Obesity and weight gain in relation to depression: findings from the Stirling County Study.

OBJECTIVE: This study concerns the question of whether obese subjects in a community sample experience depression in a different way from the nonobese, especially whether they overeat to the point of gaining weight during periods of depression. DESIGN: A representative sample of adults was interviewed regarding depression and obesity. SUBJECTS: The sample consisted of 1396 subjects whose interviews were studied regarding relationships between obesity and depression and among whom 114 had experienced a major depressive episode at some point in their lives and provided information about the symptoms experienced during the worst or only episode of major depression. MEASUREMENTS: The Diagnostic Interview Schedule (DIS) was used to identify major depressive episodes. Information was also derived from the section on Depression and Anxiety (DPAX) of the Stirling Study Schedule. Obesity was calculated as a body mass index >30. Logistic regressions were employed to assess relationships, controlling for age and gender, by means of odds ratios and 95% confidence intervals. RESULTS: In the sample as a whole, obesity was not related to depression although it was associated with the symptom of hopelessness. Among those who had ever experienced a major depressive episode, obese persons were 5 times more likely than the nonobese to overeat leading to weight gain during a period of depression (P<0.002). These obese subjects, compared to the nonobese, also experienced longer episodes of depression, a larger number of episodes, and were more preoccupied with death during such episodes. CONCLUSIONS: Depression among obese subjects in a community sample tends to be more severe than among the nonobese. Gaining weight while depressed is an important marker of that severity. Further research is needed to understand and possibly prevent the associations, sequences and outcomes among depression, obesity, weight gain and other adversities.

Anxiety and depression: a 40-year perspective on relationships regarding prevalence, distribution, and comorbidity.

OBJECTIVE: Building on a report about the prevalence of depression over time, this paper examines historical trends regarding anxiety in terms of its prevalence, its distribution by age and gender, and its comorbidity with depression. Methods for conducting such time trend analysis are reviewed. METHOD: Representative samples of adults were selected and interviewed in 1952, 1970, and 1992. Logistic regressions were used for statistical analysis. RESULTS: Although twice as common as depression, the prevalence of anxiety was equally stable. Anxiety was consistently and significantly more characteristic of women than men. A re-distribution of rates in 1992 indicated that depression but not anxiety had significantly increased among younger women (P = 0.03). Throughout the study, approximately half of the cases of anxiety also suffered depression. CONCLUSION: The relationships between anxiety and depression remained similar over time with the exception that depression came to resemble anxiety as a disorder to which women were significantly more vulnerable than men. Social and historical factors should be investigated to assess their relevance to this change.

Multiple informants: mortality associated with psychiatric disorders in the Stirling County Study.

This paper applies new statistical procedures for analyzing multiple-source information about the relation of psychiatric diagnoses to mortality. The data come from the Stirling County Study, a longitudinal community investigation of adults, that collected multiple-source reports (self-report and physician-report) about psychiatric disorders. These reports are used as predictors of mortality risk over a 16-year follow-up period (1952-1968). Despite extensive efforts, one or both of these reports were sometimes missing. Missingness of self-report was related to demographic characteristics as well as to physician-reports of psychiatric diagnosis. The statistical procedures used here draw together into a single frame of reference both informant reports for the initial Stirling survey and relate these to mortality risk using weighted generalized estimating equation regression models for time to event data. This unified method has two advantages over traditional approaches: 1) the relative predictiveness of each informant can be assessed and 2) all subjects contribute to the analysis. The methods are applicable to other areas of epidemiology where multiple informant reports are used. The results for self-reports and physician-reports of disorders were comparable: Psychiatric diagnosis was associated with higher mortality, particularly among younger subjects.

Household television access: associations with screen time, reading, and homework among youth.

