An age-period-cohort analysis of cannabis use prevalence and frequency in Germany, 1990-2009

Trends and projection in the proportion of (heavy) cannabis use in Germany from 1995 to 2021

AIMS

To measure the current trends of cannabis use in Germany, measure trends in the proportion of heavy cannabis users and estimate future cannabis use rates.

DESIGN

Repeated waves of the Epidemiological Survey on Substance Abuse, a cross-sectional survey conducted between 1995 and 2021 with a two-stage participant selection strategy where respondents completed a survey on substance use delivered through the post, over the telephone or on-line.

SETTING

Germany.

PARTICIPANTS/CASES

German-speaking participants aged between 18 and 59 years living in Germany who self-reported on their cannabis use in the past 12 months (n = 78 678). With the application of a weighting scheme, the data are nationally representative.

MEASUREMENTS

Questions on the frequency of cannabis use in the past 12 months and self-reported changes in frequency of use due to the COVID-19 pandemic.

FINDINGS

The prevalence of past 12-month cannabis users increased from 4.4% [95% confidence interval (CI) = 3.7, 5.1] in 1995 to 10.0% (95% CI = 8.9, 11.3) in 2021. Modeling these trends revealed a significant increase that accelerated over the past decade. The proportion of heavy cannabis users [cannabis use (almost) daily or at least 200 times per year] among past-year users has remained steady from 1995 (11.4%, 95% CI = 7.7, 16.5) to 2018 (9.5%, 95% CI = 7.6, 11.9), but significantly increased to 15.7% (95% CI = 13.1, 18.8) in 2021 during the COVID-19 pandemic. Extrapolating from these models, the prevalence of 12-month cannabis users in 2024 is expected to range between 10.4 and 15.0%, while the proportion of heavy cannabis users is unclear.

CONCLUSIONS

Trends from 1995 to 2021 suggest that the prevalence of past 12-month cannabis users in Germany will continue to increase, with expected rates between 10.4 and 15.0% for the German-speaking adult population, and that at least one in 10 cannabis users will continue to use cannabis heavily (almost daily or 200 + times in the past year).

The changing relationship between health risk behaviors and depression among birth cohorts of Canadians 65+, 1994-2014

BACKGROUND AND OBJECTIVE

The older adult residents of Canada form an increasingly larger proportion of the population and are becoming better educated and have more income. Depression is a common mental disorder, particularly among seniors. Several health risk behaviors-physical inactivity, tobacco use, and alcohol consumption-are linked to mental health problems. This study examines whether these health risk behaviors and their association with depression among Canadians 65+ born in eight cohorts between 1910-1914 and 1945-1949, have changed.

METHODS

Pooled data drawn from 11 nationally representative health surveys conducted by Statistics Canada between 1994 and 2014 are analyzed-88,675 survey participants met inclusion criteria. Depression was assessed by the Composite International Diagnostic Interview-Short Form. Health risk behaviors examined were physical activity/inactivity, smoking, and alcohol use. A Cochran Armitage trend test for categorical outcomes and a log-binomial modeling for binary outcomes were used to estimate the risk ratios across cohorts.

RESULTS

The proportions of Canadians 65+ who are physically active, regular drinkers, and regular smokers have increased; however, depression prevalence fluctuated non-significantly. Depression increased among all health risk behaviors, particularly in recent birth cohorts. Depression among physically inactive seniors, current smokers, and non-drinkers was significantly higher than among active, non-smokers, and regular drinkers (all P < 0.05). Physical inactivity and smoking-attributable depression risk showed an increasing linear trend across birth cohorts (RR = 1.67, P < 0.001; RR = 1.79, P < 0.001). For seniors born between 1915 and 1944, regular drinking was associated with a significant decrease in depression (all P < 0.001), but the protective effects of regular drinking became non-existent in the most recent 1945-1949 birth cohort (RR = 1.09, P < 0.05, after adjusting for covariates).

CONCLUSION

Inactivity and smoking were consistently associated with a significantly increased risk of depression among Canadian residents 65+, with smoking becoming more firmly connected to depression risk in more recent birth cohorts. In contrast, moderate alcohol use was associated with a decreased risk of depression, but that protective effect ceased in most recent birth cohort. Identifying the changing relationships between health risk behaviors and depression is meaningful for developing prevention strategies for depression and other emotional and mental health problems.

