Changes in millennial adolescent mental health and health-related behaviours over 10 years: a population cohort comparison study

Background There is evidence that mental health problems are increasing and substance use behaviours are decreasing. This paper aimed to investigate recent trends in mental ill health and health-related behaviours in two cohorts of UK adolescents in 2005 and 2015. Methods Prevalences in mental health (depressive symptoms, self-harm, anti-social behaviours, parent-reported difficulties) and health-related behaviours (substance use, weight, weight perception, sleep, sexual intercourse) were examined at age 14 in two UK birth cohorts; Avon Longitudinal Study of Parents and Children (ALSPAC, N = 5627, born 1991–92) and Millennium Cohort Study (MCS, N = 11 318, born 2000–02). Prevalences and trend estimates are presented unadjusted and using propensity score matching and entropy balancing to account for differences between samples. Results Depressive symptoms (9% to 14.8%) and self-harm (11.8% to 14.4%) were higher in 2015 compared with 2005. Parent-reported emotional difficulties, conduct problems, hyperactivity and peer problems were higher in 2015 compared with 2005 (5.7–8.9% to 9.7–17.7%). Conversely, substance use (tried smoking, 9.2% to 2.9%; tried alcohol, 52.1% to 43.5%, cannabis, 4.6% to 3.9%), sexual activity (2% to 0.9%) and anti-social behaviours (6.2–40.1% to 1.6–27.7%) were less common or no different. Adolescents in 2015 were spending less time sleeping (<8 h 5.7% to 11.5%), had higher body mass index (BMI) (obese, 3.8% to 7.3%) and a greater proportion perceived themselves as overweight (26.5% to 32.9%). The findings should be interpreted bearing in mind limitations in ability to adequately harmonize certain variables and account for differences in attrition rates and generalizability of the two cohorts. Conclusions Given health-related behaviours are often cited as risk factors for poor mental health, our findings suggest relationships between these factors might be more complex and dynamic in nature than currently understood. Substantial increases in mental health difficulties, BMI and poor sleep-related behaviours highlight an increasing public health challenge

Association Between Cannabis and Psychosis:Epidemiologic Evidence

Associations between cannabis use and psychotic outcomes are consistently reported, but establishing causality from observational designs can be problematic. We review the evidence from longitudinal studies that have examined this relationship and discuss the epidemiologic evidence for and against interpreting the findings as causal. We also review the evidence identifying groups at particularly high risk of developing psychosis from using cannabis. Overall, evidence from epidemiologic studies provides strong enough evidence to warrant a public health message that cannabis use can increase the risk of psychotic disorders. However, further studies are required to determine the magnitude of this effect, to determine the effect of different strains of cannabis on risk, and to identify high-risk groups particularly susceptible to the effects of cannabis on psychosis. We also discuss complementary epidemiologic methods that can help address these questions

Socioeconomic status, alcohol use and the role of social support and neighbourhood environment among individuals meeting criteria for a mental health problem: a cross-sectional study

PurposeIndicators of socioeconomic status (SES), such as education and occupational grade, are known to be associated with alcohol use but this has not been examined among individuals with a mental health problem. This study developed latent classes of SES, their associations with alcohol use, and examined the indirect effect via social support and neighbourhood environment.MethodsA secondary analysis of the 2014 Adult Psychiatric Morbidity Survey was conducted among participants with a mental health problem (N = 1,436). SES classes were determined using a range of indicators. Alcohol use was measured using the Alcohol Use Disorder Identification Test. Social support and neighbourhood neighbourhood environment were measured using validated questionnaires. A latent class analysis was conducted to develop SES classes. Multinomial logistic regression examined associations of SES and alcohol use. Structural equation models tested indirect effects via social support and neighbourhood environment.ResultsA four-class model of SES was best-fitting; “economically inactive, GCSE-level and lower educated, social renters”, “intermediate/routine occupation, GCSE-level educated, mixed owner/renters”, “retired, no formal education, homeowners”, and “professional occupation, degree-level educated, homeowners”. Compared to “professional occupation, degree-level educated, homeowners”, SES classes were more likely to be non-drinkers; odds were highest for “economically inactive, GCSE-level and lower educated, social renters” (OR = 4.96,95%CI 3.10–7.93). “Retired, no formal education, homeowners” were less likely to be hazardous drinkers (OR = 0.35,95%CI 0.20–0.59). Associations between “economically inactive, GCSE-level and lower educated, social renters” and “retired, no formal education, homeowners” and non- and harmful drinking via social support and neighbourhood environment were significant.ConclusionsIn contrast to the alcohol harms paradox, among individuals with a mental health problem, lower SES groups were more likely to be non-drinkers while no associations with harmful drinking were found. There is also a need to examine the alcohol harms paradox in the context of the area in which they live