OBJECTIVE: We examined how household factors that mediate television access are associated with screen time (television, videos, movies, and computer and video games), reading, and homework. METHODS: We conducted a self-report survey among 1197 sixth and seventh graders in 10 middle schools in 4 Boston-area communities in 1995. To assess independent associations, SUDAAN linear regressions were calculated to control for respondent characteristics and household access and to account for clustered sampling in the school-based design. RESULTS: Total viewing (television, videos, movies, and computer and video games) averaged 3.35 plus minus 2.2 hours per day. In multivariate regressions, independent direct associations with total viewing were observed for the following categories: youth has a television in the bedroom: 0.64 hours per day (P <.001), never/seldom has family dinners: 0.55 hours (P <.01); no parental limits on television time: 0.48 hours (P <.01); and each additional television outside the youth's bedroom, 0.12 hours (P <.05). Similar results held when television/video/movie use was examined separately from computer/video game use. Youth reported an average of 1.6 plus minus 1.1 hours of reading and homework per day. Parental limits on television time were associated with 0.21 hours more reading per day (P <.01), whereas a television in the bedroom was associated with 0.18 hours less (P <.01). CONCLUSIONS: Reducing intrahousehold television access may enhance clinical, school, and community strategies to reduce youth television viewing and other screen time.

Incidence of depression in the Stirling County Study: historical and comparative perspectives.

BACKGROUND: The Stirling County Study provides a 40-year perspective on the epidemiology of psychiatric disorders in an adult population in Atlantic Canada. Across samples selected in 1952, 1970 and 1992 current prevalence of depression was stable. This paper concerns time trends in annual incidence as assessed through cohorts selected from the first two samples. METHODS: Consistent interview data were analysed by a computerized diagnostic algorithm. The cohorts consisted of subjects at risk for a first depression: Cohort-1 (N = 575) was followed 1952-1970; Cohort-2 (N = 639) was followed 1970-1992. Life-table methods were used to calculate incidence rates and proportional hazards procedures were used for statistical assessment. RESULTS: Average annual incidence of depression was 4.5 per 1000 for Cohort-1 and 3.7 for Cohort-2. Differences by gender, age and time were not statistically significant. The stability of incidence and the similarity of distribution by gender and age in these two cohorts corresponds to findings about the two early samples. In contrast, current prevalence in the recent sample was distributed differently and showed an increase among women under 45 years. CONCLUSIONS: The stability of the incidence of depression emphasizes the distinctive characteristics of current prevalence in the recent sample and suggests that the dominance of women in rates of depression may have occurred among those born after the Second World War. The results offer partial support for the interpretation of an increase in depression based on retrospective data in other recent studies but they indicate that the increase is specific to women.

A 40-year perspective on the prevalence of depression: the Stirling County Study.

BACKGROUND: According to epidemiologic studies that use recall of lifetime episodes, the prevalence of depression is increasing. This report from the Stirling County Study compares rates of current depression among representative samples of adults from a population in Atlantic Canada. METHODS: Sample sizes were 1003, 1201, and 1396 in 1952, 1970, and 1992, respectively. The depression component of the study's method, the DPAX (DP for depression and AX for anxiety), was employed. The original procedure (DPAX-1) was applied in all years. A revision (DPAX-2) was used in 1970 and 1992. The Diagnostic Interview Schedule (DIS) was also used in 1992. RESULTS: With the DPAX-1, the overall prevalence of current depression was steady at 5% over the 2 early samples but declined in 1992 because of vernacular changes referring to dysphoria. The DPAX-2 gave a stable overall prevalence of 5% in the 2 recent samples, but indicated that women and younger people were at greater risk in 1992 than in 1970. The DIS, like the DPAX-2, found a current 1992 rate of 5% for major depressive episodes combined with dysthymia. Recalled lifetime rates using the DIS showed the same profile interpreted in other studies as suggesting an increase in depression over time. CONCLUSIONS: Three samples over a 40-year period showed a stable current prevalence of depression using the DPAX methods that was comparable in 1992 with the current rates using the DIS. This casts doubt on the interpretation that depression is generally increasing. Within the overall steady rate observed in this study, historical change was a matter of redistribution by sex and age, with a higher rate among younger women being of recent origin.

A comparison of diagnostic interviews for depression in the Stirling County study: challenges for psychiatric epidemiology.

