Lifetime prevalence of Bell's palsy in rural Bolivia: a door-to-door survey.

We carried out a door-to-door survey in rural areas of the Cordillera Province, Bolivia, to determine the prevalence of the most common neurological diseases in a sample of about 10,000 inhabitants. A team of non-doctor health workers administered a standard screening instrument for neurological diseases, a slightly modified version of the World Health Organization protocol. All subjects found positive at the screening phase underwent a complete neurological examination. On screening, we found 1,130 positive subjects, of whom 909 were aged 15 years and above. After the neurological examination, we found 52 cases who had experienced Bell's palsy during their life in the population aged 15 years and above. The lifetime prevalence on November 1, 1994 was 11.1/1,000 (95% confidence interval 7.8-14.5) for the population aged 15 years and above. The prevalence was higher in women than in men (13.7 and 8.7/1,000, respectively) and increased with age, reaching a peak in the group aged 65 years or more (31.7/1,000). Only 3 cases (5.8%) had received medical therapy.