Kirby L. Jackson

Frequency of obsessive-compulsive disorder in a community sample of young adolescents.

OBJECTIVE To investigate the frequency and phenomenology of obsessive-compulsive disorder (OCD) and subclinical OCD in young adolescents. METHOD A two-stage epidemiological study originally designed to investigate adolescent depression was conducted between 1986 and 1988 in the southeastern United States. In the first stage, a self-report depressive symptom questionnaire was administered to a community sample of 3,283 adolescents. In the diagnostic stage, the Schedule for Affective Disorders and Schizophrenia for School-Age Children and the Childrens Global Assessment Scale were administered to 488 mother-child pairs. RESULTS The prevalences of OCD and subclinical OCD were found to be 3% and 19%, respectively. Prevalences were similar in males and females. Females reported more symptoms of compulsions although males reported more obsessions. About 55% of adolescents with OCD reported both obsessions and compulsions. The most common compulsions were arranging (56%), counting (41%), collecting (38%), and washing (17%). Major depressive disorder (45%), separation anxiety (34%), dysthymia (29%), suicidal ideation (15%), and phobia (8%) were the diagnoses most frequently comorbid with OCD. CONCLUSIONS Findings suggest that OCD is not infrequent among adolescents and that the characteristic comorbidity and symptomatology of OCD may facilitate earlier identification and treatment by clinicians.

The CES-D as a Screen for Depression and Other Psychiatric Disorders in Adolescents

The performance of the Center for Epidemiologic Studies Depression Scale (CES-D) as a screen for depression was explored in a two-stage epidemiological study of adolescents. The study consisted of a CES-D screening stage completed by a school sample of 2,465 young adolescents and a structured psychiatric interview stage completed by 332 mother-adolescent pairs. Adolescents with interview validated depression had elevated screening scores (mean = 31.10, SD = 11.30) compared with individuals with no disorder (mean = 21.01, SD = 11.77). Using receiver operating characteristic curves, a cut point of 12 for males produced the best overall screening characteristics (sensitivity = 0.85, specificity = 0.49), while for females, a cut point of 22 was optimal (sensitivity = 0.83, specificity = 0.77).

Evaluation of the Kaiser Physical Activity Survey in women

PURPOSE The Kaiser Physical Activity Survey (KPAS) was evaluated for test-retest reliability and comparison with direct and indirect measures of physical activity (PA) in 50 women (ages 20-60 yr) with a broad range of physical activity (PA) habits. METHODS The KPAS, an adaptation of the Baecke usual physical activity survey, was designed specifically to assess activity in women. It provides four summary activity indexes: housework/caregiving, active living habits, sports, and occupation. Summary indexes were compared against direct (Caltrac accelerometer and PA records) and indirect (cardiorespiratory fitness (VO2 peak) and percent body fat) criterion measures of PA. Participants kept detailed PA records for two, 7-d periods, separated by 1 month. Caltrac accelerometers were worn concurrently with the PA records. RESULTS Intraclass correlations for 1-month test-retest reliability were high for all KPAS indexes (r = 0.79 to 0.91, P < 0.01). Age-adjusted Spearman rho correlations between the KPAS sports/exercise and active living habits indexes were of moderate magnitude for VO2 peak (r = 0.34 to 0.76, P < 0.01) and percent body fat (r = -.30 to -0.59, P < 0.05). KPAS caregiving and occupation indexes were related to Caltrac kcal x d(-1) (r = 0.30 to 0.44, P < 0.05). Correlations between similar activities from the KPAS and PA records ranged from r = 0.03 to 0.64. Daily, habitual activities from the KPAS and PA records had the highest correlations (r > 0.28). Correlations among infrequent activities were lower (r < 0.05). CONCLUSION The KPAS demonstrated good reliability and was reasonably accurate in detecting regular housework/caregiving, occupation, sports/exercise, and active leisure activities among women with a broad range of physical activity habits.