BACKGROUND: High prevalence rates in psychiatric epidemiologic studies raise questions about whether data-gathering procedures identify transient responses rather than clinical disorders. This issue is explored relevant to depression using data from the Stirling County Study. METHODS: The study's customary method, the DPAX (DP for depression and AX for anxiety) was compared with the Diagnostic Interview Schedule (DIS), both of which were administered to a sample of 1396 subjects selected in 1992. Reasons for discordance were analyzed, and demographic correlates of responses to questions about dysphoria were examined. These lay-administered interviews were then compared with clinician-administered interviews that used the Structured Clinical Interview for DSM-III-R (SCID) with 139 subjects. The kappa statistic and logistic regression were used for statistical assessment. RESULTS: For the level of agreement between the DPAX and the DIS for current and lifetime depression, kappa = 0.40 and kappa = 0.33, respectively. Subjects diagnosed only by the DPAX tended to have less education than those diagnosed only by the DIS. Some idioms for dysphoria seemed to work better than others. Using SCID interviews as a clinical standard, the DPAX had 15% sensitivity and 96% specificity and the DIS had 25% sensitivity and 98% specificity. CONCLUSIONS: Comprehension of an interview can be improved by using multiple questions for dysphoria and a simpler mode of inquiry. Clinician-administered interviews tend to corroborate disorders identified in lay-administered interviews but suggest that survey methods underestimate prevalence. Further research is needed to evaluate the validity of both types of interviews, but evidence from a 16-year follow-up evaluation indicates that depression diagnosed by the DPAX is a serious disorder in terms of morbidity and mortality.

Impact of a school-based interdisciplinary intervention on diet and physical activity among urban primary school children: eat well and keep moving.

OBJECTIVE: To evaluate the impact of a school-based interdisciplinary health behavior intervention on diet and physical activity among children in grades 4 and 5. DESIGN: A quasiexperimental field trial with 6 intervention and 8 matched control schools. Outcomes were assessed longitudinally using preintervention (fall 1995) and follow-up (spring 1997) student survey food frequency and activity measures and follow-up 24-hour recall measures of diet and activity. Change was also assessed using yearly repeated cross-sectional surveys of all grade 5 students from 1995 through 1997. PARTICIPANTS: Longitudinal data were collected from 479 students initially in grade 4 in Baltimore, Md, public schools; 91% were African American. Repeated 24-hour recall measures in 1997 were collected for a random subsample of 336 students. Cross-sectional survey data were collected from all grade 5 students in 1995,1996, and 1997 (n = 2103). INTERVENTION: The Eat Well and Keep Moving Program was taught by classroom teachers over 2 years in math, science, language arts, and social studies classes. Materials provided links to school food services and families and provided training and wellness programs for teachers and other staff members. Intervention materials focused on decreasing consumption of foods high in total and saturated fat and increasing fruit and vegetable intake, as well as reducing television viewing and increasing physical activity. MAIN OUTCOME MEASURES: Dietary intake and physical activity measured via repeated 24-hour recall were primary end points, with additional food frequency and activity measures. RESULTS: The 24-hour recall measures indicated that, after controlling for baseline covariates, the percentages of total energy from fat and saturated fat were reduced among students in intervention compared with control schools (-1.4%; 95% confidence interval [CI], -2.8 to -0.04; P = .04 and -0.60%; 95% CI, -1.2 to -0.01; P = .05). There was an increase in fruit and vegetable intake (0.36 servings/4184 kJ; 95% CI, 0.10-0.62; P=.01), in vitamin C intake (8.8 mg/4184 kJ; 95% CI, 2.0-16; P=.01), and in fiber consumption (0.7 g/4184 kJ; 95% CI, 0.0-1.4; P=.05). Television viewing was marginally reduced (-0.55 h/d; 95% CI, -1.04 to 0.04; P=.06). Analysis of longitudinal and repeated cross-sectional food frequency data indicated similar significant decreases in the percentages of total energy from fat and saturated fat. CONCLUSION: Evaluation of the Eat Well and Keep Moving Program indicates effectiveness in improving dietary intake of students and reducing television viewing.

Reducing obesity via a school-based interdisciplinary intervention among youth: Planet Health.

