Authors: Jenny CC Chung, Claudia KY Lai
Published in The Cochrane Collaboration, 2009.
ARTICLE COMMENTED BY: NICOLÁS LEBRÓN BARRERA. SPORTS SCIENCE AND PHYSICAL ACTIVITY STUDENT (2018-2019). UNIVERSIDAD MIGUEL HERNÁNDEZ DE ELCHE
The word “snoezelen” comes from two Dutch verbs: “sniffen” and “doezelen”. It is a technique generally used in individuals with cognitive problems. Its main objective is to achieve an adequate sensory stimulation. Such stimulation would be difficult on its own, due to the inability of subjects to explore their environments and get sensory stimuli. There is evidence that such sensory deprivation can lead to negative expressions and behaviors (Cariaga 1991; Cohen-Mans 1993; Hallberg 1993). In this sense, indirect treatment in a non-stressful environment with positive stimuli facilitates this sensory experience (Baker 2001; Hope 1998; Hutchinson 1994). Therefore, the term “snoezelen” can be considered as a stimulation of the primary senses (Pinkney 1997). Some authors describe it as a multisensory therapy for people with dementia (Burns 2000). To achieve this, the therapy must aim for positive behaviors and eliminate maladaptive behaviors (Baker 2001, Slevin 1999).
Individuals with dementia have gradual cognitive impairment. Therefore, it is not appropriate to work with large cognitive or communicative demands with this population, as they are less competent and with a lower stress threshold (Hall 1987; Lawton 1986). Two different situations may occur depending on the degree of sensory stimulation. First, excessive stimulation may cause maladaptive behaviors and effects. The second is insufficient stimulation. This may further decrease cognition and function. From these two hypotheses the sensory model of Kovach (2000) is born. In the model, stimuli are carried out achieving equilibrium. “Snoezelen” promotes relaxation and positive behavioral changes (Deakin 1995; Hutchinson 1994), through the application of non-sequential stimuli without a defined pattern, presenting easy cognitive demands. In addition, “snoezelen” positively affects sensory-motor capacity in individuals with dementia (Baker 2001; Beatty 1998; Buettner 1999, Hope 1998). Other authors found that patients with moderate and severe dementia enjoyed and remained calm during the “snoezelen” session (Moffat 1993).
The authors of this review point to four areas where snoezelen can be applied:
- Reducing maladaptive behaviors and increasing positive ones (Baker 2001; van Diepen 2002; Hope 1998; Long 1992).
- Increasing mood and affective state (Baker 2001; Cox 2004; Pinkney 1997).
- Facilitating interaction and communication (Spaull 1998).
- Improving the caregiver-patient relationship and decreasing stress (McKenzie 1995, Savage 1996).
The use of “snoezelen” presents variations that hinder its evaluation and comparison. These variations occur in the form, principles, duration and groups of subjects. Some researchers carry out structured programs (Baillon 2005), and others based on subjects’ preferences (van Weert 2005). Research can be found based on the daily application of “snoezelen” (van Veert 2004; van Veert 2005), or in combination with physical exercise programmes (Heyn 2003) and even residential gardening activities (Cox 2004).
Other variations are also presented in the evaluation instruments. Baker (2001) uses a behavioral rating scale. Baillon (2005) uses physiological parameters, such as heart rate monitoring.
For this reason, Chung and Lai conduct this review with the aim of examining the efficacy of “snoezelen” in people with dementia. Two studies are included for this review, with a total of 246 subjects: 122 in the “snoezelen” group and 126 in the control group (Baker 2003; van Veert 2005). While Baker’s study used scheduled sessions, van Veert’s study integrated snoezelen into daily care.
Baker’s study has certain limitations. It includes 50 subjects from an earlier study (Baker 2001), so researchers may be influenced by earlier results. It also presents differences between the three centers where the “snoezelen” programs were carried out. The centres in the United Kingdom only provided daily care, while in Sweden and the Netherlands they were psychogeriatrics centres. In addition, a different outcome measurement scale was used in each country. This made the validity and reliability of these analyses even more difficult. Finally, no significant effects on behaviour, mood, cognition, physiological parameters nor the patient-caregiver relationship were observed in the different measurements.
On the contrary, van Veert’s study showed some significant improvements in behaviour, mood and patient-caregiver communication. However, most of these improvements were acute effects, i.e., they only occurred during the sessions. In addition, there were certain limitations. One was the inclusion of a new group of patient-caregivers, due to numerous withdrawals in the middle of the program. The second was the reduced duration of treatment for this new group.
The authors of this review did not consider these studies adequate for three reasons. First, lack of robustness to the detriment of obtaining a large sample. Second, lack of methodological rigour. Finally, a focus on measuring changes in general symptoms, rather than the assessment of general performance.
Therefore, there is no scientific evidence of the efficacy of “snoezelen” in people with dementia. Snoezelen session programs are easier to apply and structure. However, they are limited by their frequency, intensity, and duration. Integration programs in daily care are more effective, but material and human resources are needed to carry them out. For future research, the authors propose:
– Greater methodological rigour.
– Programs comparable to each other.
– Recruitment criteria and similar evaluation tools.
– Provide information on the stage of dementia in which it is shown.
– More research examining long-term effects.
– Research and development of instruments to measure the patient-caregiver relationship.