Prospective Investigation of Video Game Use in Children and Subsequent Conduct Disorder and Depression Using Data from the Avon Longitudinal Study of Parents and Children

There is increasing public and scientific concern regarding the long-term behavioural effects of video game use in children, but currently little consensus as to the nature of any such relationships. We investigated the relationship between video game use in children, degree of violence in games, and measures of depression and a 6-level banded measure of conduct disorder. Data from the Avon Longitudinal Study of Parents and Children were used. A 3-level measure of game use at age 8/9 years was developed, taking into account degree of violence based on game genre. Associations with conduct disorder and depression, measured at age 15, were investigated using ordinal logistic regression, adjusted for a number of potential confounders. Shoot-em-up games were associated with conduct disorder bands, and with a binary measure of conduct disorder, although the strength of evidence for these associations was weak. A sensitivity analysis comparing those who play competitive games to those who play shoot-em-ups found weak evidence supporting the hypothesis that it is violence rather than competitiveness that is associated with conduct disorder. However this analysis was underpowered, and we cannot rule out the possibility that increasing levels of competition in games may be just as likely to account for the observed associations as violent content. Overall game exposure as indicated by number of games in a household was not related to conduct disorder, nor was any association found between shoot-em-up video game use and depression

Understanding alcohol use and changes in drinking habits among people with a severe mental illness: a qualitative framework analysis study

Introduction: Individuals with a severe mental illness (SMI) are more likely to drink at harmful levels or abstain. While it is known that drinking patterns change over time, the reasons for this among those with a SMI are unclear. This study aimed to (i) explore the experiences with alcohol, particularly in relation to mental health symptoms, and (ii) how drinking patterns have changed over time, among individuals who have a SMI diagnosis, who either currently drink alcohol or no longer drink.Methods: One-to-one semi-structured telephone interviews were conducted to address the study aims. Current drinkers' alcohol use was assessed using the Alcohol Use Disorder Identification Test. A framework analysis was used to address the study aims with a specific focus on the differences in the experiences with alcohol use between current and former drinkers.Results: 16 participants were interviewed, and five themes were developed. The analysis highlighted how alcohol was increasingly used to cope with (i) trauma, (ii) SMI-related symptoms, or (iii) stress. Among those with a SMI, non-drinking was facilitated through declines in SMI-related symptoms, previous negative consequences due to alcohol and changing the social environment. Current drinking habits were facilitated through changes in the reasons for drinking and adopting different alcohol moderation techniques.Discussion: Among those with a SMI diagnosis and who either currently drink alcohol or no longer drink, our findings support the self-medication hypothesis and drinking motives model. However, our findings indicate the need for further development of drinking to cope with a focus on symptoms of a SMI and trauma. Our findings also have implications on specialist alcohol and mental health services, the need to improve individuals' understanding of SMI, and the need to identify reasons for drinking among those with a recent diagnosis of a SMI

Changes in the prevalence and correlates of weight-control behaviors and weight perception in adolescents in the UK, 1986-2015