OBJECTIVE: To evaluate the impact of a school-based health behavior intervention known as Planet Health on obesity among boys and girls in grades 6 to 8. DESIGN: Randomized, controlled field trial with 5 intervention and 5 control schools. Outcomes were assessed using preintervention (fall 1995) and follow-up measures (spring 1997), including prevalence, incidence, and remission of obesity. PARTICIPANTS: A group of 1295 ethnically diverse grade 6 and 7 students from public schools in 4 Massachusetts communities. INTERVENTION: Students participated in a school-based interdisciplinary intervention over 2 school years. Planet Health sessions were included within existing curricula using classroom teachers in 4 major subjects and physical education. Sessions focused on decreasing television viewing, decreasing consumption of high-fat foods, increasing fruit and vegetable intake, and increasing moderate and vigorous physical activity. MAIN OUTCOME MEASURES: Obesity was defined as a composite indicator based on both a body mass index and a triceps skinfold value greater than or equal to age- and sex-specific 85th percentiles. Because schools were randomized, rather than students, the generalized estimating equation method was used to adjust for individual-level covariates under cluster randomization. RESULTS: The prevalence of obesity among girls in intervention schools was reduced compared with controls, controlling for baseline obesity (odds ratio, 0.47; 95% confidence interval, 0.24-0.93; P = .03), with no differences found among boys. There was greater remission of obesity among intervention girls vs. control girls (odds ratio, 2.16; 95% confidence interval, 1.07-4.35; P = .04). The intervention reduced television hours among both girls and boys, and increased fruit and vegetable consumption and resulted in a smaller increment in total energy intake among girls. Reductions in television viewing predicted obesity change and mediated the intervention effect. Among girls, each hour of reduction in television viewing predicted reduced obesity prevalence (odds ratio, 0.85; 95% confidence interval, 0.75-0.97; P = .02). CONCLUSION: Planet Health decreased obesity among female students, indicating a promising school-based approach to reducing obesity among youth.

Home uterine activity monitoring in the prevention of very low birth weight.

OBJECTIVES: Despite controversy regarding the efficacy of home uterine activity monitoring (HUAM), it is currently licensed for detection of preterm labor in women with previous preterm deliveries. In practice, however, it is being more widely utilized in an effort to prevent preterm delivery. This study seeks to determine which group of mothers delivering very low birth weight (VLBW) infants would have qualified for HUAM given three different sets of criteria and in which women it could have been used to help prolong gestation. METHODS: The authors reviewed the medical records of mothers of VLBW infants born in five U.S. locations (N = 1440), retrospectively applying three sets of eligibility criteria for HUAM use: (a) the current FDA licensing criterion for use of HUAM, a previous preterm birth; (b) indication for HUAM commonly cited in published reports; (c) a broad set of criteria based on the presence of any reproductive or medical conditions that might predispose to premature delivery. The authors then analyzed the conditions precipitating delivery for each group to determine whether delivery might have been prevented with HUAM and tocolytic therapy. RESULTS: Only 4.4% of the total group of women delivering VLBW infants would have been eligible for HUAM under the FDA criterion and might potentially have benefited from this technology. If extremely broad criteria had been applied to identify those eligible for monitoring, under which almost 80% of all women who delivered VLBW infants would have been monitored, only 20.3% of the total group would have been found eligible and would potentially have benefited. If such broad criteria were applied to all pregnant women, a sizable proportion of pregnancies would be monitored at great expense with small potential clinical benefit. CONCLUSIONS: Because VLBW births are usually precipitated by conditions that are unlikely to benefit from HUAM, this technology will have little impact on reducing VLBW and neonatal mortality rates. More comprehensive preventive strategies should be sought.

Television viewing as a cause of increasing obesity among children in the United States, 1986-1990.

BACKGROUND AND METHODS: The prevalence of obesity among children and adolescents has increased, and television viewing has been suggested as a cause. We examined the relation between hours of television viewed and the prevalence of overweight in 1990, and the incidence and remission of overweight from 1986 to 1990 in a nationally representative cohort of 746 youths aged 10 to 15 years in 1990 whose mothers were 25 to 32 years old. Overweight was defined as a body mass index higher than the 85th percentile for age and gender. RESULTS: We observed a strong dose-response relationship between the prevalence of overweight in 1990 and hours of television viewed. The odds of being overweight were 4.6 (95% confidence interval, 2.2 to 9.6) times greater for youth watching more than 5 hours of television per day compared with those watching 0 to 2 hours. When adjustments were made for previous overweight (in 1986), baseline maternal overweight, socioeconomic status, household structure, ethnicity, and maternal and child aptitude test scores, results were similar (odds ratio, 5.3; 95% confidence interval, 2.3 to 12.1). We also found significant relations between television viewing and increased incidence and decreased remission of overweight during this 4-year period, adjusted for baseline covariates. The adjusted odds of incidence were 8.3 (95% confidence interval, 2.6 to 26.5) times greater for youth watching more than 5 hours of television per day compared with those watching for 0 to 2 hours. Estimates of attributable risk indicate that more than 60% of overweight incidence in this population can be linked to excess television viewing time. CONCLUSION: Television viewing affects overweight among youth, and reductions in viewing time could help prevent this increasingly common chronic health condition.

