Out of a total of 68,983 people (80.34% of the primary data) subjected to the final analysis, 32,534 people (47.2%) were men, and 36,449 people (52.8%) were women. The mean (SD) age of these hospitalized patients was 49 (23.98) years (Table 1).
Table 1
Baseline charachteristics and death rate of COVID-19 hospitalized patients in Golestan province, Iran.
| | Outcome | |
Variables | Classification | Death | Discharge | Total |
Frequency (%) | Frequency (%) | Number |
Age (years) | 0–17 | 259 (2.9) | 8684 (97.1) | 8943 |
18–29 | 132 (3) | 4257 (97) | 4389 |
30–39 | 316 (3.9) | 7736 (96.1) | 8052 |
40–49 | 657 (7.3) | 8386 (92.7) | 9043 |
50–64 | 2173 (12.2) | 15577(87.8) | 17750 |
65–74 | 1978 (17.4) | 9372 (82.6) | 11350 |
75–84 | 1443 (21.7) | 5212 (78.3) | 6655 |
< 85 | 725 (25.9) | 2076 (74.1) | 2801 |
Gender | Women | 3740 (10.3) | 32709 (89.7) | 36449 |
Men | 3943 (12.1) | 2859 (87.9) | 32534 |
Treatment staff | Yes | 10 (4.4) | 217 (95.6) | 227 |
No | 6051 (10.8) | 49776 (89.2) | 55827 |
Smoking history | Yes | 92 (10.8) | 759 (89.2) | 851 |
No | 7591 (11.1) | 60541 (88.9) | 68132 |
Opium use history | Yes | 712 (16.3) | 3665 (83.7) | 4377 |
No | 6971 (10.8) | 57635 (89.2) | 64606 |
Pregnancy | Yes | 5 (.3) | 1865 (99.7) | 1870 |
No | 3835 (10.8) | 30844 (89.2) | 34579 |
A total of 29,705 people (43.1%) had at least one underlying disease. The distribution of underlying diseases is presented in Table 2. The number of people with the clinical spectrum of moderate, severe, and critical COVID-19 was 33,975 (49.2%), 25,671 (37.2%), and 9,355(13.6%), respectively. The most common symptoms were muscle pain (78.3%), cough (44.4%), respiratory distress (43.2%), and fever (42.6%). The distribution of symptoms and signs of hospitalized patients is presented in Table 3, and the distribution of the number of people in different ERS levels based on the outcome (death or discharge) is presented in Table 4.
Table 2
The prevalence of underlying diseases in COVID-19 hospitalized patients in Golestan province, Iran.
Underlying diseases | Outcome | |
Death (n = 7683) | Discharge (n = 61300) | Total (n = 68983) |
Frequency (%) | Frequency (%) | Frequency (%) |
Cardiovascular diseases | 1576 (20.5) | 7507 (12.2) | 9083(13.2) |
Chronic kidney diseases | 324 (4.2) | 1132 (1.8) | 1456(2.1) |
Asthma | 353 (4.6) | 2376 (3.9) | 2729(4.0) |
Other chronic lung diseases Except asthma | 199 (2.6) | 940 (1.5) | 1139(1.7) |
Chronic neurological disorders | 156 (2.0) | 736 (1.2) | 892(1.3) |
Hypertension | 2143 (27.9) | 11522 (18.8) | 13665(19.8) |
Diabetes | 1708 (22.2) | 9015 (14.7) | 10723(15.5) |
Chronic hematological disease | 52 (0.7) | 379 (0.6) | 431(0.6) |
Chronic liver diseases | 71 (0.9) | 271 (0.4) | 342(0.5) |
Cancers | 274 (3.6) | 897 (1.5) | 1171(1.7) |
HIV/AIDS | 6 (0.1) | 23 (0.0) | 29(0.0) |
Immunodeficiency (acquired/congenital) | 23 (0.3) | 155 (0.3) | 178(0.3) |
Other chronic diseases | 884 (11.5) | 5200 (8.5) | 6084(8.8) |
Table 3
Clinical and paraclinical charchteristics of COVID-19 hospitalized patients in Golestan province, Iran
Clinical or preclinical characteristics | Outcome |
Death (n = 7683) | Discharge (n = 61300) | Total (n = 68983) |
Frequency (%) | Frequency (%) | Frequency (%) |
Fever | 2429 (31.6) | 26926 (43.9) | 29355(42.6) |
Cough | 2645 (34.4) | 27966 (45.6) | 30611(44.4) |
Muscle pain | 1218 (15.9) | 13748 (22.4) | 14966(21.7) |
Respiratory distress | 4560 (59.4) | 25220 (41.1) | 29780(43.2) |
Loss of consciousness | 1763 (22.9) | 2462 (4.0) | 4225(6.1) |
Loss/ reduction sense of smell | 34 (0.4) | 535 (0.9) | 569(0.8) |
Loss/reduction of sense of taste | 22 (0.3) | 449 (0.7) | 471(0.7) |
convulsions | 67 (0.9) | 712 (1.2) | 779(1.1) |
Headache | 320 (4.2) | 5752(9.5) | 6072(8.9) |
Dizziness | 174 (2.3) | 2119 (3.5) | 2293(3.4) |
Chest pain | 196(2.6) | 2490(4.1) | 2686(4.0) |
paresis of organs | 39(0.5) | 236 (0.4) | 275(0.4) |
Limb plegia | 35(0.5) | 182 (0.3) | 217(0.3) |
Stomach ache | 124 (1.6) | 1718 (2.8) | 1842(2.7) |
Nausea | 413 (5.4) | 6285 (10.3) | 6698(9.8) |
Vomiting | 273 (3.6) | 5116 (8.4) | 5389(7.9) |
Diarrhea | 194 (2.5) | 3465(5.7) | 3659(5.3) |
Anorexia | 766(10.1) | 8037(13.2) | 8803(12.9) |
