Predictors and Moderators of Quality of Life in Alzheimer’s Disease Patients

Abstract

Background: Alzheimer’s disease (AD) is a chronic degenerative disease leading to global cognitive and functional decline. Quality of Life (QOL) is an important variable in the effectiveness of intervention programs in dementia.

Objective: This study analyzed the relationships between gender, psychological variables and QOL, the predictors of QOL, and the role of spirituality as a moderator between functionality and QOL.

Method: A cross-sectional study was conducted with 128 patients with mild AD.

Results: Being a male, good social support, and high functionality were significant predictors of better QOL. Spirituality was a moderator in the relationship between functionality and QOL.

Conclusion: These results reinforce the importance of gender, psychological morbidity, social support, and functionality, with special emphasis on the role of spirituality, regarding intervention programs that promote QOL, in patients with mild AD.

Keywords

Alzheimer’s disease quality of life self-care spirituality

INTRODUCTION

Alzheimer’s disease (AD) is considered a chronic, degenerative disease of gradual evolution, which leads to a decline of cognitive and global functioning [1 –3], making the patient dependent on support. According the World Alzheimer Report put out by Alzheimer’s Disease International [4], based on the 2010 Census, about 5.3 million Americans of all ages have AD with about 200,000 under the age of 65 [4]. In Portugal, AD affects about 60% of patients with dementia [5]. As a result, Quality of Life (QOL) has become an important measure to assess in patients with AD [6], as well as the effectiveness of intervention programs in dementia [7, 8]. This article addresses QOL in AD patients, taking into consideration the patient’s perspective.

Previous studies have shown that male patients [9] report a better QOL and a lower impact of the disease on their daily lives as compared to women [10], showing the importance of gender on QOL in AD patients.

The literature revealed that depression in AD patients is responsible for the loss of the capacity to carry out activities of daily living (ADLs), ultimately resulting in decreased QOL and faster cognitive decline [11 –13]. Therefore, psychological morbidity has been associated with increased incidence and progression of AD and higher risk of institutionalization [14 –16]. Not surprisingly, participation of AD patients in social activities has a protective effect on cognitive decline, related to better cognitive functioning [17 –19], higher life satisfaction [20], less depression, and better QOL [21, 22].

In AD patients, family functioning and interpersonal relationships are severely compromised [23], requiring adaptation, reorganization, and coping strategies [24]. In families of AD patients presenting higher levels of anxiety and depression, in comparison to other chronic diseases [25], coping strategies are fundamental. These strategies demand for the integration of difficulties in daily chores and social relationships that affect QOL [26, 27]. Coping strategies allow the AD patient to maintain family and social life within the normal range [28]. The patient’s main goal is to maintain his personal self-image, hope, and life objectives [26]. However, the goal to preserve self-perception and awareness of the disease, as a coping strategy is not exempt of difficulties. In fact, the worsening of cognitive and functional status in AD is associated with the loss of awareness of the disease [29, 30], in particular the loss of cognitive symptoms that lead to limitations [30 –32]. Cognitive impairment may also involve greater difficulties in responding to daily life demands that affect AD patients, who often use emotion-focused rather than problem-focused coping strategies [33]. Still, preserving the awareness of the disease will allow patients to, mobilize coping resources to deal with difficulties in ADLs [30].

Mindfulness is focused on the attention to the self, concerning internal or external experiences that are happening [34], without making any judgment on the relevance of the causes or consequences of the situation [5], emphasizing the present moment. At the cognitive level, mindfulness increases attention [35], resulting in an improvement of the working autobiographical memory [35, 36], and significant improvements on selective and focused attention as well as executive skills [37].

Spirituality/religion are dimensions that play an important role in the adjustment to a chronic disease [38] and the patient’s wellbeing [39, 40], and may function as a coping strategy [41, 42]. Patients with mild AD may still have their spirituality preserved to face the challenges of their cognitive loss [41, 43], finding a significant inner meaning to deal with their difficulties. Spirituality has been associated with better perceived QOL [44], allowing the patient to feel more confident and maintain self-identity [45]. In fact, spirituality was a moderator in the relationship between stress and QOL, in non-clinical populations (including AD caregivers) [46 –48]. In patients with chronic disease, spirituality was found to be a moderator between several psychological variables such as stress, anxiety, depression, meaning of life, severity of symptoms, and QOL (e.g., dementia, cancer, spinal cord injury, and multiple sclerosis) [46, 49]. Since functional decline in AD is progressive, it is important to study spirituality as a moderator between functionality and QOL in the early stages of the disease [31]. However, the literature seldom focuses on the role of psychological variables taking the patient’s perception into consideration. Most studies have focused on the caregiver’s perception of AD patients [6, 31]. Moreover, since the awareness of the disease is preserved in the early stage of the disease, it is crucial to understand how patients early on adjust to the functional and cognitive impairments that result from AD [30, 31].