Organ donor potential and performance: size and nature of the organ donor shortfall.

OBJECTIVES: To estimate the potential for solid organ donation; to identify modifiable reasons for nondonation. DESIGN: Retrospective medical records review. SETTING: Sixty-nine acute care hospitals in four geographic areas of the United States in 1990, and a stratified random sample of 89 hospitals in three of the same areas and 33 of the same hospitals in 1993. PATIENTS: PATIENTS < or = 70 yrs of age who were brain dead and medically suitable for donation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Standard forms were used to record patient demographic and hospital information. Reasons for nondonation were coded as "not identified," "family not asked," "consent denied," or "other." The main outcome measures were rate of donation and rates of nonidentification, not asking, and nonconsent. Organ donation occurred among 33% (299/916) of medically suitable cases identified in 1990 (95% confidence interval 30% to 36%). Ninety-four potential donors were not identified, 156 were not asked, 326 families denied consent, and 41 potential donors were categorized as "other," including patients who had suffered a cardiac arrest, and medical examiner prohibition of donation. In the 1993 study, organ donation occurred in an estimated 33% of suitable cases. In 1990, rates of donation were highest among patients <50 yrs of age, patients who died of traumatic causes, and non-Hispanic white patients. Logistic regression showed lower odds of donation for African American patients (odds ratio 0.38, 95% confidence interval 0.23 to 0.63) independent of potentially confounding hospital and patient variables (p=.0001). Donation rates did not vary by hospital size or type. CONCLUSIONS: Despite legal and policy initiatives, only one third of potential donors became donors in 1990, with similar results in 1993. Extrapolating the 1990 findings to the United States suggests a pool of 13,700 medically suitable donors per year. Prospective identification and requesting donation in all suitable potential donor cases could lead to 1,800 additional donors per year.

Social and economic consequences of overweight in adolescence and young adulthood.

BACKGROUND AND METHODS: Overweight in adolescents may have deleterious effects on their subsequent self-esteem, social and economic characteristics, and physical health. We studied the relation between overweight and subsequent educational attainment, marital status, household income, and self-esteem in a nationally representative sample of 10,039 randomly selected young people who were 16 to 24 years old in 1981. Follow-up data were obtained in 1988 for 65 to 79 percent of the original cohort, depending on the variable studied. The characteristics of the subjects who had been overweight in 1981 were compared with those for young people with asthma, musculoskeletal abnormalities, and other chronic health conditions. Overweight was defined as a body-mass index above the 95th percentile for age and sex. RESULTS: In 1981, 370 of the subjects were overweight. Seven years later, women who had been overweight had completed fewer years of school (0.3 year less; 95 percent confidence interval, 0.1 to 0.6; P = 0.009), were less likely to be married (20 percent less likely; 95 percent confidence interval, 13 to 27 percent; P < 0.001), had lower household incomes ($6,710 less per year; 95 percent confidence interval, $3,942 to $9,478; P < 0.001), and had higher rates of household poverty (10 percent higher; 95 percent confidence interval, 4 to 16 percent; P < 0.001) than the women who had not been overweight, independent of their base-line socioeconomic status and aptitude-test scores. Men who had been overweight were less likely to be married (11 percent less likely; 95 percent confidence interval, 3 to 18 percent; P = 0.005). In contrast, people with the other chronic conditions we studied did not differ in these ways from the nonoverweight subjects. We found no evidence of an effect of overweight on self-esteem. CONCLUSIONS: Overweight during adolescence has important social and economic consequences, which are greater than those of many other chronic physical conditions. Discrimination against overweight persons may account for these results.

Recent trends in the prevalence and severity of childhood asthma.

