Seasonal trends in depressive problems among United States children and adolescents: a representative population survey

Prospectively assessed summer mood status in major depression, recurrent with seasonal pattern: Evidence for SAD's construct validity

OBJECTIVE

Seasonal patterns are often undetectable in population-based depression studies, calling into question the existence of winter seasonal affective disorder (SAD). If SAD has construct validity, individuals with SAD should show spontaneous depression remission in the summer. Data are sparse on prospectively assessed summer mood status in confirmed SAD patients.

METHOD

We conducted prospective summer followup of community adults who, the winter before, were diagnosed with Major Depression, Recurrent with Seasonal Pattern on the Structured Clinical Interview for DSM-IV Axis I Disorders, developed a current SAD episode on the Structured Interview Guide for the Hamilton Rating Scale for Depression-Seasonal Affective Disorder Version (SIGH-SAD), and enrolled in a clinical trial comparing group cognitive-behavioral therapy for SAD and light therapy. In July/August after treatment, 143/153 (93.5 %) participants provided data on the SIGH-SAD, the Beck Depression Inventory-Second Edition, and the Longitudinal Interval Followup Evaluation (LIFE).

RESULTS

Summer mean depression scores were in the normal range, with the substantial majority in remission across different measures. On the LIFE, 113/143 (79.0 %) experienced complete summer remission, 19/143 (13.3 %) experienced partial summer remission, and 11/143 (7.7 %) had major depression in the summer. Depression scores were significantly lower at summer than post-treatment in both treatments, indicating incomplete treatment response.

LIMITATIONS

This was a single-site study with a relatively homogeneous sample.

CONCLUSIONS

Supporting construct validity for SAD, the substantial majority experienced complete summer remission, with a minority in partial remission and a very small minority in episode. Both treatments left residual symptoms at treatment endpoint compared to summer.

Effect of Hometown Seasonality on Undergraduate Students' Risk of Developing Seasonal Affective Disorder

Seasonal affective disorder (SAD) is a prevalent and potentially serious medical condition. Young adults are at particularly high risk. However, it is unknown if college students whose hometowns are in geographic areas with less seasonal variability, such as in the state of Hawai'i, are particularly vulnerable if they attend schools in areas with seasonal variability. An adapted version of the Seasonal Patterns Assessment Questionnaire (SPAQ) was administered to students at 3 universities to test this hypothesis. Surveys were administered twice: a baseline (T0) assessment in the fall and a follow-up (T1) assessment in the winter and were administered in the second month of each semester. A linear regression model was constructed to identify potential risk factors for developing seasonal fluctuations in mood (SPAQ scores T1-T0). Study subjects (n=115) from non-seasonal hometowns had a 1.6-point greater increase in SPAQ score than students from seasonal hometowns (-0.26 ± 3.88 vs 1.35 ± 3.03; P =.01). This difference is independent of demographic and lifestyle predictors (linear regression coefficient: β = 1.73; standard error = 0.68; P =.012). Interestingly, SPAQ score changes of students from seasonal hometowns did not differ significantly from 0 (t = -0.97; P =.33), indicating that they did not generally experience seasonal shifts in depressive symptoms. Students from less seasonal hometowns and counselors at seasonal institutions should be aware that these students could be more at risk of developing depressive symptoms and address these concerns before interfering with students' daily and academic lives.

Longitudinal Coupling of Depression in Parent-Adolescent Dyads: Within- and Between-Dyad Effects Over Time

The present work evaluated reciprocal, within-dyad associations between parent-adolescent depressive symptoms across two independent samples (N=327 and N=435 dyads, respectively; approximately 85% biological mothers) assessed every three months for two (Study 1) to three (Study 2) years. Results of random intercept cross-lagged panel models converged to support positive contemporaneous patterns of co-fluctuation in parent and adolescent depression, such that within-person deviations in parental depression were associated with same direction within-person deviations in adolescent depression at the same timepoint. In contrast, within-person fluctuations in parent depression did not predict prospective within-person fluctuations in adolescent depression, or vice versa, across the follow-up period. Results held across boys and girls, as well as dyads with and without a parental history of depressive disorder. Overall, findings advance knowledge by demonstrating that, after accounting for between-person/dyad variance, parent and adolescent depression demonstrate contemporaneous co-fluctuations, but do not demonstrate within-dyad reciprocity over time.