In order to fill this gap, the main goal of this study was to analyze, according to the patient’s perception instead of the caregiver’s perception, the associations between gender, psychological morbidity, social support, functionality, coping, spirituality, awareness of the disease, mindfulness with QOL, the predictors of QOL, and the moderator role of spirituality. We hypothesize that psychological morbidity and being a female will negatively contribute to QOL and that social support, functionality, problem focused coping, spirituality, awareness of the disease, and mindfulness will contribute to improve QOL. Finally, spirituality will moderate the relationship between functionality and QOL.

MATERIAL AND METHOD

Participants

The study included a cross sectional design and a convenience sample. In this study, 128 patients with mild AD were recruited from four hospital outpatient clinics, in the northern region of Portugal. Patients’ criteria for probable AD were assigned by the patient’s neurologist, according to the Diagnostic and Statistical Manual of Mental Disorders-V (DSM-V) [1], and the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer’s Disease and Related Disorders Association (NINCDS/ADRDA) criteria [50]. Patients were diagnosed as having mild AD, if they scored 1 on the Clinical Dementia Rating scale [51]. Exclusion criteria included severe psychiatric disorders or cerebral vascular diseases. Patients were asked to participate, on a voluntary, basis by a neurologist, after being informed about the study’s objectives and signing an informed consent form. Regarding the Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia (ASPIDD) [52], caregivers also participated and were asked to confirm the patient’s answers. The study protocol was approved by the local hospital ethics committees, and carried out in accordance with the Declaration of Helsinki.

Measures

Quality of life

The QOL-Alzheimer’s Disease (QOL-AD) [53, 54] is an instrument that assesses the QOL of patients with dementia/AD, reported by the patient and caregiver and consists of 13 items using a Likert scale ranging from 1 to 4, corresponding to one of following dimensions: physical health, energy, humor, living conditions, memory, family, marriage, home ownership, ability to do domestic tasks, engaging in activities that provide pleasure, money, and general life. The overall result range from 13 to 52, with higher scores indicating better QOL. In this study, the alpha was 0.88.

Psychological morbidity

The Hospital Anxiety and Depression Scale (HADS) [55, 56] evaluates anxiety and depression in patients with physical diseases, and comprises 14 items(7 items in the depression scale and 7 items in the anxiety scale) using a Likert scale ranging from 0–3. The overall score, in each subscale, ranges from 0 to 21. A higher score indicates more anxiety and depression respectively or emotional distress, globally. In this sample, the alpha in the anxiety subscale was 0.72 and in the depression subscale was 0.78.

Social support

Satisfaction with Social Support Scale (SSSS) developed by Pais Ribeiro [57] assesses satisfaction with social support, consisting of 15 items which result in four dimensions: Satisfaction with friends / acquaintances (SA); Intimacy (IN); Satisfaction with family (SF); and social activities (AS). The value for the total scale ranges between 15 and 75. A higher score indicates greater perception of satisfaction with social support. The alpha, in this sample, was 0.88.

Functionality

The Index of Barthel [58, 59] assesses the degree of functionality, and focuses on physical disability in ten domains. According to the Portuguese adapted version the cut off score is 60, and a score above 60 indicates greater functionality [59]. The internal consistency in this sample was 0.81.

Coping

The Ways of Coping (WOC) [60, 61] assesses coping skills and consists of 48 items representing eight coping strategies grouped into two subscales of problem focused coping and emotion focused coping. In this study, only the two dimensions were used and the patients were asked to answer the strategies they used to cope with memory problems. A higher score indicates greater use of the respective coping style. In this sample, alphas were 0.82 and 0.77, for problem focused coping and emotion focused coping, respectively.

Spirituality

The Spiritual and Religious Attitudes in Dealing with Illness (SpREUK) [62, 63] is an instrument that assesses how spirituality helps in dealing with a chronic disease. The Portuguese version adapted to AD patients [64], revealed two dimensions: Search of Support and Trust/Reflection [64]. A higher score indicates greater spirituality. The scale showed an alpha value of 0.95.

