemeshov test), Model x2 (8)=2.5; p<0.001)
*statistically significant difference