Factors Affecting Influenza Vaccination Rate in Adults with Asthma

Frequency of Asthma Exacerbations and Upper Respiratory Tract Infections Among Adults With Asthma According to Vaccination Status: Does the annual influenza vaccine have a protective effect?

Objectives

Annual influenza vaccinations are recommended for asthma patients to prevent seasonal influenza and influenza-triggered asthma exacerbations. However, data on the beneficial effect of this vaccine on the frequency of asthma exacerbations are conflicting. Therefore, this study aimed to assess the effectiveness of the influenza vaccine in terms of reducing the frequency of asthma-related exacerbations and upper respiratory tract infections among adult patients with asthma.

Methods

This retrospective cohort study was performed from January to December 2018 in Muscat Governorate, Oman. A total of 466 patients attending 9 randomly selected primary health centres in Muscat Governorate were enrolled in the study and followed up for one year post vaccination.

Results

Most of the patients were female (70.6%) and had moderate persistent asthma (42.9%). There were 203 patients (43.6%) in the vaccinated group and 263 patients (56.4%) in the non-vaccinated group. A proportion of patients in each group had allergic rhinitis (28.6% and 25.5%, respectively). The frequency of upper respiratory tract infections over the one-year follow-up period was significantly lower in the vaccinated group than in the non-vaccinated group (37.9% versus 73%; relative risk [RR]: 2.299; 95% confidence interval [CI]: 1.834-2.882; P <0.001); however, there was no significant difference in terms of the frequency of asthma exacerbations (41.9% versus 45.2%; RR: 0.925; 95% CI: 0.750-1.141; P >0.050).

Conclusion

The influenza vaccine significantly reduces the frequency of upper respiratory tract infections over the following year. However, it does not significantly reduce the frequency of asthma exacerbations among Omani adults with asthma. Further studies are recommended to support the protective effect of the vaccine in this regard.

Factors associated with repeated influenza vaccine uptake among aged care staff in an Australian sample from 2017 to 2019

BACKGROUND/AIM

Influenza vaccination is strongly recommended every year for aged care staff to protect themselves and minimise risk of transmission to residents. This study aimed to determine the factors associated with repeated annual influenza vaccine uptake among Australian aged care staff from 2017 to 2019.

METHODS

Demographic, medical and vaccination data collected from the staff, who participated in an observational study from nine aged care facilities under a single provider in Sydney Australia, were analysed retrospectively. Based on the pattern of repeated influenza vaccination from 2017 to 2019, three groups were identified: (1) unvaccinated all three years; (2) vaccinated occasionally(once or twice) over three years; and (3)vaccinated all threeyears. Multinomial logistic regression analysis was performed to better understand the factors associated with the pattern of repeated influenza vaccination.

RESULTS

From a total of 138 staff, between 2017 and 2019, 28.9 % (n = 40) never had a vaccination, while 44.2 % (n = 61) had vaccination occasionally and 26.8 % (n = 37) had vaccination all three years. In the multinomial logistic regression model, those who were<40 years old (OR = 0.57, 95 % CI: 0.19-0.90, p < 0.05) and those who were current smokers (OR = 0.20; 95 % CI: 0.03-0.76, p < 0.05) were less likely to have repeated vaccination for all three years compared to the unvaccinated group. Those who were<40 years old (OR = 0.61; 95 % CI: 0.22-0.68, p < 0.05) and those who were born overseas (OR = 0.50; 95 % CI:0.27-0.69, p < 0.05) were more likely to be vaccinated occasionally compared to the unvaccinated group.

CONCLUSION

The significant predictors of repeated vaccine uptake across the three-year study period among aged care staff were age, smoking status and country of birth (Other vs Australia). Targeted interventions towards the younger age group (<40 years old), smokers and those who were born overseas could improve repeated influenza vaccination uptake in the aged care workforce.

Trends and factors associated with influenza vaccination in subjects with asthma: analysis of the Korea National Health and Nutrition Examination Survey between 2010 and 2019

BACKGROUND

Despite the importance of influenza vaccination, its rates in subjects with asthma are suboptimal, especially in the young population.

METHODS

Among 72,843 adults aged ⩾18 years from the Korea National Health and Nutrition Examination Survey conducted between 2010 and 2019, 1643 with asthma were included. The yearly trends and factors associated with influenza vaccination were analyzed in subjects with asthma. In addition, stratified analyses were performed by age group (<65 versus ⩾65 years).

RESULTS

During the study period, the overall influenza vaccination rate among subjects with asthma fluctuated from 51.0% to 64.3%, with a consistently higher vaccination rate in elderly subjects than in young subjects. Among young subjects with asthma, factors positively associated with influenza vaccination were female sex [adjusted odds ratio (aOR) = 1.66, 95% confidence interval (CI) = 1.11-2.49], current asthma being treated (aOR = 1.69, 95% CI = 1.14-2.50), history of pulmonary tuberculosis (aOR = 2.01, 95% CI = 1.04-3.87), and dyslipidemia (aOR = 1.86, 95% CI = 1.05-3.30). However, unmarried subjects showed an inverse relationship (aOR = 0.50, 95% CI = 0.34-0.75). In elderly subjects, unmarried status (aOR = 0.52, 95% CI = 0.29-0.94), being underweight (aOR = 0.29, 95% CI = 0.09-0.97), and having a low income (aOR = 0.42, 95% CI = 0.18-0.97) were factors negatively associated with influenza vaccination.

CONCLUSION

In the last 10 years, influenza vaccination rates have still been insufficient in subjects with asthma, particularly in young subjects. Considering the factors that are influencing the vaccination rates of young subjects, public policies to increase influenza vaccination rates in subjects with asthma need to be established urgently.