Trends in cannabis use and attitudes toward legalization and use among Australians from 2001-2016: an age-period-cohort analysis

BACKGROUND AND AIMS

Changes in cannabis legalization and availability in Australia necessitate monitoring use and attitudes. We estimated age-period-cohort effects of past-year cannabis use and attitudes toward criminalization and legalization.

DESIGN

Analysis of six waves of the Australian National Drug Strategy Household Survey (NDSHS) every 3 years (2001-2016).

SETTING AND PARTICIPANTS

The study was nationally representative of Australian households using multistage random sampling, totaling 145 168 respondents 18-79 years old. Data were collected using telephone, face-to-face, and drop-and-collect. Sample sizes per analysis varied based on data availability (~107 000-127 000 per model).

MEASUREMENTS

Six waves of data for past-year cannabis use (by sex and education), attitudes toward criminalization and legalization.

FINDINGS

Past-year cannabis use decreased in young adults ages 18-35 from 2001-2016 (25.1%-18.6%) and increased in middle adults ages 36-55 (8.6%-10.1%) and older adults ages 56-79 (0.6%-3.0%). We observed a positive period effect and negative cohort effect for recent cohorts for past-year use (e.g. 1955 cohort had 1.41 (95% CI: [1.11, 1.70]) increased log odds vs. 1998 cohort had -2.86 (95% CI: [-3.17, -2.55]) increased log odds) compared with the mean across years. Results were consistent by sex and varied by education. We observed a negative period effect for criminalization favorability (0.14 (95% CI: [0.003, 0.28]) increased log odds in 2001 vs. -0.31 (95% CI: [-0.45, -0.17]) increased log odds in 2016) and positive cohort effect for recent cohorts. Last, we observed a positive period effect for legalization support (-0.03 (95% CI: [-0.20, 0.14]) increased log odds in 2001 vs. 0.38 (95% CI: [0.22, 0.55]) increased log odds in 2016) and negative cohort effect for recent cohorts.

CONCLUSION

Cannabis use appears to be increasing in Australia among adults over 35, while decreasing among adolescents and young adults. Legalization support also appears to have been increasing since 2007, signaling discordance between use and attitudes among adolescents and young adults, and potentially predicting increases in use over time.

Past Year Cannabis Use Among Norwegian Adolescents: Time Trends Based on the Ungdata Surveys 2010-2019

Aims: To describe trends in cannabis use from 2010 to 2019 among Norwegian adolescents and relate these to individual- and municipal-level variables. Design: Data from nationwide repeated cross-sectional surveys collected in 2010-2013 (T1), 2014-2016 (T2), and 2017-2019 (T3) were used to describe secular trends in proportions of adolescent cannabis use. Setting: Cross-sectional surveys in 410 of the total 428 municipalities of Norway. Participants: A total of 628,678 survey responses from adolescents aged ~13-19 years of age, in which 566,912 survey responses were eligible for analyses, representing data from 340 municipalities. Measurements: Respondent's past year cannabis use, time, gender, school grade, municipality, geographical location, and municipality population. Findings: Boys reported overall higher cannabis use, with ~2:1 gender ratio for any past year cannabis use and a 3:1 gender ratio for frequent cannabis use. Adolescents in Eastern Norway reported higher cannabis use compared with other areas in the country, and adolescents from municipalities with a higher population size reported higher rates of cannabis use than smaller municipalities. A gradual increase in cannabis use from T1 to T3 was found in Eastern Norway and in the largest municipalities. More generally, proportions of past year cannabis use showed a marked increase from T2 to T3 across genders, grade/age groups, geographical location, and municipality population, with few exceptions. Conclusions: Our findings indicate that proportions of past year cannabis use have increased among Norwegian adolescents in recent years. Preventive interventions to hinder initiation of cannabis use, as well as measures to address frequent cannabis use among Norwegian adolescents, are needed.

