ABSTRACT

Objectives

In recent years, especially with the Coronavirus Disease of 2019 (COVID-19) pandemic, the use of herbal products for various health problems has been increasing worldwide. This study aimed to determine the frequency of herbal product/dietary supplement use, the most used products, and the factors affecting the use of these products in patients who applied to the Chest Diseases Clinic.

Materials and Methods

This descriptive survey study was conducted at Chest Diseases Clinic using a face-to-face interview technique. Adult individuals with subacute respiratory complaints for > 3 weeks or a diagnosis of chronic chest disease were included in the study. The questionnaire form included questions about personal characteristics, data related to disease and treatment, use of herbal products/dietary supplements, and attitudes toward these products. A total of 444 participants with all the data included in the study. Descriptive statistics, chi-square, and binary logistic regression tests were used.

Results

It was determined that 49.3% of the participants used herbal products/dietary supplements, and the most frequently used products were honey, linden, ginger, lemon, and carob. According to the results of the binary logistic regression test, it was determined that patients over 60 years old [odds ratio (OR)= 2.0, 95% confidence interval (Cl): 1.1-3.8, p= 0.042], those with a high education level (OR= 2.0, 95% Cl: 1.1-3.6, p= 0.018), those who live in urban (OR= 1.8, 95% Cl: 1.1-3.0, p= 0.018), and those with a diagnosis of post-COVID syndrome (OR= 2.7, 95%, Cl: 1.3-5.5, p= 0.007) are more likely to use these products. It was determined that 57.9% of the participants used these products to relieve the symptoms of the disease.

Conclusion

Considering the high probability of using these products in patients with respiratory tract disease, it is essential for public health that health professionals question the use of these products and provide counseling on this issue.

INTRODUCTION

Respiratory diseases, particularly asthma, chronic obstructive pulmonary disease (COPD), and lung cancer, affect many people around the world. According to World Health Organization data, COPD, lower respiratory tract infections, and lung cancer were determined as three of the ten diseases that caused the most deaths in 2019.¹ “Coronavirus Disease of 2019” (COVID-19), which has emerged recently and caused a pandemic, significantly affects the respiratory system. Post-COVID syndrome is a condition in which there are new, recurrent, or ongoing symptoms and clinical findings after an acute infection with COVID-19. COVID-19 and post-COVID syndrome have increased morbidity and mortality rates.²

With important developments in treating respiratory diseases in recent years, these diseases are controlled, and morbidity rates are decreasing.³ However, there is a tendency for different searches in patients due to the increase in the incidence of diseases, the inability to fully recover with known treatment methods, drug side effects, dissatisfaction with treatment and health services, and fear and anxiety caused by the COVID-19 pandemic experienced in recent years.⁴^,⁵ In this context, traditional and complementary treatment methods such as medicinal plants, acupuncture, homeopathy, hypnotherapy, aromatherapy, breathing, and relaxation techniques are used for respiratory system disorders.⁶^,⁷ Plants have been used for centuries for purposes such as controlling, treating, and preventing diseases.⁸In Türkiye, herbal products are available in the form of finished products as traditional herbal medicinal products and herbal medicines approved by the Ministry of Health, and dietary supplements approved by the Ministry of Agriculture and Forestry, apart from forms such as raw drugs and teas.⁹

There are studies evaluating the use of herbal products/dietary supplements in people with respiratory disorders.^10-13 The use of herbal products was found to be 61.8% in a study conducted in participants with respiratory tract diseases in Germany.⁸ In another study conducted with 274 students in Saudi Arabia, it was determined that 62.7% of the participants used herbal products for the prevention of respiratory tract infections and 48.5% of them occasionally used herbal products when they had an illness related to respiratory tract infections.⁵ In studies conducted in Türkiye, the frequency of use of herbal products and supplements in patients with various respiratory diseases (asthma, COPD, pharyngitis, cough, flu-cold, rhinitis, tonsillitis, and respiratory tract infections) varies between 64.5% and 90.8%.¹³^,¹⁴

While there were studies investigating the use of herbal products in patients with asthma, COPD, allergic rhinitis, and lung cancer, no study was found in patients with pulmonary embolism, interstitial lung diseases, respiratory symptoms, and post-COVID syndrome. This study aimed to determine the frequency of herbal products/dietary supplement use, the most used products, the factors affecting the use of these products, and the attitudes of patients toward these products in patients who applied to the Chest Diseases Clinic.

