Interventions to increase personal protective behaviours to limit the spread of respiratory viruses: A rapid evidence review and meta-analysis

PURPOSE: Increasing personal protective behaviours is critical for stopping the spread of respiratory viruses, including SARS-CoV-2: we need evidence to inform how to achieve this. We aimed to synthesise evidence on interventions to increase six personal protective behaviours (e.g. hand hygiene, face mask use) to limit the spread of respiratory viruses. METHODS: We used best practice for rapid evidence reviews. We searched Ovid MEDLINE and Scopus. Studies conducted in adults or children with active or passive comparators were included. We extracted data from published intervention descriptions on study design, intervention content, delivery mode, population, setting, mechanism(s) of action, acceptability, practicability, effectiveness, affordability, spill-over effects and equity impact. Study quality was assessed with Cochrane's risk of bias tool. A narrative synthesis and random-effects meta-analyses were conducted. RESULTS: We identified 39 studies conducted across 15 countries. Interventions targeted hand hygiene (n=30) and/or face mask use (n=12) and used two- or three-arm study designs with passive comparators. Interventions were typically delivered face-to-face and included a median of three behaviour change techniques. The quality of included studies was low. Interventions to increase hand hygiene (k=6) had a medium, positive effect (_d_=0.62, 95% CI=0.43-0.80, _p_<.001, I2=81.2%). Interventions targeting face mask use (k=4) had mixed results, with an imprecise pooled estimate (OR=4.14, 95% CI=1.24-13.79, _p_<.001, I2=89.67%). Between-study heterogeneity was high. CONCLUSIONS: We found low-quality evidence for positive effects of hand hygiene interventions, with unclear results for face mask use interventions. There was a lack of evidence for interventions targeting most behaviours of interest within this review.

Face masks to prevent community transmission of viral respiratory infections: A rapid evidence review using Bayesian analysis

Background: Face masks have been proposed as an important way of reducing transmission of viral respiratory infections, including SARS-CoV-2. Objective: To assess the likelihood that wearing face masks in community settings reduces transmission of viral respiratory infections. Methods: We conducted a rapid evidence review and used a Bayesian statistical approach to analysing experimental and observational studies conducted in community-dwelling children and adults that assessed the effectiveness of face mask wearing (vs. no face masks) on self-reported, laboratory-confirmed, or clinically diagnosed viral respiratory infections. Results: Eleven RCTs and 10 observational studies met the inclusion criteria. The calculation of Bayes factors and cumulative posterior odds from the RCTs showed a moderate likelihood of a small effect of wearing surgical face masks in community settings in reducing self-reported influenza-like illness (ILI) (cumulative posterior odds = 3.61). However, the risk of reporting bias was high and evidence of reduction of clinically- or laboratory-confirmed infection was equivocal (cumulative posterior odds = 1.07 and 1.22, respectively). Observational studies yielded evidence of a negative association between face mask wearing and ILI but with high risk of confounding and reporting bias. Conclusions: Available evidence from RCTs is equivocal as to whether or not wearing face masks in community settings results in a reduction in clinically- or laboratory-confirmed viral respiratory infections. No relevant studies concerned SARS-CoV-2 or were undertaken in community settings in the UK.

Smoking and COVID Living Review (v11): a bayesian analysis

AIMS: To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. DESIGN: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv. SETTING: Community or hospital. No restrictions on location. PARTICIPANTS: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. MEASUREMENTS: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good', ‘fair' and ‘poor'). FINDINGS: v11 (searches up to 2021-02-16) included 405 studies with 62 ‘good' and ‘fair' quality studies included in unadjusted meta-analyses. 121 studies (29.9%) reported current, former and never smoking status with the remainder using broader categories. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR = 0.71, 95% Credible Interval (CrI) = 0.61-0.82, τ = 0.34). Data for former smokers were inconclusive (RR = 1.03, 95% CrI = 0.95-1.11, τ = 0.17) but favoured there being no important association (4% probability of RR ≥1.1). Former compared with never smokers were at increased risk of hospitalisation (RR = 1.19, CrI = 1.1-1.29, τ = 0.13), greater disease severity (RR = 1.8, CrI = 1.27-2.55, τ = 0.46) and mortality (RR = 1.56, CrI = 1.23-2, τ = 0.43). Data for current smokers on hospitalisation, disease severity and mortality were inconclusive (RR = 1.1, 95% CrI = 0.99-1.21, τ = 0.15;RR 1.26, 95% CrI = 0.92-1.73, τ = 0.32;RR = 1.12, 95% CrI = 0.84-1.47, τ = 0.42, respectively) but favoured there being no important associations with hospitalisation and mortality (49% and 56% probability of RR ≥1.1, respectively) and a small but important association with disease severity (83% probability of RR ≥1.1). CONCLUSIONS: Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection while former smokers appear to be at increased risk of hospitalisation, greater disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal. v7 of this living review article has been published in _Addiction_ [https://doi-org.libproxy.ucl.ac.uk/10.1111/add.15276]

