Study shows laughter helps difficult-to-control RA

Researchers have found that a good laugh has a positive effect on the immune response of patients with severe rheumatoid arthritis (RA) The findings point to the importance of addressing not only the physical but also the psychological stresses of severe RA. “The effects of mirthful laughter might be remarkable, especially in the difficult-to-control RA group, since it is thought that such patients are under much more psychological and physical stress in daily life compared with patients with easily controlled RA,” comment the researchers, led by Dr T Matsuzaki (Nippon Medical School, Tokyo, Japan). Their study appears in the February 2006 issue of Rheumatology.

The researchers studied the effect of laughter on serum pro- and anti-inflammatory cytokines. They looked at 41 RA patients and 23 healthy subjects. The RA patients were divided into two groups, difficult-to-control and easily controlled. Patients with severe RA had a C-reactive protein of >1.0 mg/dL.Subjects listened to a traditional Japanese story called Rakugo that is known to be very funny. The researchers measured pro- and anti-inflammatory cytokines before and after the story was played. They observed that the baseline levels of serum interleukin-6 and TNF- in the RA patients were significantly higher than those in the healthy group. After laughing, the RA group’s levels of serum interleukin-6 decreased significantly, but not those of the healthy subjects. A similar effect was found for interleukin-4. RA patients had significantly higher concentrations at baseline, but these levels dropped after they laughed at the story. “These results suggest that not only the immunological process but also psychological condition regulates the production of several cytokines in RA.” In contrast, serum interleukin-1 receptor antagonist was statistically higher in the RA group than in healthy subjects at the start of the study but continued to increase after the funny story- especially in the easily controlled RA group. Interestingly, the level of serum TNF- decreased only in this same group- the milder-RA patients. The researchers write that consistent with previous reports, their study demonstrates that abnormal levels of serum pro- and anti-inflammatory cytokines were present in RA patients at baseline. “After laughter, these molecules were differentially modulated depending on the disease activity of RA,” they report. “These results suggest that not only the immunological process but also psychological condition regulates the production of several cytokines in RA.”Evidence emerging on the effect of stress on the immune systemMatsuzaki and colleagues note that the effect of stress on cytokine production is generally not well understood. But they point to mounting evidence suggesting that an interaction between stress and the immune system plays a pivotal role in the etiology and progression of autoimmune diseases such as RA.”These findings suggest the possibility that the various immunomodulatory responses to mental condition depend on the disease activity of RA,” the researchers write. “Therefore, psychological support should be considered indispensable for the treatment of RA.”Another recent study examining the health effects of laughter came to a similar conclusion [2]. Researchers led by Dr Michael Miller (University of Maryland, Baltimore) found that humour boosts endothelial function. The group reports that regularly watching comedies or doing other activities that encourage laughter has the potential for being a safe, risk-modifying intervention for people with impaired vasoreactivity. (Sources:Matsuzaki T, Nakajima A, Ishigami S, et al. Mirthful laughter differentially affects serum pro- and anti-inflammatory cytokine levels depending on the level of disease activity in patients with rheumatoid arthritis. Rheumatology 2006; 45:182-186. Miller M, Mangano C, Park Y, et al. Impact of cinematic viewing on endothelial function. Heart 2006; 92:261-262. Joint and Bone: February 2006.)