The prevalence of mental ill health is increasing in young people worldwide, with rising referrals to child and adolescent mental health services (CAMHS). The numbers and proportions of the youth population who present to CAMHS, however, including how those figures are changing over time, are unclear. Understanding trends in mental health service contacts for young people over time is crucial mental health surveillance data.

Our aim was to calculate both the lifetime and annual prevalence of CAMHS contact in Wales for young people up to age 18 years.

Using linked Welsh administrative healthcare records, we calculated the annual prevalence of CAMHS contacts between 2004 and 2023. We also calculated the lifetime prevalence of CAMHS contacts for sequential annual birth cohorts born between 1991 and 2005 and followed to age 18 (between 2009 and 2023).

In 2004, 0.8% (n = 4665) of the total child and adolescent population were in contact with CAMHS. By 2022, this had risen nearly five-fold to 3.9% (n = 19 870) of the total child and adolescent population. Among the 1991 birth cohort who turned 18 in 2009, 5.8% had contact with CAMHS at some stage in childhood or adolescence. For individuals born in 2005 who turned 18 in 2023, this figure had risen to 20.2%.

The number of the young people in contact with CAMHS has increased dramatically over the past 15 years, from 1 in 17 young people who turned 18 in 2009 to 1 in 5 young people who turned 18 in 2023.

Whether the recent rise in adolescent self-reported depressive symptoms is influenced by changing reporting behavior is much debated. Most studies use observed sum scores to document trends but fail to assess whether their measures are invariant across time, a prerequisite for meaningful inferences about change. We examined whether measurement noninvariance, indicative of changing perceptions and reporting of symptoms, may influence the assessment of time trends in adolescent depressive symptoms.

Data stem from the nationwide repeated cross-sectional Ungdata-surveys (2010–2019) of 560 712 responses from adolescents aged 13 to 19 years. Depressive symptoms were measured with the Kandel and Davies' six-item Depressive Mood Inventory. Using structural equation modeling, we examined measurement invariance across time, gender and age, and estimated the consequences of noninvariance on cross-cohort time trends.

Across most conditions, the instrument was found measurement invariant across time. The few noninvariant parameters detected had negligible impact on trend estimates. From 2014, latent mean depressive symptom scores increased among girls. For boys, a U shaped pattern was detected, whereby an initial decrease in symptoms was followed by an increase from 2016. Larger issues of noninvariance were found across age in girls and between genders.

From a measurement perspective, the notion that changed reporting of symptoms has been an important driver of secular trends in depressive symptoms was not supported. Thus, other causes of these trends should be considered. However, noninvariance across age (in girls) and gender highlights that depressive symptoms are not necessarily perceived equivalently from early to late adolescence and across gender.

Previous epidemiological evidence identified a concerning increase in behavioural problems among young children from 1997 to 2008 in Brazil. However, it is unclear whether behavioural problems have continued to increase, if secular changes vary between sociodemographic groups and what might explain changes over time. We aimed to monitor changes in child behavioural problems over a 22-year period from 1997 to 2019, examine changing social inequalities and explore potential explanations for recent changes in behavioural problems between 2008 and 2019.

The Child Behaviour Checklist was used to compare parent-reported behavioural problems in 4-year-old children across three Brazilian birth cohorts assessed in 1997 (1993 cohort, n = 633), 2008 (2004 cohort, n = 3750) and 2019 (2015 cohort, n = 577). Response rates across all three population-based cohorts were over 90%. Moderation analyses tested if cross-cohort changes differed by social inequalities (demographic and socioeconomic position), while explanatory models explored whether changes in hypothesized risk and protective factors in prenatal development (e.g., smoking during pregnancy) and family life (e.g., maternal depression and harsh parenting) accounted for changes in child behavioural problems from 2008 to 2019.