Awareness of disease

The Assessment Scale of Psychosocial Impact of the Diagnosis of Dementia (ASPIDD) [52] assesses awareness of disease in dementia/Alzheimer’s disease. The original version, consisting of 26 items has four dimensions: awareness of cognitive functions and health status, awareness of the ADLs, emotional awareness and awareness of social status and relationships. A higher score indicates higher awareness. The Portuguese version [65] revealed only one factor with 21 items with an acceptable alphaof 0.70.

Mindfulness

The Cognitive and Affective Mindfulness Scale-Revised (CAMS-R) [66, 67] assesses the regulation of attention, orientation to the experience of the present moment without judgments, and conditioned response patterns. A high score indicates greater use of strategy and quality of mindfulness. The Portuguese version adapted to AD patients [68], revealed one factor that includes 8 items, with an alpha of 0.83.

Data analysis

To assess the relationships between duration of disease, psychological morbidity, social support, functionality, coping, spirituality, awareness of disease, mindfulness, and QOL, a Pearson correlation and a Point-biserial correlation regarding the relationship with gender were performed, respectively. A hierarchical multiple regression was conducted to assess the predictors of QOL in AD patients, including the variables that correlated with QOL. To avoid multicolinearity, the total score of psychological morbidity was used in the regression analysis. In the first step, gender was introduced, and in the second step, all the psychological variables: psychological morbidity, social support, functionality, coping, spirituality, awareness of disease, and mindfulness were added. Finally, a moderation analysis was performed to determine if spirituality was a moderator in the relationship between functionality and QOL using a macro command of SPSS. Statistical analyses were conducted with the software SPSS v.22.0, with a 95% confidence interval.

RESULTS

Sample characteristics

The sample included 128 patients with mild AD, with a mean age of 76 years (SD = 6.92). From the total sample, 65.6% were female, 63.3% were married, lived in an urban region, and the average education level was very low i.e. 3.2 school years. All patients were taking anti-cholinesterase inhibitors. Table 1 presents the characteristics of the sample.

Relationships between gender, duration of disease, psychological morbidity, social support, functionality, coping, spirituality, awareness of disease, mindfulness, and QOL

The results showed a relationship between gender (male) and QOL (r = –0.308, p < 0.01) but duration of disease did not correlate with QOL. A positive correlation between social support (r = 0.422, p < 0.01), functionality (r = 0.396, p < 0.01), awareness of disease (r = 0.282, p < 0.01), mindfulness (r = 0.378, p < 0.01), and QOL was found. Psychological morbidity (r = –0.428, p < 0.01) and spirituality (r = –0.248, p < 0.01) were negatively correlated with QOL. Problem and emotion-focused coping presented no correlation with QOL (Table 2).

Predictors of QOL

The results showed that being a male was a significant predictor of QOL and explained 9.5% of the variance (F (1,127) = 13.161; p < 0.001, Table 3). When the psychological variables were added to the model, being a male, high social support, and high functionality were significant predictors of QOL, explaining 44.4% of the variance (F (7,127) = 13.695; p < 0.001, Table 3).

Spirituality as a moderator between functionality and QOL

The results showed that spirituality was a moderator. The interaction was significant, β= –0.010, 95%, CI [–0.017,–0.004], t = –3.18, p < 0.05 indicating that the positive relationship between functionality and QOL was moderated by spirituality when the latter was lower or higher. However, when spirituality was lower the relationship between functionality and QOL was stronger (β= 0.458, 95%, CI [0.345, 0.572], t = 7.99, p < 0.001) than when spirituality was higher (β= 0.154, 95%, CI [0.037,0.271], t = 2.60, p < 0.05).

DISCUSSION

The goal of this study was to analyze the associations between gender, duration of disease, psychological variables, and QOL, the predictors of QOL, and the moderator role of spirituality in patients with mild AD according to the patient’s own perception. Some findings are in accordance with previous studies that have analyzed the relationship between these variables but not in the patients’ perspective. In this study, low psychological morbidity, high social support, and high functionality contributed to a better QOL, as portrayed in previous literature [20]. In fact, Van der Mussele and colleagues [69] found that AD patients with depression showed behavioral changes, sleep disturbances, irritability, and anxiety, confirming that psychological morbidity or emotional distress, predicted poor QOL [70 –72]. Also, psychological morbidity has been associated with a decline in ADLs, social relationships, and cognitive functioning emphasizing its negative impact on QOL [13, 73]. However, high functionality and an active lifestyle in AD patients are able to maintain cognitive stimulation [74, 75], that is necessary for good QOL. Perceived social support and participation in social activities are related to better cognitive functioning and higher life satisfaction [20], contributing to higher QOL. Awareness of the disease and mindfulness were correlated with better QOL. These results make sense since awareness of the disease reflects an acknowledgment of cognitive and functional limitations [29], and mindfulness is related to less negative automatic thoughts [76] and an improvement in cognitive status [35, 37] that may contribute to a better QOL. In fact, in mild AD, the functional limitations and cognitive impairment are reduced and, in this early stage, the awareness of the disease may not be perceived as impairing QOL. Also, having a great capacity for mindfulness may help the patient to stay focused on the present, reducing the anxiety concerning the future outcome of the disease, which may also result in a better perception of QOL.

