Assessment of the factors influencing primary care physicians’ approach to vaccination of adult risk groups in Istanbul, Turkey

Introduction

Vaccination is a primary method for preventing infectious diseases. The Advisory Committee on Immunization Practices (ACIP) in the USA provides immunization recommendations for all age groups based on updated annual data (Kim, Riley & Hunter, 2018). Wide range of countries, including Turkey, refer to these recommendations to determine vaccination policies. Although childhood immunization programs are successfully implemented in the majority of the world (Murthy et al., 2017), adult immunization is still an important issue due to various reasons such as unwillingness to get vaccinated, concerns about the efficiency and side effects of vaccines, and inadequate knowledge about adult immunization and failure to recommend the necessary vaccines by the physicians (Lutz et al., 2018; Srivastav et al., 2018). In fact, adult vaccination has a vital role in the management of chronic diseases and immune deficiency; also it has a very important role in fighting against specific diseases which have increased the likelihood in some regions. Nevertheless, increasing the rate of adult immunization remains an important problem worldwide.

Primary care physicians (PCPs) play a critical role in childhood immunization and are also responsible for carrying out a targeted approach to immunization in adult patients (Campos-Outcalt et al., 2010; Gai & Gu, 2014; Leask, 2009). Therefore, PCPs’ attitude is vital to reach a desired rate of adult vaccination. According to the national vaccination schedule in Turkey, childhood vaccination rate in 2017 was 96%; however, data is limited in regard to national adult vaccination rates (Bora-Başara et al., 2018). Because there is no official data on the number of patients in risk groups, the number of healthy individuals aged 65 and over, and vaccination coverage rate among these groups; there is no clarified data on how to deal with the vaccination requirements of adult patients. Additionally, vaccination rates among risk groups are reportedly rather low in Turkey; however, these data have been obtained from various single-center studies (Table 1).

In Turkey, the major problem in adult immunization is the lack of a national health policy which is caused by the assumption that its economic burden would become a drain on the national budget (EKMUD Adult Immunization Working Group, 2009). Until recently, based on economic and financial reasons, adult immunization was overlooked in Turkey, except in certain special conditions and individual demands.

With this background in mind, we aimed to evaluate the factors influencing PCPs’ attitude to adult vaccination in the specified risk group. The risk group consists of three main categories: the patients older than 65, the patients suffer from the chronic obstructive pulmonary disease (COPD) or chronic liver disease, and the patients of those had splenectomy before.

We aimed to answer four main questions in our study: (1) What is the vaccination rate of physicians themselves? (2) What are the PCP’s rates of vaccination recommendation/prescription to adult patients in risk groups? (3) Is there any difference between PCPs that are vaccinated and those that are not, in terms of recommending vaccines to their patients? (4) What are the factors that are associated with the prescription of vaccines among PCPs? Since we aimed to evaluate the attitude of the physicians, both recommendations and prescriptions were considered as a positive attitude concerning adult vaccination.

Materials and Methods

Results

A total of 221 PCPs that responded to the survey were included in the study. The response rate was very low (14.7%). According to gender, 123 of 221 subjects were female and 98 were male. In regard to age, 61.5% (n = 136) of the PCPs were younger than 40, and 99 were in the 31–40 age group. The number of PCPs with ≤10 years of professional experience was 72% (n = 161). Sociodemographic characteristics of the participants are shown in Table 1; 89% of the participants were working at city centers and 95% (n = 210) had over 3,000 registered patients. The mean number of daily visits was 35 ± 12.2 for patients aged >18 years; 15 ± 8.9 for patients aged >65 years; and 15 ± 10.4 for the risk groups. Among the participants, 72.4% (n = 160/221) were following the regulations of the Ministry of Health to keep up to date with current information on adult immunization. The percentage of PCPs that recommended tetanus, influenza, and HBV vaccinations to patients aged ≥65 years (in accordance with Ministry of Health recommendations) were 65.6%, 71.2%, and 62.5%, respectively.

Since the response rate was far lower than expected, a sufficient amount of data concerning some factors and some vaccine types could not be gathered. Nevertheless, the main goals of the study were achieved. Findings concerning our four main questions are given below:

Discussion

In this study, we found that younger PCPs are more intent on prescribing adult vaccines to patients in certain risk groups including those with COPD, chronic liver disease, and prior splenectomy. We also found that PCPs with lower experience were prescribing adult vaccines at a slightly higher proportion than their counterparts with higher experience.

Adult immunization is strongly recommended in patients with several diseases which alter immunity, including DM, COPD, and chronic liver diseases. According to the Global Initiative for Chronic Obstructive Lung Disease 2011 COPD guidelines, both influenza and pneumococcal vaccines are suggested for all patients with COPD in order to lower exacerbation rates and associated mortality (Vestbo et al., 2013). In addition, international guidelines recommend HAV and HBV vaccinations for disease prevention in patients with chronic liver diseases (Fiore, Wasley & Bell, 2006). Vaccination for influenza, pneumococcus, and hepatitis B is also recommended in patients with DM. In patients with prior splenectomy, vaccination against S. pneumonia, N. meningitidis, H. influenza type b, and influenza virus are strongly recommended as these patients are vulnerable to invasive infections caused by encapsulated bacteria (Bonanni et al., 2017).

