This cross-sectional study analyzed the associated and moderating variables regarding QOL, in informal caregivers of CC patients undergoing treatment at the reference hospital for cancer treatment in the State of Amazonas, the Oncology Control Center Foundation of Amazonas (FCECON), in the Manaus capital. The sample was non-probabilistic and calculated based on the estimated number of new cases of cervical cancer treated at FCECON in 2016, taking into consideration a confidence level of 95%, an anticipated effect size of 0.15 and a desired statistical power of .80, with nine variables, and the minimum required sample was 113.

The participants were informal caregivers, 18 years old or over, of patients diagnosed with CC undergoing treatment (chemotherapy/radiotherapy) at FCECON. There were two indigenous patients and, consequently, their caregivers were excluded from the sample due to cultural and linguistic peculiarities.

Sociodemographic questionnaire, assessing age, gender, race, location, marital status, education, occupation, income, family relation towards the patient, cancer stage (patient), and hours dedicated to care.

Burden Interview Scale (BIS; Zarit & Zarit, 1987; Brazilian version by Scazufca, 2002): This instrument assesses the burden in informal caregivers of patients with chronic illnesses with 22 items that refer to concern areas for caregivers, namely health, social and personal life, financial situation, emotional well-being, and interpersonal relations. Questions 1 to 21 are scored as 0 (never), 1 (rarely), 2 (sometimes), 3 (frequently), 4 (always); and item 22 as 0 (not a little), 1 (a little), 2(moderately) 3(very), and 4 (extremely). This last question evaluates the intensity of burden in the caregiver. The total score ranges from 0 to 88 and higher scores indicate greater the caregiver burden. Cronbach’s alpha in the Brazilian version was .87. In this study, Cronbach’s alpha was .84.

SF-36 - Short Form Health Survey (SF36; Ware & Sherbourne, 1992; Brazilian version by Ciconelli et al., 1999). The SF36 assesses physical and mental QOL. It is made up of 36 items in 8 scales or domains, namely functional ability, physical aspects, pain, general health status, vitality, social aspects, emotional aspects, and mental health. Scores are awarded to the 8 domains ranging from 0 to 100, where 0 = worst and 100 = best, for each domain. Thus, the higher the score the better the quality of life. Cronbach’s alpha in the Brazilian version for all items was over .90. The Physical component (general health, functional health, ability, body pain, physical function) showed a Cronbach’s alpha of .68 and the Mental component (vitality, emotional aspects, social conditions), a Cronbach’s alpha of .76.

Career’s Assessment of Managing Index (CAMI; Nolan et al., 1995; Portuguese version by Brito, 2000): This instrument assesses coping strategies used by the caregivers and includes 38 items grouped into three subscales: 1, “dealing with situations/problem solving”, 2, “alternative perceptions of the situation”, and 3, “dealing with stress symptoms”. The 38 items are scored from 0 to 3: 0 (no use), 1 (use/no result), 2 (use/gives some result), and 3, (use/gives good result). High results indicate greater use of more effective coping strategies. In the original version, Cronbach’s alpha was .84, .80, and .37, respectively, for the three subscales, and .90 for the total scale. In the Portuguese version, Cronbach’s alpha for the total CAMI was .80 and for the subscales .75, .62, and .60. In this study, an exploratory factor analysis was performed for the Brazilian population. The Brazilian version has one less item (27) than the original version and has 2 domains: one with 25 items and another with 14 items, totalising 37 items. Both domains were renamed for semantic adequacy to the content. Cronbach’s alpha was .78 for Alternative’s perceptions/Dealing with situations in the domain with 25 items and .67 for the Problem Resolution domain. The alpha for the global scale was .82.