MATERIALS AND METHODS

Study design and sample size

This descriptive study was conducted at Chest Diseases Clinic between 15.11.2021 and 01.05.2022. Adult individuals (≥ 18 years of age) with subacute respiratory complaints for more than 3 weeks or a diagnosis of chronic chest disease who agreed to participate in this study were included in the study. The questionnaire form was administered to the participants using the face-to-face questionnaire technique. Participants were informed about the content and purpose of the study, and their consent was obtained. The interview with each patient lasted approximately 15 minutes.

Questionnaire form

The questionnaire form was created by examining the literature and consists of four parts: personal characteristics, disease and treatment characteristics, use of herbal products/dietary supplements, and attitudes toward herbal products/dietary supplements.

Personal characteristics included age, gender, education level, place of residence, having a job, self-reported general health status, and body mass index (BMI) (kg/m²). BMI was calculated by dividing weight (kg) by the square of height (m). In the next section, chest-related diseases/symptoms, the duration of diagnosis (week, month, year), the medicines used, whether there is a problem with the treatment, and self-reported satisfaction with the treatment were evaluated. Diseases/symptoms were evaluated in four categories: post-COVID syndrome, respiratory airway and allergic diseases (asthma, COPD, bronchiectasis and allergic rhinitis), respiratory symptoms (cough, dyspnea, and chest pain), and other diseases group (pulmonary embolism, interstitial lung diseases, lung cancer, and structural disorders in the lung). The Global Initiative for Asthma symptom control assessment algorithm-scale was used to determine the level of symptom control in asthma patients.¹⁵ According to the results of the pulmonary function test in diseases involving the airways, when the forced expiratory volume 1 second (FEV1)/forced vital capacity (FVC) ratio is below 80%, it is classified as an obstructive disease, and when the ratio is normal and the FVC is below 80%, it is classified as a restrictive disease.¹⁶

In the section on herbal products/dietary supplements use, there are questions such as the use of herbal products/dietary supplements, the products used, how these products are used, the reason for use, sources of information about these products, place of supply, side effects, and whether the information about the use was given to the doctor. All plant-derived products, such as raw drugs, teas, herbal medicinal products, dietary supplements, and herbal preparations were evaluated. The contents of the preparations containing herbal products/dietary supplements were investigated and the mixtures were evaluated separately. In the determination of the products used, the statements of the participants were taken as the basis, and no species identification was made. In the last section, there are six questions that evaluate the opinions of all patients toward herbal products/dietary supplements. Before the data were collected, a pre-test was conducted with 20 participants. The questionnaire was finalized according to the feedback.

Ethics committee approval of the study was received from the Karadeniz Technical University Faculty of Medicine, Scientific Research Ethics Committee (date: 24.11.2021, number: 24237859-856, protocol number: 2021/329).

Statistical analysis

The IBM SPSS 23.0 (SPSS Inc., Chicago, IL, USA) statistical package program was used for data analysis. Descriptive statistics were presented as number (n), percent (%), mean, standard deviation (SD), minimum (min.), and maximum (max.) values. The chi-square test was used to compare categorical variables.

Multivariate analyses of the factors affecting the use of herbal products were performed using the logistic regression test. The model was created using the enter method. The independent variables included in the model were age, gender, education level, place of residence, working a job, general health status, BMI, diagnosis/symptoms that are the reason for application, duration of diagnosis/symptoms, and regular use of medicines. Results are presented with odds ratio (OR) and 95% confidence interval (CI) values. Hosmer-Lemeshow test results and Nagelkerke R² values were calculated. The statistical significance level was set as p < 0.05.

RESULTS

The mean age of the participants was 50.7 ± 17.6 years (min.= 18, max.= 90). 324 (73.0%) of the participants were women. The personal characteristics of the participants and their use of herbal products/dietary supplements according to these characteristics are presented in Table 1. It was determined that 219 (49.3%) participants used herbal products/dietary supplements. The most used products were honey (n= 126, 57.5%), linden (n= 74, 33.8%), ginger (n= 60, 27.4%), lemon (n= 53, 24.2%), and carob (n= 24, 10.9%). These products were used in different ways: directly, as an infusion/decoction, alone, or in combination with other herbs, mostly internally. For example, honey was consumed directly or mixed with different herbs such as ginger or turmeric, linden as a decoction, lemon directly as an infusion or added to tea, and carob as molasses. Herbal products and dietary supplements used by the participants are presented in Table 2.

