Late-onset Users Research Articles

Mobile Phone Addiction as an Emerging Behavioral Form of Addiction Among Adolescents in India

Introduction: The advancements in mobile phones from simple basic phones to featured phones and smartphones resulted in the penetration of technology to different groups of people irrespective of age, gender, or region. Thus, mobile phone addiction has evolved as a form of behavioral addiction found to be increasingly prevalent among adolescents too. The study aimed to determine the prevalence of mobile phone addiction among adolescents and its associated risk factors among adolescents.Method and results: A community-based, cross-sectional study was conducted among 264 adolescents (10-19 years) of low-income urban areas of Delhi. The prevalence of mobile phone addiction in the participants was 33.0% (95% CI: 27.2-38.6). The addiction was higher among boys (33.6%) than girls (32.3%) (p=0.835). Mobile phone addiction was found to be significantly higher among those adolescents who had ≥3 siblings, those belonging to nuclear families, and among late-onset users (≥16 years). Late-onset users (adjusted odds ratio {aOR}: 3.398; 95% CI: 1.307-8.833) and ≥3 siblings (aOR: 1.980; 95% CI: 1.141-3.437) were independent predictors of mobile phone addiction. The mean time spent on mobile phones was significantly higher among those with addiction but no significant gender difference was found between time spent on phones and addiction.Conclusion: The high prevalence of mobile phone addiction found in our study is an indication of the potential public health concern posed by mobile phone use among adolescents in urban settings. Hence, it is essential to limit the access to mobile phones for important utility purposes for adolescents.

LIFESPAN CANNABIS USE PATTERNS IN OLDER USERS

The rapidly rising rates of cannabis use among older adults may reflect a rise in late-onset users, re-engagement after a period without use, or a continuous use pattern since young adulthood that is more visible after legalization of cannabis. Older (age 60+) cannabis users (n=82) provided retrospective ratings on their frequency of use across adulthood. Approximately 28% were not using cannabis when young adults, with a larger percentage (40%) reporting non-use while ages 31-49 and 37% reported non-use when ages 50-64. Approximately 21% of older users were first time users, with 60% low frequency and 35% daily/weekly users. High frequency users generally were high frequency users throughout adulthood, but the pattern varied substantially by gender and mode of consumption. Women were more likely first-time users than men, and more likely non-smokers. Among non-smokers, about 40% were first-time users. Implications are explored for research, policy, and clinical practice.

Distinct cognitive performance and patterns of drug use among early and late onset cocaine users

IntroductionAdolescence is a crucial period for neurodevelopment, but few studies have investigated the impact of early cocaine use on cognitive performance and patterns of substance use. MethodsWe evaluated 103 cocaine dependent inpatients divided in two groups: early-onset users (EOG; n=52), late-onset users (LOG; n=51), and 63 healthy controls. Neuropsychological functioning was evaluated using Digits Forward (DF) and Backward (DB), Trail Making Test (TMT), Stroop Color Word Test (SCWT), Controlled Oral Word Association Test (COWAT), Wisconsin Card Sorting Test (WCST), Rey Osterrieth Complex Figure Test (ROCFT), Frontal Assessment Battery (FAB), and Iowa Gambling Test (IGT). Use of alcohol and other drugs was assessed with the Addiction Severity Index (ASI-6). ResultsAnalyses of covariance controlling for age, IQ and years of education showed that EOG presented worse performance in attention span (DF, p=0.020), working memory (DB, p=0.001), sustained attention (WCST, p=0.030), declarative memory (ROCFT, p=0.031) and general executive functioning (FAB, p=0.003) when compared with the control group. LOG presented impairments on divided attention (TMT, p=0.003) and general executive functioning (FAB, p=0.001) in relation to the control group. EOG presented higher use of cannabis and alcohol than LOG (p≤0.001). ConclusionEarly-onset cocaine users display more pronounced neuropsychological alterations than controls, as well as a greater frequency of polydrug consumption than LOG. The prominent cognitive deficits in EOG probably reflect the deleterious interference of cocaine use with early stages of neurodevelopment. This may be related to more severe clinical characteristics of substance disorder in this subgroup, including polysubstance abuse.

Cognitive Function in Individuals With Psychosis: Moderation by Adolescent Cannabis Use.

Prior cannabis use, compared to nonuse, is reported to be associated with less cognitive impairment in schizophrenia. The age of cannabis use and the persistent influence of cannabis use on cognitive function has not been examined across the psychosis dimension. Ninety-seven volunteers with psychosis (schizophrenia, schizoaffective, or bipolar psychosis) and 64 controls were recruited at the Dallas site of the Bipolar-Schizophrenia Network on Intermediate Phenotypes consortium. Cannabis use history obtained in a semi-structured manner was used to categorize subjects into nonusers, adolescent-onset users, and late-onset users. The a priori hypothesis tested was that individuals with psychosis and a history of adolescent cannabis use (ACU) would have better global neuropsychological performance, as measured by the Brief Assessment of Cognition in Schizophrenia (BACS) battery, compared to those with psychosis and no cannabis use history. BACS Composite scores were significantly higher in individuals with psychosis with ACU compared to individuals with psychosis and no prior cannabis use. In subgroup analyses, ACU influenced global cognition in the schizophrenia/schizoaffective (SCZ) subgroup but not the bipolar psychosis subgroup. Exploratory analyses within the SCZ group, suggest that ACU was associated with better performance in specific domains compared to non-ACU groups. There are distinct associations between age of cannabis use and neuropsychological function across psychotic illnesses. Specifically, ACU is associated with better cognitive function in SCZ but not bipolar psychosis. This age-dependent and diagnosis-specific influence of cannabis may need to be factored into the design of future cognitive studies in SCZ.

