Does regular cannabis use affect neuroanatomy? An updated systematic review and meta-analysis of structural neuroimaging studies

European Archives of Psychiatry and Clinical Neuroscience - Regular cannabis use is associated with adverse cognitive and mental health outcomes that have been ascribed to aberrant neuroanatomy in...     

Statin use and risk of Parkinson’s disease: a meta-analysis of observational studies

Inconsistent results regarding the association between statin use and risk of Parkinson’s disease (PD) have been reported. We therefore examined the association between statin use and risk of PD by conducting a detailed meta-analysis of all observational studies published regarding this subject. A literature search in the PubMed database was undertaken through April 2012, looking for observational studies evaluating the association between statin use and risk of PD. Combined relative risk (RR) estimates and 95 % confidence intervals (CIs) were calculated using a random-effects model. Subgroup and sensitivity analyses were also performed. A total of eight (five case–control and three cohort) studies contributed to the analysis. There was heterogeneity and publication bias among the studies. Statin use significantly reduced the risk of PD by 23 % (RR 0.77, 95 % CI 0.64–0.92, p = 0.005). However, long-term statin use did not significantly affect the risk of PD (RR 0.72, 95 % CI 0.45–1.13, p = 0.15). Stratification of studies by age and smoking status significantly affected the final estimate (age-adjusted RR 0.61, 95 % CI 0.42–0.86, p = 0.005; age-not-adjusted RR 0.93, 95 % CI 0.83–1.05, p = 0.23 and smoking-adjusted RR 0.60, 95 % CI 0.42–0.87, p = 0.007; smoking-not-adjusted RR 0.92, 95 % CI 0.82–1.02, p = 0.10). Furthermore, sensitivity analysis confirmed the stability of results. Our meta-analysis supports the hypothesis that statin use reduced the risk of PD. Nevertheless, more randomized clinical trials and observational studies are required to confirm this association with underlying biological mechanisms in the future.     

Association between REM sleep behavior disorder and impulsive–compulsive behaviors in Parkinson’s disease: a systematic review and meta-analysis of observational studies

Journal of Neurology - Both REM sleep behavior disorder (RBD) and impulsive–compulsive behaviors (ICBs) are well-recognized non-motor features in patients with Parkinson’s disease (PD)....     

Indications of a dose–response relationship between cannabis use and age at onset in bipolar disorder

Cannabis use seems to play a causal role in the development of psychotic disorders. Recent evidence suggests that it may also precipitate onset in bipolar disorder. We here investigate if there is a dose–response relationship between cannabis use and age at onset in bipolar disorder, and whether there are interactions between cannabis use and illness characteristics (presenting polarity and presence of psychosis). Consecutively recruited patients with a DSM-IV, SCID verified diagnosis of bipolar I, II or NOS disorder (n=324) participated. Two-way ANCOVAS were used to investigate the effect of levels of cannabis use (<10 times during one month lifetime, >10 times during one month lifetime or a cannabis use disorder) on age at onset, including interaction effects with illness characteristics, while controlling for possible confounders. There was a significant association indicating a dose–response relationship between cannabis use and age at onset, which remained statistically significant after controlling for possible confounders (gender, bipolar subtype, family history of severe mental illness and alcohol or other substance use disorders). There were no interaction effects between cannabis use and presenting polarity or presence of psychosis. Doses of cannabis used may affect the age at onset of bipolar disorder.     

