Study design
This cross-sectional study was conducted on oncology patients in a Peruvian public institution specializing in cancer.
Setting
The application of the study protocols was performed for 2 months (July and August 2018) by psychologists and psycho-pedagogues of the Mental Health Unit of the “National Institute of Neoplastic Diseases” (INEN, acronym in Spanish) who were previously trained in the administration of psychometric tests. The tests were administered to each of the patients with confirmed cancer separately, in areas of mental health, hospitalization, and oncology outpatient clinics: breast and mixed tumors, gynecology, medical oncology, abdominal, head and neck, urology, thorax, neuro-oncology, and orthopedics.
Participants
The study sample included 500 participants using the following inclusion criteria: being cancer patients of the National Institute of Neoplastic Diseases, being older than 18 years of age, and having the ability to read and write. Also, patients presenting physical discomfort during the application of the tests and those with cognitive disabilities that limit comprehension and ability to complete the instruments administered for this study were excluded from the study. Due to the nature of the sample, the sampling was purposive and non-probabilistic.
The sample size was calculated based on Poisson regression, assuming a small effect size (PR = 1.2), a probability error of 0.05, and a power of 95%. A total of 453 participants were estimated, to which an additional 10% was added based on the probability of rejection, noncompliance with inclusion criteria, and missing data. Thus, a total of 500 participants were included for the study.
Variables
Anxious symptoms
Anxiety symptoms were assessed using Beck Anxiety Inventory (BAI). Anxiety in BAI can be defined based on the criteria for anxiety described in the DSM-III, which are different from depressive symptoms [40]. Likewise, to differentiate anxious symptoms from depressive symptoms we can define anxiety as fear, tension, and apprehension usually associated with anticipatory ideas of what may happen in the future and the activation of the autonomic nervous system [41]. The BAI is a 21-item self-applied scale created by Beck et al. in 1988, which measures the severity of anxiety symptoms in adults and adolescents in psychiatric populations [42]. The BAI is evaluated using a scale from 0 to 3 (0 = Not at all, 1 = Slightly, 2 = Moderately, and 3 = Severely), so the minimum score is 0 and the maximum is 63 points. The questions refer to the last week and the current moment; administration can take approximately 15 minutes. It shows a high internal consistency (α = 0.93) and evidence of internal structure [43]. Anxiety symptoms according to their scores are classified as normal (0–9), low anxiety (10–18), moderate anxiety (19–29), and severe anxiety (30–63) [44].
Perceived stress
The self-reported perceived stress scale with 10 items (PSS-10) was used to assess perceived psychological stress. Perceived stress was defined as the level of stress that the subject experiences as a function of objective stressful events, coping processes, and personality factors, among others [45]. PSS-10 is composed using a scale from 0 to 4 (0 = Never, 1 = Almost never, 2 = Occasionally, 3 = Often, and 4 = Very often). Psychometric studies of this test have been conducted in different countries, obtaining adequate scores for two-factor models [46–48]. Moderate and severe stress symptoms are defined using a cutoff value of 14 and higher [49].
Depressive symptoms
The Beck Depression Inventory-Second Edition (BDI-II) was used to assess depressive symptoms and is defined in the specific subtype of depression of the Diagnostic and Statistical Manual of Mental Disorders-Fourth Edition (DSM-IV) [50]. The BDI-II is an inventory created by Beck that assesses the severity of depressive symptoms in psychiatric patients and in adolescents and adults (13–80 years) during the last 2 weeks [50]. The BDI-II consists of 21 items and 4 response alternatives ordered from the least to the greatest severity. The response alternatives are scored from 0 to 3 (0 = Not at all, 1 = Slightly, 2 = Moderately, and 3 = Severely), with a maximum and minimum scores of 63 and 0, respectively. This inventory presents high internal consistency (α = 0.94) and evidence of internal structure [51]. Depressive symptoms are classified based on their scores as mild depression (14–19), moderate depression (20–28), and severe depression (29–63) [52].