Gender, general health status, and BMI were not associated with herbal product use. Seventy-one (55.0%) patients between the ages of 18 and 40, 73 (42.0%) patients between the ages of 41 and 60, and 75 (53.2%) patients over the age of 60 were using herbal products/dietary supplements (p= 0.043). Urban residence (p= 0.003), high school and above education status (p= 0.004), and having a job (p= 0.039) were associated with a higher frequency of herbal products/dietary supplements use (Table 1).

Of the participants, 160 (36.0%) presented with respiratory airway diseases and allergic diseases (22.5% asthma, 4.7% COPD, 1.8% bronchiectasis, 7.0% allergic rhinitis), 124 (27.9%) with respiratory symptoms (14.2% cough, 8.3% dyspnea, 5.4% chest pain), 78 (17.6%) with ongoing complaints after COVID, and 82 (18.5%) with other diseases (5.9% interstitial lung diseases, 4.7% lung cancer, 4.5% pulmonary embolism, 4.5% structural disorders in the lung). The mean duration of individuals’ diagnoses/symptoms was 3.68 ± 5.85 years. There was no significant association between the use of herbal products/dietary supplements and the duration of the disease/symptoms (p= 0.788), medicine use (p= 0.290), regular use of medicines (p= 0.056), treatment satisfaction (p= 0.942), treatment problems (p= 0.492), and FEV1/FVC ratio (p= 1.000). Forty-nine (62.8%) people with post-COVID syndrome, 77 (48.1%) people with respiratory airway diseases and allergic diseases, 62 (50.0%) people with respiratory symptoms, and 31 (37.8%) people with other diseases were using herbal products/dietary supplements (p= 0.017). It was determined that these products were used more in asthma patients than in well-controlled patients with inadequate and uncontrolled symptoms (p= 0.034). The characteristics of the participants regarding the disease/symptom and treatment and the use of herbal products/dietary supplements according to these characteristics are shown in Table 3.

According to multivariate analysis, the use of herbal products/dietary supplements was not associated with gender, job status, general health status, BMI, duration of diagnosis/symptoms, and regular use of medicines. Herbal products/dietary supplements use was higher in patients who were older than 60 years (OR= 2.0; 95% CI: 1.1-3.8, p= 0.042), had high school or higher education (OR= 2.0; 95% CI: 1.1-3.6, p= 0.018), and urban resident (OR= 1.8; 95% CI: 1.1-3.0, p= 0.018). Participants with post-COVID syndrome were more likely to use these products than those with other diseases (OR= 2.7; 95% CI: 1.3-5.5, p= 0.007). The results of the logistic regression analysis regarding the factors affecting the use of herbal products/dietary supplements by the participants are presented in Table 4.

One hundred seventeen (53.4%) of the participants stated the source of information about the products they used as friends/relatives, and 82 (37.4%) of them obtained these products by collecting them from nature. One hundred sixty five (73.3%) of the participants who used herbal products/dietary supplements thought that the products they used were beneficial. One hundred and sixty-one (70.9%) did not inform their doctor about the products they used, and 186 (81.9%) wanted to get information about these products from healthcare professionals. The reasons for the participants’ use of herbal products/dietary supplements, the sources of information about these products, the places provided, and the benefits of these products are presented in Table 5.

The opinions of the participants regarding herbal products/dietary supplements are presented in Table 6.

During the study, 459 patients were reached. The collected data were checked by the researchers, and 444 participants without missing data were included in the analyses.

DISCUSSION

In this study, the use of herbal products/dietary supplements in patients who applied to the Chest Diseases Clinic in a tertiary health institution and the factors affecting their use were evaluated.

