Yang et al.BMC Complementary and Alternative Medicine (2015)15:93 Page 6 of 8 Table 3 Changes in the LF%,LF/HF,and HF over time in the three groups LF% LF/HF HF B(95%C) p β(95%C p β(95%C) p Group A-a group (n=50) 7.86(-0.23-15.95) 0.06 0.79(0.04-1.54） 0.04 -0.22(-1.31-0.870 0.69 A group (n=61) 0.25(-7.00-7.49 0.95 0.43(-025-1.11) 0.22 035(-0.68-137) 0.51 Control group (Reference,n=49) Time 1st week -329(-6.69-3.12) 0.32 -0.01（-0.69-0.66) 0.98 -0.20(-1.12-0.73) 0.68 2nd week 1.94(-4.51-839) 0.56 0.21(-047-0.89) 0.55 -0.16(-1.10-078 0.74 3rd week -5.68(-1263-1.27) 0.11 -0.06(-0.79-0.68) 0.87 0.06(-0.95-1.06 0.91 4th week -1.06(-7.70-5.58) 0.75 0.06(-0.64-0.76) 0.87 -0.36(-1.31-0.60) 0.47 Post-test -1.73(-886-5.39) 0.63 0.05(-070-0.80) 0.90 -0.07(-1.090.96) 0.90 Post-3 wks -077(-7.50-5.96 0.82 0.11(-0.60-0.82) 0.76 -020(-1.17-0.7) 0.69 Group x Time A-a group x 1st week -151(-11.05-8.20) 0.76 -045(-1.44-0.54 0.37 1.00(-033-2.34) 0.14 A-a group x 2nd week -8.93(-1837-0.51) 0.06 -082(-1.80-0.16) 0.10 2.91(1.60-4.23) <0.01￥ A-a group x 3"d week -938(-19.35-0.60) 0.07 -0.91(-1.94-0.12） 0.08 854(7.17-9.92) <0.01* A-a group x 4th week -1234(-2216to-2.5) 0.01* -1.09(-2.11to-0.070 0.04 5.45(4.08-6.82) <0.01* A-a group x post-test -9.90(-20.15-0.34) 0.06 -083(-1.89-0.23) 0.13 0.68(-0.76-2.11) 0.36 A-a group x post-3 wks -7.16(-1727-2.96) 0.17 -0.50(-1.55-0.55) 0.35 054(-087-1.96 0.45 A group x 1st week -539(-13.87-3.91) 0.21 -0.50(-1.39-0.40) 0.28 -0.43(-1.65-0.80) 0.49 A group x 2nd week -1209(-20.6t0-3.59) 0.01* -0.15(-1.05-0.75) 0.75 027(-0.96-1.50) 0.67 A group x 3rd week 0.39(-8.57-935) 0.93 -047(-1.41-0.48) 0.33 -0.42(-1.65-080) 0.52 A group x 4th week -5.74(-14.43-2.95) 0.20 -0.71(-1.63-0.20) 0.13 158(0.32-2.83) 0.01* A group x post-test -8.98(-1833-0.36) 0.06 -0.69-1.67-029 0.17 088(-047-222) 0.20 A group x post-3 wks -2.09(-1132-7.14) 0.57 -048(-1.46-0.49) 0.33 0.45(-089-1.78) 0.51 Note.Aroma-acupressure group:A-a group;Aroma group:A group:Cl:confidence interval;p<.05. nerves are stimulated and next somatic nerves and auto- in the aromatherapy group,HF was significantly higher nomic nerves.Stimulation of somatic nerves can cause only in the fourth week following the interventions.There- skeletal muscles to relax and stimulation of sympathetic fore,the effects of aroma-acupressure on enhancing the nervous system and parasympathetic nervous system parasympathetic nervous system appear to be stronger can cause blood vessels,internal organs,and glands to compared with aromatherapy. effect [11].For example,Hongratanaworakit explored the According to the HRV and the CMAI,aroma-acupressure relaxing effect of rose essential oil on humans when it was was better able to improve agitation,inhibit the sympathetic absorbed through skin.It was discovered that the oil could nervous system,and activate the parasympathetic nervous significantly lowered respiratory frequency,oxygen satur- system compared with aromatherapy.One explanation for ation,and systolic pressure,indicating that it could inhibit this finding is that the participants in this study were pri- sympathetic nervous system [22].In other words,effects marily AD patients.According to previous studies,AD is of both acupuncture and aromatherapy are related to often accompanied by olfactory impairment,and more autonomic nervous system and the effect of aroma- serious AD is associated with the loss of additional olfactory acupressure is superior to aromatherapy,which indicates abilities 23.As a result,the ability to absorb essential oils the combination effect of aromatherapy and acupressure may become weaker because essential oils are absorbed is larger than the use of aromatherapy alone. through transdermal administration or inhalation.Similarly, In the aroma-acupressure group,the parasympathetic ac- Snow,Hovanec,and Brandt found no support for the use tivity(HF)was significantly higher from the second week to of a purely olfactory form of aromatherapy to decrease agi- the fourth week following the interventions,which demon- tation in dementia because olfactory impairment may strates the relaxing effect of aroma-acupressure;however, weaken the effects of aromatherapy [24].nerves are stimulated and next somatic nerves and auto￾nomic nerves. Stimulation of