Evaluating the relationship between cannabis use and IQ in youth and young adults at clinical high risk of psychosis

Among people with psychosis, those with a history of cannabis use show better cognitive performance than those who are cannabis naïve. It is unknown whether this pattern is present in youth at clinical high risk (CHR) of psychosis. We evaluated relationships between IQ and cannabis use while controlling for use of other substances known to impact cognition in 678 CHR and 263 healthy control (HC) participants. IQ was estimated using the Vocabulary and Block Design subtests of the Wechsler Abbreviated Scale of Intelligence. Drug and alcohol use severity and frequency were assessed with the Alcohol and Drug Use Scale, and we inquired participants' age at first use. CHR were further separated into early and late age at onset of cannabis use sub-groups, and low-, moderate- and high-frequency sub-groups. No significant differences in IQ emerged between CHR or HC cannabis users vs. non-users, or between use frequency groups. CHR late-onset users showed significantly higher IQ than CHR early-onset users. Age at onset of cannabis use was significantly and positively correlated with IQ in CHR only. Results suggest that age at onset of cannabis may be a more important factor for IQ than use current use or use frequency in CHR.

Preliminary findings demonstrating latent effects of early adolescent marijuana use onset on cortical architecture

BackgroundAs the most commonly used illicit substance during early adolescence, long-term or latent effects of early adolescent marijuana use across adolescent developmental processes remain to be determined. MethodsWe examined cortical thickness, gray/white matter border contrast (GWR) and local gyrification index (LGI) in 42 marijuana (MJ) users. Voxelwise regressions assessed early-onset (age <16) vs. late-onset (≥16 years-old) differences and relationships to continued use while controlling for current age and alcohol use. ResultsAlthough groups did not differ by onset status, groups diverged in their correlations between cannabis use and cortical architecture. Among early-onset users, continued years of MJ use and current MJ consumption were associated with thicker cortex, increased GWR and decreased LGI. Late-onset users exhibited the opposite pattern. This divergence was observed in all three morphological measures in the anterior dorsolateral frontal cortex (p<.05, FWE-corrected). ConclusionsDivergent patterns between current MJ use and elements of cortical architecture were associated with early MJ use onset. Considering brain development in early adolescence, findings are consistent with disruptions in pruning. However, divergence with continued use for many years thereafter suggests altered trajectories of brain maturation during late adolescence and beyond.

Cannabis use before age 15 and subsequent executive functioning

Many studies have suggested that adolescence is a period of particular vulnerability to neurocognitive effects associated with substance misuse. However, few large studies have measured differences in cognitive performance between chronic cannabis users who started in early adolescence (before age 15) with those who started later. To examine the executive functioning of individuals who started chronic cannabis use before age 15 compared with those who started chronic cannabis use after 15 and controls. We evaluated the performance of 104 chronic cannabis users (49 early-onset users and 55 late-onset users) and 44 controls who undertook neuropsychological tasks, with a focus on executive functioning. Comparisons involving neuropsychological measures were performed using generalised linear model analysis of variance (ANOVA). The early-onset group showed significantly poorer performance compared with the controls and the late-onset group on tasks assessing sustained attention, impulse control and executive functioning. Early-onset chronic cannabis users exhibited poorer cognitive performance than controls and late-onset users in executive functioning. Chronic cannabis use, when started before age 15, may have more deleterious effects on neurocognitive functioning.

Multiple Sclerosis, Cannabinoids, and Cognition

Multiple Sclerosis, Cannabinoids, and Cognition

Hypothalamic–pituitary–adrenal axis activity and early onset of cannabis use

To identify early onset cannabis users by measuring basal hypothalamic-pituitary-adrenal (HPA) axis activity, which may be a risk factor for early onset substance use when showing low activity. In a prospective cohort study, adolescents who initiated cannabis use at an early age (9-12 years), those who initiated at a later age (13-14 years) and those who did not use cannabis by the age of 14 were compared with respect to HPA axis activity. Data were used from the first and second assessment wave of the TRacking Adolescents' Individual Lives Survey (TRAILS), that included 1768 Dutch young adolescents aged 10-12 years who were followed-up across a period of 2 years. Cortisol was measured in saliva samples at awakening, 30 minutes later and at 8 p.m. at age 10-12. Self-reported age at first cannabis use was used. The early onset group had lower cortisol levels 30 minutes after awakening than the late onset group (OR = 0.93, 95% CI: 0.86-0.99). Furthermore, compared to non-users, the early and late onset cannabis users had higher levels of cortisol at 8 p.m. (OR = 1.25, 95% CI: 1.03-1.53 and OR = 1.21, 95% CI: 1.01-1.45, respectively). Some evidence was found for HPA axis hypo-activity at awakening in adolescents with early onset of cannabis use compared to late onset users, which might indicate an increased risk for early onset users of seeking stimulation to restore arousal levels by using substances.