The frequency of use of herbal products/dietary supplements for all participants was 49.3%, 62.8% in post-COVID syndrome, 50.0% in patients with subacute/chronic respiratory symptoms, 48.1% in respiratory airway diseases and allergic diseases, and 37.8% in other diseases. In studies conducted in Germany and the United States of America, it was reported that 61.8% and 41.4% of the participants, respectively, used herbal products/dietary supplements for respiratory disorders.⁸^,¹⁷ In studies conducted with participants with respiratory system diseases in Türkiye, the frequency of use was found to be between 64.5% and 90.8%.¹³^,¹⁴ Studies have mostly focused on certain disease groups such as asthma, COPD, allergic diseases, and lung cancer. Studies have shown that the frequency of use of herbal products/dietary supplements varies between 28.8% and 70.1% in COPD patients, 7.8% and 60% in allergic rhinitis patients, and 24.7% and 48.1% in lung cancer patients.¹¹^,¹²^,^18-22 There is no study investigating the use of herbal products in patients with post-COVID syndrome. In a study conducted by telephone with COVID-19 patients in a quarantine center in India during the COVID-19 pandemic, it was found that 25.8% of patients applied traditional treatment methods both during and after treatment.²³ In studies conducted in the community during the pandemic period, it has been observed that the frequency of use of herbal products/dietary supplements varies between 18% and 64%.²⁴^,²⁵ According to the data obtained from this study, the frequency of herbal product/dietary supplement use is high and similar to the data in the literature.

When the use of herbal products/dietary supplements was evaluated according to sociodemographic and personal characteristics, a significant relationship was found between age, education level, and place of residence. In studies conducted during the COVID-19 pandemic, it has been shown that the use of these products increases with age.²⁶^,²⁷ The reason for this may be the increase in the incidence of chronic diseases with increasing age. In most of the studies conducted on patients with asthma, allergic rhinitis, lung cancer, and during the COVID period, it was determined that the use of these products increased as the level of education increased.¹⁴^,¹⁹^,²²^,²⁸^,²⁹ The data obtained in our study are compatible with the literature findings. It has been reported that the use of herbal products/dietary supplements is higher among individuals with chronic diseases in Thailand, those living in rural areas, and those living in urban areas among participants with respiratory system diseases in Türkiye.¹³^,³⁰ In our study, similar results were found in a study conducted in Türkiye.

A significant correlation was found between the use of herbal products/dietary supplements by the participants, the diagnosis, and the level of asthma symptom control (in asthma patients). Previous studies have determined that there is a positive relationship between the use of herbal products and the diagnosis of asthma.¹²^,²⁰^,³⁰ In this study, it was found that the use of herbal products/dietary supplements was higher in asthma patients with inadequately controlled and uncontrolled symptoms than in patients with controlled symptoms. Similar to our findings, a significant relationship was found between the inability to control asthma symptoms and the use of different traditional methods in studies conducted in Canada and England. The use of herbal products was one of the commonly used methods.³¹^,³² During the COVID-19 pandemic period, the inability to determine the treatment protocol to be applied, especially at the beginning of the pandemic, and the long duration of medicine and vaccine studies have led to an increase in the tendency of society to use these products. In our study, a higher frequency of use was found in patients with post-COVID syndrome compared with the other disease groups. This may be due to the uncertainty caused by the pandemic process and the fact that patients turn to these products to eliminate the long-term effects of COVID-19. In studies conducted during previous pandemics, it has been reported that the tendency to traditional and complementary therapies has increased among people, and the use of herbal products has been preferred primarily.³³

In this study, the majority of the participants who used herbal products/dietary supplements stated that they found the products beneficial. The findings in the literature support our study, and it has been reported that the perceived effectiveness of these products is high.¹²^,¹⁹^,²⁰^,³⁰ In a study conducted with patients with respiratory system diseases in Türkiye, it was reported that 87.5% of patients using herbal products stated that they benefited from the products they used, and 90% of them recommended these products to others.¹³ In our study, the main reasons for the participants to use these products were to relieve symptoms and strengthen the immune system. In a study conducted with university students in Saudi Arabia, 55.5% of the participants used herbal products to prevent and control respiratory tract infections and strengthen the immune system.⁵

Information on herbal products and dietary supplements can be obtained from many sources. Obtaining information from scientific sources or healthcare professionals is important for public health. As in this study, in previous studies, participants’ sources of information about these products were mostly friends and family/relatives.²²^,²⁸^,³⁴ Television/media/newspaper, internet/social media, and herbalists, although to a lesser extent, doctors, pharmacists, and other health personnel are also expressed as sources of information.¹⁹^,²⁰^,²⁹ In a study conducted in Germany, individuals who used herbal products in the last 12 months declared the internet 68.2%, pharmacists 54.2%, and family members 45.6% declared the internet as their source of information.⁸

