1.Subjects
This was a key research and development program of the Ministry of Science and Technology in 2017, and the subject was the tobacco-dependent patients who were successively enrolled for quit smoking intervention from December 2018 to December 2019. Quit smoking campaign was conducted in 19 Beijing communities to recruit and screen smokers willing to quit. The investigators and doctors in quit smoking outpatient conducted one-to-one face-to-face questionnaire survey, carbon monoxide blowing test, and pulmonary function test on included smokers. Based on the test results, the doctor formulated a specific quit smoking program for each subject, including whether to consume quit smoking drugs, daily dose, daily smoking reduction schedule, and precautions. Throughout the research, the subjects would receive a three-month quit smoking intervention and six-month follow-up. From March 2020 to April 2020, the research team recruited and trained telephone investigators. Such information as smoking status and willingness to quit smoking during epidemic period were updated timely by one-to-one telephone follow-up.
Inclusion criteria: ①18 years old and above; ②permanent residents in Beijing community; ③smokers, including regular smokers (smoking more than one cigarette per day, continuous or cumulative for 6 months [6]), occasional smokers (smoking cigarettes more than 4 times a week, but less than one cigarette per day on average); ④ communicate fluently and be willing to get involved in the survey. “quit smoking” refers to 7-day quit rate. The subjects reported that they quitted smoking ≥ 7d [7]. “No quit” refers to those who still smoke during survey, including those who had quit smoking but relapsed. In the final telephone survey, 388 people trying to quit smoking were successfully followed up. 177 people said they rejected the telephone survey, and 120 people failed to be connected after the investigator who tried to contact them by phone for many times.
2. Research Contents
Investigation contents before outbreak include: (1) Demographic information, including information such as age, gender, marital status, and education level; (2) Tobacco use, including daily smoking and smoking time; (3) Fagerstrom Test of Nicotine Dependence (FTND); (4) Assessment Scale of Willingness to Quit Smoking.
Telephone follow-up contents during the epidemic period include: (1) Daily home stay time in the past two weeks. The answers include: almost all day, 80–90% of the time, 50–80% of the time, and less than 50% of the time; (2) Words to describe psychological mood during epidemic period? The answers include: suspect, anxiety, panic, distress, calmness, and the same as usual. “Calmness” refers to the subject’s ability to think rationally about the epidemic, and “the same as usual” refers to the indifferent attitude; (3) Smoking behavior of the people trying to quit smoking, including daily smoking, resumption of smoking thought because of epidemic (it refers to relapse in case of already having quit); (4) Fagerstrom Test of Nicotine Dependence (FTND); (5) If smoking continues, the main reason for the smoking behavior, answers include: refreshing, relief of sorrow and boredom, recreation, socializing, intimation, curiosity, influence by the elderly, alleviation of stress, smoking addiction; (6) Assessment Scale of Willingness to Quit Smoking.
Fagerstrom Test of Nicotine Dependence (FTND) includes 6 items, and each item is scored by 0–3 points, representing the dependence in ascending order. Nicotine dependence is judged based on 6 items, including 3 degrees of dependence: mild: 0–3 points; moderate: 4–6 points; severe: 7 points or more. The Scale was first compiled by the scholar Fagerstrom, et al. in 1989 and revised by Heatherton, et al. in 1991. The Chinese version was translated and introduced by Huang CL, et al. in 2006 and its structural validity was preliminarily verified. The Cronbach’s α coefficient of the Chinese version of the Scale is 0.658 [8], indicating that its internal consistency reliability is acceptable.
The assessment scale of willingness to quit smoking was designed by the research team to assess the subjects’ willingness to quit smoking. The Scale contains ten items, subject to Likert 5-point scoring standard, “very non-conforming” rated as 1 point, “relatively non-conforming” rated as 2 points, “general” rated as 3 points, “relatively conforming” rated as 4 points, and “very conforming" is rated as 5 points. The higher the score, the stronger the willingness to quit smoking. By calculating the total score of each subject, it was divided into very low willingness to quit smoking (total score < 10 points), relatively low (10 points ≤ total score < 19 points), general (20 points ≤ total score < 29 points), relatively high (30 points ≤ total score < 39 points), very high (total score ≥ 40 points). The Cronbach's ααcoefficient was tested to be 0.805, the KMO value 0.895, and the Bartlett value is 872.096 (P < 0.001). After the maximum variance rotation, the four factors are extracted and the cumulative explanation is 86%, indicating that the scale has a higher reliability [3−4].
3. Statistical Analysis
IBM SPSS Statistics 22.0 and R 2.15.3 software were used for propensity score matching and statistical analysis. Propensity Score Matching (PSM) is a statistical method commonly used to process observational research data. This method is used to mitigate influence of data bias and confounder for more reasonable comparison on the trial group and control group. On this study, subjects were divided into two groups, those who had quit smoking and those who had not quit smoking. Nearest neighbor matching (NNM) was used. Based on the propensity score of the subjects in the quitter group, seek those among non-quitters nearest to the score. Set the caliper value of the propensity score as 0.1, perform a 1:2 pairing, and conduct subsequent analysis by the matching result. The matching variable is whether quit smoking is successful. The matching conditions include whether to consume quit smoking drug, or receive regular follow-up. Finally, 137 cases of quitters and 211 cases of non-quitters were successfully matched, with a total of 348 cases.