Inflammation /lesion skin | 9(0.1) | 124 (0.2) | 133(0.2) |
Intubation | 2708 (35.2) | 1611(2.6) | 4319(6.3) |
Oxygen therapy | 2203(19.8) | 8949(80.2) | 11152(20.0) |
PCR test done | 5893(76.7) | 46719 (76.2) | 52612(76.3) |
Number of breaths per minute on Admission (breaths/min) | < 5 | 125(2.1) | 18(0.0) | 143(0.3) |
5–10 | 109 (1.8) | 85(0.2) | 194(0.3) |
10–14 | 481 (7.9) | 2610 (5.2) | 3091(5.5) |
14–18 | 1270(21.0) | 9999(20.0) | 11269(20.1) |
18–22 | 2529(41.7) | 26252 (52.5) | 28781(51.3) |
22–28 | 1051(17.3) | 7676 (15.4) | 8727(15.6) |
28 < | 496(6.5) | 3353(6.7) | 3849(6.9) |
Hospitalization frequency | 1time | 6205(80.8) | 46458(75.8) | 52663(76.3) |
2 time | 1163(15.1) | 10031(16.4) | 11194(16.2) |
2 times< | 315(4.1) | 4811(7.8) | 5126(74.5) |
Arterial oxygen level at the time of admission | 93%< | 2426 (31.6) | 43814 (71.5) | 46240(67.0) |
93%> | 5257 (68.4) | 17486 (28.5) | 22743(33.0) |
Hospitalization ward | Intensive Care Unit | 3029(39.4) | 4037(6.6) | 7066(10.2) |
General | 2266(29.5) | 31154(50.8) | 33420(48.4) |
Respiratory Isolation | 2388(31.1) | 26109 (42.6) | 28497(41.3) |
Covid-19 PCR Test results | Positive | 3555(60.5) | 22310(36.4) | 25865(49.6) |
Imaging results (X-RAY/ CT Scan) | Symptomatic | 3345(95.7) | 23289(93.6) | 26634(93.8) |
The case fatality rate (CFR) of hospitalized patients with COVID-19 was 11.1% during the period under review. Also, the results show that the CFR followed a decreasing trend during this period despite significant fluctuations (Fig. 2). The mean (SD) age of deceased individuals was 63.34 (18.46) years, compared to 47.56 (24.01) years in those who survived. The highest CFR was observed in the age group above 85 years (25.9%). Death was higher in men (12.1%) than women (10.3%). The median (IQR) duration of hospital stay was 4 (5) days, and the survival probability of patients according to Kaplan-Meier analysis was 75%, 50%, and 25% on days 14, 25, and 44 of hospitalization, respectively.
The log-rank test results of factors affecting the duration of hospitalization indicate that the duration of hospitalization differed with age groups, gender, ERS levels, underlying diseases, and COVID-19 severity (P < 0.001 for all). With increased ERS levels, COVID-19 severity, and age (except for the 18–29 and 30–39 years age groups), the duration of hospitalization decreased. The median duration of hospitalization in patients with moderate, severe, and critical COVID-19 was 50, 28, and 13 days, respectively. This duration was shorter (23 days) in those with an underlying disease than those without an underlying disease (29 days). It was 26 days in women and 25 days in men (Fig. 3).
In the Cox survival analysis, considering the non-establishment of Cox’s proportional hazards assumption for variables such as age, gender, and disease severity classification, using Schoenfeld residuals and the extended Cox model, we considered the interaction effect of time with the mentioned variables. The raw relationship between the length of hospital stay and the ERS level showed that the risk of death at medium, high, and very high ERS levels, compared to the low-risk level, increased by 20%, 24%, and 48%, respectively (P < 0.001 for all). After adjusting for variables such as age, gender, city of residence, disease severity, and underlying diseases, at medium, high, and very high ERS levels compared to the low-risk level, the risk of death increased by 19%, 26%, and 56%, respectively (P < 0.001 for all) (Table 4).
Table 4
The association of Epidemic Risk Status and COVID-19 mortality using cox regression analysis.
Epidemic Risk Status | Outcome | Unadjusted Hazard Ratio (95% CI ) | P-value | Adjusted Hazard Ratioa (95% CI) | P-value |
Death Number (%) | Discharge Number (%) |
Low risk | 497 (7.7) | 5993 (92.3) | Ref. | - | Ref | - |
Moderate risk | 2094 (10.1) | 18715 (89.9) | 1.20 (1.09–1.32) | < 0.001 | 1.19 (1.08–1.31) | < 0.001 |
High risk | 1647 (10.9) | 13471 (89.1) | 1.24 (1.22–1.37) | < 0.001 | 1.26 (1.14–1.40) | < 0.001 |
Very high risk | 3380(13.1) | 22454 (86.9) | 1.48 (1.35–1.63) | < 0.001 | 1.56 (1.42–1.72) | < 0.001 |
aAdjusted for gender, age, city of residence, disease severity classification, underlying diseases.