Initial increases in child behavioural problems from 1997 to 2008 were followed by declines in conduct problems (mean change = −2.75; 95% confidence interval [CI]: −3.56, −1.94; P < 0.001), aggression (mean change = −1.84; 95% CI: −2.51, −1.17; P < 0.001) and rule-breaking behaviour (mean change = −0.91; 95% CI: −1.13, −0.69 P < 0.001) from 2008 to 2019. Sex differences in rule-breaking behaviour diminished during this 22-year period, whereas socioeconomic inequalities in behavioural problems emerged in 2008 and then remained relatively stable. Consequently, children from poorer and less educated families had higher behavioural problems, compared to more socially advantaged children, in the two more recent cohorts. Changes in measured risk and protective factors partly explained the reduction in behavioural problems from 2008 to 2019.

Following a rise in child behavioural problems, there was a subsequent reduction in behavioural problems from 2008 to 2019. However, social inequalities increased and remained high. Continued monitoring of behavioural problems by subgroups is critical for closing the gap between socially advantaged and disadvantaged children and achieving health equity for the next generation.

In Brazil, national estimates of childhood malnutrition have not been updated since 2006. The use of health information systems is an important complementary data source for analysing time trends on health and nutrition. This study aimed to examine temporal trends and socio-demographic inequalities in the prevalence of malnutrition in children attending primary health care services between 2009 and 2017.

Time trends study based on data from Brazil’s Food and Nutrition Surveillance System. Malnutrition prevalence (stunting, wasting, overweight and double burden) was annually estimated by socio-demographic variables. Prais–Winsten regression models were used to analyse time trends. Annual percent change (APC) and 95 % CI were calculated.

Primary health care services, Brazil.

Children under 5 years old.

In total, 15,239,753 children were included. An increase in the prevalence of overweight (APC = 3·4 %; P = 0·015) and a decline in the prevalence of wasting (–6·2 %; P = 0·002) were observed. The prevalence of stunting (–3·2 %, P = 0·359) and double burden (–1·4 %, P = 0·630) had discrete and non-significant reductions. Despite the significant reduction in the prevalence of undernutrition among children in the most vulnerable subgroups (black, conditional cash transfer’s recipients and residents of poorest and less developed areas), high prevalence of stunting and wasting persist alongside a disproportionate increase in the prevalence of overweight in these groups.

The observed pattern in stunting (high and persistent prevalence) and increase in overweight elucidate setbacks in advances already observed in previous periods and stresses the need for social and political strategies to address multiple forms of malnutrition.

There is growing evidence that mental health literacy has improved in western countries in recent years. The question arises as to whether this trend is paralleled by an improvement of attitudes towards people with mental illness.

To examine the development of mental health literacy and the desire for social distance towards people with schizophrenia and major depressive disorder in Eastern Germany over a time period of eight years.

A trend analysis was carried out using data from two population surveys conducted in the eastern part of Germany in 1993 and 2001. By means of a fully structured interview psychiatric labelling, causal beliefs, help-seeking and treatment recommendations as well as the desire for social distance was assessed.

While there was an increase in the mental health literacy of the public, the desire for social distance from people with major depression and schizophrenia remained unchanged or even increased.

The assumption underlying a number of anti-stigma campaigns, namely that educating people about mental disorders may automatically lead to the improvement of their attitudes towards the mentally ill, appears questionable.

To measure change in price of food groups over time (1995–2030) in Brazil, considering the Brazilian Dietary Guidelines’ recommendations.

Data from the Household Budget Survey (2008–2009 HBS) and the National System of Consumer Price Indexes (NSCPI) were used to create a data set containing monthly prices for the foods and beverages most consumed in the country (n 102), from January 1995 to December 2017. Data on price of foods and beverages from 2008–2009 HBS (referring to January 2009) were used to calculate real price over time using the monthly variation in prices from NSCPI. All prices were deflated to December 2017. Foods and beverages were classified following the Brazilian Dietary Guidelines’ recommendations. The monthly price for each food group and subgroup was used to analyse changes in prices from 1995 to 2017 and to forecast prices up to 2030 using fractional polynomial models.

Brazil.

National estimates of foods and beverages purchased for Brazil.

In 1995, ultra-processed foods were the most expensive group (R$ 6·51/kg), followed by processed foods (R$ 6·44/kg), then unprocessed or minimally processed foods and culinary ingredients (R$ 3·45/kg). Since the early 2000s, the price of ultra-processed foods underwent successive reductions, becoming cheaper than processed foods and reducing the distance between it and the price of the other group. Forecasts indicate that unhealthy foods will become cheaper than healthy foods in 2026.