OBJECTIVE: To examine changes in the prevalence and distribution of childhood asthma and its relationship with various measures of children's health and functioning between 1981 and 1988. It was hypothesized that there would be an increase in the prevalence of asthma, especially among black children, and that available measures would suggest a deterioration in the health and functioning of children with asthma over this period. DESIGN: Analyses of data from the Child Health Supplements to the National Health Interview Survey. SETTING AND SAMPLE: Nationally representative random sample of 15,224 children aged 0 to 17 years in 1981 and 17,110 in 1988. MAIN OUTCOME MEASURES: Changes in (1) the prevalence and distribution of asthma, and (2) among children with asthma, the percentage of children hospitalized, days spent in bed, school days lost in the year prior to survey, and parent ratings and reports of children's overall health status and behavior problems. RESULTS: The estimated prevalence of childhood asthma increased from 3.1% in 1981 to 4.3% in 1988 (P < .0001), with similar increases for children, adolescents, and both sexes. Increases occurred among white children (2.7% to 4.1%; P < .0001) but not black children (5.3% vs 5.1%; not significant). Among those with asthma in 1988 compared with 1981, there was better overall health status (11% vs 24% fair/poor; P < .0001) and fewer with 30 or more days spent in bed in the last year (3.9% vs 7.2%; P < .04). We also observed trends toward a lower rate of hospitalization in the last year (10% vs 14%; P = .07), fewer school days missed (2% vs 6% with > 30 days; P = .08), and a lower rate of extreme behavior problem scores (13% vs 18%; P = .09) in 1988 compared with 1981. Reductions were similar among both black and white children. CONCLUSIONS: These results indicate that the estimated prevalence of asthma among children in the United States increased by almost 40%, and that although the increase occurred exclusively among white children, the prevalence of asthma still remains higher in black children than in white children. There was no support for increasing asthma severity and functional impact among either black or white children with asthma in 1988 compared with 1981. These findings provide no evidence to support the beliefs that asthma prevalence is increasing largely among black children or that the severity of asthma among most children in the United States is increasing.

Clinical determinants of the racial disparity in very low birth weight.

BACKGROUND: Although the risk of very low birth weight (less than 1500 g) is more than twice as high among blacks as among whites in the United States, the clinical conditions associated with this disparity remain poorly explored. METHODS AND RESULTS: We reviewed the medical records of over 98 percent of all infants weighing 500 to 1499 g who were born in Boston during the period 1980 through 1985 (687 infants), in St. Louis in 1985 and 1986 (397 infants), and in two health districts in Mississippi in 1984 and 1985 (215 infants). The medical records of the infants' mothers were also reviewed. These data were linked to birth-certificate files. During the study periods, there were 49,196 live births in Boston, 16,232 in St. Louis, and 16,332 in the Mississippi districts. The relative risk of very low birth weight among black infants as compared with white infants ranged from 2.3 to 3.2 in the three areas. The higher proportion of black infants with very low birth weights was related to an elevated risk in their mothers of major conditions associated with very low birth weight, primarily chorioamnionitis or premature rupture of the amniotic membrane (associated with 38.0 percent of the excess proportion of black infants with very low birth weights [95 percent confidence interval, 31.3 to 45.4 percent]); idiopathic preterm labor (20.9 percent of the excess [95 percent confidence interval, 16.0 to 26.4 percent]); hypertensive disorders (12.3 percent [95 percent confidence interval, 8.6 to 16.6]); and hemorrhage (9.8 percent [95 percent confidence interval, 5.5 to 13.5]). CONCLUSIONS: The higher proportion of black infants with very low birth weights is associated with a greater frequency of all major maternal conditions precipitating delivery among black women. Reductions in the disparity in birth weight between blacks and whites are not likely to result from any single clinical intervention but, rather, from comprehensive preventive strategies.

Relations over time between psychiatric and somatic disorders: the Stirling County Study.

A longitudinal study of a general population in Atlantic Canada provided information on associations between two broad categories of illness: somatic disorders and disorders involving depression and/or anxiety. Prevalence was investigated in a sample of 1,003 adults selected in 1952 and another sample of 1,094 adults selected in 1970. Using a cohort of 618 survivors from the 1952 sample who were followed up in 1968, the authors studied prevalence at the beginning and end of the 16-year period. Incidence was also investigated so that the strength of associations between prior illness of one type and subsequent illness of the other type could be assessed. Data were obtained by interviewing subjects with the same structured schedule at each time of investigation. In prevalence enumerations, psychiatric disorders were found to be significantly associated with somatic disorders. Prior somatic disorder was significantly associated with subsequent incidence of depression and/or anxiety and vice versa. The results did not, however, show one direction of influence ("psyche-to-soma" or "soma-to-psyche") to be markedly stronger than the other. The results mainly support the concept of "generalized vulnerability" and draw attention to the importance of recognizing comorbidity in diagnosis and clinical practice.

