Impact of Smoking on COVID-19 Symptoms in Non-Vaccinated Patients: A Matched Observational Study from Qatar

Figures & data

Table 1 Baseline Characteristics of Study Participants Based on Their Smoking Status. Data are Presented as Mean ± Standard Deviation or as Number of Subjects (Percentage)

Characteristics	Smokers N= 2952 (25.23)	Non-Smokers N= 8749 (74.77)	P value
Age (years)	34.53 ± 9.631	34.44 ± 9.618
Male sex	2872 (97.3)	8513 (97.3)
Nationality
Indian	745 (25.2)	2229 (25.5)
Qatari	448 (15.2)	1327 (15.2)
Other	2504 (59.6)	7422 (59.3)
Comorbidities
Diabetes	186 (6.3)	531 (6.1)	0.650
Cardiovascular	173 (5.9)	486 (5.6)	0.534
Asthma	32 (1.08)	79 (0.9)	0.380
Respiratory	13 (0.4)	32 (0.4)	0.571
Renal	8 (0.3)	15 (0.2)	0.291
Neurological	2 (0.1)	5 (0.1)	0.839
Hepatic	3 (0.1)	4 (0.05)	0.283
Thyroid	6 (0.2)	12 (0.1)	0.428
Prior surgeries	4 (0.1)	2 (0.02)	0.03*

Notes: P value is denoted in italics. *p < 0.05.

Table 2 The COVID-19 Symptoms Based on Patients’ Smoking Status. Data are Presented as Number of Subjects (Percentage)

Symptoms	Smokers N= 2952 (25.23)	Non-Smokers N= 8749 (74.77)	P value
Any symptom	2222 (75.3)	5495 (62.8)	< 0.001
Fever	1435 (48.6)	3784 (43.3)	< 0.001
Cough	936 (31.7)	2650 (30.3)	0.148
Headache	894 (30.3)	1899 (21.7)	< 0.001
Muscle ache	820 (27.8)	1796 (20.5)	< 0.001
Sore throat	653 (22.1)	1601 (18.3)	< 0.001
Chills	236 (8.0)	553 (6.3)	< 0.05
Shortness of breath	225 (7.6)	506 (5.8)	< 0.001
Diarrhea	174 (5.9)	358 (4.1)	< 0.001
Abdominal pain	151 (5.1)	357 (4.1)	< 0.05

Note: P value is denoted in italics.

Abbreviations: ACE2, angiotensin converting enzyme 2; ANG, ACE/angiotensin; ARDS, acute respiratory distress syndrome; COPD, chronic obstructive pulmonary disease; COVID-19, coronavirus disease 2019; CRP, C-reactive protein; IPF, idiopathic pulmonary fibrosis; MoPH, Ministry of Public Health; nAChRs, nicotinic acetylcholine receptors; qSOFA, quick sequential organ failure assessment; RAS, renin angiotensin system; RT-PCR, reverse-transcription-polymerase chain reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2; SD, standard deviation; SPSS, Statistical Package for the Social Sciences; TNF-α, tumor necrosis factor-alpha; TMPRSS2, transmembrane serine protease 2.

Figure 1 Bar chart showing the percentage of COVID-19 patients who experienced any COVID-19 related symptoms stratified based on their smoking status.

Figure 2 Bar chart showing the rate of developing known COVID-19 symptoms based on the patients’ smoking status.