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 10)

AIMS: To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. DESIGN: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv. SETTING: Community or hospital. No restrictions on location. PARTICIPANTS: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. MEASUREMENTS: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good', ‘fair' and ‘poor'). FINDINGS: Version 10 (searches up to 15 December 2020) included 345 studies with 52 ‘good' and ‘fair' quality studies included in unadjusted meta-analyses. One-hundred-and-one studies (29.3%) reported current, former and never smoking status with the remainder using broader categories. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR = 0.69, 95% Credible Interval (CrI) = 0.58-0.82, τ = 0.36). Data for former smokers were inconclusive (RR = 1.03, 95% CrI = 0.94-1.13, τ = 0.18) but favoured there being no important association (8% probability of RR ≥1.1). Former compared with never smokers were at increased risk of hospitalisation (RR = 1.18, CrI = 1.07-1.31, τ = 0.14), greater disease severity (RR = 1.52, CrI = 1.12-2.06, τ = 0.29) and mortality (RR = 1.40, 95% CrI = 1.20-1.64, τ = 0.19). Data for current smokers on hospitalisation, disease severity and mortality were inconclusive (RR = 1.08, CrI = 0.95-1.23, τ = 0.18;RR = 1.26, CrI = 0.85-1.93, τ = 0.34;RR = 1.05, 95% CrI = 0.77-1.41, τ = 0.39, respectively) but favoured there being no important associations with hospitalisation and mortality (31% and 38% probability of RR ≥1.1, respectively) and a small but important association with disease severity (80% probability of RR ≥1.1). CONCLUSIONS: Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection while former smokers appear to be at increased risk of hospitalisation, greater disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal. v7 of this living review article has been published in _Addiction _and is available here https://doi-org.libproxy.ucl.ac.uk/10.1111/add.15276

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 11)

AIMS: To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. DESIGN: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv. SETTING: Community or hospital. No restrictions on location. PARTICIPANTS: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. MEASUREMENTS: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good', ‘fair' and ‘poor'). FINDINGS: v11 (searches up to 2021-02-16) included 405 studies with 62 ‘good' and ‘fair' quality studies included in unadjusted meta-analyses. 121 studies (29.9%) reported current, former and never smoking status with the remainder using broader categories. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR = 0.71, 95% Credible Interval (CrI) = 0.61-0.82, τ = 0.34). Data for former smokers were inconclusive (RR = 1.03, 95% CrI = 0.95-1.11, τ = 0.17) but favoured there being no important association (4% probability of RR ≥1.1). Former compared with never smokers were at increased risk of hospitalisation (RR = 1.19, CrI = 1.1-1.29, τ = 0.13), greater disease severity (RR = 1.8, CrI = 1.27-2.55, τ = 0.46) and mortality (RR = 1.56, CrI = 1.23-2, τ = 0.43). Data for current smokers on hospitalisation, disease severity and mortality were inconclusive (RR = 1.1, 95% CrI = 0.99-1.21, τ = 0.15;RR 1.26, 95% CrI = 0.92-1.73, τ = 0.32;RR = 1.12, 95% CrI = 0.84-1.47, τ = 0.42, respectively) but favoured there being no important associations with hospitalisation and mortality (49% and 56% probability of RR ≥1.1, respectively) and a small but important association with disease severity (83% probability of RR ≥1.1). CONCLUSIONS: Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection while former smokers appear to be at increased risk of hospitalisation, greater disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal. v7 of this living review article has been published in _Addiction_ [https://doi-org.libproxy.ucl.ac.uk/10.1111/add.15276]

