Pneumonia is a common cause of morbidity and mortality worldwide. The wide use of vaccines and anti-microbial treatments have substantially reduced the rate of death from infectious disease;however, the prevalence of organisms resistant to vaccines and antimicrobial therapy have increased substantially in recent years, raising the possibility that these treatments will become less effective in the future.26,27
Therefore, there is a growing need to investigate the effectiveness of alternative therapies for the treatment of infectious disease.
LPT has been used as an adjunctive therapy to improve cleansing of the tracheobronchial tree, increasesputum production and shortenthe duration of coughin patients with lower respiratory tract disease.16,17
Recently, the multi-center osteopathic study in the elderly (MOPSE) conducted a double-blinded randomized, controlled trial to measure the efficacy of osteopathic manipulation as an adjunctive treatment for hospitalized elderly patients with pneumonia.18
Within 24 hours of admission,subjectswere randomised into conventional care, conventional care plus light-touch, or conventional care and OMT. Conventional care consisted of treatment for pneumonia as directed by their attending physicians.OMT or light-touch treatments were applied to patients supine in bedtwice daily (≥ six hours apart) for 15 minutes and continued until hospital discharge, cessationof antibiotics, respiratory failure(ventilator dependent), death, or study withdrawal. OMT was applied in the following sequence: thoracolumbar soft tissue, rib raising, doming of the diaphragm myofascial release, cervical spine soft tissue, suboccipital decompression, thoracic inlet myofascial release, thoracic LPT with activation, and pedal LPT. Soft tissue techniques consisted of massage, stretching, kneading, and direct inhibitory pressure to relax the musculature. Non-thrust techniques were used to treat areas unaddressed by the above techniques and were limited to ≤ 5 minutes. The light touch treatment imitated theOMT protocol, generally touching thesame areas treated with OMT for the same duration. Self reported side effects were mild (post-treatment musculoskeletal soreness or pain), but significantly (P= 0.003) higher in the OMT group.
Primary clinical outcomes measured were the length of hospital stay, time of clinical stability and pneumonia-specific symptomatic and functional recovery scores. Secondary outcomes measured were the duration of oral and intravenous antibiotics, treatment endpoint (including respiratory failure or death), hospital readmission rate, daily body temperature, daily respiratory rate and white blood cell counts (WBC).
A total of 406 subjects were utilized for the study. There were no significant differences between groups on compliance with antibiotic treatment guidelines and clinical measures, which included comorbidities and pneumonia severity. Intention-to-treat analysis found no significant difference between the groups for any outcome. However, per-protocol analysis found OMTplus conventional care decreased in length of hospital stay, the duration of intravenous antibiotics respiratory failure or death compared to the conventional care group alone.This result suggests that OMT is protective against pneumonia if a patient received the protocol as prescribed, without missing any treatment. It is important to acknowledge that intention to treat analysislikely reflects actual clinical conditions.
Of interest, the authors also found that light-touch outcomes generally fell betweenOMT and conventional care, but were not significantly different from either, suggesting the therapeutic effects of OMT and light-touch overlap. In support, light touch in rats excites the nervous system.28
Furthermore, touch therapy has been used clinically for pain relief.29
These findings suggest that light touch stimulates the nervous system, which may benefit patients in pain. However, the clinical benefits of light touch, if any, are not clearly defined.