Depression and anxiety in relation to social status. A prospective epidemiologic study.

Longitudinal research in Stirling County, Atlantic Canada, indicated that during the 1950s and 1960s the prevalence of depression was significantly and persistently higher in the "low" socioeconomic status population than at other socioeconomic status levels. Anxiety was found to show a less clear picture. Incidence of depression after the study started was also higher among those who were initially in the low socioeconomic status group, supporting the view that the stress of poverty may be causally related to depression. There was also a trend for prior depression to be associated with subsequent downward social mobility, supporting the view that the concentration of depressed people at the lower end of the social hierarchy may result from handicapping aspects of the illness. Neither of these trends was statistically significant. More striking was evidence that, irrespective of socioeconomic status, depression carried a substantial risk for poor clinical course and outcome. Both depression and poverty tended to be chronic, and, accordingly, their association at the end of the study was influenced by their association at its beginning. The stability of the relationship between poverty and depression warrants the attention of caregivers and policymakers and raises new questions about strategies for the study of causal sequences.

Very low birth weight children: behavior problems and school difficulty in a national sample.

We addressed three questions concerning the behavioral and academic status of low and very low birth weight infants through a secondary analysis of the 1981 National Health Interview Survey--Child Health Supplement: (1) in children born with very low birth weight, what is the risk of behavior problems and school difficulty compared with that in heavier low birth weight and normal birth weight children? (2) What are the correlates of school difficulty? (3) Are behavior problems associated with school difficulty when variables are controlled for these correlates? The analysis revealed that 34% of very low birth weight children could be characterized as having school difficulty, compared with 20% and 14% of the other groups, respectively, and that they were more likely to have higher scores on the hyperactive subscale of the Behavior Problems Index. Although a broad array of sociodemographic factors correlated with school difficulty, very low birth weight and hyperactivity scores contributed independently to the risk of academic problems. We conclude that very low birth weight infants are at risk of having school problems that are in part associated with hyperactive behavior.

Chronic conditions, socioeconomic risks, and behavioral problems in children and adolescents.

Children with a chronic health condition have long been considered at excess risk for psychosocial morbidity. Despite an increasing prevalence of chronic childhood conditions and heightened concerns for the quality of life of the chronically ill, population-based studies of behavior problems among children with chronic physical conditions are rare. Findings on the epidemiology of behavior problems in a nationally representative sample of 11,699 children and adolescents aged 4 to 17 years in the United States are reported. Data included a 32-item parent-reported behavior problem index, measures of chronic childhood conditions, measures of school placement and performance, and sociodemographic variables. Analyses confirmed that chronic physical conditions were a significant risk factor for behavior problems, independent of sociodemographic variables. Among children these differences were observed across all subscales; among adolescents the largest differences were found for the Depression/Anxiety and Peer Conflict/Social Withdrawal subscales. Rates of extreme behavior problem scores (those in the top 10th percentile) were 1.55 times higher among children with a chronic health condition compared with children without a chronic condition (95% confidence interval 1.29 to 1.86). These independent odds were lowered to 1.44 when covariates for confounding were introduced via a multivariate logistic regression. Other independent risks included the absence of either biologic parent (odds ratio 2.05), male gender (1.53), low vs high family income (1.30), low vs high maternal education (1.51), and young vs old maternal age at childbirth (2.57). Chronic health conditions were also a major risk factor for placement in special education classes and having to repeat grades. Despite evidence for effective interventions, health services for children with chronic conditions--particularly mental health services--remain fragmented, signaling the need for increased attention to behavioral problems and their treatment among all health professionals caring for children.

Prodromes of depression and anxiety. The Stirling County study.

A longitudinal investigation of psychiatric epidemiology in a general population (the Stirling County study) has indicated that the incidence of depression and anxiety disorders is low relative to prevalence, because these disorders have long durations. In an average year approximately nine adults among 1,000 experience a first-ever episode of one of these disorders. Incident cases over the course of a 16-year follow-up were more likely to have had premonitory symptoms than to have been asymptomatic at the beginning of the study. Among the relatively small number of people who exhibited the clearest prodromal manifestations, incidence was 20 per 1,000 annually. It might be possible to intervene before such disorders become fully formed and persistent if the precursors are given attention.