To the Editor:
We read with interest the recent report from Peláez-Ballestas, et al1 related to the epidemiology of rheumatic disease in Mexico, which included 5 regions. Most of the study population was from urban areas, which could make the study not as exact as desirable. The findings are similar to our data from the city of San Luis Potosí, population 2,410,414, located in the center of the country2. Working with medical students of the Rheumatology Course, we made a questionnaire survey including 26,691 subjects with the purpose of identifying the principal rheumatic diseases. Our principal demographic differences were the mean education time (12 years) and a high prevalence of rheumatoid arthritis (2.6%)3. In spite of this, we would emphasize that in general, the population in our country is diverse and heterogeneous, and that there are many differences between states or regions. These differences are even greater among states, making it difficult to define the real prevalence of rheumatic diseases. An example is Yucatán, with a higher indigenous population (966,787)2. Even the state of San Luis Potosí has various indigenous zones, e.g., the primary Huasteca (tropical zone) and altiplane zone (desert): in the Huasteca zone there are Teenek, Huasteca, and Nahuatl tribal influences, and near the city of San Luis Potosí toward the Huasteca zone, the Pame is a predominant tribe4. In the desert zone, there is chichimeca culture, where Zacatecos, Copuces, Guamares, Jonacesa, and Huachichiles are prevalent. Seven out of 100 persons in Mexico speak an indigenous language/dialect and only one of 7 also speaks Spanish2. There are 173,233 persons who speak Huasteco, although Nahuatl is the most important of our diversity of dialects, numbering 1,659,0005. This language barrier limits assessment of the real prevalence of rheumatic diseases in developing countries such as Mexico.
Despite this, the importance of the data reported by Peláez-Ballestas, et al1 is evident, with some differences between regions, such as education levels, although these differences could be wider still, recognizing the diversity of the Mexican population.