Cross-classified multilevel models (CCMM) in health research: A systematic review of published empirical studies and recommendations for best practices

Recognizing that health outcomes are influenced by and occur within multiple social and physical contexts, researchers have used multilevel modeling techniques for decades to analyze hierarchical or nested data. Cross-Classified Multilevel Models (CCMM) are a statistical technique proposed in the 1990s that extend standard multilevel modeling and enable the simultaneous analysis of non-nested multilevel data. Though use of CCMM in empirical health studies has become increasingly popular, there has not yet been a review summarizing how CCMM are used in the health literature. To address this gap, we performed a scoping review of empirical health studies using CCMM to: (a) evaluate the extent to which this statistical approach has been adopted; (b) assess the rationale and procedures for using CCMM; and (c) provide concrete recommendations for the future use of CCMM. We identified 118 CCMM papers published in English-language literature between 1994 and 2018. Our results reveal a steady growth in empirical health studies using CCMM to address a wide variety of health outcomes in clustered non-hierarchical data. Health researchers use CCMM primarily for five reasons: (1) to statistically account for non-independence in clustered data structures; out of substantive interest in the variance explained by (2) concurrent contexts, (3) contexts over time, and (4) age-period-cohort effects; and (5) to apply CCMM alongside other techniques within a joint model. We conclude by proposing a set of recommendations for use of CCMM with the aim of improved clarity and standardization of reporting in future research using this statistical approach.

Trends in marijuana use in two Latin American countries: an age, period and cohort study

BACKGROUND AND AIMS

Uruguay and Chile have the highest levels of marijuana use in Latin America, and have experienced consistent increases during the last two decades. We aim to calculate separate age-period-cohort (APC) effects for past-year marijuana use in Uruguay and Chile, which have similar epidemiologica, and demographic profiles but diverging paths in cannabis regulation.

DESIGN

APC study in which period and cohort effects were estimated as first derivative deviations from their linear age trend, separately by country and gender.

SETTING

Uruguay and Chile.

PARTICIPANTS

General population between 15 and 64 years.

MEASUREMENTS

Past-year marijuana use from household surveys with five repeated cross-sections between 2001 and 2018 in Uruguay (median n = 4616) and 13 between 1994 and 2018 in Chile (median n = 15 895).

FINDINGS

Marijuana use prevalence in both countries peaked at 20-24 years of age and increased consistently across calendar years. Period effects were strong and positive, indicating that increases in use were evident across age groups. Relative to 2006 (reference year), Chilean period effects were approximately 48% lower in 1994 and approximately four times higher in 2018; in Uruguay, these effects were approximately 56% lower in 2001 and almost quadrupled in 2018. We observed non-linear cohort effects in Chile and similar patterns in Uruguay for the overall sample and women. In both countries, marijuana use increased for cohorts born between the mid-1970s and early 1990s, even in the context of rising period effects. Prevalence was consistently larger for men, but period increases were stronger in women.

CONCLUSIONS

Age-period-cohort effects on past-year marijuana use appear to have been similar in Chile and Uruguay, decreasing with age and increasing over time at heterogeneous growth rates depending on gender and cohort. Current levels of marijuana use, including age and gender disparities, seem to be associated with recent common historical events in these two countries.

Illicit drug use by mothers and their daughters in Australia: A comparison of two generations

BACKGROUND

While recent decades have witnessed an increase in the use of illicit drugs in Australia, the extent to which the types of drugs used has changed over a generation of young women has not been documented.

METHODS

Data are from a prospective birth cohort study. Mothers were recruited in early pregnancy (1981-83) and then they and their child were followed up, with mothers interviewed 27 years (2008-2011), and daughters 30 years (2010-14), after the birth. At these most recent interviews both mothers and daughters were administered the Composite International Diagnostic Interview (CIDI III). Comparisons are for mothers and daughters separated by a 25 year period. For this study, we compare levels of lifetime use of a range of illicit drugs and drug use disorders reported by mothers and their daughters (N = 998 mother/daughter pairs) with adjustment for family income, marital status, education and occupation.