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 12)

AIMS: To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity in hospitalised patients, and iv) mortality from SARS-CoV-2/COVID-19 disease. DESIGN: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv . SETTING: Community or hospital. No restrictions on location. PARTICIPANTS: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. MEASUREMENTS: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good,' ‘fair' and ‘poor'). FINDINGS: v12 (searches up to 2021-07-18) included 547 studies with 87 ‘good' and ‘fair' quality studies included in unadjusted meta-analyses. 171 studies (31.3%) reported current, former and never smoking status with the remainder using broader categories. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR = 0.67, 95% Credible Interval (CrI) = 0.60-0.75, τ = 0.27). Data for former smokers were inconclusive (RR = 0.99, 95% CrI = 0.94-1.05, τ = 0.12) but favoured there being no important association (<1% probability of RR ≥1.1). Former compared with never smokers were at increased risk of hospitalisation (RR = 1.27, CrI = 1.15-1.40, τ = 0.20), greater disease severity (RR = 1.69, CrI = 1.30-2.22, τ = 0.43) and mortality (RR = 1.59, CrI = 1.34-1.89, τ = 0.37). Current compared with never smokers were at increased risk of greater disease severity (RR 1.3, 95% CrI = 1.01-1.71, τ = 0.32). Data for current smokers on hospitalisation and mortality were inconclusive (RR = 1.10, 95% CrI = 0.97-1.24, τ = 0.23;RR = 1.13, 95% CrI = 0.90-1.40, τ = 0.41, respectively) but favoured there being no important associations (50% and 60% probability of RR ≥1.1, respectively). CONCLUSIONS: Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection and increased risk of greater in-hospital disease severity, while former smokers appear to be at increased risk of hospitalisation, greater in-hospital disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal. This version (v12) will be the last regular update;however, yearly updates may continue as new evidence becomes available. v7 of this living review article has been published in _Addiction_ [https://doi.org/10.1111/add.15276]

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review (version 3)

Background: SARS-CoV-2 is the causative agent of COVID-19, an emergent zoonotic disease which has reached pandemic levels and is designated a public health emergency of international concern. It is plausible that former or current smoking status are associated with infection, hospitalisation and/or mortality from COVID-19. Objective: We aimed to estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19. Methods: We adopted recommended practice for rapid evidence reviews, which involved limiting the search to main databases and having one reviewer extract data and another verify. Published articles and pre-prints were identified via Ovid MEDLINE, medRxiv and expertise within the review team. We included observational studies with community-dwelling or hospitalised adults aged 16 years who had been tested for SARS-CoV-2 infection or diagnosed with COVID-19, providing that data on smoking status were reported. The National Institutes of Health's Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies was used to divide studies into ‘good', ‘fair' and ‘poor' quality to address objectives of this review. Studies were judged as ‘good' quality if they: i) had low levels of missing data on smoking status, ii) used a reliable self-report measure that distinguished between current, former and never smoking status, iii) used biochemical verification of smoking status and iv) adjusted analyses for potential confounding variables. Results: Sixty-seven studies were included, 30 of which were conducted in China, 12 in the US, six in the UK, four in France, three in Mexico, three in Spain, two across multiple international sites, two in Italy, and one each from Iran, Israel, Korea, Kuwait and Switzerland. Eleven studies did not state the source for information on smoking status. Fifty-one studies reported current and/or former smoking status but had high levels of missing data and/or did not explicitly state whether the remaining participants were never smokers. Notwithstanding recording uncertainties, compared with national prevalence estimates, recorded current and former smoking rates in most studies were lower than expected. In six ‘fair' quality studies, no significant difference was observed between current and never (RR = 0.78, 95% CI = 0.55-1.11, p = .17, I2 = 92%) or former and never smokers (RR = 1.07, 95% CI = 0.95-1.20, p = .24, I2 = 61%) in the risk of testing positive for SARS-CoV-2. In five ‘fair' quality studies, there was no significant difference between current and never (RR = 1.12, 95% CI = 0.74-1.69, p = .48, I2 = 84%) or former and never smokers (RR = 1.21, 95% CI = 0.82-1.79, p = .24, I2 = 81%) in the risk of requiring admission to hospital following diagnosis of COVID-19. In three ‘fair' quality studies, current smokers were at increased risk of greater disease severity compared with never smokers (RR = 1.37, 95% CI = 1.07-1.75, p = .01, I2 = 0%). No significant difference was observed between former and never smokers (RR = 1.51, 95% CI = 0.82-2.80, p = .19, I2 = 81%). In three ‘fair' quality studies, there were inconsistent results on mortality from COVID-19 in current and former compared with never smokers. Conclusions: Across 67 observational studies, there is substantial uncertainty about the associations between smoking and COVID-19 outcomes. The recorded smoking prevalence in hospitalised patients was lower than national estimates but this observation is inconsistent with there being no evidence of increased admission to hospital from five ‘fair' quality studies of people who tested positive. There was limited evidence from ‘fair' quality studies that current compared with never smoking is associated with greater disease severity in those hospitalised for COVID-19. Implications: Unrelated to COVID-19, smokers are at a greater risk of a range of serious health problems, requiring them to be admitt d to hospital. Given uncertainty around the association of smoking with COVID-19, smoking cessation remains a public health priority and high-quality smoking cessation advice including recommendations to use alternative nicotine should form part of public health efforts during this pandemic.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review