Crisis support-seeking behavior and temperature in the United States: Is there an association in young adults and adolescents?

BACKGROUND

Mounting evidence demonstrates the relationship between high temperatures and adverse mental health outcomes. Yet, no study has examined the influence of temperature on crisis support-seeking behavior among youth in large urban areas.

METHODS

Crisis Text Line (CTL) is a text messaging service that provides crisis interventions for support-seeking individuals for a range of mental-health outcomes in the United States. We applied a distributed lag non-linear modeling technique to assess the short-term impacts of daily maximum and minimum temperature on crisis-related events in four metropolitan locations in the USA.

RESULTS

There were multiple positive associations in three of the four study locations that demonstrate crisis help-seeking behavior increased during anomalously warm conditions.

CONCLUSIONS

This study suggests that there is a significant association between high minimum or maximum temperatures and crisis help-seeking behaviors in young adults and adolescents in urban areas in the United States.

Exposure-lag-response association between sunlight and schizophrenia in Ningbo, China

Previous studies found that mental disorders such as bipolar disorder, seasonal affective disorder and schizophrenia, often show seasonal variability, which usually be attributed to the variations in the number of natural sunlight. However, few studies have been conducted on the acute effects of exposure to sunlight on the onset of these disease. The aim of this study was to evaluate the exposure-response relationship between sunshine duration and the hospital admissions for schizophrenia. We obtained data on hospital admissions for schizophrenia from the largest psychiatric hospital in Ningbo, China, during 2012-2016. A Distributed lag non-linear model was used to estimate the exposure-lag-response relationship between sunlight and schizophrenia. We calculated the effects of short and long sunshine duration, defined using the cutoffs at the 1st and 99th sunshine duration percentiles. We detected significant and non-linear associations between sunlight and schizophrenia, and the overall estimated relative risk (RR) for a lag of 0-21 days was 1.45 (95% CI: 1.07, 1.97) and 1.41(95% CI: 0.72, 2.75) for short and long sunshine duration, respectively. The burden of schizophrenia was greater during periods with short sunshine duration than during periods with long sunshine duration, with the AFs of 19.94% (95% CI: 8.65%, 28.24%) and 2.12% (95% CI: -2.70%, 5.57%), respectively. The female and people more than 45 years old were most susceptible to these effects. We repeated our analysis by using global solar radiation as a continuous exposure variable of sunlight intensity in the model, and the result shows that the female and middle-aged and eldly patients were also susceptible to the effects of low levels of global solar radiation. Our findings suggest that there may be a relationship between lack of exposure to sunlight and increased risk of hospital admissions for schizophrenia. Policymakers and doctors should promote further understanding of the health benefits of sunlight and take effective measures to prevent schizophrenia.

No evidence of seasonal variation in mild forms of depression

BACKGROUND AND OBJECTIVES

Seasonal Affective Disorder (SAD) is ubiquitous in popular culture and has influenced psychiatric diagnosis with the inclusion of the seasonal pattern modifier for the Major Depressive Episode in DSM. However, recent research has not supported the association of Major Depressive Episode with seasonal changes. The present study was conducted to determine if a seasonally-related pattern of occurrence of mild variants of depression could be demonstrated in a population-based study.

METHODS

This is a cross-sectional U.S. survey of adults who completed the PHQ-8 Depression Scale with mild depression defined using a PHQ-8 cut score and a second model based on the DSM-5 diagnosis, Depression with insufficient symptoms. Regression models were used to determine if either variant of mild depression was related to season, latitude, or measures of daylight hours.

RESULTS

Neither measure of mild depression was related to daylight hours or its proxy measures.

LIMITATIONS

Screening instruments for depression, even if consistent with DSM-5 diagnostic criteria, do not allow a formal diagnosis of depression or the exclusion of similar-appearing disorders. Current depression symptoms but not duration of depressive episode is measured.

CONCLUSIONS

Mild depression is not related to seasonal changes or proxy measures of light exposure. The findings cast doubt on light deficiency as a causal factor of depressive disorders, which underpins the inclusion of the seasonal pattern modifier in DSM-5 and light supplementation as a treatment modality.