RESULTS

There has been a generational increase in the use of illicit substances and prevalence of substance use disorders experienced by Australian women. Mothers' use of illicit drugs was generally restricted to cannabis. By contrast the majority of daughters report lifetime use of an illicit drug with cannabis, club drugs and stimulants the most common. Compared to the mothers, daughters used club drugs 50 times, cocaine 19 times and inhalants 20 times more often. Daughters report experiencing 12 times the rate of cocaine use disorders, 9 times the rate of stimulant disorders and 7 times the rate of cannabis use disorders compared to their mothers.

CONCLUSIONS

Mothers of the current generation of 30 year old Australian women rarely used illicit drugs and few experienced a drug use disorder. The current generation of young women report commonly using one or more illicit drugs with a substantial minority experiencing a drug use disorder. It is unlikely that the use of illicit drugs by young women in Australia will be reversed in the foreseeable future. Government policies and treatment practices need to be calibrated to the reality of the much greater contact with illicit drugs being exhibited by younger women.

Past-month cannabis use among U.S. individuals from 2002-2015: An age-period-cohort analysis

BACKGROUND

Cannabis is the most commonly used illicit drug among U.S. adolescents and adults, but little is known about factors that drive trends in cannabis use prevalence. To better understand drivers of these trends, we aimed to estimate age, period, and cohort effects on past-month cannabis use among U.S. individuals age 12 and older from 2002 to 2015.

METHODS

We conducted an age-period-cohort analysis on past-month cannabis use among participants ages 12 and older using the National Survey on Drug Use and Health (NSDUH), an annual cross-sectional nationally-representative survey of drug use. Additionally, we examined how age, period, and cohort effects differed across gender. Participants (n = 779,799) self-reported cannabis patterns using a computer-assisted telephone interview (CATI).

RESULTS

Past-month cannabis use in this population increased from 6.0% in 2002 to 8.1% in 2015. Distinct age, period, and cohort effects were observed. Compared to participants ages 12-13, participants ages 18-21 (PR: 16.8, 95% CI: 15.6, 18.1) and 22-25 (PR: 13.2, 95% CI: 12.2, 14.4) had dramatically higher prevalence of past-month cannabis use. Compared to participants in 2002, participants in 2014 (PR: 1.2, 95% CI: 1.1, 1.4) and 2014 (PR: 1.2, 95% CI: 1.1, 1.4) had slightly higher prevalence of past-month cannabis use. Compared to the 1940s birth cohort, the 1950s birth cohort (PR: 1.8, 95% CI: 1.5, 2.2) had a higher prevalence of past-month cannabis use.

CONCLUSIONS

Past-month cannabis use is prevalent and increasing among U.S. adults. Distinct age, period, and cohort effects are at play, though age effects are strongest.

Evidence for Sex Convergence in Prevalence of Cannabis Use: A Systematic Review and Meta-Regression

OBJECTIVE

Generally, cannabis use has been more prevalent in men than in women. However, emerging evidence suggests that the prevalence of cannabis use is converging among males and females from recent cohorts. This study aimed to systematically summarize published literature on birth cohort changes in male-to-female ratios in prevalence of cannabis use.

METHOD

Twenty-two studies with a median sample size of 85,052 were identified for inclusion. Data were collected between 1979 and 2010, representing birth cohorts from 1936 to 1999. For quantitative synthesis, male-to-female ratios in prevalence of any cannabis use were calculated for all 5-year birth cohorts available, generating 348 separate ratios among birth cohorts from 1941 to 1995 in 30 countries. Random-effects meta-analyses generated pooled sex ratios, stratified by 5-year birth cohorts.

RESULTS

Of the 22 included studies, 10 reported some evidence of sex convergence in cannabis use among more recent cohorts. Quantitative synthesis found that the ratio of cannabis use prevalence in males and females decreased significantly from 2.0 among cohorts born in 1941 to 1.3 among those born in 1995.

CONCLUSIONS

Findings support the narrowing sex gap in the prevalence of cannabis use. Results are concordant with a broader literature demonstrating sex convergence in prevalence of other substance use, particularly alcohol use and related harms. Both young women and men should be the target of prevention and early intervention efforts. Future research in more diverse global settings, especially in low- and middle-income countries, would enhance the international scope of the findings.