Hospital Anxiety and Depression Scale (HADS; Zigmond & Snaith, 1983; Brazilian version by Botega et al., 1995). This instrument has 14 items grouped into two subscales, anxiety and depression, with seven items each to evaluate depression and anxiety. Each item can be scored from 0 to 3, adding up to a maximum score of 21 points for each scale (anxiety and depression). The cutoff points for HADS anxiety in the Brazilian version are 0 to 8 - no anxiety, and ≥ 9 anxiety and for HADS depression, the cutoff points are 0 to 8 no depression, and ≥ 9 for depression. In the Brazilian version, Cronbach’s alpha for depression subscale was .77 and for anxiety subscale was .68. In this study, the Cronbach’s alpha for the anxiety subscale was .70, for depression subscale .55, and the global scale was .73. In this study, only the global scale and the anxiety sub-scale were used.

Spiritual and Religion Attitudes in Dealing with Illness (SpREUK; Bussing, 2010; Brazilian version by Pereira et al., 2019). This instrument has 15 items divided into three subscales: 1-Seeking support/access, 2-Confidence in a superior orientation/source, 3-Reflection and positive interpretation of the disease. SpREUK items are scored in five points scale from disagreement to agreement, 0 (not applicable at all), 1 (not really applicable), 2 (I do not know - neither yes nor no), 3 (little applicable), and 4 (applies a lot). Scores can be referred to a 100% level (transformed scale score). Scores > 50% indicate greater agreement (positive attitude), while scores < 50% indicate disagreement (negative attitude). Higher results indicate greater use of spirituality. The original version of this instrument showed Cronbach’s alphas ranging from .86 to .91. In the Portuguese version, Cronbach alphas vary between .81 and .86. This instrument was used for the first time with the Brazilian population and the Brazilian validation has one less item (4). The adapted Brazilian version differs from the original instrument and includes two subscales and 14 items. The two subscales have been renamed for semantic adaptation. The “spiritual support” subscale has 9 items and the “reflection and positive interpretation of the disease” subscale has 5 items (26). Confirmatory factor analysis showed the following results: χ² = 103.82, df = 76, CFI = .976, TLI = .971, RMSEA = .056, RMSEA 90% CI = .081. In this instrument, Cronbach’s alpha for the spiritual support subscale was .72 and for the reflection and positive interpretation of the disease subscale it was .72. Cronbach’s alpha for the global instrument was .81.

Data collection took place from August 2017 to October 2018. Caregivers were interviewed separately in an office while they waited for patients’ consultations at the Chemotherapy and Radiotherapy Outpatient Clinic at FCECON. Participation in the study was voluntary and all participants signed an informed consent form before participating in the study. The study was approved by the ethical committee of the hospital. The consent form was read to the illiterate and fingerprints were collected upon agreement. Caregivers who met the inclusion criteria were randomly selected by patients’ medical records on alternate days of the week during radiotherapy/chemotherapy sessions. The study was approved by the FCECON Teaching and Research Committee and by the National Research Ethics Committee, Brazil (CAAE no.68816417.0.0000.5020).

Data analysis was performed using IBM SPSS® (Statistical Package for the Social Sciences), version 26.0. Descriptive statistics were used to describe the sociodemographic characteristics of the sample (mean, standard deviation, frequencies, and percentages). The Pearson’s correlation test was used to assess the relationship between sociodemographic and psychological variables. Linear multiple regression was used to evaluate the contribution of the variables that best explained QOL: the dependent variable was QOL and the predictive variables were burden, coping, spirituality, anxiety, and the sociodemographic variables correlated with physical and mental QoL. Demographic variables were included in step 1, followed by psychological variables in step 2. Multicollinearity was tested in the two models, and VIF values were well below 10 and the tolerance statistics all well above 0.2 (Field, 2009). The variable gender was categorized as 1 for female and 0 for male.

The moderating role of spirituality in the relationship between anxiety and mental/physical QOL was assessed using Macro Process command for SPSS version 26 and the Johnson-Neyman technique (JN), since all the assumptions for moderation were met.

