Introduction: A high prevalence of modifiable risk factors exists among adolescents that may lead to increased levels of morbidity and mortality in adulthood. This study sought to determine whether higher levels of physical activity (PA) and/or having a healthy body weight in adolescence influences future health risk behaviors (HRB) in young adulthood. Methods: Complete data were gathered for 536 participants from a prospective study and a follow-up survey conducted 10 years apart. At both time points, the questionnaires included information about HRB, PA, and health status. Results: Males who engaged in HRB during adolescence were more likely to continue these same risk behaviors during adulthood. Using multivariate models, only HRB in adolescence predicted HRB in adulthood for drinking, binge drinking and smoking among males, and for binge drinking and smoking among females. Conclusions: It appears that for males, once a health-risk behavior is initiated, it will likely continue into young adulthood, regardless of the presence of other healthy behaviors such as the proper maintenance of body weight and higher levels of PA. Similarly for females, binge drinking and smoking in adolescence is predictive of the same behavior in adulthood.
According to the CDC, modifiable risk factors such as smoking, alcohol consumption, physical inactivity and poor diet are leading causes of morbidity and mortality in the United States [
The risk taking behaviors of interest in the present investigation focus on alcohol use and smoking. As a student progresses from middle school to high school, the likelihood of drinking alcohol, binge drinking and/or smoking increases, while the percentage of those maintaining an appropriate body weight and adequate physical activity level decreases [4,5]. Reports from the Youth Risk Behavior Surveillance System (YRBSS) and Behavioral Risk Factor Surveillance System (BRFSS) indicate that the percentage of adolescents who report consuming at least one drink of alcohol during the previous month increases dramatically from 7% of 12 - 14 years old to 27.5% of 15 - 17 years old [4,5]. This percentage continues to rise in the 18 - 20 years old category with values approximating drinking percentages during adulthood (51.3% and 54.3%, respectively). Similarly, binge drinking, defined as consuming five or more alcoholic drinks on at least one occasion in the past 30 days, also appears to peak between the ages of 18 - 20 years with 36.3% reporting the behavior. The second highest percent of binge drinkers are the 15 - 17 years old (17.8%), followed by adults (15.7%) and then those aged 12 - 14 years (3.3%) [4,5]. When examining this trend by gender, underage males were more likely than underage females to be current alcohol users (29.4% vs 27.8%, respectively) and binge drinkers (21.6% males, 16.5% females). Smoking has also been shown to increase throughout the high school years. According to the 2009 YRBSS, smoking prevalence increased from 13.5% in ninth grade to 18.3% in tenth, 22.3% in eleventh grade and peaked at 25.2% in twelfth grade [
In regard to health status, physical activity tended to decrease during the same time frame of ninth to twelfth grade. The percentage of students not participating in 60 minutes of physical activity on any of the seven days prior to the survey, increased from 21.8% in 9th grade, 22.6% in tenth, 22.9% in eleventh to 25.6% in twelfth [
When examining whether risk-taking behaviors during adolescence impact young adulthood behaviors, both alcohol use [6-8] and cigarette smoking [
Study subjects for this investigation come from the Epidemiology of Physical Activity from Adolescence to Adulthood study, a 20 year longitudinal cohort that has been followed from adolescence to adulthood and has been assessed during three separate cycles (phases). The original subjects, aged 12 - 16 years [n = 1245 adolescents (89% of the total student population)] were recruited in 1989 when they were enrolled in junior high school at a single school district in Pittsburgh, PA and followed for a period of four years (Phase I). The cohort consisted of similar numbers of male (n = 641) and female (n = 604) adolescents; and the racial composition was 73% white, 24% African American, and 3% Hispanic or Asian [15-17]. In 1999, subjects were re-contacted (aged 22 - 25 years of age) to participate in a follow-up study to examine changes in physical activity from adolescence to young adulthood (Phase II). A total of 827 (66%) completed an interviewer-administered, follow-up questionnaire which included information about health behaviors (i.e., smoking, drug and alcohol use, sedentary behavior), physical activity. Each phase of the current study was approved by the University of Pittsburgh Institutional Review Board and written informed consent was obtained from all participants and/or their parents prior to participation in any part of the study.
Physical activity (PA) was assessed using the Modifiable Activity Questionnaire for Adolescents (MAQ-A) [
During the 1999 follow-up (Phase II), trained interviewers administered a past year Modifiable Activity Questionnaire (MAQ) [20,21]. The MAQ, an interviewer-administered questionnaire for adults, assesses both leisure and occupational activities similar to the MAQ-A completed in the AIC study. The 1999 version asked participants to indicate activities that they had participated in at least ten times over the past year. For each activity, the months of participation was indicated as well as the average days per week and average minutes per day of participation. To assess occupational (non-leisure) activities, participants were also asked to list all jobs held for over one month during the past year and answered questions related to transporttation to and from work, days per week and hours per day of work, time spent sitting, and intensity of non-sitting work related activities.
Health risk behaviors were assessed during years 1, 2, and 4 of Phase I using the Center for Disease Control and Prevention’s Youth Risk Behavior Survey [
During the Phase I, height (cm) and weight (kg) were measured annually with a standard balance scale and used to calculate body mass index (BMI; kg/m2). Shoes were removed prior to all measurements of height and weight. During the Phase II follow-up, BMI was calculated from self-reported height and weight on the questionnaire.
Only participants that had BMI and complete physical activity data at all time-points during Phase I and Phase II (years 1990-1993 and 1999/2000) were included in the analyses. All continuous data were assessed for normality. Normally distributed data are reported as mean (SD), non-normal variables as median (Interquartile range). Categorical data are presented as percentages. Descriptive statistics were calculated for the total cohort and sex-specific grouping. Comparisons between sexes of continuous variables were assessed using a twosample t-test or the Wilcoxon test. Categorical variables were assessed using the Pearson chi-square test. Evaluation of the change in HRB from adolescence to adulthood was performed using a Mc-Nemar’s test.
A series of gender-specific logistic regression models were utilized to evaluate the independent impact of PA, BMI, and adolescent health risk behavior (HRB) on adult HRB. Independent variables included in the regression analyses were treated categorically. Gender-specific physical activity levels were divided into “high” and “low” groups using a median split. BMI was categorized into “normal” (<25.0 kg/m2) and “overweight/obese” (≥25.0 kg/m2) according to NHLBI BMI guidelines [
A total of 1245 individuals participated in Phase I, of which 828 participants (67% of original Phase Icohort) completed a follow-up questionnaire, in adulthood, as part of the Phase II. Complete data were available for 536 participants (
Descriptive statistics for the 536 subjects are provided from Phase I (