Besides, a descriptive analysis method was adopted to conduct statistics of the overall distribution of people trying to quit smoking during the epidemic period, such as home stay time, psychological mood, smoking behavior, and willingness to quit smoking. The measurement data are expressed as‾x ± s, and the inter-group comparison uses t test. The count data are expressed by percentage (%). χ2 test and the rank sum test were used to conduct correlation analysis of home stay time, psychological mood, smoking reason of people trying to quit smoking and smoking change and willingness to quit smoking before and after COVID-19. P < 0.05 means that the difference was statistically significant.
4. Analysis Thought
According to research findings of the psychology of people during COVID-19 home quarantine, long-term home quarantine can lead to a series of psychological stress reactions such as loneliness, fear, and anxiety [9]. After surveying community residents, Yang Liquan [10], et al. found that most residents have varying degrees of fear and distress. Meanwhile, home quarantine changed the daily lifestyle of people. Due to extended leisure time, change of life cycle, narrow living space, singular lifestyle and less socializing with the outside world, people are prone to negative mood [11]. Studies have shown that mood is related to smoking behavior. Smokers were not aware of the mechanism of nicotine addiction and believed that tobacco can lift people up. However, the effect of smoking may be magnified when there is negative mood[4, 12]. For the smokers trying to quit smoking in this study, home quarantine during the epidemic period made them accept life events and environmental stressors, which might also produce negative psychological mood. Psychosocial social factor is an important factor to influence nicotine dependence, as well as smokers' willingness to quit smoking and smoking status. The success of quit smoking is affected by many factors, including different smoking status, motivation of quitting smoking, whether appropriate techniques and methods are available, and temptations during quit smoking period [5]. After COVID-19 outbreak, the results of the telephone follow-up showed that the average daily smoking of 165 people trying to quit smoking changed over that before outbreak, accounting for 42.5% of people receiving telephone survey. And the difference of distribution of smoking change in the two groups of subjects was statistically significant (P < 0.05), see Table 1. Further comparison of the daily smoking, nicotine dependence, and evaluation of the willingness to quit smoking of people trying to quit smoking showed that the distribution difference compared with that before outbreak was statistically significant (all P < 0.05), see Table 2. According to findings, during epidemic period, the average daily smoking of the people trying to quit smoking decreased slightly, the quit smoking rate increased significantly, nicotine dependence decreased somewhat, and the willingness to quit smoking increased significantly than before the outbreak. It showed that the smoking behavior of subjects changed, and changed for better than before the outbreak.
Table 1
Comparison of changes in daily average smoking between the two groups of people trying to quit smoking before and after The epidemic of COVID-19 period [n(%)]
Smoking quantity change
|
Have you successfully quit smoking?
|
Z
|
p
|
No
|
Yes
|
-35~
|
6(2.6)
|
7(4.5)
|
-2.366
|
0.018
|
-10~
|
41(17.6)
|
32(20.6)
|
0~
|
129(55.4)
|
94(60.6)
|
1~
|
50(21.5)
|
22(14.2)
|
10~
|
7(3.0)
|
0(0.0)
|
Total
|
233(100.0)
|
155(100.0)
|
Table 2 Comparison of smoking status, nicotine dependence and willingness to quit smoking among people trying to quit smoking before and after the epidemic of COVID-19 period [`x±s]
Index
|
n
|
Mean ± standard deviation
|
Quit smoking rate (%)
|
t
|
p
|
Average daily smoking before outbreak
|
388
|
7.77±8.405
|
25.0
|
3.029
|
0.003
|
Average daily smoking during epidemic period
|
388
|
7.10±8.473
|
39.9
|
Nicotine dependence before outbreak
|
388
|
4.35±2.518
|
-
|
18.988
|
<0.001
|
Nicotine dependence during epidemic period
|
388
|
1.91±2.449
|
-
|
Willingness to quit smoking before outbreak
|
388
|
19.78±9.103
|
-
|
-22.552
|
<0.001
|
Willingness to quit smoking during epidemic period
|
388
|
38.17±12.377
|
-
|
However, the subjects in this study had received three-month quit smoking services and six-month follow-up, which overlapped with the epidemic period. And again, use of quit smoking drugs and regular follow-ups might also was related to change in smoking behavior of people trying to quit smoking, see Fig. 1. In order to control influence of confounders, the main content of quit smoking intervention was planned to be used as the matching conditions for propensity score matching. After matching, relevant factors could be controlled. And again, further analysis of relevant factors for changes in smoking behavior of people trying to quit smoking during epidemic period would be conducted to define correlation between people's home stay time, psychological mood, smoking status and their behavior change.
5. Ethics Committee Approval
This study has been approved by the Ethics Committee of the Capital Medical University (Z2019SY007), and an informed consent form signed with the subject before study. In addition, this study has been registered in the official website of Chinese Clinical Trial Registry (Chictr1900024991).