Prevalence of PTSD in a community sample of older adolescents

OBJECTIVE To examine prevalence and correlates of trauma and posttraumatic stress disorder (PTSD) symptoms and diagnosis in older adolescents aged 16 through 22 years. METHOD The second cycle of a longitudinal epidemiological study in the Southeast included a semistructured interview assessing PTSD symptomatology administered to 490 adolescents. RESULTS Approximately 3% of female subjects and 1% of male subjects satisfied the DSM-IV criteria for PTSD. Females reported more traumatic events than males, and black subjects reported more events than white subjects. Being female (odds ratio = 12.32), experiencing rape or child sexual abuse (odds ratio = 49.37), and witnessing an accident or medical emergency (odds ratio = 85.02) were associated with increased risk of PTSD. CONCLUSIONS While relatively few adolescents satisfy the criteria for PTSD, most subjects who experienced a traumatic event reported some PTSD symptoms. Specific types of traumatic events were associated with occurrence of PTSD.

Exercise and the incidence of upper respiratory tract infections

We examined illness patterns in a cohort of 530 male and female runners who completed a monthly log for 12 months. The average number of upper respiratory tract infections (URTIs) per person per year for the cohort was 1.2. An upper respiratory tract infection was indicated by the report of any of the following symptoms; runny nose, sore throat, or cough. Using a multiple logistic regression model, the following factors were found to be associated with having one or more URTIs in the follow-up period: living alone (odds ratio = 2.27, 95% CI = 1.01, 5.09), running mileage (486-865 miles, odds ratio = 2.00, 95% CI = 1.01, 2.78; 866-1388 miles, odds ratio = 3.50, 95% CI = 1.52, 4.44; greater than 1388 miles, odds ratio = 2.96, 95% CI = 1.30, 3.68), body mass index greater than the 75th percentile (odds ratio = 0.58, 95% CI = 0.35, 0.94), and male gender (odds ratio = 0.14, 95% CI = 0.03, 0.68). A significant interaction was found to exist between gender and alcohol use, with the association between alcohol use and upper respiratory tract infections being positive in males and negative in females. These results suggest that running dosage (mileage) is a significant risk factor for upper respiratory tract infections in this group of exercisers.

Incidence and Predictors of Suicidal Behaviors in a Longitudinal Sample of Young Adolescents

OBJECTIVE This analysis examines 1-year transition probabilities and baseline predictors for suicidal behaviors in young adolescents. METHOD Adolescents from a two-stage, community-based longitudinal study were classified into suicidal behavior categories (attempt, plan, ideation, and none) for baseline and follow-up years. Transition probabilities for movement among categories were calculated, and polytomous logistic regression analysis was used to examine predictors of suicidal behaviors. RESULTS Among those with no suicidal behaviors at baseline, 1-year incidence rates were 1.3% for attempts and 1.7% each for plans and ideation. Increasing family cohesion was protective for suicide attempts (odds ratio [OR] = 0.9). Female subjects were more likely than males to report plans (OR = 8.9) and ideation (OR = 4.1). Increasing impulsivity (OR = 2.3), prior suicidal behavior (OR = 10.6), and undesirable life events (OR = 1.1) were significant predictors of plans. CONCLUSIONS While there are a number of predictors of suicidal behaviors, the false-positive rate is high. Focusing on proximal risk factors, particularly stressors in adolescent development, may overlook the fundamental role of underlying mental disorder and familial factors--both biological and environmental. Suicide and suicidal behaviors are the result of a constellation of adverse factors requiring a range of interventions for prevention.

Incidence of Major Depressive Disorder and Dysthymia in Young Adolescents

OBJECTIVE An epidemiological study conducted between 1987 and 1989 in a single school district in the southeastern United States investigated the incidence, transition probabilities, and risk factors for major depressive disorder (MDD) and dysthymia in adolescents aged 11 to 16 years. METHOD Diagnoses were based on the Schedule for Affective Disorders and Schizophrenia for School-Age Children, which was administered to 247 mother-adolescent pairs at 12-month intervals. RESULTS One-year MDD and dysthymia incidences were 3.3% (n = 11) and 3.4% (n = 9), respectively. Transition probabilities demonstrated movement from disorder to no disorder over time. Family cohesion (odds ratio = 0.95) was the only significant predictor of incident MDD. No factors were significant for dysthymia. While baseline MDD was a significant risk factor for depression at follow-up, 80% of subjects with baseline MDD did not meet the criteria for diagnosis at follow-up. CONCLUSION Findings suggest perceived family support or cohesion may be more important to adolescent mental health than family structure.