The sample consists of 119 caregivers of patient undergoing chemotherapy/radiotherapy for cervical cancer at FCECON. The average age of informal caregivers was 37.1 (SD ± 12.2); 70% of the caregivers were female, 78.2% declared to be grayish-brown, and 63% lived in the capital of the state of Amazonas, Manaus. Regarding marital status, 55.6% of caregivers were married. Most caregivers attended school for 9 years or more (58.8%) and 63.9% were unemployed. The family income of 69% of the caregivers was 2 Brazilian minimum wages ($368 USD monthly income). In this study, 68.9% of the caregivers were family members and 59.7% spent between 18 to 24 hours/day taking care of the patient (Table 1).

Table 1

The results showed an association between being a male caregiver and burden (negative association indicates male gender). There was also an association between being a female (positive association indicates female gender) and the use of spirituality (reflection and positive interpretation of the disease). There was an association between education (number of years) and coping strategies, in which caregivers with higher education reported better coping strategies. Caregivers’ family income was negatively associated with coping strategies, i.e., caregivers with higher family income showed worse coping strategies. Table 2 presents the sociodemographic and psychological variables and their association with mental and physical QOL.

Table 2

*p < .01, **p < .001.

Number of caregiving hours showed a positive correlation with burden, indicating that the more time dedicated to care, the greater the burden. Burden had a positive association with anxiety and was negatively associated with the caregivers’ mental QOL, and so the higher the burden the greater the symptons of anxiety and worse the mental QOL (Table 2).

The use of spirituality (reflection and positive interpretation of the disease) was associated with better coping strategies. Poor caregivers’ mental QOL showed a positive relationship with more symptoms of anxiety. Finally, better physical QOL was associated with better mental QOL and more effective coping strategies (Table 2).

In the model that tested psychological variables that contributed to caregivers’ mental QOL, burden (r = -.316, p < .01) and anxiety (r = -.268, p < .01) were included as they were significantly correlated with mental QOL (Table 2). The results showed that the regression model was statistically significant and explained 12% of the variance, R² = .12, F(2, 116) = 8.188, p < .01, but only burden (β = -.249, t = - 2.62, p < .00) was associated with mental QOL (Table 3). Since only coping contributed to physical QOL, regression analysis could not be performed.

Table 3

*p < .01, **p < .001.

Regarding the moderating role of spirituality (reflection and positive interpretation of the disease) in the relationship between anxiety and caregiver’s mental QOL, the model was significant, F(3, 115) = 5.93, p < .00, β = -.23, 95% CI [ -.44, -. 03], t = .02, p < .05, explaining 11% of the variance. Thus, low spirituality (reflection and positive interpretation of the disease) had a negative relationship with anxiety and mental QOL, β = - 3.84, 95% CI [-.44, -. 03], t = 4.02, p < .01. The Johnson-Neyman technique (JN) revealed that anxiety was negatively correlated with mental QOL when the standardized value of spirituality (reflection and positive interpretation of the disease) was 40.98 below the mean (β = -1.98, p = .05) and this happened in 33% of the sample of caregivers (Figure 1)

Figure 1

Finally, the moderating role of spirituality (spiritual support) in the relationship between anxiety and mental QOL (β = .41, p = .34) was not significant.

This study used a cross-sectional design that does not allow causal inferences, a modest sample size and used only self-report questionnaires. Therefore, future studies should replicate the findings in bigger samples and use longitudinal designs to study the variables that contribute to caregivers’ QOL, over time, as patients’ disease progresses.

The results show that coping strategies were associated with better physical and mental QOL. Burden was the psychological variable with the greatest impact on mental QOL showing the importance of interprofessional teams in to include also behavioral health professionals that help caregivers decrease their burden and psychological morbidity (anxiety) in order to improve QOL.

The findings of this study underline the need to develop intervention programs for informal caregivers of Amazonian women with cervical cancer, focusing on psychological morbidity in order to prevent and reduce burden as well as emphasizing the use of spirituality as a coping strategy. According to the results, there is a need for interprofessional teams in oncology settings to assess and intervene the patient-caregiver dyad, in order to decrease caregiver burden, and indirectly promote a patient’s adjustment to CC.