Food prices in Brazil have changed unfavourably considering the Brazilian Dietary Guidelines’ recommendations. This may imply a decrease in the quality of the population’s diet.

There is a growing concern about the mental health of children and young people (CYP) in the UK, with increasing demand for counselling services, admissions for self-harm and referrals to mental health services. We investigated whether there have been similar recent trends in selected mental health outcomes among CYP in national health surveys from England, Scotland and Wales.

Data were analysed from 140 830 participants (4–24 years, stratified into 4–12, 13–15, 16–24 years) in 36 national surveys in England, Scotland and Wales, 1995–2014. Regression models were used to examine time trends in seven parent/self-reported variables: general health, any long-standing health condition, long-standing mental health condition; Warwick–Edinburgh Mental Wellbeing Score (WEMWBS), above-threshold Strengths and Difficulties Questionnaire Total (SDQT) score, SDQ Emotion (SDQE) score, General Health Questionnaire (GHQ) score.

Across all participants aged 4–24, long-standing mental health conditions increased in England (0.8–4.8% over 19 years), Scotland (2.3–6.0%, 11 years) and Wales (2.6–4.1%, 7 years) (all p < 0.001). Among young children (4–12 years), the proportion reporting high SDQT and SDQE scores decreased significantly among both boys and girls in England [SDQE: odds ratio (OR) 0.97 (0.96–0.98), p < 0.001] and girls in Scotland [SDQE: OR 0.96 (0.93–0.99), p = 0.005]. The proportion with high SDQE scores (13–15 years) decreased in England [OR 0.98 (0.96–0.99), p = 0.006] but increased in Wales [OR 1.07 (1.03–1.10), p < 0.001]. The proportion with high GHQ scores decreased among English women (16–24 years) [OR 0.98 (0.98–0.99), p = 0.002].

Despite a striking increase in the reported prevalence of long-standing mental health conditions among UK CYP, there was relatively little change in questionnaire scores reflecting psychological distress and emotional well-being.

Whether the incidence of eating disorders in Western, industrialized countries has changed over time has been the subject of much debate. The purpose of this primary-care study was to examine changes in the incidence of eating disorders in The Netherlands during the 1980s, 1990s and 2000s.

A nationwide network of general practitioners (GPs), serving a representative sample (~1%) of the total Dutch population, recorded newly diagnosed patients with anorexia nervosa (AN) and bulimia nervosa (BN) in their practice during 1985–1989, 1995–1999, and 2005–2009. GPs are key players in the Dutch healthcare system, as their written referral is mandatory in order to get access to specialized (mental) healthcare, covered by health insurance. Health insurance is virtually universal in The Netherlands (99% of the population). A substantial number of GPs participated in all three study periods, during which the same case identification criteria were used and the same psychiatrist was responsible for making the final diagnoses. Incidence rates were calculated and for comparison between periods, incidence rate ratios.

The overall incidence rate of BN decreased significantly in the past three decades (from 8.6 per 100 000 person-years in 1985–1989 to 6.1 in 1995–1999, and 3.2 in 2005–2009). The overall incidence of AN remained fairly stable during three decades, i.e. 7.4 per 1 00 000 person-years in 1985–1989, 7.8 in 1995–1999, and 6.0 in 2005–2009.

The incidence rate of BN decreased significantly over the past three decades, while the overall incidence rate of AN remained stable.

To assess seven-year time trends in energy balance-related behaviours in 14-year-old adolescents living in an urban area and to examine the influence of educational level and ethnicity on these time trends.

Second grade students (mean age 13·6 years) filled in questionnaires about the energy balance-related behaviours of breakfast consumption, fruit and vegetable consumption, physical activity and screen-time behaviour from school years 2006–2007 to 2012–2013. Energy balance-related behaviours were dichotomized and logistic regression analyses were used to examine time trends in healthy energy balance-related behaviours, including interaction terms for educational level and ethnicity.

Secondary schools in Amsterdam, the Netherlands.