Background: SARS-CoV-2 is the causative agent of COVID-19, an emergent zoonotic disease which has reached pandemic levels and is designated a public health emergency of international concern. It is plausible that former or current smoking status are risk factors for infection, hospitalisation and/or mortality from COVID-19. Objective: We aimed to estimate the rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 stratified by smoking status. Methods: We adopted recommended practice for rapid evidence reviews, which involved limiting the search to main databases and having one reviewer extract data and another verify. Published articles and pre-prints were identified via MEDLINE, EPPI-Mapper and expertise within the review team. We included observational studies with community-dwelling or hospitalised adults aged 16 years who had been tested for SARS-CoV-2 or were diagnosed with COVID-19, providing that data on smoking status were reported. Studies were judged as high quality if they explicitly recorded current, former and never smoking status with low levels of missing data. Results: Twenty-eight studies were included, 22 of which were conducted in China, three in the US, one in Korea, one in France and one across multiple international sites with data predominantly collected in the UK. Eight studies did not state the source for information on smoking status. Twenty-five studies reported current and/or former smoking status but had high levels of missing data and/or did not explicitly state whether the remaining participants were never smokers. Notwithstanding these uncertainties, compared with national prevalence estimates, recorded current and former smoking rates in the included studies were generally lower than expected. Within the only study to report community SARS-CoV-2 infection by smoking status, current smokers appeared more likely to be tested but the rate for positive tests was lower. In two high-quality studies, results from a fixed-effects meta-analysis provided no evidence for an increased risk of hospitalisation among 657 current/former smokers who tested positive in the community (RR = 1.03, 95% CI = 0.93-1.14, p = 0.57). Among 1370 people hospitalised across two high-quality studies, there was greater disease severity in current/former smokers compared with never smokers (RR = 1.43, 95% CI = 1.15-1.77, p = .002). Three studies reporting on mortality did not explicitly state never smoking status. Conclusions: Across 28 observational studies, there is substantial uncertainty arising from the recording of smoking status on whether current and/or former smoking status is associated with SARS-CoV-2 infection, hospitalisation or mortality. There is low quality evidence that current and former smoking compared with never is associated with greater disease severity in those hospitalised for COVID-19. Implications: Unrelated to COVID-19, smokers are at a greater risk of a range of serious health problems requiring them to be admitted to hospital. Given uncertainty around the association of smoking with COVID-19, smoking cessation remains a public health priority and high-quality smoking cessation advice should form part of public health efforts during this pandemic.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review (version 6)

