1. Introduction
Coronary artery disease (CAD) is the leading cause of death worldwide, responsible for approximately 16.6% of total deaths in 2016 [
1]. Ever since it was first performed in 1977, percutaneous coronary intervention (PCI) has evolved into a widely performed medical procedure in the setting of acute and chronic coronary syndromes [
2,
3]. During recent years, PCI has advanced at a tremendous pace with the rapid development of new technologies [
4] and techniques, including the introduction of drug-eluting stents which lower the chances of restenosis [
5].
Annually, PCI is a treatment modality for more than 1 million in the United States [
2]. In China, more than 300,000 procedures were performed in 2011, an 18-fold increase compared to 2001 [
6], while in India, PCIs are growing at the rate of 14% [
5]. In Denmark, approximately 9000 patients are treated annually with PCI, of whom 2500 are less than 65 years old [
7]. In Greece, PCI is the preferable treatment option for patients with ST-elevation myocardial infarction in PCI hospitals [
8]. However, there are several geographic variations in terms of the organization, operation, management, sustainability and utilization of data collected for PCI registries [
1].
The main indication for PCI is angina relief and improvement in the quality of life (QoL) [
9]. Interestingly, QoL has become an important outcome measure, since most medical treatments are currently not evaluated only in terms of clinical or biomarker benefits. From a clinical perspective, the measurement of QoL provides essential information to health professionals when planning patient-centered practices. Moreover, QoL is monitoring the performance of clinical care, improving safety and outcomes, thus contributing to treatment cost reduction [
10,
11]. Furthermore, QoL provides the basis for comparing different treatment options, such as the choice of vascular access site and determining predictors of health benefits [
12].
From a practical perspective, data exploring QoL in the field of PCI are useful in developing cost-effective strategies or self-care educational programs to maintain optimal benefits of this minimally invasive procedure. QoL measurements may help health care professionals to motivate beneficial changes in patients’ lifestyles or health behaviors.
Therefore, the aim of this study was to explore QoL levels pre-PCI, 6 and 12 months after PCI, as well as the factors associated with QoL in the pre-PCI phase.
2. Materials and Methods
2.1. Design, Setting and Period of the Study
In this cross sectional study, 100 patients (69 men and 31 women) who underwent PCI in a public hospital during the period of 2021 to 2022 were enrolled. Participants were selected using the method of convenience sampling. Of the 110 individuals who were on the initial list, 5 patients did not consent to complete the questionnaire and 5 refused to participate after 6 months. Therefore, the data of 100 individuals were analyzed.
2.2. Inclusion and Exclusion Criteria of the Sample
Criteria for patients’ inclusion in the study were as follows: (i) age above 18 years; (ii) PCI with drug-eluding stents; (iii) ability to write, read and understand the Greek language; and (iv) ability to read and sign the informed consent form. The exclusion criteria were patients: (i) with a history of mental illness; (ii) visiting clinics to treat some other co-morbidity; (iii) with cognitive disorders and sight or hearing problems; and (iv) with a restenosis in the period under exploration.
2.3. Data Collection and Procedure
Data included three measurements: (a) baseline, period up to 1 week before PCI, (b) 6 months after PCI, and (c) 12 months after PCI. The collection of data was performed using the method of interviewing to complete the present research instrument which was specially designed for the purposes of the study. Patients that agreed to participate in the study were invited to a private office room to guarantee their privacy. The QoL measurements at 6 and 12 months were conducted by interview at the hospital when patients had completed their scheduled follow-up. The process of filling out the research instrument lasted approximately between 20 and 30 min.
2.4. Research Instrument
The research instrument included patients’ characteristics and QoL assessment using the scale “SF-36 Health Survey (SF-36)”.
Regarding patients’ demographic, the following characteristics were recorded: gender, age, marital status, educational level, occupation, residency and number of children. In terms of clinical characteristics, the following were recorded: type of PCI, family history of CAD, comorbidities, body mass index (BMI), fat and sodium intake, frequency of exercise, smoking and drinking alcohol.