Interestingly and contrary to our hypothesis, spirituality was negatively correlated with QOL. Since spirituality is preserved in AD patients, it may play a major role in the way patients find a meaning and understand the disease, as well on how to cope with it, particularly regarding their deficits [42]. The fact that spirituality is connected with a concern with a Higher Power or God may increase the patients’ reflection of the impact of AD on one’s life [49, 64], particularly regarding what is ahead such as the progressive loss of skills and, ultimately death, both beyond their personal control which may contribute to a lower perception of QOL and the need to believe in a spiritual being’s help. Future studies should pursue this hypothesis since this is the first study to explore the role of spirituality in QOL, according to the patient’s perception.

Contrary to our hypothesis, coping (problem or emotion focused) did not correlate with QOL but correlated positively with spirituality. This finding may suggest, that in the mild stage, the type of coping strategies used by patients, with AD, as well as a short duration of the disease which did not correlate with QOL may not impact or be so relevant to QOL but may be important regarding one’s spirituality suggesting the importance of this variable as an important coping strategy.

The results showed that only low psychological morbidity, high functionality, and social support, were significant predictors of QOL. These results were expectable taking into consideration the findings from other studies with chronically ill patients, emphasizing once again the need to include these variables in interventions to promote QOL, in mild AD patients. Also, being a male correlated with QOL and was also a predictor, confirming previous findings [9]. Therefore, intervention needs to be gender specific, in this population. With the exception of gender, few studies have identified sociodemographic characteristics that interfere with QOL [10 , 78]. Male patients with AD [9], in contrast to female patients [79], report better QOL and a lower impact of the disease on their daily lives. In fact, culturally, most domestic tasks are a woman’s responsibility, such as preparing meals, taking care of the home and offspring, especially in rural areas, which are the most represented in this sample. As a result of having AD, daily chores for women, may become increasingly difficult. Therefore, it comes as no surprise that men report better QOL.

Spirituality was a moderator between functionality and QOL, but when spirituality was lower, the positive relationship between functionality and QOL was stronger. The correlation matrix also showed that spirituality was negatively correlated with QOL. This finding is interesting and may be related to the fact that in mild AD patients, functionality is not greatly compromised and is focused mainly on memory complaints or forgetfulness. As a result, in the early stages of AD, when patients perceive themselves as functional, although spirituality may be used as a coping strategy [31 , 64], as we hypothesized earlier, and taking into consideration its moderation effect, patients who resort less to spirituality may be those who perceive themselves as having good QOL. In future studies, spirituality in AD patients should be further analyzed, as the disease progresses, as well as with patients with mild cognitive impairment, to better understand its relationship with QOL. Also, the relationship between problem/emotional-focused coping as a mediator between awareness of disease and QOL should also be analyzed. As far as we know, this is the first study that focused on the moderator role of spirituality in mild AD patients, according to their perspective and more studies are clearly needed in this area.

Limitations

The major limitation of this study is its cross-sectional nature. A prospective study would further clarify the correlation of the psychological variables, especially between spirituality and QOL, as AD progresses. Also, the cohorts of patients in this study showed a low education level, were from a rural area, and were almost all married. Nonetheless, according to the 2011 Portuguese Census, in the age group above 65 years of age, the education level is quite low [80] and elderly patients live mostly in a rural environment [81] and, in this sense, this sample may be considered representative.

Conclusion

The results reinforce the importance of gender, psychological morbidity, social support, and functionality on QOL in patients with mild AD, and highlight the role of spirituality in QOL. Therefore, it is important to develop intervention programs to promote social support, the preservation of functionality and the decrease of psychological morbidity, particularly for women, in order to promote AD patients’ QOL. Women may need more social support, particularly instrumental support and coping strategies to handle the ADLs. Also, the community should provide resources for AD patients to engage in occupational activities that promote social interaction and active cognitive skills.

Footnotes

ACKNOWLEDGMENTS

The authors gratefully acknowledge the contributions of all Alzheimer’s disease patients who agreed to participate in this study.

Authors’ disclosures available online ().

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