Aims: : To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. Design: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via Ovid MEDLINE and medRxiv. Setting: Community or hospital with no restrictions on location. Participants: Adults who had received a test for SARS-CoV-2 infection or a diagnosis of COVID-19. Measurements: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed. Findings: Version 6 with searches up to 17 July 2020 included 174 studies with 26 included in meta-analyses. Thirty-nine studies reported current, former and never smoking status. Notwithstanding recording uncertainties, compared with adult national prevalence estimates, recorded current smoking rates were generally lower than expected. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR = 0.74, 95% Credible Interval (CrI) = 0.56-0.97, τ = 0.46). Former compared with never smokers were at somewhat increased risk of infection but data were inconclusive (RR = 1.06, 95% CrI = 0.94-1.20, τ = 0.19). Current (RR = 1.05, CrI = 0.82-1.34, τ = 0.29) and former (RR = 1.20, CrI = 1.03-1.44, τ = 0.19) compared with never smokers were both at somewhat increased risk of hospitalisation with COVID-19, but data for current smokers were inconclusive. Current (RR = 1.15, CrI = 0.80-1.66, τ = 0.29) and former (RR = 1.51, CrI = 1.06-2.15, τ = 0.36) compared with never smokers were at increased risk of greater disease severity, but data for current smokers were inconclusive. Current (RR = 1.89, 95% CrI = 0.77-3.41, τ = 0.51) and former (RR = 1.93, 95% CrI = 1.33-2.66, τ = 0.19) compared with never smokers had increased risk of in-hospital death, but data for current smokers were inconclusive. Conclusions: There is uncertainty about the associations of smoking with COVID-19 outcomes. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current smokers were at reduced risk of infection. Former smokers were at increased risk of hospitalisation, disease severity and mortality, while data for current smokers favoured no important associations but were inconclusive.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 8)

Aims: : To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. Design: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv. Setting: Community or hospital. No restrictions on location. Participants: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. Measurements: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good', ‘fair' and ‘poor'). Findings: Version 8 (searches up to 22 September 2020) included 256 studies with 36 ‘good' and ‘fair' quality studies included in meta-analyses. Sixty-seven studies (26.2%) reported current, former and never smoking status with the remainder using broader categories. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR=0.72, 95% Credible Interval (CrI) = 0.57-0.89, τ = 0.40). Data for former smokers were inconclusive (RR=1.02, 95% CrI = 0.92-1.13, τ = 0.18) but favoured there being no important association (7% probability of RR ≥1.1). Former compared with never smokers were at somewhat increased risk of hospitalisation (RR=1.19, CrI = 1.03-1.43, τ = 0.17), greater disease severity (RR=1.52, CrI = 1.12-2.05, τ = 0.29) and mortality (RR=1.35, 95% CrI = 1.09-1.73, τ = 0.26). Data for current smokers on hospitalisation, disease severity and mortality were inconclusive (RR=1.06, CrI = 0.82-1.35, τ = 0.27;RR=1.26, CrI = 0.85-1.96, τ = 0.34;RR=1.10, 95% CrI = 0.69-1.67, τ = 0.50, respectively) but favoured there being no important associations with hospitalisation and mortality (35% and 51% probability of RR ≥1.1, respectively) and a small but important association with disease severity (79% probability of RR ≥1.1). Conclusions: Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection while former smokers appear to be at increased risk of hospitalisation, greater disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 7)

Aims: : To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. Design: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv. Setting: Community or hospital. No restrictions on location. Participants: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. Measurements: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good', ‘fair' and ‘poor'). Findings: Version 7 (searches up to 25 August 2020) included 233 studies with 32 ‘good' and ‘fair' quality studies included in meta-analyses. Fifty-seven studies (24.5%) reported current, former and never smoking status. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR=0.74, 95% Credible Interval (CrI) = 0.58-0.93, τ = 0.41). Data for former smokers were inconclusive (RR=1.05, 95% CrI = 0.95-1.17, τ = 0.17) but favoured there being no important association (21% probability of RR ≥1.1). Former compared with never smokers were at somewhat increased risk of hospitalisation (RR=1.20, CrI = 1.03-1.44, τ = 0.17), greater disease severity (RR=1.52, CrI = 1.13-2.07, τ = 0.29), and mortality (RR=1.39, 95% CrI = 1.09-1.87, τ = 0.27). Data for current smokers were inconclusive (RR=1.06, CrI = 0.82-1.35, τ = 0.27;RR=1.25, CrI = 0.85-1.93, τ = 0.34;RR=1.22, 95% CrI = 0.78-1.94, τ = 0.49 respectively) but favoured there being no important associations with hospitalisation and mortality (35% and 70% probability of RR ≥1.1, respectively) and a small but important association with disease severity (79% probability of RR ≥1.1). Conclusions: Due to incomplete recording of smoking status, there is uncertainty about the associations of smoking with COVID-19 outcomes. Current smokers were at reduced risk of SARS-CoV-2 infection. Former smokers were at increased risk of hospitalisation, disease severity and mortality from COVID-19, while data for current smokers inconclusively favoured no large associations with these outcomes.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review (version 4)

