The Effect of Simultaneous Variations of Humidity and Barometric Pressure on Arthritis

Since the time of Hippocrates, medical writings have contained references to the effect of weather on human diseases, particularly arthritis and rheumatism. Most arthritic patients claim that they feel worse before weather changes. This sensitivity to climatic variations has defied scientific corroboration or explanation mainly because of a lack of facilities to control weather factors and observe arthritic patients under completely controlled, climatic conditions for significant periods of time. In 1948, Edstrom showed that arthritic patients were improved by continuous habitation in a climate chamber with constant warm temperature and moderate humidity. His experiments did not include any variations of climate factors, nor was there control of barometric pressure, air ionization, or rate of air flow [1]. In an effort to study objectively the effect of climatic variations on arthritis, a Controlled Climate Chamber was designed and constructed in the Hospital of the University of Pennsylvania to comfortably house two patients for observation periods of two to four weeks. Temperature, humidity, rate of air flow, barometric pressure, a :d air ionization are continuously controlled and recorded, and may be varied accurately by prescribed patterns without the knowledge of the patients. The construction of the Climatron and the description of the apparatus and method of experimentation have been previously reported [2, 3]. (See Fig. 1.) The general concept of the experimentation has also been set forth elsewhere