Adolescents in crisis: A geographic exploration of help-seeking behavior using data from Crisis Text Line

Nearly 3 out of 4 all lifelong mental disorders occur by the age of twenty-four. Remote crisis support holds great potential in filling a critical gap in complementing and expanding access to mental health services for acute episodes of mental distress in adolescents and young adults; yet little is understood about the individual factors that influence help-seeking behavior in this group. Recent evidence suggests technology-based mental health services have high acceptability among youth and may be used to treat anxiety and depression. The objective of this study was to examine county-level help-seeking behavior among adolescents and young adults using Crisis Text Line (CTL). CTL is a free, text-based crisis counseling service that has been available nationally since 2013. Spatial error regression was used to (1) identify the individual-level factors that correlate with help-seeking behavior for depression, anxiety, and suicidal thoughts and (2) to explore the geographic trends in text-based help-seeking behavior between adolescents and young adults across the rural-urban continuum. Increased rates of text-based help-seeking occurred in counties with higher mean household incomes, higher divorce rates, and lower residential stability. Rurality was the strongest predictor for low rates of help-seeking, and this finding is particularly concerning in light of elevated rates of suicide among rural counties. Rural communities, particularly those with low support-seeking behavior and comparatively high suicide rates, should be the target of future research and outreach.

Short photoperiod condition increases susceptibility to stress in adolescent male rats

The seasonality of depressive symptoms is prevalent in children and adolescents. However, the mechanisms that underlie such susceptibility to seasonal influences on mood disorders are unclear. We examined the effects of a short photoperiod condition on the susceptibility to subchronic unpredictable mild stress (SCUS) and rhythmic alterations of plasma corticosterone (CORT), melatonin, and neuropeptide Y (NPY) in adolescent male rats. Compared with the 12h/12h light/dark photoperiod control (CON) rats, the 8h/16h photoperiod SCUS rats exhibited significant anhedonia, a core symptom of human depression, together with a blunted diurnal rhythm and elevation of 24h CORT, melatonin, and NPY levels. The 8h/16h photoperiod condition also blunted the rhythmicity of CORT, caused a phase inversion of melatonin, and caused a phase delay of NPY compared with 12h/12h CON rats. Such abnormalities of plasma CORT, NPY, and melatonin might cause adolescent individuals to present higher stress reactivity and greater vulnerability to stress over their lifetimes. The present study provides evidence of the susceptibility to the seasonality of stress-related disorders in adolescence.

Sleep characteristics, chronotype and winter depression in 10-20-year-olds in northern European Russia

The purpose of this work was to examine the relationships between geographical coordinates and the prevalence of winter depression (SADW ), and to compare the sleep characteristics and chronotype of youths with and without SADW . We conducted a cross-sectional study of self-reported sleep characteristics, chronotype and winter depression in northern European Russia. Two questionnaires, the Munich Chronotype Questionnaire (MCTQ) and the Seasonal Pattern Assessment Questionnaire (SPAQ), were administered to a total of 3435 adolescents aged 10-20 years (1517 males and 1918 females). The prevalence of SADW in the study population was 8.4% and sub-SADW 11.8%. Four variables predicted the likelihood of SADW in youths: sex [higher in females: odds ratio (OR): 1.87, P < 0.0001], age (increases with age: OR: 1.09, P < 0.001), latitude (higher in the North: OR: 1.49, P < 0.029) and position in the time zone (higher in the West: OR: 1.61, P < 0.001). Later sleeping and waking, longer sleep latencies, more severe sleep inertia, shorter total sleep times and lower sleep efficiencies were observed in both males and females with SADW . The influence of SADW on sleep characteristics was more pronounced on school days. Significant phase delays of the sleep-wake rhythm and severe social jetlag (the difference between the mid-point of sleep phase at weekends and on workdays) were observed in females with SADW , but not in males. There are significant differences in sleep characteristics and chronotype between people with SADW and no-SAD. We demonstrate that both latitude of residence and location within the time zone are significant predictors of SADW in young inhabitants of the North.

Depressive symptoms are associated with excess weight and unhealthier lifestyle behaviors in urban adolescents

BACKGROUND

Adolescence is a critical period for the development of depressive symptoms and obesity. This study examined the association of depressive symptoms with standardized BMI (BMI z-score), lifestyle behaviors, and self-efficacy measures in a sample of urban adolescents.