Background: SARS-CoV-2 is the causative agent of COVID-19, an emergent zoonotic disease which has reached pandemic levels and is designated a public health emergency of international concern. It is plausible that former or current smoking status is associated with infection, hospitalisation and/or mortality from COVID-19. Objective: We aimed to estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. Methods: This is a living evidence review with frequent updates. We adopted recommended practice for rapid evidence reviews, which involved limiting the search to main databases and having one reviewer extract data and another verify. Published articles and pre-prints were identified via Ovid MEDLINE, medRxiv and expertise within the review team. We included observational or experimental studies with community-dwelling or hospitalised adults aged 16 years who had received a test for SARS-CoV-2 infection or a diagnosis of COVID-19, providing that data on smoking status were reported. Studies were judged as ‘good' quality if they: i) had low levels of missing data on smoking status (i.e.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review (version 5)

Background: SARS-CoV-2 is the causative agent of COVID-19, an emergent zoonotic disease which has reached pandemic levels and is designated a public health emergency of international concern. It is plausible that former or current smoking status is associated with infection, hospitalisation and/or mortality from COVID-19. Objective: We aimed to estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. Methods: This is a living evidence review with frequent updates. We adopted recommended practice for rapid evidence reviews, which involved limiting the search to main databases and having one reviewer extract data and another verify. Published articles and pre-prints were identified via Ovid MEDLINE, medRxiv and expertise within the review team. We included observational or experimental studies with community-dwelling or hospitalised adults aged 16 years who had received a test for SARS-CoV-2 infection or a diagnosis of COVID-19, providing that data on smoking status were reported. Studies were judged as ‘good' quality if they: i) had low levels of missing data on smoking status (i.e.

The association of smoking status with SARS-CoV-2 infection, hospitalisation and mortality from COVID-19: A living rapid evidence review with Bayesian meta-analyses (version 9)

AIMS: To estimate the association of smoking status with rates of i) infection, ii) hospitalisation, iii) disease severity, and iv) mortality from SARS-CoV-2/COVID-19 disease. DESIGN: Living rapid review of observational and experimental studies with random-effects hierarchical Bayesian meta-analyses. Published articles and pre-prints were identified via MEDLINE and medRxiv. SETTING: Community or hospital. No restrictions on location. PARTICIPANTS: Adults who received a SARS-CoV-2 test or a COVID-19 diagnosis. MEASUREMENTS: Outcomes were SARS-CoV-2 infection, hospitalisation, disease severity and mortality stratified by smoking status. Study quality was assessed (i.e. ‘good', ‘fair' and ‘poor'). FINDINGS: Version 9 (searches up to 27 October 2020) included 279 studies with 42 ‘good' and ‘fair' quality studies included in unadjusted meta-analyses. Seventy-nine studies (28%) reported current, former and never smoking status with the remainder using broader categories. Recorded smoking prevalence among people with COVID-19 was generally lower than national prevalence. Current compared with never smokers were at reduced risk of SARS-CoV-2 infection (RR = 0.69, 95% Credible Interval (CrI) = 0.57-0.83, τ = 0.38). Data for former smokers were inconclusive (RR = 1.02, 95% CrI = 0.93-1.12, τ = 0.18) but favoured there being no important association (5% probability of RR ≥1.1). Former compared with never smokers were at somewhat increased risk of hospitalisation (RR = 1.17, CrI = 1.04-1.36, τ = 0.17), greater disease severity (RR = 1.52, CrI = 1.12-2.06, τ = 0.29) and mortality (RR = 1.39, 95% CrI = 1.16-1.69, τ = 0.23). Data for current smokers on hospitalisation, disease severity and mortality were inconclusive (RR = 1.06, CrI = 0.89-1.27, τ = 0.23;RR = 1.26, CrI = 0.86-1.94, τ = 0.34;RR = 1.05, 95% CrI = 0.71-1.49, τ = 0.45, respectively) but favoured there being no important associations with hospitalisation and mortality (32% and 39% probability of RR ≥1.1, respectively) and a small but important association with disease severity (80% probability of RR ≥1.1). CONCLUSIONS: Compared with never smokers, current smokers appear to be at reduced risk of SARS-CoV-2 infection while former smokers appear to be at increased risk of hospitalisation, greater disease severity and mortality from COVID-19. However, it is uncertain whether these associations are causal. v7 of this living review article has been published in _Addiction _and is available here https://doi-org.libproxy.ucl.ac.uk/10.1111/add.15276

The Effect of the First UK COVID-19 Lockdown on Users of the Drink Less App: Interrupted Time Series Analysis of Sociodemographic Characteristics, Engagement, and Alcohol Reduction.