Exaggerated blood pressure response to dynamic exercise and risk of future hypertension

This study examined the association between an exaggerated blood pressure response to treadmill exercise and the risk of developing hypertension. Subjects were healthy normotensive men (n = 5386) who had a baseline graded maximal exercise test between 1971 and 1982, and completed a mailed follow-up questionnaire. At follow-up in 1986, cases (n = 151) reported physician diagnosed hypertension and controls (n = 201) reported normotension. Those who had developed hypertension at follow-up were more likely to have had an exaggerated blood pressure response to exercise (OR = 2.4, 1.4-4.3). In multiple logistic regression analysis an exaggerated response was significantly associated (OR = 3.0, 1.5-6.1) with future hypertension after controlling for sitting systolic and diastolic blood pressure, weight change from age 21 to follow-up, entry age, family history of hypertension, body mass index, treadmill time, alcohol consumption, and years of follow-up. These results suggest that an exaggerated blood pressure response to exercise is independently associated with increased risk of future hypertension, and therefore, may be an important factor in determining hypertension risk.

Patterns of non-response to a mail survey

This paper describes a basic investigation of possible non-response bias in a mail survey. We compare characteristics of responders and non-responders to a mail survey of health outcomes among participants of a longitudinal study of physical activity, physical fitness, and health. Results indicate that, at the first clinic visit, the responders were essentially the same as the non-responders on personal health history and laboratory measurements, while reporting significantly more family history of specific chronic diseases (cardiovascular disease, hypertension, stroke). The male responders were younger and reported more positive health behaviors as well as better weight and treadmill times at the first clinic visit. These results suggest that both response groups were equally healthy at entry, and that individuals who had family members with certain chronic conditions and who had positive health behaviors were more likely to respond (participate) in this health-related survey. Differences of this type could affect interpretation of future analyses. This work illustrates the importance of incorporating methods to examine non-response into any epidemiologic study.

Black—White differences in body size perceptions and weight management practices among adolescent females

OBJECTIVE This study compares body size perceptions and weight management practices of black and white adolescent females. DESIGN Subjects were selected through a statewide, three-stage sampling procedure designed to provide a sample statistically representative of high school students in South Carolina. SUBJECTS Participants included black (n = 1824) and white (n = 2256) females, 14-18 years of age, enrolled in South Carolina public high schools. METHODS Respondents were asked to assess their perceived body size as overweight, underweight, or about right. Self-reported weight management practices included dieting (reducing caloric intake), exercise, and other methods (including diet pills and vomiting). Chisquare analysis was used to assess the differences in body size perception and weight management behaviors. Polychotomous logistic regression was performed to examine association while controlling for socioeconomic status. RESULTS Forty-one percent of the white adolescents and 29% of the black adolescents perceive themselves as overweight (p < 0.005). In the week prior to the survey, 28% of the white adolescents and 13% of the black adolescents reported dieting 34% of the while versus 23% of the black adolescents reported exercising to lose weight; and 45% of the white and 16% of the black students reported both dieting and exercising. Polychotomous logistic regression analysis showed that white adolescent girls were almost twice as likely to perceive themselves as overweight as black adolescent girls. The white students had 6.04 [95% confidence interval (CI), 1.77, 20.67] times the odds of using pills and vomiting and 3.76 (95% CI, 2.99, 4.72) times the odds of engaging in dieting and exercising as methods of weight management compared to the black students. CONCLUSIONS These findings suggest that white adolescents are more likely to perceive themselves as overweight than black adolescents and are more likely to engage in unhealthy weight management practices than black adolescents.