Impact of the Olfactory Stimulation on the People With Mild Dementia Via the Horticultural Therapy

A registered nurse drew 5 cc of blood from each participant twice, including pretest and posttest by the following procedure:

Step 1: Plasma preparation 10-ml K3 EDTA tubes were used for collecting blood, immediately followed by gently inverting each blood tube 10 times. Blood tubes were centrifuged at room temperature at 2500g for 15 minutes with an aid of a swing-out (backet) rotor. Every 1-ml plasma (supernatant) was transferred to a fresh 1.5-ml eppendorf using a disposable 1-ml micropipette tip. All the plasma samples were frozen at -80 °C before measurements.

Step 2: Assays of plasma biomarkers IMR kits were used in assaying amyloid B 1-42 and tau protein (Tau). For assaying AB1-42, 60-ul reagent was mixed with 60-ul plasma. For assaying Tau, 80-ul reagent was mixed with 40-ul plasma. Duplicated measurements were conducted for each biomarker per plasma sample. The average value of the duplicated measured concentrations is reported.

All the participants were received the interview of MMSE twice, including pretest and posttest. A trained research assistant performed the test face to face. The MMSE is a widely used tool for clinical evaluation, with five major domains (orientation, registration, attention and calculation, recall, language). The examination is composed of 11 questions; the score ranges from 0 to 30, with a higher score indicating better cognitive function.

All the participants were received the interview of LOTCA-G twice, including pretest and posttest. A trained research assistant performed the test face to face. The LOTCA-G, a modified version of the LOTCA for adults aged >70 years or for clients with a slower response to cognitive tasks, contains 23 subsets in 7 cognitive areas (orientation, visual perception, spatial perception, praxis, visuomotor organization, thinking operations, memory). Each question is scored from 1 (severe deficit) to 4 (average performance), with scores ranging from 23 to 100, with higher scores indicating better cognitive performance (Erez & Katz, 2004). LOTCA-G, a well-established test of discriminant validity for individuals with dementia, can be used to monitor changes in cognitive function during an intervention.

All the participants were received the interview of TIBSIT twice, including pretest and posttest. TIBSIT, which consists of 16 tests (1 odor for 2 repeated tests) and a questionnaire, has 8 odors relevant for the Taiwanese population. Each participant completed the test with the assistance of a trained research assistant, if necessary. Within a test, the participant scratches the paper off the fragrant microcapsules using a pencil, smells the fragrance, and then answers two questions. The first question is a single choice from among four answers to identify the closest name of the odor, and the second is a three-item choice of not detectable (smell nothing, 0 points); detectable, but not sure (can smell something but unsure, 1 point); and detectable (can smell and know exactly what it is, 2 points). A total of 48 points are available for 16 tests.

All the participants were received the interview of GDS-15 twice, including pretest and posttest. A trained research assistant performed the test face to face. GDS-15, a 15-item, short, easy-to-conduct questionnaire, to assess participants' emotional changes during the intervention. The answers are reported on a yes-no scale; the total scores range from 0 to 15, with higher scores indicating more severe depression.