In this study, it was determined that 70.9% of the participants who used herbal products/dietary supplements did not inform their doctor about this issue, and 81.9% wanted to obtain information about these products from healthcare professionals. In the literature, some studies conducted with asthma and COPD patients found that more than half of the individuals did not inform their doctor or other healthcare professionals.¹⁸^,²⁰^,³³^,³⁴ In some studies, contrary to these findings, it has been determined that individuals should inform doctors before or while using these products.²⁸^,³⁵ It is important for the progress of treatment and public health that healthcare professionals, especially doctors and pharmacists, question the use of natural products by patients and raise awareness on this issue.

Although the regulation of herbal products/dietary supplements varies according to country or region, these products are available in the market with or without a prescription because of the differences in the legislation of herbal products/dietary supplements in Türkiye. In a study conducted in Thailand, it was determined that patients mostly collect the products they use from nature and also obtain them from herbal shops and pharmacies.³⁰ In Türkiye, it has been determined that the places of supply for products of natural origin are mostly herbal shops or markets.³⁶ In this study, similar to the literature, it was determined that the participants collected herbal products/dietary supplements from nature and obtained them from herbal shops and markets. In the Black Sea Region, most of the individuals living in urban areas as well as those living in rural areas have a connection with the village and live in harmony with nature. Therefore, it is expected that these products will mostly be collected from nature.

Due to the increasing demand and use of naturally sourced products, there are also quality, efficacy, and reliability problems related to these products. Herbal products contain a large number and varying amounts of secondary metabolites, which are responsible for their clinical effects and show pharmacological activity. The type and amount of secondary metabolites vary according to the way the plant is collected, harvest time, drying, storage, and processing methods. In addition, it is possible that the desired quality product is not obtained because of adulteration, contamination, wrong plant identification, or labeling with other plants or active substances.³⁷

When the attitudes of the participants toward herbal products/dietary supplements were evaluated, it was determined that the majority of them thought that these products supported treatment, similar to the literature.³⁸ In addition, it can be said that awareness of herb-drug interactions does not need to be at a sufficient level.

This research was conducted during the COVID-19 pandemic. This study investigates the use of herbal products/dietary supplements in individuals with respiratory disease (including asthma, COPD, lung cancer, as well as post-COVID syndrome, interstitial lung diseases, and pulmonary embolism) more comprehensively than studies in the literature, and it is thought to provide important scientific data.

Study limitations

An equal number of patients could not be reached in the groups determined by disease prevalence. Because of the design of the study, the data obtained may not be generalizable to the population.

CONCLUSION

According to our research results, approximately half of the patients with respiratory diseases use herbal products/dietary supplements at a high frequency. The use of these products by patients varies in terms of sociodemographic and disease-related characteristics. The fact that patients with post-COVID syndrome use more herbal products/dietary supplements than other disease groups in this study shows that patients primarily resort to these products in an unknown situation. Considering the information sources and places of supply of the participants about these products, the quality of the products should be increased and they should be controlled by the health authorities to prevent the problems caused by the use of irrational herbal products. It is noteworthy that the majority of patients who use herbal products/dietary supplements do not inform their doctors about this. It is important for healthcare professionals to question the use of herbal products by patients and to provide counseling on this subject to prevent possible adverse effects and herb-drug interactions.

Ethics

Ethics Committee Approval: Ethics committee approval of the study was received from the Karadeniz Technical University Faculty of Medicine, Scientific Research Ethics Committee (date: 24.11.2021, number: 24237859-856, protocol number: 2021/329).

Informed Consent: Participants were informed about the content and purpose of the study, and their consent was obtained.

Authorship Contributions

Concept: T.S., U.Ö., Y.B., Design: T.S., U.Ö., Y.B., Data Collection or Processing: T.S., U.Ö., Y.B., T.Ö., A.K.A, Analysis or Interpretation: T.S., A.K.A., Literature Search: T.S., A.K.A., Writing: T.S., U.Ö., Y.B., T.Ö., G.R., A.K.A.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.

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Evaluation of Herbal Products and Dietary Supplements Use in Patients with Respiratory Diseases Applied to Tertiary Health Institution