3.1. Caregiver Burden
A study that administered the Caregiver Burden Inventory (CBI) to 86 caregivers of patients with AD showed a direct link between the severity of the disease and caregiver burden. The study also showed that the caregiver role was often taken by the wife or daughter of the patient with AD.
Studies have shown that there are many repercussions on the physical and mental health of caregivers of patients with AD, as well as altered family relationships, job loss followed by financial difficulties, and even an increase in mortality.
Female caregivers often become physically, emotionally, and financially overwhelmed. Their time is permanently restricted, and they can lose a number of opportunities. They generally look for strategies based on emotions, making their burden even more difficult [
14].
It is well-known that a good medical and care service benefits the elderly by improving their self-esteem, quality of life, and mental health, and according to recent studies, these benefits are also reported among the family members [
15].
3.2. Music, a Form of Therapy
Throughout history, with the desire to improve the effects of drug therapy, steps have been taken to develop a complex care plan to increase people’s quality of life. In 1997, Cohen-Mansfield and Werner stated that to improve the daily lives of the elderly in a residential center; they must be involved in activities that are enjoyable but also stimulating [
16]. Different studies have tried to demonstrate the effectiveness of music in various psychiatric pathologies, including dementia. Since art is more conductive to qualitative than quantitative evaluations, studies on this subject are challenging.
In 2010, a randomized clinical study (RCT) was conducted by Cooke et al. on music therapy influences on people with dementia who also experienced behavioral disorders and anxiety. Their results indicated that music therapy or reading therapy interventions had minimal benefit, and only some of the participants showed any improvements [
17].
However, improvements in speech, behavior, and depressive symptoms through music therapy interventions have been demonstrated by Brotons, M. and Koger, S.M. The previously mentioned study demonstrated that speech content and fluency as evaluated by the spontaneous speech subscale of the WAB (Western Aphasia Battery) were superiorly improved following musical therapy than as a result of oral sessions with a specialized therapist [
18].
There is an ongoing randomized parallel-design controlled trial with the aim of assessing the effects of reminiscence therapy on cognitive, emotional, behavioral, and psychological symptoms, daily living activities in patients with dementia in addition to conventional drug treatment., musical therapy, also being investigated [
19].
The efficacy of individualized recreational therapy was shown to be beneficial to dementia-suffering subjects by reducing their disturbing behavior described as passive (lack of motivation or initiative), agitated (wandering, verbal or physical aggression), or mixed [
20]. Minimizing the agitation of elderly patients through either calming music and hand massage or a combination of both has been explored in a nursing home setting, and the results suggest that interventions performed separately offer the same improvement as combining the two types of interventions [
21].
A 2004 randomized control study evaluated the state of mood and cognitive function in women with dementia before and after performing music-based physical exercise interventions and concluded that measurements of both Mini-Mental State Examination (MMSE) and the Amsterdam Dementia Screening Test 6 (ADS 6) were improved as a result of the above-mentioned therapy, these findings are supported by a similar study done in Taiwan by Sung H.C. [
22,
23]. Engaging nursing home residents diagnosed with Alzheimer’s disease in recreational activities such as games and songs, which encouraged hand to eye coordination, range of movement, cognitive, respiratory, and circulation functions, have yielded unsatisfactory results in the long term, whereas the state of effect during and immediately after the activities has only shown modest signs of improvement [
24]. Short-term improvements have also been observed during a case-control study carried out by H. B. Svansdottir and J. Snaedal focused on the dynamics before and after musical therapy intervention of activity disturbances, aggressiveness, and anxiety. Delusional ideation suffered no improvement. The effect had subsided 4 weeks after the therapy was halted [
25].
Throughout history, aspects such as mood swings have been studied, with the predominant presence of depression among the elderly. Specialized studies have associated depression with changes in the level of cortisol in the human body. Corticosteroids are hormones that play an essential role in the human brain and have been associated with noticeable changes in areas such as mood, eating and gregarious instincts, nictemeral rhythm, and cognitive function. The main glucocorticoid, cortisol, can cross the blood-brain barrier due to its lipophilic structure and has the ability to cause changes in the hypothalamic-pituitary-adrenal axis. Multiple studies have shown a connection between elevated cortisol levels and the symptoms associated with Alzheimer’s dementia [
26,
27,
28], particularly affective symptoms. Elevated levels of cortisol in institutionalized older adults were described by Holland et al. [
29]. In 2013, data were published from an RCT by Chu et al. on the cortisol level in the saliva of elderly people included in a music therapy program, and although the data were not concrete in this respect, an improvement in disposition was described, which was not reversed after the study ended [
30].
According to data published in 2018 by Lyu et al., the use of music therapy in approximately 300 patients with Alzheimer’s dementia proved effective compared to alternative techniques, such as reading music lyrics, and the quality of life of their members improved at the same time [
31].
Psychomotor agitation is one of the problems faced by specialists who care for people with dementia of any kind, and these episodes cause genuine discomfort. Thus, several studies [
12,
32,
33] have conducted randomized investigations in multiple elderly centers using a person-centered approach, in which the music therapist applied several series of sessions for up to 18 weeks, depending on the study. The results confirmed that the positive effect of music therapy was significant and associated with improvements in disruptive behavior and a decrease in the number of psychotropic substances used during therapy. However, data are insufficient to support the hypothesis of long-term improvement.
It is recognized that the right cerebral hemisphere controls certain artistic behaviors and abilities. Researchers have observed that the functional musical residue is maintained in people with neurocognitive disorders and aphasia due to injuries in the left hemisphere. Thus, some specialists in the medical field have decided to use music therapy not only for the beneficial effects on mood symptoms and social skills but also as an adjunct in oral rehabilitation and respiratory control [
34,
35]. Thus, once involved in musical activities, patients can develop certain skills and simultaneously engage in respiratory gymnastics.
Throughout history, medical research in the field of cognition has existed to facilitate potential therapeutic interventions, and several blood biomarkers have been discovered that have a recognized involvement in the development of neurocognitive disorders. In particular, the studied neurodegenerative elements include β-amyloid plaques, plasma levels, and leukocyte telomeres. According to some studies, the accelerated aging process in Alzheimer’s dementia is associated with short leukocyte telomeres, although further investigation is needed, and there is no unanimous consensus to support the hypothesis fully. Randomized studies were performed to evaluate these hypotheses, such as the research conducted by Innes et al. on the influence of alternative therapies, such as music therapy and meditation, on blood biomarker levels and improvement in quality of life and behaviors. However, further investigations are needed [
36,
37,
38,
39,
40,
41].
In we inserted the relevant studies for musical therapy and in we showed study characteristics regarding musical therapy [
17,
18,
19,
20,
21,
22,
23,
24,
25,
30,
31,
32,
33,
40,
41].