October 2006

Allergic asthma, antibiotic use and chiropractic

by Robert H. Blanks, PhD, President, RCS

Childhood and adult asthma are serious health concerns. An estimated 10‑12% of children under the age of 18 years are affected by childhood asthma, making this condition the primary cause of hospitalization of children in America. The American Academy of Asthma Allergy and Immunology reports that every year asthma accounts for:

***  1.8 million emergency room visits

***  $14 billion in medical expenses and indirect costs

***  Approximately 5000 deaths

***  100 million days of restricted physical activity for children and adults

***  14.5 million missed days of work for adults

***  14 million missed days of school, making asthma the largest single cause of absenteeism

Asthma is caused by inflammation in the respiratory system and is known to have both genetic and environmental risk factors. Allergic asthma is the most common form of asthma, which is triggered by environmental allergens including cigarette smoke, dust mites, pet dander, pollens, molds, etc.

The allergens trigger an immune response in susceptible individuals mediated by IgE antibodies released by immune cells. IgE triggers the release of secondary inflammatory agents including histamine and proinflammatory cytokines that cause the inflammation, swelling of the airway and restriction of the airway.

Antibiotic use and asthma

There is an increase in antibiotics use children in group child care [1] and a high rate of inappropriate prescribing for viral infections of the middle ear, bronchitis, upper respiratory track for which antibiotics are ineffective. [2,3]

A recent publication in CHEST [4], the peer‑reviewed journal of the American College of Chest Physicians, summarizes the association between antibiotic exposure during infancy and the development of childhood asthma.

It concluded: "Exposure to a least one course of antibiotics in the first year of life appears to be a risk factor for the development of childhood asthma."

Using meta‑analysis, these researchers reviewed four prospective and three retrospective studies. In this review of 12, 082 children and 1,817 asthma cases, they found that infants who were exposed to at least one series of antibiotics were twice as likely as unexposed infants to develop childhood asthma (ages 1‑18).

The correlation between antibiotic use and asthma was significantly higher in retrospective studies (odds ratio 2.82) than in prospective studies (odds ratio 1.12).

Further, an analysis from five other published studies (27,167 children, 3,393 asthma cases) revealed the chances of having asthma increased 16% with every additional course of antibiotics given during the first year of life.

Again, this association was stronger for studies that were retrospective than for prospective studies.

Although these studies raise serious concerns about antibiotic use in young children, the researchers point out that a cause‑effect relationship cannot be established because of the possibility of "reverse causation."

The confounding issue of reverse causation might be operational were asthmatic patient to have more upper respiratory infections and thereby require more antibiotics. Nonetheless, the strong potential for concern over antibiotic use is there.

Treatment of asthma

Once asthma and allergies develop, the traditional medical treatments are antihistamines, steroids, inhalants for dilation of the airway and allergen avoidance. These approaches are a concern long‑term because they largely address the symptoms and not the cause. Medical authorities are expressing growing concern about the long‑term risk of steroids that act as immune suppressors and airway dilator medications.

As all DCs know, chiropractic offers another approach for treatment of asthma and allergic reactions in general. A number of chiropractic studies, including several randomized clinical trials [5,6] document the association between asthma symptoms and misalignment of the spine segments.

In other studies, researchers found spinal adjustments to produce improved patient self‑reported improvement and non‑specific bronchial hyper‑reactivity but no change in respiratory function. [7,cf.8] The most important and yet unresolved issue is whether the noted benefits can be confirmed in a large sample clinical trial.

Such a critical study is being conducted in chiropractic, and the timing could not have been better. A major study funded by the Foundation for Chiropractic Education and Research (FCER) has been underway for several years. Stimulated by a poorly designed medical trial [7] of active and simulated chiropractic published in the New England Journal of Medicine,  the FCER launched a carefully designed study to evaluate the effects of several well‑proven adjusting techniques on asthma.

The trial is being conducted through Macquarie University College of Chiropractic in Australia and is examining any asthmatic patient over the age of eight. The principal investigator, Ray Hayed, PhD, is evaluating patients at 16 treatment centers in Australia in an effort to find out what effects spinal manipulation has on symptoms of depression and anxiety, general health status, and the levels of immunity as measured an immunoglobulin (IGA) and immunosuppressant (cortisol).

Preliminary results were presented at the 9th International Conference on Spinal Manipulation in Toronto. Results suggest that patients receiving chiropractic show significant improvement is asthma symptoms, depression and anxiety scores. Moreover, these patients showed dramatic increases of IgA and decreases of cortisol post‑treatment, indicating secondary effects of the adjustment on the immune and endocrine system that would protect against subsequent asthmatic attack.

Another update states "it appears that the chiropractic adjustment not only improves respiratory biomechanical function, but is also having wider physiological effects. The adjustment is most likely setting up a reflex pattern within the central nervous system mediated by the spinal cord and leading to changes in the hypothalamo‑pituitary‑adrenal (HPA) axis (the pathway that leads to changes in cortisol levels)." (http://www.pr.mq.edu.au/macnews/showitem.asp?/ItemID=180).

These are extremely exciting findings, and the researchers at Macquarie are to be commended for conducting such a timely and important clinical trial.

No doubt the final study results will confirm the importance of chiropractic on not only musculoskeletal system but also on promoting general health and well‑being through activation of the immune system and HPA axis.

We all know the power of the chiropractic lifestyle, but it only through well‑designed and conducted research that we can generalize the concepts and principles of the chiropractic and ultimately impact public health policy.

The chiropractic profession will need to conduct follow‑up clinical studies specifically on childhood asthma. Other research is needed to systematically follow a large cohort of asthma patients undergoing chiropractic care.

The researchers who conducted the medical study published in CHEST suggested that the problems they encountered ‑‑ including reverse causation and control for the type of antibiotics used, etc. ‑‑ need to be overcome in further large‑scale, database‑related studies to definitively answer whether or not antibiotic use early in life is associated with later asthma risk. This is one of the long‑term objectives of the RCS research agenda.

References

1. "Who's minding the kids? Child care arrangements." Washington, DC: US Census Bureau, 1997. Available at: www.census.gov/prod/2002pubs/p70‑86.pdf.

2. Schappert SM. "Office visits for otitis media: United States, 1975‑90." Adv Data 1992; 1‑19.

3. Nyquist AC, Gonzales R, Steiner JF, et al., "Antibiotic prescribing for children with colds, upper respiratory tract infections, and bronchitis." JAMA 1998;279:875‑877.

4. Marra F, Lynd L, Coombes M, Richardson K, Legal M, FitzGerals JM, Marra C. "Does antibiotic exposure during infancy lead to development of asthma?" CHEST 129; 610‑618, 2006.

5. Bronfort G, Evans RL, Kubic P, Filkin P. "Chronic pediatric asthma and chiropractic spinal manipulation: a prospective clinical series and randomized clinical pilot study." J Manipulative Physiol Ther 2001;24 (6):369‑77.

6. Nielson NH, Bronfort G, Bendix T, Madsen F, Weeke B. "Chronic asthma and chiropractic manipulation: a randomized clinical trial." Clin Exp Allergy 1995; 25(1):80‑8.

7. Balon J, Aker DP, Crowther ER, Danielson C, Cox GP, O'Shaughnessy D, Walker C, Goldsmith CH, Duku E, Sears MR. "A comparison of active and simulated chiropractic manipulation as adjunctive treatment for childhood asthma." New Eng J Med 1998; 339(15):1013‑1020.

8. Hondras MA, Linde K, Jones AP. "Manual therapy for asthma." Cochrane Database Syst Rev 2002;1:CD001002.