Upper gastrointestinal cancer burden in Hebei Province, China: A population-based study

AIM

To investigate the incidence and mortality rates of upper gastrointestinal cancer (UGIC) in Hebei Province, China, and to identify high-risk populations to improve UGIC prevention and control.

METHODS

Data for UGIC patients were collected from 21 population-based cancer registries covering 15.25% of the population in Hebei Province. Mortality data were extracted from three national retrospective death surveys (1973-1975, 1990-1992 and 2004-2005). The data were stratified by 5-year age groups, gender and area (high-risk/non-high-risk areas) for analysis. The age-period-cohort and grey system model were used.

RESULTS

The crude incidence rate of UGIC was 55.47/100000, and the adjusted rate (Segi’s population) was 44.90/100000. Males in rural areas had the highest incidence rate (world age-standardized rate = 87.89/100000). The crude mortality rate of UGIC displayed a decreasing trend in Hebei Province from the 1970s to 2013, and the adjusted rate decreased by 43.81% from the 1970s (58.07/100000) to 2013 (32.63/100000). The mortality rate declined more significantly in the high-risk areas (57.26%) than in the non-high-risk areas (55.02%) from the 1970s to 2013. The median age at diagnosis of UGIC was 65.06 years in 2013. There was a notable delay in the median age at death from the 1970s (66.15 years) to 2013 (70.39 years), especially in the high-risk areas. In Cixian, the total trend of the cohort effect declined, and people aged 65-69 years were a population at relatively high risk for UGIC. We predicted that the crude mortality rates of UGIC in Cixian and Shexian would decrease to 98.80 and 133.99 per 100000 in 2018, respectively.

CONCLUSION

UGIC was the major cause of cancer death in Hebei Province, and males in rural areas were a high-risk population. We should strengthen early detection and treatment of UGIC in this population.

From cannabis initiation to daily use: educational inequalities in consumption behaviours over three generations in France

AIMS

The diffusion of cannabis initiation has been accompanied by a reversal in the educational gradient: contrary to older generations, the less educated in recent generations are more likely to initiate than the more educated. We tested whether the educational gradient for the transition from initiation to daily use evolved in the same way.

DESIGN/SETTING

A French telephone random survey conducted in 2010 (21 818 respondents aged 15-64 years), asking interviewees about their ages at initiation to daily use, if any.

PARTICIPANTS

A total of 6824 cannabis initiators aged 18-64 years at data collection. Three birth cohort groups (generations) were compared: 1946-60 (n = 767), 1961-75 (n = 2632) and 1976-92 (n = 3425) with, respectively, 47, 42 and 45% of women.

MEASURES

Risks of transition to daily use from ages 11-34 were compared through time-discrete logistic regressions and educational gradients were quantified through a relative index of inequality (RII). Control variables include age and time-varying variables (ages at tobacco daily use, at first drunkenness and at first other use of an illicit drug in a list of 13 products).

FINDINGS

Twenty-four per cent of the initiators reported daily use before age 35, the proportions tripling from the oldest to the youngest generation (from 11.7 to 38.6% in men, from 7.7 to 22.2% in women). Whatever the generation, the less educated initiators more often shifted to daily use than the most educated: from the oldest to the youngest generation, RII = 2.13, 95% confidence interval (CI) = [0.65, 7.02]; 2.19 95% CI = [1.33, 3.63]; and 2.24, 95% CI = [1.60, 3.15] in men; RII = 3.31, 95% CI = [0.75, 14.68]; 3.17, 95% CI = [1.49, 6.76]; and 3.56, 95% CI = [2.07, 6.14] in women, respectively.

CONCLUSION

In France, the risk of transition from cannabis initiation to daily use has remained consistently higher among less educated cannabis initiators over three generations (1946-60, 1961-75, 1976-92), in contrast to what is observed for initiation.

Morbidity and suicide mortality following sick leave in relation to changes of social insurance regulations in Sweden

BACKGROUNDS

Stricter regulations including time limits for sick leave have been introduced in Sweden in 2008, which might have resulted in higher morbidity in those on longer sick-leave spells after the introduction. This study aimed to examine (i) the association between all-cause and diagnosis-specific sickness absence and sick-leave duration with subsequent morbidity and suicide mortality and (ii) differences in socio-demographics and morbidity in individuals on sickness absence regarding changes of social insurance regulations.

