Effectiveness of a Multisensory Stimulation Intervention on Neuropsychiatric Symptoms in Moderate to Advanced Dementia: a Randomized Controlled Clinical Trial

Background: Neuropsychiatric symptoms (NPS) in people with dementia frequently evolve with progression of the disorder. Nonpharmacological interventions are the first-line treatment to control NPS in dementia. Multisensory stimulation (MSS) is a nonpharmacological intervention that is conducted by stimulating one or more of the five senses of the body with pleasant sensory experiences. This work aims to investigate the effects of a MSS protocol in elderly people with moderate to advanced dementia living in long-term care institutions in Brazil.

Methods: A specific MSS protocol was developed by the researchers for the study. Sixty elderly people with moderate to advanced dementia (Clinical Dementia Rating of 2 or 3 and a Mini-Mental State Examination score ≤17) were randomly allocated to intervention (n=30) and control (n=30) groups. The sample size estimation was established with a paired bilateral t-test with a 0.05 significance level. This sample size would have 80% power to detect a mean difference of 9.50 in the NPI scores from pre- to post-intervention and a standard deviation of 17.28, as proposed by Fu et al. (2013). The intervention group participated in 16 individual 30-minute sessions over eight weeks in a quiet room, and the control group received usual care.

The MSS program includes eight sessions. During these sessions, the five body senses (sight, taste, hearing, smell, and feeling) are stimulated using songs, fruits, fiber optic lamps, natural scents, among other stimuli, to promote interactions between the participants and the therapist, as well as the objects. In each session, at least two senses are stimulated in a safe, quiet and confidential environment. The sessions last 30 minutes and are conducted twice a week, on the same day and time whenever possible. Nonetheless, the session can be interrupted when the participant wishes or if the therapist observes that the patient is uncomfortable. A nondirective approach and one-to-one intervention were adopted.The MSS protocol was conducted by an occupational therapist. In this study, the eight-session protocol was used twice, that is, the protocol was repeated from the ninth session forward, but the protocol was customized for each participant by consideration of the participants' interests in previous sessions and the protocol rules.