The SF-36, created by Ware and colleagues in 1993, assesses physical and mental health. It consists of 36 questions comprising 8 dimensions: physical functioning, role-physical, role-emotional, energy/fatigue, emotional well-being, social functioning, bodily pain and general health. Respondents have the option to answer each question on Likert-type scales. The scores assigned to the questions are summed separately for the questions assessing the 8 dimensions. Higher score values indicate a better QoL [
13].
2.5. Ethical Considerations
The present study was approved by the Research Committee of the public hospital and according to the ethical standards of the Declaration of Helsinki (1989) of the World Medical Association. Patients who met the entry criteria were informed by the researcher for the purposes of this study. All patients participated in the study after they had given their written consent. Data collection guaranteed anonymity and confidentiality. All subjects had been informed of their rights to refuse or discontinue participation in the study, Data confidentiality and personal data policy were also respected.
2.6. Statistical Analysis
Categorical data are presented with absolute and relative (%) frequencies, while continuous data are presented with the mean, standard deviation, median and interquartile range, where appropriate. The normality of quantitative data was tested with the Kolmogorov–Smirnov test and graphically with histograms. Non-parametric Mann–Whitney and Kruskal–Wallis tests were used to test for an association between QoL and patient characteristics. In addition, multiple linear regression was performed to assess the effect of characteristics on patients’ QoL, adjusting for potential confounders. Results are presented as β-regression coefficients and 95% confidence intervals (95% CI). To test for a trend in QoL scores over time (6 and 12 months after PCI), an ANOVA model for repeated measures was applied, checking for statistically significant effects in the interaction between time and patient characteristics. The observed significance level of 5% was considered statistically significant. All statistical analyses were performed with SPSS version 26 (SPSSInc, Chicago, IL, USA).
4. Discussion
The results of the present study showed moderate levels of QoL in the pre-PCI period, and an increase in QoL scores 6 and 12 months post-PCI. The QoL measurement prior to this minimally invasive procedure provides significant insights into the selection of patients and offers a base to clinicians to provide individualized care afterward [
6,
12,
14].
In the pre-PCI period, regarding gender, a lower QoL was observed in women across all subscales, apart from physical functioning, emotional well-being and physical pain. This finding is similar to other relevant studies conducted worldwide. For example, in Australia, among 16,517 patients (22.9% women), the female sex was a predictor of a poor QoL after PCI for acute coronary syndromes (ACSs), including anxiety and depression [
15]. Contrariwise, in Poland no significant differences in the QoL between the sexes were found in a 36-month follow-up of PCI [
16]. In Netherlands, after coronary revascularization (coronary artery bypass graft or PCI), women reported a slow improvement in physical state, irrespective of the comorbidity burden [
17]. In a period of 12 months post-PCI, women in Vietnam showed a better recovery in mobility, despite having had a worse QoL 30 days after discharge [
18], whereas those in the “Antiplatelet Therapy Observational Registry” reported a lower QoL [
19]. Clinical factors may possibly affect QoL, as women have a higher prevalence of diabetes mellitus, systemic hypertension, chronic renal insufficiency, peripheral arterial disease, congestive heart failure, as well as a lower body surface area and higher body mass index [
20]. Furthermore, women may invest their experiences with a different personal meaning. Perceptions affect treatment and expectations or efforts for recovery, as well as participation in rehabilitation programs [
21]. Beyond the shadow of doubt, all the aforementioned parameters influence the QoL.