Emotional distress
Emotional distress was assessed using the Hospital Anxiety and Depression Scale (HADS). The National Comprehensive Cancer Network (NCCN) defines distress as an unpleasant multidetermined emotional experience of a psychological, social, and spiritual nature that can interfere with the ability to effectively cope with cancer, its physical symptoms, and its treatment [53]. This emotional response ranges from common normal feelings of vulnerability, sadness, and fear to problems that become disabling, such as depression, anxiety, panic, social isolation, and spiritual crisis [53]. The HADS was created by Zigmond and Snaith in 1983 [54] and was translated from English into Spanish by Tejero et al. in 1986 [55]. This tool consists of 14 items and two subscales (each with 7 items) that assess symptoms of anxiety and depression at a cognitive and discomfort emotional level in patients with somatic illnesses during the last week. The HADS has a Likert-type response option from 0 to 3, so the scores on each subscale range from 0 to 21. For both scales, if they exceed 8 points, it is considered a “case” and scores higher than 11 points are a “probable case” [54]. However, a meta-analysis study suggests that cancer patients consider a cutoff point scores greater than 15 for the total HADS (sensitivity, 0.87; specificity, 0.88) [56].
Quality of life
The quality of life was assessed using the 12-item short form questionnaire (SF-12). The SF-12 assesses eight domains of quality of life: the first four related to physical health (general health, physical functioning, physical role, and body pain) and the other four related to mental health (vitality, social functioning, emotional role, and mental health) [57]. The response options to the SF-12 items are dichotomous (yes or no) and Likert-type. Response options are scored, weighed, and summed to produce physical and mental component scores ranging from 0 to 100, with higher scores indicating better quality of life in that domain. The SF-12 scoring was performed using the STATA package developed by Bruun [58].
Covariates
Other sociodemographic variables assessed in the study included the following: sex (women/men), age grouped into four groups of approximately 15 years each (17–29, 30–44, 45–59, and 60 years and older); type of care (outpatient clinic, outpatient, and hospitalization), civil status (with a current partner, separated or widower, and single), educational years (primary education [at least 6 years old], secondary education [7–11 years], and superior education [12 to more years]), and employment status (employed and unemployed). Moreover, the variable types of cancer (focused/unfocused) are considered, prioritizing cancers with the highest mortality worldwide with sufficient frequency (lung cancer [bronchi, lungs, and trachea], colorectal cancer, gastric cancer, breast cancer, cervical cancer, and other focal types of cancer) [36]. Additionally, the clinical stage variable (early stages [0, I], advanced stages [II, III, IV], and there is no record) and comorbidity of mental health problems (number of mental health problems that participants have) were included.
Statistical analysis
Characteristics of the participants
In the descriptive analysis, the frequencies and percentages of all sociodemographic variables and the prevalence of depressive, anxiety, and stress symptoms have been reported. Furthermore, an analysis of the prevalence of moderate to severe symptoms of mental health problems (anxiety, depression, stress, and emotional distress) and the quality of life in relation to clinical stage and the types of cancer with the highest overall mortality was performed.
Mental health and quality of life outcomes
Mental health outcomes were defined as variables of anxiety, stress, depression, and emotional distress. These results were dichotomized based on the scores: mild perceived stress (0–13) and moderate to severe perceived stress (14–40), normal to mild depressive symptoms (0–18) and moderate to severe depressive symptoms (19 and above), normal to mild anxiety symptoms (0–18) and moderate to severe symptoms (19 and above), and no emotional distress (0–10) and probable cases of emotional distress (11 or more). On the other hand, quality of life outcomes includes two dimensions: the mental quality of life and physical quality of life. The scores obtained were divided into tertiles that were then dichotomized into low-medium and high (high quality of life was used as the baseline category to facilitate interpretation). Moderate to severe symptoms and low-medium quality of life were viewed as clinically significant for cancer patients and those in need of mental health support (outcomes). A sub-analysis of the comorbidity of mental health problems for the mental quality of life and physical quality of life was performed.
Additionally, generalized linear models with the Poisson family were used to calculate the raw (rPR) and adjusted (aPR) prevalence ratios and their 95% confidence intervals (95% CI) between each covariate and dichotomous health outcomes: the mind and the quality of life. To determine the covariates that would enter the adjusted model, it was taken as a criterion that in the crude model they had a p-value of less than 0.05 to be added to the multivariable model.
Topics of ethics
The study protocol was approved by the INEN Research Ethics Committee and the Research Review Committee (N°239-2018-CIE/INEN). Study participants were invited to participate in the research according to conventional ethical requirements. Subsequently, a signed written informed consent has been obtained from all of the study participants, and a questionnaire has been provided, which consisted of sociodemographic questions and psychometric tests.