METHODS

A population-based prospective study was conducted of two cohorts of individuals who lived in Sweden, aged between 20 and 64 years at 31 December 2005 (n = 4 477 678) and at 31 December 2008 (n = 4 500 400), respectively. Each of the cohorts was followed regarding inpatient healthcare and suicide. Hazard ratios (HR) and 95% confidence intervals were estimated by Cox regression models.

RESULTS

In the multivariate analyses, all-cause and diagnosis-specific sickness absence and sick-leave duration showed higher HRs for inpatient care and suicide in both cohorts (range of HR:1.10-2.59). HRs of inpatient care and suicide among individuals with mental sickness absence 2009 were reduced more after controlling for morbidity-related covariates, than such sickness absence in 2006. Individuals with mental and somatic sickness absence and sickness absence > 180 days in 2009 had higher HRs of somatic inpatient care than those on sickness absence in 2006.

CONCLUSIONS

Diagnosis-specific sickness absence and long-term sickness absence in 2009 might be associated with more severe morbidity or work incapacity than in 2006 due to the stricter regulations.

Time Trends of Cannabis Use Among Treatment-seeking Individuals at Government De-addiction Centers Across India Over a Period of 7 Years

BACKGROUND

Cannabis continues to be the most commonly used illicit psychoactive substance globally. The National Survey in India conducted in the year 2004 also reported it to be the most commonly used illicit substance in the country. Furthermore, it was reported to be the second most commonly used psychoactive substance by the treatment seekers at de-addiction centers in the country.

OBJECTIVES

To assess time trends of cannabis use among treatment-seeking individuals at government de-addiction centers across India over a period of 7 years.

MATERIALS AND METHODS

The study utilized data collected through Drug Abuse Monitoring System across India. The data of treatment seekers from de-addiction centers established under the Drug De-addiction Program, Ministry of Health and Family Welfare, Government of India and supported by the Ministry of Social Justice and Empowerment, Government of India (122 in number) across the country were analyzed.

RESULTS

A total of 107,469 individuals sought treatment from government de-addiction centers over the 7 years (2007-2013) period. With the exception of an aberration for the year 2012, there has been a steady decline in the proportion of treatment seekers who are not current cannabis users. A significantly greater proportion (Chi-square: 586.30, df: 1, P < 0.001) of individuals with current cannabis use alone or along with tobacco (20.4%) tend to have a co-morbid psychiatric disorder as compared to treatment seekers with current use of substances other than cannabis (6.1%).

CONCLUSIONS

It is important to focus on cannabis in clinical service delivery and research in the country.

Changing relationships between smoking and psychiatric disorders across twentieth century birth cohorts: clinical and research implications

As the risks of tobacco use become recognized and smoking becomes stigmatized, new smokers may be increasingly driven to smoke by biological or genetic vulnerabilities rather than social desirability. Given that genetic risk for deviant proneness is shared across other psychiatric and addictive disorders, we predicted that as rates of smoking decreased through the latter half of the twentieth century, associations between smoking and psychopathology would increase. Participants (N=25 412) from a large US study-the National Epidemiologic Survey on Alcohol and Related Conditions, NESARC-were interviewed using the Alcohol Use Disorder and Associated Disabilities Interview Schedule - DSM-IV Version (AUDADIS-IV) and classified into one of five birth cohort decades (1940s to 1980s) and three smoking history (nonsmokers, never-dependent smokers and ever-dependent smokers) groups. We found that the prevalence of smoking decreased across the five birth cohorts, but associations of smoking with drug and AUDs, attention-deficit hyperactivity disorder, bipolar disorder and antisocial personality disorder, each increased monotonically in more recently born cohorts, even after adjusting for concurrent demographic and socioeconomic changes. For drug and AUDs, increases were observed among smokers both with and without a history of nicotine dependence; for other outcomes, increases were entirely driven by nicotine-dependent smokers. Findings suggest that smokers in more recent cohorts have disproportionately high psychiatric vulnerability, and may benefit from greater mental health screenings. Differentiating between casual and dependent smokers may further help prioritize those at greatest risk. Researchers should also be aware of potential variation in psychiatric comorbidity based on cohort of birth when defining groups of smokers, to minimize confounding.

