Capsaicin troche for swallowing dysfunction in older people

OBJECTIVES: To determine whether oral capsaicin troche supplementation with every meal upregulates the impairment of upper respiratory protective reflexes such as the swallowing reflex and the cough reflex. DESIGN: Randomized, controlled study with recruitment through nursing homes. SETTING: Sendai, Japan, from September 2002 through December 2003. PARTICIPANTS: Sixty-four participants in nursing homes with a mean age +/- standard deviation of 81.9 +/- 1.0 with stable physical status. INTERVENTION: Participants were randomly assigned to the program for the supplementation of capsaicin trochisci or placebo trochisci before every meal for 4 weeks. MEASUREMENTS: Assessment of individual latency time of the swallowing reflex (LTSR) and cough reflex sensitivity. RESULTS: Before the commencement of this study, there were no significant baseline differences in multiple parameters between the intervention group and control group. LTSR in participants in the intervention group was significantly shorter than in the control group (P <.05). The odds ratio (OR) of the shortening of the LTSR of more than 1 minute in the intervention group was 3.4 (95% confidence interval (CI)=1.1-10.4), compared with the control group (P=.03). In particular, daily capsaicin supplementation significantly increased the ratio of LTSR reduction at 4 weeks after the study to baseline LTSR in the high-risk group (baseline LTSR > 6.0 seconds) compared with the low-risk group (baseline LTSR < 3.0 seconds) and the intermediate group (3.0 seconds < baseline LTSR < 6.0 seconds) (P <.005). Seventeen (52.1%) participants in the intervention group and seven (21.9%) in the control group showed improvement in cough reflex sensitivity (OR=4.1, 95% CI=1.4-12.2; P <.01). CONCLUSION: Daily capsaicin supplementation resulted in a significant improvement in upper protective respiratory reflexes, particularly in older people with a high risk for aspiration.