Coverage of Influenza Vaccination among Elderly in South Korea: A Population Based Cross Sectional Analysis of the Season 2004-2005

Factors associated with influenza vaccine coverage among patients with diabetes: Korea National Health and Nutrition Examination Survey 2016-2018

Background

Although the influenza vaccine has been proven to be effective, this common disease has high morbidity and mortality rates. Moreover, adults with diabetes are at a high risk of influenza-mediated morbidity and mortality.

Purpose of the study

With the increasing prevalence of diabetes, influenza is more lethal in diabetics; thus, we aimed to investigate the factors associated with influenza vaccination coverage in patients with diabetes.

Methods

Cross-sectional data were obtained from the Korea National Health and Nutrition Examination Survey (2016–2018). We retrospectively analyzed whether sociodemographic, health-related, and medical factors are associated with influenza vaccination coverage in patients with diabetes. We performed a complex sample logistic regression analysis and estimated the odds ratios (ORs) by adjusting for statistically significant factors.

Results

The number of survey subjects was 18,553. The vaccine coverage rate among patients with diabetes was 60.6%. In the univariate analysis, sex, educational level, smoking, exercise, drinking, marital status, private health insurance, activity limit, economic activity, age, and EuroQol-5 Dimension scores, which were used to assess health-related quality of life, were associated with vaccination coverage. In the multivariate analysis, only age and economic activity were associated with vaccination coverage. The vaccination coverage rate was higher for people who did not undertake economic activities and who were older (OR 1.512 (1.087–2.105), OR 2.212 (1.822–2.686), respectively, p < 0.001).

Conclusion

National interventions involving public health centers are necessary to encourage influenza immunization for patients with diabetes, especially younger patients and those who work or undertake economic activities.

Trends in Infectious Disease Mortality, South Korea, 1983-2015

We used national statistics from 1983-2015 to evaluate trends in mortality caused by infectious diseases in South Korea. Age-standardized mortality from infectious disease decreased from 43.5/100,000 population in 1983 to 16.5/100,000 in 1996, and then increased to 44.6/100,000 in 2015. Tuberculosis was the most common cause of death in 1983 and respiratory tract infections in 2015. We observed a significant decline in infant deaths caused by infectious diseases, but mortality in persons age >65 years increased from 135 deaths/100,000 population in 1996 to 307/100,000 in 2015. The relative inequality indices for respiratory tract infections, sepsis, and tuberculosis tended to increase over time. Although substantial progress has been achieved in terms of infant mortality, death rates from infectious disease has not decreased overall. Elderly populations with lower education levels and subgroups susceptible to respiratory infections and sepsis should be the focus of preventive policies.

Cost effectiveness of influenza vaccination in patients with acute coronary syndrome in Korea

BACKGROUND

Influenza can cause cardiovascular abnormalities by inappropriately activating the coagulation cascade. Therefore, influenza vaccination is important because it decreases the risk of hospitalization for and mortality associated with heart disease. In particular, it reduces the occurrence of major adverse cardiovascular events (MACEs) in acute coronary syndrome (ACS) patients. Our study aimed to estimate the disease burden of MACEs and its related direct and indirect costs in ACS patients.

METHODS

We estimated the direct and indirect cost of MACEs in ACS patients using a probabilistic model and the Health Insurance Review and Assessment (HIRA)-National Patient Sample (NPS) database. The effect of the influenza vaccination on the rate of MACE in ACS patients was determined using a previous systematic review and meta-analysis.

RESULTS

Our study included 682,258 ACS patients obtained from the 2013 NPS database. According to our model, influenza vaccination would prevent 16,514 MACE-related hospitalizations and 2764 premature deaths in Korea per year. The overall reduction in costs would be $86.2 million per year from a societal perspective. Based on the results of sensitivity analysis, most of the estimated values were in the dominant area.

CONCLUSIONS

Our findings show that influenza vaccination in ACS patients is highly cost effective in terms of lowering the cost of hospitalization and premature death due to MACE. Therefore, influenza vaccination is recommended as a means of relieving the clinical and socioeconomic burdens associated with ACS.