Comments on Hynes et al. Prevalence of Marijuana Use among University Students in Bolivia, Colombia, Ecuador and Peru. Int. J. Environ. Res. Public Health 2015, 12, 5233-5240

We have read and analyzed the article entitled "Prevalence of marijuana use among university students in Bolivia, Colombia, Ecuador and Peru". We propose some objective points which could enhance the internal validity of the study (i.e., we suggest to report participation proportions).

Age, period and cohort trends in drug abuse hospitalizations within the total Swedish population (1975-2010)

BACKGROUND

The societal consequences of drug abuse (DA) are severe and well documented, the World Health Organization recommending tracking of population trends for effective policy responses in treatment of DA and delivery of health care services. However, to correctly identify possible sources of DA change, one must first disentangle three different time-related influences on the need for treatment due to DA: age effects, period effects and cohort effects.

METHODS

We constructed our main Swedish national DA database (spanning four decades) by linking healthcare data from the Swedish Hospital Discharge Register to individuals, which included hospitalisations in Sweden for 1975-2010. All hospitalized DA cases were identified by ICD codes. Our Swedish national sample consisted of 3078,129 men and 2921,816 women. We employed a cross-classified multilevel logistic regression model to disentangle any net age, period and cohort effects on DA hospitalization rates.

RESULTS

We found distinct net age, period and cohort effects, each influencing the predicted probability of hospitalisation for DA in men and women. Peak age for DA in both sexes was 33-35 years; net period effects showed an increase in hospitalisation for DA from 1996 to 2001; and in birth cohorts 1968-1974, we saw a considerable reduction (around 75%) in predicted probability of hospitalisation for DA.

CONCLUSIONS

The use of hospital admissions could be regarded as a proxy of the population's health service use for DA. Our results may thus constitute a basis for effective prevention planning, treatment and other appropriate policy responses.

Trends im Substanzkonsum Jugendlicher: Gibt es regionale Unterschiede?

Fragestellung: Es wurde untersucht, ob auf Bundeslandebene Unterschiede im Alkohol-, Tabak- und Cannabiskonsum Jugendlicher und seiner Zeitverläufe bestehen. Methodik: Daten von 23.997 Jugendlichen aus drei Erhebungswellen (2003; 2007; 2011) der Europäischen Schülerstudie zu Alkohol und anderen Drogen (ESPAD) der 9. und 10. Klasse aus fünf Bundesländern (Bayern, Berlin, Brandenburg, Mecklenburg-Vorpommern, Thüringen) wurden deskriptiv und regressionsanalytisch ausgewertet. Ergebnisse: Länderübergreifend zeigen sich für alle drei Substanzen sinkende Konsumwerte über die Zeit. Für den Cannabiskonsum ist dieser Trend nur bis 2007 zu beobachten. Berlin weist den geringsten Alkohol- und höchsten Cannabiskonsum auf. Der Tabakkonsum ist in Brandenburg und Mecklenburg-Vorpommern am höchsten und zeigt den stärksten Rückgang in Thüringen. Schlussfolgerungen: Trotz einiger Unterschiede in den Konsumprofilen der Bundesländer sind die Trends sehr homogen. Insgesamt betrachtet sind die beobachteten Konsumparameter, die sich im europäischen Vergleich auf hohem bis mittlerem Niveau befinden, rückläufig.

Smoking and psychopathology increasingly associated in recent birth cohorts

BACKGROUND

In recent decades, smoking has become an increasingly non-normative behavior. Because deviant behaviors are associated with greater clinical and genetic risks, current-generation smokers may have greater concentrations of psychiatric comorbidity than previous generations. We examined this question empirically by testing whether associations between measures of smoking, psychiatric diagnoses, and risk-associated personality traits, increased across seven birth-cohorts of the 20th century.