As far as age is concerned in the pre-PCI phase, participants over 70 years old and those 61–70 years had a worse QoL in the subscale of energy–fatigue and general health, respectively. In general terms, elderly patients have a better QoL compared to: (i) the pre-PCI phase, (ii) patients who follow conservative treatment, (iii) age-matched general population and an equivalent or superior QoL compared to younger patients who underwent PCI. These benefits are observed for at least one year [
22], while the greatest improvement is noticed in physical health compared to young groups [
23]. Possibly, the elderly derive greater benefits from revascularization, as they have more cardiovascular risk factors and a greater burden of ischemic disease. Another aspect that could explain the better health status in the elderly is that they are more accepting of their functional impairment. Noteworthy, the elderly are more likely to experience procedural complications owing to age-related physiological changes, frailty, or comorbidities, and are less likely to be employed or have dependents requiring their support [
23,
24]. Despite the risks of performing PCI in elderly patients, the decision must be considered in relation to benefits for QoL. Peri-procedural mortality rates appear to be higher in the elderly, but if they survive this procedure, they lead an acceptable QoL. Given these benefits, it is important not to abandon elderly patients in the inadequate management of conservative treatment. Delay or exclusion from intervention or research studies solely based on age may reject patients from receiving the best evidenced practice care [
22]. Finally, and most strikingly, age per se should not deter against revascularization, since there are QoL benefits [
23].
Moreover, in the pre-PCI phase, participants with a primary education had worse physical and social functioning, emotional and physical roles, energy–fatigue and general health. A possible explanation is that education supports patients to develop adaptive mechanisms and become able to handle their health needs more effectively. A low level of education seems to affect the QoL through reduced use of preventive health services, less awareness of their medical condition and poor self-care behaviors [
25]. Additionally, the level of education either hinders or promotes the understanding of information provided by health professionals [
26]. Education changes people’s attitude and leads to improvements in the QoL [
27]. Patients with a higher income and education experienced a better QoL 6 months after revascularization [
28].
According to the present results, in the pre-PCI phase, the retired participants had a worse QoL in the domains of physical and social functioning, emotional role, energy–fatigue and general health. Participants who still work possibly keep in contact with other individuals, maintain communication and receive social support, thus enjoying a better QoL [
29]. However, in developing countries, the low socio-economic status (income, occupation, education) is associated with a higher incidence of major adverse cardiac events post-PCI, thus indirectly influencing the QoL. More specifically, patients with a low socio-economic status are less adherent to medication and therapeutic advice after PCI. At the 12-month follow-up, the revascularization repeat and the recurrent myocardial infraction were higher in the low socio-economic group [
30]. Therefore, evaluating the socio-economic status in the pre-PCI period is essential to take the necessary steps post-PCI.
Widowed patients had a worse QoL in energy–fatigue and social functioning in the pre-PCI phase. This finding is partially attributed to diminished support compared to those living in marital bonds. The prevailing view is that family support is associated with health-promoting self-management and adherence to treatment. Moreover, social interaction promotes health because it maintains a rhythm of life [
31,
32,
33]. It is likely that family support provides a sense of security and a peaceful environment to individuals, which enhances their confidence to overcome disease-related difficulties, thus improving QoL. [
10,
11] An increase in social support by significant ones, family, or friends leads to a decrease in state and trait anxiety among cardiac patients [
32]. Apart from the lack of supportive environment, the widowed may experience difficulties in handling practical issues or performing daily activities alone. Therefore, a trusting relationship with health professionals may improve the QoL by presenting treatment options with clarity and actively enhancing participation in the decision-making process [
29,
34].
Moreover, patients who did not smoke had a worse QoL in the emotional role subscale. QoL evidence promotes smokers and health professionals to become more sensitive about the adverse effects of smoking. Notably, smoking increases the risk of myocardial infarction and death in patients with heart disease, especially after PCI. Smoking limits vascular reconstruction and coronary blood flow by creating microvascular endothelial dysfunction, and reduces the ability to exercise. Thus, smoking may diminish the QoL [
27]. Moreover, patients with a family history of coronary artery disease had a worse QoL in the dimension of emotional well-being. Contrariwise, evidence supports that individuals having a positive cardiac family history may better comprehend the important role of self-care, thus improving the QoL [
27].