BACKGROUND: The first UK COVID-19 lockdown had a polarizing impact on drinking behavior and may have impacted engagement with digital interventions to reduce alcohol consumption. OBJECTIVE: We examined the effect of lockdown on engagement, alcohol reduction, and the sociodemographic characteristics of users of the popular and widely available alcohol reduction app Drink Less. METHODS: This was a natural experiment. The study period spanned 468 days between March 24, 2019, and July 3, 2020, with the introduction of UK lockdown measures beginning on March 24, 2020. Users were 18 years or older, based in the United Kingdom, and interested in drinking less. Interrupted time series analyses using generalized additive mixed models (GAMMs) were conducted for each outcome variable (ie, sociodemographic characteristics, app downloads and engagement levels, alcohol consumption, and extent of alcohol reduction) for existing (downloaded the app prelockdown) and new (downloaded the app during the lockdown) users of the app. RESULTS: Among existing users of the Drink Less app, there were increases in the time spent on the app per day (B=0.01, P=.01), mean units of alcohol recorded per day (B>0.00 P=.02), and mean heavy drinking (>6 units) days (B>0.00, P=.02) during the lockdown. Previous declines in new app downloads plateaued during the lockdown (incidence rate ratio [IRR]=1.00, P=.18). Among new app users, there was an increase in the proportion of female users (B>0.00, P=.04) and those at risk of alcohol dependence (B>0.00, P=.01) and a decrease in the proportion of nonmanual workers (B>-0.00, P=.04). Among new app users, there were step increases in the mean number of alcohol units per day (B=20.12, P=.03), heavy-drinking days (B=1.38, P=.01), and the number of days the app was used (B=2.05, P=.02), alongside a step decrease in the percentage of available screens viewed (B=-0.03, P=.04), indicating users were using less of the intervention components within the app. CONCLUSIONS: Following the first UK lockdown, there was evidence of increases in engagement and alcohol consumption among new and existing users of the Drink Less app.

White Paper: Open Digital Health - accelerating transparent and scalable health promotion and treatment.

In this White Paper, we outline recommendations from the perspective of health psychology and behavioural science, addressing three research gaps: (1) What methods in the health psychology research toolkit can be best used for developing and evaluating digital health tools? (2) What are the most feasible strategies to reuse digital health tools across populations and settings? (3) What are the main advantages and challenges of sharing (openly publishing) data, code, intervention content and design features of digital health tools? We provide actionable suggestions for researchers joining the continuously growing Open Digital Health movement, poised to revolutionise health psychology research and practice in the coming years. This White Paper is positioned in the current context of the COVID-19 pandemic, exploring how digital health tools have rapidly gained popularity in 2020-2022, when world-wide health promotion and treatment efforts rapidly shifted from face-to-face to remote delivery. This statement is written by the Directors of the not-for-profit Open Digital Health initiative (n = 6), Experts attending the European Health Psychology Society Synergy Expert Meeting (n = 17), and the initiative consultant, following a two-day meeting (19-20th August 2021).

Exploring Users' Experiences With a Quick-Response Chatbot Within a Popular Smoking Cessation Smartphone App: Semistructured Interview Study.