Importance: In the context of the growing prevalence of childhood obesity, behaviors aimed at weight loss and their psychological burden might be increasing. Objective: To investigate whether the prevalence of weight-control behaviors and weight perception, including their association with depressive symptoms, has changed in the 3 decades between 1986 and 2015. Design, Setting, and Participants: This study used data from repeated cross-sections from successive longitudinal birth cohort studies. These included general population samples of UK adolescents aged 14 to 16 years from 3 ongoing birth cohorts: the British Cohort Study 1970 (children born between April 5 and 11, 1970; data collected in 1986), the Avon Longitudinal Study of Parents and Children (mothers with expected delivery between April 1, 1991, and December 21, 1992; data collected in 2005), and the Millennium Cohort Study (children born between September 1, 2000, and January 11, 2002; data collected in 2015). A total of 22 503 adolescents with data available on at least 1 weight-control or weight-perception variable in midadolescence were included in the study. Data were analyzed from August 1, 2019, to January 15, 2020. Main Outcomes and Measures: Self-reported lifetime dieting and exercise for weight loss, current intentions about weight (doing nothing, lose weight, stay the same, gain weight), and weight perception (underweight, about the right weight, overweight) adjusted for body mass index. The secondary outcome was depressive symptoms. Exposures: The main exposure was time (ie, cohort); secondary exposures were weight-change behaviors and weight perception. Results: The study cohort included 22 503 adolescents (mean [SD] age, 14.8 [0.3] years; 12 061 girls [53.6%]; and 19 942 White individuals [89.9%]). A total of 5878 participants were from the British Cohort Study, 5832 were from the Avon Longitudinal Study of Parents and Children, and 10 793 were from the Millennium Cohort Study. In 2015, 4809 participants (44.4%) had dieted and 6514 (60.5%) had exercised to lose weight compared with 1952 (37.7%) and 344 (6.8%) in 1986. Furthermore, 4539 (42.2%) were trying to lose weight in 2015 compared with 1767 (28.6%) in 2005. Although girls were more likely to report these behaviors in all years, their prevalence increased more in boys over time (lifetime dieting in boys: odds ratio [OR], 1.79; 95% CI, 1.24-2.59; in girls: OR, 1.23; 95% CI, 0.91-1.66; currently trying to lose weight in boys: OR, 2.75; 95% CI, 2.38-3.19; in girls: OR, 1.70; 95% CI, 1.50-1.92). Adolescents also became more likely to overestimate their weight (boys describing themselves as overweight adjusting for body mass index, 2005 vs 1985 OR, 1.60; 95% CI, 1.17-2.19; 2015 vs 1985 OR, 1.36; 95% CI, 1.04-1.80; girls describing themselves as underweight, after adjusting for body mass index, 2015 vs 1986 OR, 0.51; 95% CI, 0.28-0.91). Girls who described themselves as overweight experienced increasingly greater depressive symptoms over time compared to girls who described their weight as about right (mean difference 1986, 0.32; 95% CI, 0.22-0.41; mean difference 2005, 0.33; 95% CI, 0.24-0.42; mean difference 2015, 0.56; 95% CI, 0.49-0.62). Conclusions and Relevance: These findings suggest that the growing focus on obesity prevention might have had unintended consequences related to weight-control behaviors and poor mental health. Public health campaigns addressing obesity should include prevention of disordered eating behaviors and be sensitive to negative impact on mental health

G = E:What GWAS Can Tell Us about the Environment

As our understanding of genetics has improved, genome-wide association studies (GWAS) have identified numerous variants associated with lifestyle behaviours and health outcomes. However, what is sometimes overlooked is the possibility that genetic variants identified in GWAS of disease might reflect the effect of modifiable risk factors as well as direct genetic effects. We discuss this possibility with illustrative examples from tobacco and alcohol research, in which genetic variants that predict behavioural phenotypes have been seen in GWAS of diseases known to be causally related to these behaviours. This consideration has implications for the interpretation of GWAS findings

Causal inference in Developmental Origins of Health and Disease (DOHaD) research

Studies of the developmental origins of health and disease (DOHaD) often rely on prospective observational data, from which associations between developmental exposures and outcomes in later life can be identified. Typically, conventional statistical methods are used in an attempt to mitigate problems inherent in observational data, such as confounding and reverse causality, but these have serious limitations. In this review, we discuss a variety of methods that are increasingly being used in observational epidemiological studies to help strengthen causal inference. These methods include negative controls, cross-contextual designs, instrumental variables (including Mendelian randomization), family-based studies, and natural experiments. Applications within the DOHaD framework, and in relation to behavioral, psychiatric, and psychological domains, are considered, and the considerable potential for expanding the use of these methods is outlined. </jats:p