Patients who never exercised had a worse QoL in physical functioning, physical role, energy–fatigue, emotional well-being and general health. It is widely known that the treatment of coronary artery disease involves interventions (diet, risk factors modification, exercise) beyond pharmacologic therapy and coronary revascularization. Exercise plays a vital role in the QoL improvement. A 12-week exercise cardiac rehabilitation showed greater improvements in maximal oxygen uptake among elderly patients undergoing PCI [
35]. Likewise, an improvement in health status after PCI for chronic total occlusion was associated with participation in regular exercise [
36]. Early home-based exercise in patients with myocardial infraction who underwent PCI may improve cardiac function, reduce postoperative complications, and enhance cardiac antioxidant capacity and exercise ability, thus promoting the QoL [
37]. A cardiac rehabilitation program using home exercise training with wireless monitoring led to the improvement of both exercise capacity and QoL in patients undergoing PCI [
38]. Developing interventions to safely increase exercise in this vulnerable population may improve the QoL.
Last but not least, shaping future and appropriate interventions demands an in depth understanding of patients’ perceptions associated with QoL in the pre-PCI period. Unfortunately, some patients underestimate cardiac disease for various reasons, such as the short time of procedure and hospital stay, prompt improvement of symptoms and early return to prior activities [
39]. In Sweden, among 1073 patients after PCI, 67% perceived that they were cured, 38% declared no need to change their habits, 16% continued to use tobacco and fewer than 50% were regularly physically active. Nutritional counseling was provided to 71%, but only 40% changed food habits. Only 27% reported that they still had cardiovascular disease and needed behavioral change [
40]. If in such cases is added the psychological stress in cardiac illness, then treatment becomes more complicated [
41].
The results of the present study showed an increase in the QoL score 6 and 12 months post-PCI, with a greater improvement in physical functioning, physical role, emotional role and social functioning. Similarly, in the United Kingdom, PCI improved the QoL, especially physical functioning, vitality and general health, at both 3 months and 1 year, but not at three years [
14].
The following results were observed at 6- and 12-month QoL measurements: (i) patients who never exercised or exercised 1–2 times/week had a greater increase in physical functioning score, (ii) patients >70 years old had a lower tendency to increase the score in physical role, emotional well-being, social functioning, physical pain and (iii) patients with a family history of coronary disease tended to increase the score in physical role, emotional well-being, physical pain and general health. Among participants that were 61–70 years old, a great tendency to increase the score of physical role, emotional well-being, social functioning, physical pain and general health was observed.
At the 3-year follow-up after PCI, the significant independent determinants of a lower QoL included the female sex, age >60 years and diabetes mellitus [
16]. According to van den Berge et al., [
42] studies including a 12-month follow-up have shown that age, the male gender, renal impairment, smoking and prior coronary artery bypass grafting were predictors of health status post-PCI. At 10 years post-PCI, the SF-36 scores at baseline, age and previous PCI were significant predictors of subjective health status. Evaluating the QoL at baseline is a useful indicator to predict the long-term subjective health status [
42]. Modification of the SF-36 score is a key challenge for clinicians involved in the care of PCI.
6. Conclusions
The present study showed a moderate QoL pre-PCI and an improvement 6 and 12 months afterward. Over time after PCI, patients aged >70 years had a lower tendency to increase the QoL score, whereas patients with a family history of coronary disease tended to increase the QoL. Moreover, a greater increase in physical functioning score over time was observed in patients who never exercised or exercised 1–2 times/week.
Prior to PCI, a worse QoL was observed: (i) in patients with a primary education, more than one child, who were retired and never exercised in regards to physical functioning; (ii) in female patients, patients with a primary education and those who never exercised in regards to the physical role; (iii) in female patients, those with a primary education, retired ones and those who did not smoke in regards to the emotional role; (iv) in female patients, the widowed, the retired ones, those older than 70 years, as well as those with a primary education, with some other disease, more than one child and those who never exercised in regards to energy–fatigue; (v) in patients with a family history of coronary artery disease and those who never exercised in regards to emotional well-being; (vi) in female patients, widowed ones, those with a primary education and retired ones in regards to social functioning; and (vii) in female patients, over 60 years old, with a primary education, retired ones, with some other disease and those who never exercised in regards to general health.
Further research should explore the determinants of the QoL in larger multicenter studies. Needless to say, the QoL is an undeniable right in any society.