METHODS

A school-based study was conducted among adolescents (N=1508) enrolled from 11 public schools. Depressive symptoms were assessed with Kandel's depressive symptoms scale for adolescents. Fruit and vegetable intake and intake of energy-dense foods were assessed by a short food frequency questionnaire. Sedentary behavior and physical activity (PA) were obtained by self-report. Height and weight were measured directly and BMI z-scores were calculated. Mixed-effects models were used to examine the association of depressive symptoms with BMI z-score and lifestyle behaviors, accounting for clustering at school level and adjusting for confounders. Self-efficacy measures were evaluated as potential mediators.

RESULTS

The sample was 53% female, 75% Hispanic, and 82% US born, with a mean age of 13.9 years. Higher depressive symptoms were associated with higher BMI z-score (β=0.02; p=0.02), intake of energy-dense foods (β=0.42; p<0.001), and sedentary behavior (β=0.48; p<0.001), but lower PA (β=-0.03; p=0.01). There was an interaction by gender in the association of depressive symptoms and PA. Self-efficacy mediated the association of depressive symptoms and PA.

CONCLUSIONS

Obesity prevention and treatment programs should consider addressing the role of negative emotions as part of their preventive strategies.

Two longterm studies of seasonal variation in depressive symptoms among community participants

BACKGROUND

There is evidence that seasonal variation in depressive symptoms is common in the population. However, research is limited by a reliance on longterm retrospective methods.

METHODS

Seasonal patterns were tested in two samples of community participants recruited in separate prospective studies in the Midwestern (n=556 males/females) and Pacific Northwestern (n=206 males) United States. Participants completed self-report measures of depressive symptoms 10-19 times from ages 14 to 36 years (n=8316 person observations). These data were compared with local meteorological conditions (e.g., solar radiation) recorded across the 2 weeks prior to each self-report.

RESULTS

In within-subjects analyses, participants' depressive symptoms and the probability of clinically significant symptoms varied with the time of year, as hypothesized (highest in the weeks of early Winter; lowest in early Fall). However, effect sizes were modest and were not explained by recent sunlight or other meteorological conditions.

LIMITATIONS

Samples were not nationally representative. Participants did not complete retrospective reports of seasonal depression or measures of current vegetative symptoms.

CONCLUSIONS

Neither time of the year nor recent seasonally linked meteorological conditions were powerful influences on depressive symptoms experienced by community populations in relevant geographic regions. Prior studies may have overestimated the prevalence and significance of seasonal variation in depressive symptoms for the general population.

Seasonality in seeking mental health information on Google

BACKGROUND

Population mental health surveillance is an important challenge limited by resource constraints, long time lags in data collection, and stigma. One promising approach to bridge similar gaps elsewhere has been the use of passively generated digital data.

PURPOSE

This article assesses the viability of aggregate Internet search queries for real-time monitoring of several mental health problems, specifically in regard to seasonal patterns of seeking out mental health information.

METHODS

All Google mental health queries were monitored in the U.S. and Australia from 2006 to 2010. Additionally, queries were subdivided among those including the terms ADHD (attention deficit-hyperactivity disorder); anxiety; bipolar; depression; anorexia or bulimia (eating disorders); OCD (obsessive-compulsive disorder); schizophrenia; and suicide. A wavelet phase analysis was used to isolate seasonal components in the trends, and based on this model, the mean search volume in winter was compared with that in summer, as performed in 2012.

RESULTS

All mental health queries followed seasonal patterns with winter peaks and summer troughs amounting to a 14% (95% CI=11%, 16%) difference in volume for the U.S. and 11% (95% CI=7%, 15%) for Australia. These patterns also were evident for all specific subcategories of illness or problem. For instance, seasonal differences ranged from 7% (95% CI=5%, 10%) for anxiety (followed by OCD, bipolar, depression, suicide, ADHD, schizophrenia) to 37% (95% CI=31%, 44%) for eating disorder queries in the U.S. Several nonclinical motivators for query seasonality (such as media trends or academic interest) were explored and rejected.

CONCLUSIONS

Information seeking on Google across all major mental illnesses and/or problems followed seasonal patterns similar to those found for seasonal affective disorder. These are the first data published on patterns of seasonality in information seeking encompassing all the major mental illnesses, notable also because they likely would have gone undetected using traditional surveillance.

Seasonal trends in depressive symptoms in adolescents with type 1 diabetes

Adolescents with type 1 diabetes reported more clinically significant depressive symptoms in the spring/summer months (22% in April-September) than in the fall/winter months (11% in October-March) (χ(2)=5.67, p=.018). This seasonal pattern was stronger in low-income adolescents than in adolescents from higher-income families.