Per school year, 2185–3331 children participated. The total sample included 19 244 students of Dutch, Surinamese, Turkish and Moroccan ethnic background.

A significant linear increase was found for positive screen-time behaviour (<2 h/d; OR per year=1·04; 95 % CI 1·03, 1·06). For daily vegetable consumption a non-linear negative trend was observed (school year 2012–2013 v. 2006–2007: OR=0·90; 95 % CI 0·80, 1·00). Time trends in screen time were significantly different across educational levels (P-interaction=0·002) and ethnic backgrounds (P<0·001), as were time trends in daily fruit consumption (P=0·017 and P=0·018, respectively) and, for ethnicity, trends in daily vegetable consumption (P<0·001).

The increase in positive screen-time behaviour is a positive finding. However, discouraging screen time and promoting other healthy behaviours, more specifically daily fruit and vegetable consumption, remain important particularly among adolescents enrolled in pre-vocational education and of non-Dutch ethnic background.

Little is known about whether particular suicide methods have contributed differently to the recent unfavourable suicide mortality trends in Japan. Analysing such trends may shed light on the effect of potentially preventable factors, such as the impact of restricting access to certain popular suicide methods, on overall rates. Therefore, we assessed recent trends in method-specific suicide by gender and age in Japan.

Suicide mortality and population data between 1990 and 2011 were obtained from the Vital Statistics of Japan and used to calculate method-specific mortality rates. Suicide methods were divided into seven groups: overdose, gases, hanging, drowning, cutting, jumping and other means. Age was divided into four groups: 15–24, 25–44, 45–64 and 65+ years. We applied joinpoint regression to the data and quantified the observed changes.

The results of the joinpoint regression analyses showed a sharp increase in overall suicide rates for males and females of all ages until the late 1990s. Suicide from hanging and jumping, in particular, contributed to this increase. After 2000, an increasing trend in overall suicide rates in both males and females aged 15–24 and 25–44 years was observed, with overdose, gases and hanging contributing to this increasing trend.

Our findings revealed that different suicide methods varied in their contribution to the recent overall suicide transition in Japan. Regarding factors associated with the recent increase in suicides by overdose, gases, hanging and jumping, further research is needed in order to promote and implement effective means restriction strategies.

Data on the prevalence of birth defects and neural tube defects (NTD) in Latin America are limited. The present review summarizes NTD prevalence and time trends in Latin American countries and compares pre- and post-fortification periods to assess the impact of folic acid fortification in these countries.

We carried out a literature review of studies and institutional reports published between 1990 and 2010 that contained information on NTD prevalence in Latin America.

NTD prevalence in Latin American countries varied from 0·2 to 9·6 per 1000 live births and was influenced by methods of ascertainment. Time trends from Bogota, Costa Rica, Dominican Republic, Guatemala City, Mexico and Puerto Rico showed average annual declines of 2·5 % to 21·8 %. Pre- and post-fortification comparisons were available for Argentina, Brazil, Chile, Costa Rica, Puerto Rico and Mexico. The aggregate percentage decline in NTD prevalence ranged from 33 % to 59 %.

The present publication is the first to review data on time trends and the impact of folic acid fortification on NTD prevalence in Latin America. Reported NTD prevalence varied markedly by geographic region and in some areas of Latin America was among the lowest in the world, while in other areas it was among the highest. For countries with available information, time trends showed significant declines in NTD prevalence and these declines were greater in countries where folic acid fortification of staples reached the majority of the population at risk, such as Chile and Costa Rica.

Official suicide statistics for England are based on deaths given suicide verdicts and most cases given an open verdict following a coroner's inquest. Previous research indicates that some deaths given accidental verdicts are considered to be suicides by clinicians. Changes in coroners' use of different verdicts may bias suicide trend estimates. We investigated whether suicide trends may be over- or underestimated when they are based on deaths given suicide and open verdicts.

Possible suicides assessed by 12 English coroners in 1990/91, 1998 and 2005 and assigned open, accident/misadventure or narrative verdicts were rated by three experienced suicide researchers according to the likelihood that they were suicides. Details of all suicide verdicts given by these coroners were also recorded.