METHOD

4326 subjects from a cross-sectional NIMH control sample were categorized into one of seven groups based on birth (born before 1930, and 1930s-80s) and one of three smoking levels (lifetime dependent smoker, never dependent smoker, never smoker). Smoking and ND were assessed using the Fagerstrom Test for Nicotine Dependence; psychiatric diagnoses (drug and alcohol dependence, major depression, and generalized anxiety disorder) using the Composite International Diagnostic Interview-Short Form, and personality traits (neuroticism and extraversion) with the Eysenck Personality Questionnaire.

RESULT

Lifetime prevalence of smoking decreased across the seven cohorts. Associations between smoking and drug dependence, generalized anxiety, and neuroticism, as well as total psychiatric comorbidity, were greater in more recent cohorts [smoking-by-cohort interaction: p<0.01], with greatest increases contributed by nicotine-dependent smokers. Smoking was also independently associated with alcohol dependence and depression, but these associations did not significantly vary across cohorts.

CONCLUSIONS

More recent generations included fewer persons who smoked, but their smoking was associated with greater psychiatric morbidity. Failure to account for systematic variation in comorbidity across smoking cohorts may lead to unwanted heterogeneity in clinical, and possibly genetic, studies of nicotine dependence.

Changes in cannabis use among young people: impact on mental health

PURPOSE OF REVIEW

The aim of this review was to examine current trends in cannabis use and cannabis use disorder (CUD) among youth, and to investigate recent findings concerning the relationship between cannabis use and mental health concerns, with a focus on how use during adolescence may interact with related mental health disorders.

RECENT FINDINGS

Current data indicate that cannabis use among adolescents has shown both marginal increases and decreases, depending on global location; however, the profile of cannabinoids in cannabis may now be biased toward those that promote psychotogenic and memory-impairing effects. CUD has been found most prevalent among youth. After controlling for multiple confounders, longitudinal research suggests that cannabis use predicts the development of anxiety disorders, depression, suicidal ideation, certain personality disorders, and interpersonal violence. Further, associations have been found stronger in adolescents relative to adults, and younger age of initiation increases the risk of developing mental health disorders.

SUMMARY

Cannabis use among youth remains prevalent, and recent studies are consolidating previous findings that adolescents are especially vulnerable to mental health disorders associated with cannabis. This suggests that cannabis involvement requires increased prominence in research, prevention initiatives, routine screening, and interventions to improve adolescent mental health.

Substanzkonsum und substanzbezogene Störungen: Trends in Deutschland 1980 – 2012

Ziel: Untersucht wurden geschlechts- und altersspezifische Trends des Konsums von Alkohol, Tabak und Cannabis und der Einnahme von Schmerz-, Schlaf- und Beruhigungsmitteln sowie Trends substanzbezogener Störungen nach DSM-IV im Zeitraum 1980 bis 2012. Methodik: Grundlage sind Daten aus zehn Erhebungen des Epidemiologischen Suchtsurveys (ESA). Die Datenerhebung erfolgte schriftlich bzw. im Methodenmix. Die Antwortraten variierten zwischen 45 % und 65 %. Ergebnisse: Die durchschnittlich pro Tag konsumierte Menge Reinalkohol reduzierte sich bei Männern signifikant gegenüber dem Jahr 1995, während der Konsum unter Frauen auf niedrigerem Niveau stabil blieb. Die Anteile der aktuellen Raucher zeigen bei beiden Geschlechtern mit wenigen Ausnahmen einen klaren rückläufigen Trend. Die 12-Monats-Prävalenz des Cannabiskonsums war im Jahr 2012  höher als im Jahr 1995. Die regelmäßige Einnahme von Schmerzmitteln zeigt mit wenigen Ausnahmen eine Zunahme über die Zeit. Es wurden Anstiege in der Prävalenz der Abhängigkeit von Alkohol (1997 bis 2012), Tabak (2000 bis 2012) und Beruhigungsmitteln (2000 bis 2012) beobachtet. Schlussfolgerungen: Der Konsum legaler Substanzen ist in Deutschland insgesamt rückläufig. Mehr Anstrengungen sind nötig, um den Konsum von Cannabis und Schmerzmitteln sowie substanzbezogene Störungen auf Bevölkerungsebene zu reduzieren.