somatic nerves can cause skeletal muscles to relax and stimulation of sympathetic nervous system and parasympathetic nervous system can cause blood vessels, internal organs, and glands to effect [11]. For example, Hongratanaworakit explored the relaxing effect of rose essential oil on humans when it was absorbed through skin. It was discovered that the oil could significantly lowered respiratory frequency, oxygen satur￾ation, and systolic pressure, indicating that it could inhibit sympathetic nervous system [22]. In other words, effects of both acupuncture and aromatherapy are related to autonomic nervous system and the effect of aroma￾acupressure is superior to aromatherapy, which indicates the combination effect of aromatherapy and acupressure is larger than the use of aromatherapy alone. In the aroma-acupressure group, the parasympathetic ac￾tivity (HF) was significantly higher from the second week to the fourth week following the interventions, which demon￾strates the relaxing effect of aroma-acupressure; however, in the aromatherapy group, HF was significantly higher only in the fourth week following the interventions. There￾fore, the effects of aroma-acupressure on enhancing the parasympathetic nervous system appear to be stronger compared with aromatherapy. According to the HRV and the CMAI, aroma-acupressure was better able to improve agitation, inhibit the sympathetic nervous system, and activate the parasympathetic nervous system compared with aromatherapy. One explanation for this finding is that the participants in this study were pri￾marily AD patients. According to previous studies, AD is often accompanied by olfactory impairment, and more serious AD is associated with the loss of additional olfactory abilities [23]. As a result, the ability to absorb essential oils may become weaker because essential oils are absorbed through transdermal administration or inhalation. Similarly, Snow, Hovanec, and Brandt found no support for the use of a purely olfactory form of aromatherapy to decrease agi￾tation in dementia because olfactory impairment may weaken the effects of aromatherapy [24]. Table 3 Changes in the LF%, LF/HF, and HF over time in the three groups LF% LF/HF HF β (95%CI) p β (95%CI) p β (95%CI) p Group A-a group (n = 50) 7.86 (−0.23-15.95) 0.06 0.79 (0.04-1.54) 0.04* −0.22 (−1.31-0.87) 0.69 A group (n = 61) 0.25 (−7.00-7.49) 0.95 0.43 (−0.25-1.11) 0.22 0.35 (−0.68-1.37) 0.51 Control group (Reference, n = 49) Time 1st week −3.29 (−6.69-3.12) 0.32 −0.01 (−0.69-0.66) 0.98 −0.20 (−1.12-0.73) 0.68 2nd week 1.94 (−4.51-8.39) 0.56 0.21 (−0.47-0.89) 0.55 −0.16 (−1.10-0.78) 0.74 3rd week −5.68 (−12.63-1.27) 0.11 −0.06 (−0.79-0.68) 0.87 0.06 (−0.95-1.06) 0.91 4th week −1.06 (−7.70-5.58) 0.75 0.06 (−0.64-0.76) 0.87 −0.36 (−1.31-0.60) 0.47 Post-test −1.73 (−8.86-5.39) 0.63 0.05 (−0.70-0.80) 0.90 −0.07 (−1.09-0.96) 0.90 Post-3 wks −0.77 (−7.50-5.96) 0.82 0.11 (−0.60-0.82) 0.76 −0.20 (−1.17-0.77) 0.69 Group x Time A-a group x 1st week −1.51 (−11.05-8.20) 0.76 −0.45 (−1.44-0.54) 0.37 1.00 (−0.33-2.34) 0.14 A-a group x 2nd week −8.93 (−18.37-0.51) 0.06 −0.82 (−1.80-0.16) 0.10 2.91 (1.60-4.23) <0.01* A-a group x 3rd week −9.38 (−19.35-0.60) 0.07 −0.91 (−1.94-0.12) 0.08 8.54 (7.17-9.92) <0.01* A-a group x 4th week −12.34 (−22.16 to −2.5) 0.01* −1.09 (−2.11 to −0.07) 0.04* 5.45 (4.08-6.82) <0.01* A-a group x post-test −9.90 (−20.15-0.34) 0.06 −0.83 (−1.89-0.23) 0.13 0.68 (−0.76-2.11) 0.36 A-a group x post-3 wks −7.16 (−17.27-2.96) 0.17 −0.50 (−1.55-0.55) 0.35 0.54 (−0.87-1.96) 0.45 A group x 1st week −5.39 (−13.87-3.91) 0.21 −0.50 (−1.39-0.40) 0.28 −0.43 (−1.65-0.80) 0.49 A group x 2nd week −12.09 (−20.6 to −3.59) 0.01* −0.15 (−1.05-0.75) 0.75 0.27 (−0.96-1.50) 0.67 A group x 3rd week 0.39 (−8.57-9.35) 0.93 −0.47 (−1.41-0.48) 0.33 −0.42 (−1.65-0.80) 0.52 A group x 4th week −5.74 (−14.43-2.95) 0.20 −0.71 (−1.63-0.20) 0.13 1.58 (0.32-2.83) 0.01* A group x post-test −8.98 (−18.33-0.36) 0.06 −0.69 (−1.67-0.29) 0.17 0.88 (−0.47-2.22) 0.20 A group x post-3 wks −2.09 (−11.32-7.14) 0.57 −0.48 (−1.46-0.49) 0.33 0.45 (−0.89-1.78) 0.51 Note. Aroma-acupressure group: A-a group; Aroma group: A group; CI: confidence interval; *p < 0.05. Yang et al. BMC Complementary and Alternative Medicine (2015) 15:93 Page 6 of 8