Influenza Vaccination Coverage Rate according to the Pulmonary Function of Korean Adults Aged 40 Years and Over: Analysis of the Fifth Korean National Health and Nutrition Examination Survey

Influenza vaccination is an effective strategy to reduce morbidity and mortality, particularly for those who have decreased lung functions. This study was to identify the factors that affect vaccination coverage according to the results of pulmonary function tests depending on the age. In this cross-sectional study, data were obtained from 3,224 adults over the age of 40 who participated in the fifth National Health and Nutrition Examination Survey and underwent pulmonary function testing in 2012. To identify the factors that affect vaccination rate, logistic regression analysis was conducted after dividing the subjects into two groups based on the age of 65. Influenza vaccination coverage of the entire subjects was 45.2%, and 76.8% for those aged 65 and over. The group with abnormal pulmonary function had a higher vaccination rate than the normal group, but any pulmonary dysfunction or history of COPD did not affect the vaccination coverage in the multivariate analysis. The subjects who were 40-64 years-old had higher vaccination coverage when they were less educated or with restricted activity level, received health screenings, and had chronic diseases. Those aged 65 and over had significantly higher vaccination coverage only when they received regular health screenings. Any pulmonary dysfunction or having COPD showed no significant correlation with the vaccination coverage in the Korean adult population.

Influenza and Pneumococcal Vaccine Coverage Rates among Patients Admitted to a Teaching Hospital in South Korea

Background

Influenza and pneumococcal vaccinations can reduce morbidity and mortality especially in the elderly and patients with chronic medical disease. The purpose of this study was to estimate vaccination coverage of these populations in a hospital setting.

Materials and Methods

We conducted a cross-sectional, descriptive study involving adult patients admitted to a 1,000-bed teaching hospital on April 15, 2013. We ascertained the information on whether the patient had received influenza vaccination within a year prior to admission or pneumococcal vaccination by interviewing each patient.

Results

A total of 491 eligible patients aged ≥50 years or with chronic medical illnesses were analyzed. The overall vaccination rate for influenza was 57.2%, and that of pneumococcus was 17.6% among the vaccine-eligible subjects. Influenza/pneumococcal vaccination rates of patients by disease were 62.8%/17.2% for diabetes, 53.3%/15.6% for malignancy, 67.6%/23.5% for chronic pulmonary disease, 66.7%/15.3% for chronic cardiovascular disease, 68.7%/26.9% for chronic renal disease, and 51.2%/18.6% for chronic hepatic disease. Young adult patients with chronic medical conditions were consistently less likely to receive influenza and pneumococcal vaccines irrespective of the underlying disease.

Conclusion

The influenza and pneumococcal vaccine coverage rates among hospitalized patients were low in South Korea. This was especially the case for young adult patients with chronic medical illnesses.

Immunogenicity of influenza vaccine in colorectal cancer patients

Purpose

Although influenza is regarded as a major cause of morbidity and mortality in immunocompromised patients, vaccine coverage remains poor. We evaluated the immunogenicity of influenza vaccines in colorectal cancer patients.

Materials and Methods

In this study, 40 colorectal cancer patients who received an influenza vaccine at the Korea Cancer Center Hospital during the 2009-2010 and 2010-2011 influenza seasons were analyzed. The blood samples were collected at prevaccination and 30 days post vaccination, and antibody titers were measured using the hemagglutination-inhibition tests.

Results

In the 2009-2011 season, the seroprotection rate for H1N1 (94.7%) was significantly higher than that for H3N2 (42.1%) and B (47.3%). The seroconversion rate was 52.6%, 26.3%, and 36.8% for H1N1, H3N2, and B, respectively. Fold increase of geometric mean titer (MFI) was 3.86, 1.49, and 3.33 for H1N1, H3N2, and B, respectively. In the 2010-2011 season, the seroprotection rate for H1N1 (57.1%) was significantly higher than that for H3N2 (52.4%) and B (38.1%). The seroconversion rate was 52.4%, 47.6% and 33.3% for H1N1, H3N2, and B, respectively. MFI was 12.29, 3.62 and 4.27 for H1N1, H3N2, and B, respectively.

Conclusion

Our study cohort showed an acceptable immune response to an influenza vaccine without significant adverse effects, supporting the recommendation for annual influenza vaccination in colorectal cancer patients.

Influenza vaccination among adults 65 years or older: a 2009-2010 community health survey in the Honam region of Korea

The present study examined the rates and related factors for influenza vaccination among the elderly Korean population during the 2008/09 influenza seasons. We obtained data for 6,391 adults aged 65 years or older from Community Health Surveys conducted in 2009 and 2010 in 13 communities in the Honam region of Korea. A multiple logistic regression analysis was used to identify the factors associated with self-reported influenza vaccinations. In this elderly population, 81.7% reported to having received an influenza vaccination in the past year. The main contributing factors were older age, lower economic status, lower educational level, married, non-smoking, regular alcohol consumption, regular walking exercise, receiving a health check-up during the past two years, not stressed, and having comorbid conditions. The influenza vaccination coverage rate among elderly Koreans was relatively high, but improvements in vaccination rates are required.