BACKGROUND: Engagement with smartphone apps for smoking cessation tends to be low. Chatbots (ie, software that enables conversations with users) offer a promising means of increasing engagement. OBJECTIVE: We aimed to explore smokers' experiences with a quick-response chatbot (Quit Coach) implemented within a popular smoking cessation app and identify factors that influence users' engagement with Quit Coach. METHODS: In-depth, one-to-one, semistructured qualitative interviews were conducted with adult, past-year smokers who had voluntarily used Quit Coach in a recent smoking cessation attempt (5/14, 36%) and current smokers who agreed to download and use Quit Coach for a minimum of 2 weeks to support a new cessation attempt (9/14, 64%). Verbal reports were audio recorded, transcribed verbatim, and analyzed within a constructivist theoretical framework using inductive thematic analysis. RESULTS: A total of 3 high-order themes were generated to capture users' experiences and engagement with Quit Coach: anthropomorphism of and accountability to Quit Coach (ie, users ascribing human-like characteristics and thoughts to the chatbot, which helped foster a sense of accountability to it), Quit Coach's interaction style and format (eg, positive and motivational tone of voice and quick and easy-to-complete check-ins), and users' perceived need for support (ie, chatbot engagement was motivated by seeking distraction from cravings or support to maintain motivation to stay quit). CONCLUSIONS: Anthropomorphism of a quick-response chatbot implemented within a popular smoking cessation app appeared to be enabled by its interaction style and format and users' perceived need for support, which may have given rise to feelings of accountability and increased engagement.

Changes in Cigarette Smoking and Vaping in Response to the COVID-19 Pandemic in the UK: Findings from Baseline and 12-Month Follow up of HEBECO Study.

This study investigated UK adults' changes in cigarette smoking and vaping during the COVID-19 pandemic and factors associated with any changes. Data were from an online longitudinal study. A self-selected sample (n = 332) of 228 smokers and 155 vapers (51 participants were both smokers and vapers) completed 5 surveys between April 2020 and June 2021. Participants self-reported data on sociodemographics, COVID-19-related, and smoking/vaping characteristics. During the 12 months of observations, among smokers, 45% self-reported a quit attempt (27.5% due to COVID-19-related reasons) since the onset of COVID-19 pandemic and the quit rate was 17.5%. At 12 months, 35.1% of continuing smokers (n = 174) reported smoking less and 37.9% the same, while 27.0% reported an increase in the number of cigarettes smoked/day. Among vapers, 25.0% self-reported a quit attempt (16.1% due to COVID-19-related reasons) and the quit rate was 18.1%. At 12 months, 47.7% of continuing vapers (n = 109) reported no change in the frequency of vaping/hour, while a similar proportion reported vaping less (27.5%) and more (24.8%). Motivation to quit smoking and being younger were associated with making a smoking quit attempt and smoking cessation. Being a cigarette smoker was associated with vaping cessation. Among a self-selected sample, COVID-19 stimulated more interest in reducing or quitting cigarette smoking than vaping.

Interventions to increase personal protective behaviours to limit the spread of respiratory viruses: A rapid evidence review and meta-analysis.

PURPOSE: Increasing personal protective behaviours is critical for stopping the spread of respiratory viruses, including SARS-CoV-2: We need evidence to inform how to achieve this. We aimed to synthesize evidence on interventions to increase six personal protective behaviours (e.g., hand hygiene, face mask use, maintaining physical distancing) to limit the spread of respiratory viruses. METHODS: We used best practice for rapid evidence reviews. We searched Ovid MEDLINE and Scopus. Studies conducted in adults or children with active or passive comparators were included. We extracted data on study design, intervention content, mode of delivery, population, setting, mechanism(s) of action, acceptability, practicability, effectiveness, affordability, spill-over effects, and equity impact. Study quality was assessed with Cochrane's risk-of-bias tool. A narrative synthesis and random-effects meta-analyses were conducted. RESULTS: We identified 39 studies conducted across 15 countries. Interventions targeted hand hygiene (n = 30) and/or face mask use (n = 12) and used two- or three-arm study designs with passive comparators. Interventions were typically delivered face-to-face and included a median of three behaviour change techniques. The quality of included studies was low. Interventions to increase hand hygiene (k = 6) had a medium, positive effect (d = .62, 95% CI = 0.43-0.80, p < .001, I2 = 81.2%). Interventions targeting face mask use (k = 4) had mixed results, with an imprecise pooled estimate (OR = 4.14, 95% CI = 1.24-13.79, p < .001, I2 = 89.67%). Between-study heterogeneity was high. CONCLUSIONS: We found low-quality evidence for positive effects of interventions targeting hand hygiene, with unclear results for interventions targeting face mask use. There was a lack of evidence for most behaviours of interest within this review.