Sleep habits and complaints of adults in the city of São Paulo, Brazil, in 1987 and 1995

This study compares the prevalence of complaints of insomnia, excessive diurnal sleepiness, parasomnias, and sleep habits of the adult population in the city of São Paulo, Brazil, estimated in surveys carried out in 1987 and 1995. Representative samples of 1000 adult residents per survey were interviewed using a validated structured sleep questionnaire, the "UNIFESP Sleep Questionnaire". Difficulty maintaining sleep, difficulty initiating sleep and early morning awakening, occurring at least three times a week, were reported in 1987 and 1995, by 15.8/27.6, 13.9/19.1, and 10.6/14.2 percent of the interviewees, respectively, significantly increasing throughout time. These sleep problems were more often found among women. Frequencies of excessive diurnal sleepiness and sleep attacks were unchanged comparing 1987 with 1995 (4.5 vs 3.8 and 3.1 vs 3.0 percent, respectively). Parasomnia complaints remained unchanged, with the exception of leg cramps, which doubled in prevalence from 1987 to 1995 (2.6 to 5.8 percent). Snoring was the most common parasomnia (21.5 percent in 1995), reported more often by men than by women, and somnambulism was the least common (approximately 1 percent). Besides sleeping slightly less, interviewees went to bed and woke up later in 1995. Approximately 12 percent of the subjects in both surveys had consulted a physician due to sleep problems and 3.0 percent reported habitual use of sleep-promoting substances in 1995. Overall, there was a significant increase in insomnia complaints from 1987 to 1995 in the general population of the city of São Paulo. This major change over a little under a decade should be considered as an important public health issue.

A comparison of public and private obstructive sleep apnea clinics

The aim of the present study was to compare the clinical findings and polysomnography results obtained at public and private clinics in Brazil, the follow-up after diagnosis, and the therapeutic aspects related to continuous positive airway pressure. Patients who snore and who have obstructive sleep apnea were retrospectively divided into two groups, i.e., public clinic (N = 307) and private clinic (N = 317). Data concerning age, sex, body mass index (BMI), neck circumference, medical history, sleepiness scale, follow-up after diagnosis, and acceptance of continuous positive airway pressure therapy were collected. Mean age was 50 ± 12 (range: 15-80) for public patients and 48 ± 12 years (range: 19-91) for private patients. Mean BMI was 30 ± 6 (range: 19-67) for public patients and 31 ± 6 kg/m² (range: 21-59) for private patients. The public clinic had a significantly higher frequency of women than the private clinic (M:F ratio of 2.0:1 and 6.9:1, respectively). The condition of private patients (apnea-hypopnea index = 31 ± 25) was more severe than that of public patients (apnea-hypopnea index = 25 ± 24 events/h; P = 0.0004). In the public and private clinics, 19 and 15 percent of patients were snorers, respectively, and 81 and 85 percent of them had sleep apnea. After diagnosis, follow-up was longer in the private group. The continuous positive airway pressure acceptance was similar for both groups (32 vs 35 percent), but patients from the public clinic abandoned treatment more than private ones (65 vs 13 percent). Social status was significant in terms of the severity of obstructive sleep apnea age and gender distribution. Private patients look for a diagnosis earlier in the course of the disease than public patients, adhere more to follow-up, and abandon continuous positive airway pressure treatment less than public patients do.

Becoming circadian: a one-year study of the development of the sleep-wake cycle in children

Data on three children's sleep-wake behavior during the first year of life submitted to spectral analysis reveal the presence of several frequencies in the circadian and ultradian ranges. The changes in the resulting spectra as age progresses show both an increase in overall rhythmicity, i.e., more data are explained by regular oscillations, and irregular changes in the circadian component. This circadian component shows an increase in power which appears at different ages among the individuals studied.