The increase in longitudinally measured sleepiness across adolescence is related to the maturational decline in low-frequency EEG power

OBJECTIVES: A changing sleep schedule that reduces sleep duration is thought to produce the increasing daytime sleepiness of adolescents. We tested the hypothesis that adolescent daytime sleepiness also results from adolescent brain maturational processes indexed by declining delta electroencephalographic (EEG) activity. DESIGN: Data are from the first 3 years of a semilongitudinal study of EEG changes in adolescence. All-night EEG was recorded semiannually. SETTING: EEG was recorded with ambulatory recorders in the subjects' homes. PARTICIPANTS: Thirty-one subjects were 9 years old (cohort C9), and 38 subjects were 12 years old (cohort C12) at the start of the study. MEASUREMENTS: EEG power density (power/minute) was calculated for the first 5 hours of non-rapid eye movement sleep. Subjects rated sleepiness on a modified Epworth Sleepiness Scale. Habitual sleep schedules were assessed with self-reports and actigraphy. RESULTS: In C9 subjects, sleepiness increased slightly and was related only to age. In C12 subjects, the increase in subjective sleepiness was related to changes in age, bedtime, time in bed, and a wide frequency range of EEG power density. Sleepiness was not related to rise time, non-rapid eye movement sleep duration, rapid eye movement sleep duration, or total sleep time. With sleep schedule measures statistically controlled, the increase in sleepiness in the C12 group was strongly related to declining delta power density and, unexpectedly, even more strongly related to declining theta power density. CONCLUSIONS: The data support our hypothesis that, independent of sleep schedule changes, increasing adolescent daytime sleepiness is related to brain maturational changes indexed by declining EEG power. Our working hypothesis is that the declines in delta and theta power are correlates of an adolescent synaptic pruning that reduces waking arousal levels.     

National Trends in Smoking Behaviors Among Mexican,Puerto Rican,and Cuban Men and Women in the United States

Objectives. We examined trends in smoking behaviors across 2 periods among Mexicans, Puerto Ricans, and Cubans in the United States.Methods. We analyzed data from the 1992–2007 Tobacco Use Supplements to the Current Population Survey. We constructed 2 data sets (1990s vs 2000s) to compare smoking behaviors between the 2 periods.Results. Significant decreases in ever, current, and heavy smoking were accompanied by increases in light and intermittent smoking across periods for all Latino groups, although current smoking rates among Puerto Rican women did not decline. Adjusted logistic regression models revealed that in the 2000s, younger Mexicans and those interviewed in English were more likely to be light and intermittent smokers. Mexican and Cuban light and intermittent smokers were less likely to be advised by healthcare professionals to quit smoking. Mexicans and Puerto Ricans who were unemployed and Mexicans who worked outdoors were more likely to be heavy smokers.Conclusions. Increases in light and intermittent smoking among Mexican, Puerto Rican, and Cuban Americans suggest that targeted efforts to further reduce smoking among Latinos may benefit by focusing on such smokers.Since 2000, Latinos have experienced the largest population growth of all US racial/ethnic groups, making Latinos the largest ethnic minority group in the country at 16.3% of the population.1 Mexicans, Puerto Ricans, and Cubans are the 3 largest Latino national and family background groups in the United States.1 The leading causes of death among Latinos are coronary heart disease and cancer, both of which are strongly associated with tobacco use.2,3 Although differences in smoking rates by Latino national origin groups have been found,4–6 very little research has examined trends in smoking behaviors for various Latino national origin groups by gender in the United States.The aggregation of smoking rates for various Latino national origin groups masks important variations within the population group.4 For example, smoking prevalence rates as determined by national data from 2008 are highest among Cubans (21.5%), followed by Mexicans (20.1%), and Puerto Ricans (18.6%).3 Puerto Ricans and Cubans are also more likely to be current smokers than are Mexicans.7 Furthermore, although research grounded on a nationally representative sample found that Latinos were approximately 4.5 times more likely to be light smokers than were non-Hispanic Whites,8 that study provided only aggregated rates for all Latinos and did not differentiate between national origin groups. Gender differences have also been reported among disaggregated Latino groups. A higher prevalence of smoking has been reported among Mexican (25.0%), Puerto Rican (27.6%), and Cuban (24.7%) men than among Mexican (10.4%), Puerto Rican (24.2%), and Cuban (12.4%) women.7 The lower rates of smoking among women have been consistent in surveys of Latinos.5,7,9 Results from these studies, although informative, have generally been determined by aggregated Latino data or data from a single survey time point. Although such data are valuable and can demonstrate existing gender differences, national-level trends from Latino nationality groups in the United States add valuable information that have not been previously reported.Previous research has also identified social and environmental factors associated with Latinos’ smoking behaviors. Acculturation to mainstream US culture plays a significant role in one’s health behaviors,10 and as Latinos acculturate, their smoking behaviors become similar to those of non-Hispanic Whites.7 Existing research has also revealed that Latinos are less likely to quit smoking,11 receive tobacco screening, and be advised to quit by a physician than are non-Hispanic Whites.12–15 A health professionals’ advice to quit smoking has been found to increase the likelihood that a smoker will successfully quit.16,17 Lastly, workplace smoking policies have also influenced smoking prevalence and intensity.18–20 Work environments adopting a smoke-free policy saw a 14% decrease in individuals’ smoking.21 When examining national-level smoking behaviors among Latinos, it is important to account for social and environmental factors such as acculturation, physician advice to quit smoking, and work environment smoking policies, as they may influence smoking behaviors.Existing research on smoking behaviors among Latino national origin groups has been predicated on data from specific regions of the United States.4,22–25 Although regional data are important for the development of community-level interventions,4 national-level data provide an overview of the country’s progress in tobacco control as well as remaining and emerging challenges for Latinos nationwide. We compared smoking behaviors across 2 periods, about a decade apart, among Mexicans, Puerto Ricans, and Cubans. Our goals in these analyses were (1) to compare Latino national origin groups across 2 periods to examine factors affecting changes in smoking behavior within and between groups, and (2) to evaluate demographic factors that influence current smoking behaviors within Latino national origin groups in the most recent period available. Examining long-term national trends in Latino smoking behaviors may prove vital to policymakers, public health officials, community workers, and interventionists as they address tobacco-related issues.     