Substance initiation sequences among Taiwanese adolescents using methamphetamine

The aim of this study was to examine substance initiation sequences in Taiwanese adolescent methamphetamine (MAMP) users. Three hundred adolescent MAMP users were questioned about their use of cigarettes, alcohol, areca quid, benzodiazepine, glue, marijuana, MAMP and heroin. The sequences of substance use before MAMP use were determined in every subject according to their age at substance initiation. The sequences of substance initiation were compared between genders and between early-onset and late-onset MAMP users. The results revealed that the adolescents had used cigarettes, alcohol and areca quid before MAMP, and very few (4%) adolescents had started using MAMP before using other substances. Female MAMP users were more likely to use MAMP as their first substance and were less likely to use areca quid than males. Male early-onset MAMP users were more likely to drink alcohol and chew areca quid before MAMP use than were late-onset users. This study found that the sequences of substance initiation were different between genders and between the early-onset and late-onset MAMP users. There are several findings that are different from those in Western studies on the sequence of substance initiation in the adolescent population.

Late-Onset Crack Users

This article explores late-onset crack use among midlife and older adults as an emerging risk factor for HIV infection. Most research on illicit drug use and HIV infection/AIDS has focused on younger drug users, typically those who inject. The initiation into crack use during later adulthood challenges this narrow view. The analysis the authors present was drawn from qualitative and quantitative data collected as part of their ongoing research on illicit drug use. The subsample consisted of 27 men who began using crack at the age of 50 or older and 40 women who started using crack at the age of 35 or older. The findings suggest a typology of late-onset users with differing forms of HIV risk and prevention needs. The authors end the article with recommendations for effective HIV risk reduction programs for late-onset crack users.

Early-onset cannabis use and cognitive deficits: what is the nature of the association?

Background: Individuals who initiate cannabis use at an early age, when the brain is still developing, might be more vulnerable to lasting neuropsychological deficits than individuals who begin use later in life. Methods: We analyzed neuropsychological test results from 122 long-term heavy cannabis users and 87 comparison subjects with minimal cannabis exposure, all of whom had undergone a 28-day period of abstinence from cannabis, monitored by daily or every-other-day observed urine samples. We compared early-onset cannabis users with late-onset users and with controls, using linear regression controlling for age, sex, ethnicity, and attributes of family of origin. Results: The 69 early-onset users (who began smoking before age 17) differed significantly from both the 53 late-onset users (who began smoking at age 17 or later) and from the 87 controls on several measures, most notably verbal IQ (VIQ). Few differences were found between late-onset users and controls on the test battery. However, when we adjusted for VIQ, virtually all differences between early-onset users and controls on test measures ceased to be significant. Conclusions: Early-onset cannabis users exhibit poorer cognitive performance than late-onset users or control subjects, especially in VIQ, but the cause of this difference cannot be determined from our data. The difference may reflect (1) innate differences between groups in cognitive ability, antedating first cannabis use; (2) an actual neurotoxic effect of cannabis on the developing brain; or (3) poorer learning of conventional cognitive skills by young cannabis users who have eschewed academics and diverged from the mainstream culture.

Specific attentional dysfunction in adults following early start of cannabis use

The present study tested the hypothesis that chronic interference by cannabis with endogenous cannabinoid systems during peripubertal development causes specific and persistent brain alterations in humans. As an index of cannabinoid action, visual scanning, along with other attentional functions, was chosen. Visual scanning undergoes a major maturation process around age 12-15 years and, in addition, the visual system is known to react specifically and sensitively to cannabinoids. From 250 individuals consuming cannabis regularly, 99 healthy pure cannabis users were selected. They were free of any other past or present drug abuse, or history of neuropsychiatric disease. After an interview, physical examination, analysis of routine laboratory parameters, plasma/urine analyses for drugs, and MMPI testing, users and respective controls were subjected to a computer-assisted attention test battery comprising visual scanning, alertness, divided attention, flexibility, and working memory. Of the potential predictors of test performance within the user group, including present age, age of onset of cannabis use, degree of acute intoxication (THC+THCOH plasma levels), and cumulative toxicity (estimated total life dose), an early age of onset turned out to be the only predictor, predicting impaired reaction times exclusively in visual scanning. Early-onset users (onset before age 16; n = 48) showed a significant impairment in reaction times in this function, whereas late-onset users (onset after age 16; n = 51) did not differ from controls (n = 49). These data suggest that beginning cannabis use during early adolescence may lead to enduring effects on specific attentional functions in adulthood. Apparently, vulnerable periods during brain development exist that are subject to persistent alterations by interfering exogenous cannabinoids.