Enhancing the lymphatic release of leukocytesmay explain, in part, how LPT improves clinical outcomes in patients with infectious disease, such as pneumonia. To determine if LPT would facilitate the clearance ofpulmonary bacteria,the laboratory of LM Hodgeapplied LPT to rats using a pneumococcal pneumonia disease model.30
This study was approved by the Institutional Animal Care and Use Committee at the University of North Texas Health Science Centre and conducted in accordance with the Guide for the Care and Use of Laboratory Animals (NIH Publication no. 85-23, revised 1996). Sixty male JVC Fischer 344 rats (Charles River Laboratories, Wilmington, MA) weighing 250–300g, and free of clinically evident signs of disease were used for this study. Rats were fed a standard laboratory diet and allowed to eat and drink ad libitum
Rats were nasally infectedwith 1 × 108Streptococcus pneumoniae
(kindly provided by Dr. Jerry Simecka at the University of North Texas Health Science Center, Fort Worth, Texas) colony forming units (CFU) as previously described.31
Twenty-four hours after infection, rats were divided into control (N=20), sham (N=20) or LPT (N-20) treatment groups. For seven consecutive days rats received either 1) A daily sham treatment consisting of intravenous administration of 10mg/kg propofolanaesthesia followed by four minutes of light touch, 2) Four minutes of LPT daily under propofolanaesthesiaor 3) No treatment or anaesthesia (control). The application of LPT to the rats was performed as previously described.12
Briefly, anesthetized rats were kept in a right lateral recumbent position. To perform LPT, the operator (Kyle Gummelt, D.O.) contacted the abdomen of the rat with the thumb on one side and index finger and middle finger on the other side of the medial sagittal plane. The fingers were placed bilaterally caudal to the ribs. Sufficient pressure was exerted medially and cranially to compress the lower ribs until significant resistance was met against the diaphragm, then the pressure was released. Compressions were administered at a rate of approximately one/second for the duration of the four minutes of treatment. During sham treatment, rats were anesthetized and the operator contacted the abdomen of the rat for four minutes in a manner similar to LPT; however no compressions were made.
Eightdays after infection, lungs were collected and measured for S. pneumoniae
bacteria and the concentration of immune cells as previously described.12,31,32,33
Data from control, sham and LPT treatment rats were analyzed by analysis of variance (ANOVA) followed by a Tukey multiple comparisons post test using Graphpad Prism version 5.0 for Windows, (GraphPad Software, San Diego, CA). Differences among mean values with P £ 0.05 were considered statistically significant.Data are presented as arithmetic means ± standard error (SE).
Both LPT and sham treatment reduced bacteria in the lungs compared to control (); however, LPT cleared more bacteria compared to sham treatment. During the eight days of infection, control rats were unable to clear bacteria from their lungs at any time point.It is plausible that the propofolanaesthesiaadministered toboth the LPT and sham treatment groupsprovided a protective effect during pneumonia. In support, propofol has been shown to protect againstacute lung injury in rats by abrogating the microvascular leakage of water and protein in the lungs and suppressing oxidative and other inflammatory-mediated injuries.34, 35
Also, light touch may have enhanced protection against pulmonary infection, though the mechanism is uncertain.Importantly, LPT significantly (P<0.01) reduced bacterial numbers compared to sham, suggesting LPT induces either a separate or additive protective mechanism compared to sham alone.
LPT reduces Streptococcus pneumoniae colony forming units during acute pneumonia
It was not surprising that LPT and sham treatment rats had fewer immune cells in their lungs since infection was subsiding in these rats ().Immune cells are known to traffic into the lung during inflammation36
and leukocytes have been shown to quickly increase in blood and lung tissue in response to pneumococcal pneumonia;37
therefore, It is possible that LPT may have increased the numbers of immune cells trafficking into the lungs at an earlier time (after just a few treatments), which was sufficient to reduce bacterial numbers, thereby reducing immune cellswithin the lungs by eight days post-infection. It is also likely that this protection is not solely immune cell mediated. For example,LPT may have enhanced the concentration of pulmonary antimicrobial products such as surfactant proteins, defensins, lysozyme and lactoferrin. In addition, LPT may have enhanced respiratory ciliary beat, cough reflex, and mucus clearance. Future experimentation isrequired to identify the LPT-mediated protective mechanism(s) in this diseasemodel.
Pulmonary immune cell numbers in rats with acute pneumonia
It is interesting that LPT offered the greatest protection and sham treatment offered intermediate protection against pneumonia in rats. This finding is consistent with the clinical outcomes seen in the MOPSE study and suggests that OMT, and in particular LPT, may enhance the clearance of bacteria in patients with pneumonia. It also suggests that light touch has a therapeutic effect. It is important to note that these animal studies focused specifically on LPT, whereas the clinical trial utilized many osteopathic techniques, including LPT. There are also obvious differences between the application of LPT in humans and animals, which is an inherent flaw in using animal models to study the mechanisms of human manual medicine treatments. Also, unlike humans, to apply LPT and light touch (sham treatment), rats were placed under anaesthesia, which may have augmented host defences during infection. Nonetheless, this study demonstrates that the rat is a useful model to study the therapeutic effects of LPT. Also, animal models provide data that cannot be obtained from humans and may provide insight into the mechanisms by which LPT enhances the lymphatic and immune systems and protects against infectious disease.