The average cumulative risks of breast and ovarian cancer for carriers of mutations in BRCA1 and BRCA2 attending genetic counseling units in Spain.

PURPOSE: It is not clear that the published estimates of the breast and ovarian cancer penetrances of mutations in BRCA1 and BRCA2 can be used in genetic counseling in countries such as Spain, where the incidence of breast cancer in the general population is considerably lower, the prevalence of BRCA2 mutations seems to be higher, and a distinct spectrum of recurrent mutations exists for both genes. We aimed to estimate these penetrances for women attending genetic counseling units in Spain. EXPERIMENTAL DESIGN: We collected phenotype and genotype data on 155 BRCA1 and 164 BRCA2 mutation carrier families from 12 centers across the country. Average age-specific cumulative risks of breast cancer and ovarian cancer were estimated using a modified segregation analysis method. RESULTS: The estimated average cumulative risk of breast cancer to age 70 years was estimated to be 52% [95% confidence interval (95% CI), 26-69%] for BRCA1 mutation carriers and 47% (95% CI, 29-60%) for BRCA2 mutation carriers. The corresponding estimates for ovarian cancer were 22% (95% CI, 0-40%) and 18% (95% CI, 0-35%), respectively. There was some evidence (two-sided P = 0.09) that 330A>G (R71G) in BRCA1 may have lower breast cancer penetrance. CONCLUSIONS: These results are consistent with those from a recent meta-analysis of practically all previous penetrance studies, suggesting that women with BRCA1 and BRCA2 mutations attending genetic counseling services in Spain have similar risks of breast and ovarian cancer to those published for other Caucasian populations. Carriers should be fully informed of their mutation- and age-specific risks to make appropriate decisions regarding prophylactic interventions such as oophorectomy.     

Increased presence of white matter hyperintensities in adolescent patients with bipolar disorder

Several reports have noted an increase in white matter hyperintensities (WMH) on MRI scans of adult patients with bipolar disorder. We investigated whether this increase was also evident in a group of adolescent patients with bipolar disorder. The sample consisted of 15 bipolar patients, 19 patients with schizophrenia and 16 healthy comparison subjects. All subjects were adolescents. WMH were blindly rated on T2-weighted and PD-weighted MRI scans using our own scale with documented inter-rater reliability. WMH were present in 10 of 15 bipolar patients (67%), seven of 19 patients with schizophrenia (37%) and five of 16 comparison subjects (31%). The bipolar adolescent group had a statistically significant increased presence of WMH compared both with healthy comparison subjects and the schizophrenic group. The association between WMH and bipolar disorder appears to extend to the adolescent years.