Discussion
diabetes-related complications, glucose intolerance, insomnia, diabetes
GLUCOSE INTOLERANCE, TYPE 2 DIABETES, DIABETES
The results of this study showed that laughter yoga program for 12 weeks decreased HbA1c levels in individuals with type 2 diabetes. Additionally, the high attendance rate suggests that the program is feasible for the participants. To the best of our knowledge, this is the first randomized controlled trial that has evaluated the long-term effects of laughter yoga on glycemic control in individuals with type 2 diabetes.The findings of the current study are consistent with previous studies demonstrating that laughter by watching a comedy show for 40 min (The mean HbA1c levels changed from 7.07% to 6.82% in the laughter yoga group. Recent study has shown that maintaining HbA1c levels at <7% over 5 years is associated with significant reductions in the odds of being diagnosed with diabetes-related complications (A meta-analysis found that, in individuals with type 2 diabetes, low-to-moderate-intensity resistance exercise reduced HbA1c levels by 0.23%, and high-intensity resistance exercise reduced HbA1c levels by 0.61% (Although the mechanisms remain unclear, there are several possibilities for the effect of laughter yoga on diabetes. First, it has been reported that laughter upregulates genes related to natural killer cell activity in individuals with type 2 diabetes, which may ameliorate glucose intolerance (It has been reported that when people experience positive affect during a specific behavior, they are more likely to continue that behavior (In this study, sleep duration tended to improve. This finding is consistent with previous studies reporting that laughter has favorable effects on sleep quality or insomnia. One study has shown that 1 h of laughter therapy once a week for 4 weeks improves insomnia and sleep quality among older individuals (Laughter yoga combines simulated laughter with yoga breathing techniques. The effects of laughter and the effects of yogic breathing are difficult to distinguish because laughter also consists of mixed patterns of expiration, inspiration, and interval pauses (This study conducted a 12-week laughter yoga intervention. In a systematic review of the effects of laughter-inducing interventions, the duration of most laughter yoga interventions ranged 4 to 8 weeks and one study conducted a 12-week laughter yoga intervention (In this study, we did not assess the sustainability of the effects of the intervention after the study period. Further follow-up studies are needed to examine how long the effects of laughter yoga are maintained. A meta-analysis showed that improved physical activity through behavioral change interventions is generally not sustained after the intervention (This study has several limitations. First, the number of participants was small, and the study was conducted in a single center. Multicenter studies with larger sample sizes are needed to better understand the intervention’s efficacy and generalizability. The study participants were all Japanese living in an urban area and outpatients of the university hospital with relatively good glycemic control. Our findings may not apply to different populations, including other ethnic groups, those living in rural areas, and those with poorly controlled type 2 diabetes. Further studies are needed to evaluate the effects of laughter yoga on glycemic control in different populations. In contrast, the effects of laughter yoga on mental health have been reported worldwide (Asia, the Middle East, Australia, and United States) and in different clinical settings (In conclusion, laughter yoga for 12 weeks decreased HbA1c levels in individuals with type 2 diabetes, and the program is feasible with a high attendance rate. The importance of psychological well-being in individuals with diabetes has been gradually recognized, and positive psychological interventions have been recommended (