Healthcare professionals are also considered to be at high risk of vaccine-preventable diseases, particularly those caused by blood- and air-borne pathogens. The vaccines recommended for healthcare professionals include influenza, measles-mumps-rubella, hepatitis B, varicella, Td, meningococcal, and hepatitis A (Kim, Riley & Hunter, 2018). In the current study, the percentage of participants who had had vaccinations for HBV, tetanus, and influenza were comparable to global averages reported in various studies (Castilla et al., 2013; Opstelten et al., 2008; Pulcini et al., 2013; Semaille et al., 2006). However, there are countries in which physician vaccination rates have reached desired levels (Cowan et al., 2006; Paya et al., 2013) which shows that there is still much that can be done to increase the immunization awareness of PCPs. In our study, female PCPs were found to have significantly higher rates of influenza vaccination and PCPs aged 31–40 years had higher immunization rates for all three vaccines. In terms of recommending vaccines to patients, gender was found to have no effect, while PCPs aged 31–40 were found to be more likely to recommend influenza, HBV, and meningococcal vaccines to patients in respective risk groups.

In the current study, PCPs with lower age (<40) and lesser experience (<10 years) were more likely to prescribe adult vaccines in certain risk groups. However, in a previous study, Asma et al. (2016) reported that vaccination compliance was higher in PCPs with increased age and higher experience. Another study investigating healthcare professionals’ attitude to vaccination revealed that participants with higher experience were more likely to get vaccinated (Ali et al., 2018). Although our findings are conflicting with the results of many previous studies, some possible explanations could be derived regarding this controversy.

First of all, there is limited data investigating the role of age and occupational experience on vaccine prescription rates. As mentioned above, up-to-date knowledge is of great importance to understand the preventative role of vaccines in the adult population. However, physicians with higher age and experience almost always have higher patient counts and are probably unable to follow current scientific data on immunization due to time limitations, while younger PCPs with relatively less experience are more up to date, which may be due to their more recent medical school training. In our study, most of the participants stated that they were following the Health Ministry’s regulations as the sole resource of information on vaccination, which may indicate the absence of effort or facilities for reaching more current data on adult vaccination. In addition, lack of motivation in terms of keeping up to date with medical changes may also be a factor negatively impacting the knowledge of PCPs, as there is currently no “board examination” aimed at regularly evaluating the primary healthcare knowledge of PCPs. Such an examination—with a clear and concise approach—may motivate physicians to follow recent developments and guidelines other than those proposed by the Ministry of Health. Under these circumstances—in which PCPs do not, or cannot keep up to date with current guidelines—information gained at medical school and Ministry of Health guidelines become the only source for their future occupational practice, which constitutes an answer for the question why younger and relatively less-experienced PCPs more frequently prescribe adult vaccines. However, many other factors may contribute to the difference observed in this study. Our results by no means prove these assumptions. Future studies would benefit from evaluating other parameters associated with primary care in order to come to an accurate conclusion on this matter.

We also evaluated whether there was a relationship between personal vaccination and prescription of vaccines to patients in risk groups. Although adult vaccination is crucial especially in certain risk groups, the importance of adult vaccination might be underestimated by healthcare professionals, particularly PCPs who are always in communication with their registered populations and primarily responsible for vaccination (Albano et al., 2014; Yassi et al., 1994). A systematic review written by Wilson et al. (2015) reported that, lower recommendation by healthcare workers, reservations about vaccine safety, belief that vaccines are not needed or effective, and low knowledge about vaccines and their cost were the most prominent factors influencing low vaccination rates. A survey study conducted in Australia on adult patients admitted to the emergency department reported that 84.6% of those who received vaccinations trusted their family physicians and considered the vaccines that they recommended (Sandhofer et al., 2017). Although conflicting results exist, a nationwide survey conducted in Germany, which showed that although a high proportion of the healthcare workers were influenza vaccinated, many of them had not recommended or prescribed influenza vaccine to their patients (Wortberg et al., 2009). Furthermore, several studies have shown that PCPs’ vaccine recommendations to patients are significantly associated with their own immunization attitudes (Godoy et al., 2015; Nichol & Zimmerman, 2001; Poland, 2010; Verger et al., 2012). In a recent study carried out in Italy, investigators have shown a clear decline in the frequency of health care workers’ vaccination status with increasing age—with lowest rates in health care workers aged between 51 and 60 years (Gilardi et al., 2018). Therefore, we believe that the knowledge of a PCP and their subsequent approach to patients are the major factors that influence the vaccination of adults. In the light of our findings and data obtained from the literature, we believe that increasing the awareness of PCPs in terms of vaccine effectiveness and indications may contribute significantly to the immunization of adults in risk groups.

Conclusion

Our study revealed that younger PCPs (especially those aged between 31 and 40 years) and those with relatively less experience were more likely to prescribe adult vaccines, especially in certain risk groups that were predisposed to vaccine-preventable diseases. Our results indirectly emphasized the role of physicians’ knowledge level on immunization. According to the results of the present study, we suggest that educational programs should be carried out for PCPs aged over 40 years and those with more than 10 years of occupational experience, in order to improve their knowledge and understanding of adult immunization.

Supplemental Information