In 1990/91, 72.0% of researcher-defined suicides received a suicide verdict from the coroner, this decreased to 65.4% in 2005 (ptrend < 0.01); equivalent figures for combined suicide and open verdicts were 95.4% (1990/91) and 86.7% (2005). Researcher-defined suicides with a verdict of accident/misadventure doubled over that period, from 4.6% to 9.1% (p < 0.01). Narrative verdict cases rose from zero in 1990/91 to 25 in 2005 (4.2% of researcher-defined suicides that year). In 1998 and 2005, 50.0% of the medicine poisoning deaths given accidental/misadventure verdicts were rated as suicide by the researchers.

Between 1990/91 and 2005, the proportion of researcher-defined suicides given a suicide verdict by coroners decreased, largely due to an increased use of accident/misadventure verdicts, particularly for deaths involving poisoning. Consideration should be given to the inclusion of ‘accidental’ deaths by poisoning with medicines in the statistics available for monitoring suicides rates.

To determine trends in prevalence of overweight and obesity in Kuwaiti adults, and to examine their association with selected sociodemographic and lifestyle factors.

Analysis of cross-sectional population survey data from the Kuwait National Nutrition Surveillance System.

Social and health facilities in Kuwait.

Males (n 17 491) and females (n 21 120) aged 20–69 years attending registration for employment or pensions, or Hajj Pilgrimage health check-ups, or parents accompanying their children for immunization 1998 through 2009. Sociodemographic, lifestyle and anthropometric data were collected.

Prevalence of BMI ≥ 25 kg/m2 rose from 61·8 % and 59·3 % in females and males respectively, peaked in 2004–2005 (81·4 % and 79·2 %) and fell slightly in 2008–2009 (77·3 % and 77·4 %). Obesity prevalence in females exceeded males for all years and age groups; by 2009, it had increased by 11·3 % in males and 14·6 % in females. Overweight and obesity prevalences in both genders increased until 2004–2005 but fell thereafter, with significant falls for females in 2008–2009. Logistic and linear regression analyses confirmed these temporal changes for both prevalence and BMI in both genders. The odds of obesity increased with age until the fifth decade for both genders and then declined significantly for males. Education level was negatively associated with obesity prevalence in females, while participation in leisure-time exercise was negatively associated with obesity prevalence in males.

Although the combined prevalence of overweight and obesity (BMI ≥ 25 kg/m2) seemed to decrease from 2005 to 2009 among Kuwaiti adults, further research to clarify the identified confounders and continued monitoring are needed to confirm the decrease observed.

To analyse (i) differences in beverage pattern among Norwegian children in 2001 and 2008; (ii) beverage intake related to gender, parental education and family composition; and (iii) potential disparities in time trends among the different groups.

Within the Fruits and Vegetables Make the Marks (FVMM) project, 6th and 7th grade pupils filled in a questionnaire about frequency of beverage intake (times/week) in 2001 and 2008.

Twenty-seven elementary schools in two Norwegian counties.

In 2001 a total of 1488 and in 2008 1339 pupils participated.

Between 2001 and 2008, a decreased consumption frequency of juice (from 3·6 to 3·4 times/week, P = 0·012), lemonade (from 4·8 to 2·5 times/week, P < 0·001) and regular soft drinks (from 2·7 to 1·6 times/week, P < 0·001), but an increased consumption frequency of diet soft drinks (from 1·2 to 1·6 times/week, P < 0·001), were observed. From 2001 to 2008, boys increased their frequency of juice consumption (from 3·1 to 3·3 times/week) whereas girls decreased their frequency of juice consumption (3·8 to 3·4 times/week; interaction time × gender P = 0·02). Children with higher educated parents increased their frequency of juice consumption (3·6 to 3·8 times/week) whereas those with lower educated parents decreased their frequency of juice consumption (3·3 to 3·0 times/week; interaction time × parental education P = 0·04).

A lower frequency of consumption of sugar-sweetened beverages was observed among pupils in 2008 than in 2001. This is in accordance with the Norwegian health authority's goals and strategies for this time period, and is an important step to improve the dietary health of adolescents.