Association between morningness–eveningness and the severity of compulsive Internet use: the moderating role of gender and parenting style

BackgroundEveningness and Internet addiction are major concerns in adolescence and young adulthood. We investigated the relationship between morningness–eveningness and compulsive Internet use in young adults and explored the moderating effects of perceived parenting styles and family support on such relationships.MethodsThe participants consisted of 2731 incoming college students (men, 52.4%; mean age, 19.4 ± 3.6 years) from a National University in Taiwan. Each participant completed the questionnaires, which included the Morningness–Eveningness Scale (MES), the Yale-Brown Obsessive Compulsive Scale modified for Internet use (YBOCS-IU), the Parental Bonding Instrument for parenting style, the Family Adaptation, Partnership, Growth, Affection, and Resolve questionnaire (APGAR) for perceived family support, and the Adult Self-Report Inventory-4 (ASRI-4) for psychopathology. The morning (n = 459), intermediate (n = 1878), and evening (n = 394) groups were operationally defined by the MES t scores.ResultsThe results showed that eveningness was associated with greater weekend sleep compensation, increased compulsive Internet use, more anxiety, poorer parenting styles, and less family support; additionally, the most associated variables for increased compulsive Internet use were the tendency of eveningness, male gender, more anxiety symptoms, less maternal affection/care, and a lower level of perceived family support. The negative association between the morning type and compulsive Internet use severity escalated with increased maternal affection/care and decreased with increased perceived family support. The positive association between the evening type and compulsive Internet use severity declined with increased maternal protection. However, the father’s parenting style did not influence the relationship between morningness–eveningness and compulsive Internet use severity.ConclusionsOur findings imply that sleep schedule and the parental and family process should be part of specific measures for prevention and intervention of compulsive Internet use.     

Efficacy and safety of anti-inflammatory agents in treatment of psychotic disorders – A comprehensive systematic review and meta-analysis

ObjectiveAntipsychotic effects of immunomodulating drugs have been suggested; however, a thorough, comprehensive meta-analysis on the effect and safety of anti-inflammatory add-on treatment on psychotic disorders is lacking.MethodMultiple databases were searched up until February 2020. Only double-blinded, randomized, placebo-controlled clinical trials (RCTs) were included. Primary outcomes were change in total psychopathology and adverse events. Secondary outcomes included, amongst others, positive and negative symptoms, general psychopathology and cognitive domains. We performed random-effects meta-analyses estimating mean differences (MD) and standardized mean differences (SMD) for effect sizes.ResultsSeventy RCTs (N = 4104) were included, investigating either primarily anti-inflammatory drugs, i.e. drugs developed for immunomodulation, such as NSAIDs, minocycline and monoclonal antibodies (k = 15), or drugs with potential anti-inflammatory properties (k = 55), e.g. neurosteroids, N-acetyl cysteine, estrogens, fatty acids, statins, and glitazones. Antipsychotics plus anti-inflammatory treatment, compared to antipsychotics plus placebo, was associated with a PANSS scale MD improvement of -4.57 (95%CI = -5.93 to -3.20) points, corresponding to a SMD effect size of -0.29 (95%CI = -0.40 to -0.19). Trials on schizophrenia (MD = -6.80; 95%CI, -9.08 to -4.52) showed greater improvement (p < 0.01) than trials also including other psychotic disorders. However, primarily anti-inflammatory drugs (MD = 4.00; 95%CI = -7.19 to -0.80) were not superior (p = 0.69) to potential anti-inflammatory drugs (MD = 4.71; 95%CI = -6.26 to -3.17). Furthermore, meta-regression found that smaller studies showed significantly larger effect sizes than the larger studies (p = 0.0085), and only 2 studies had low risk of bias on all domains. Small but significant effects were found on negative symptoms (MD = -1.29), positive symptoms (MD = -0.53), general psychopathology (MD = -1.50) and working memory (SMD = 0.21). No differences were found regarding adverse events, but only 26 studies reported hereon.ConclusionsAnti-inflammatory add-on treatment to antipsychotics showed improvement of psychotic disorders; however, no superiority was found in primarily anti-inflammatory drugs, raising the question of the mechanism behind the effect, and treatment effect might be overestimated due to the large number of small studies.     

Association between actigraphy-based sleep duration variability and cardiovascular risk factors – Results of a population-based study

BackgroundAlthough a few studies suggest an adverse effect of sleep duration variability on cardiovascular risk factor, others did not and this association remains controversial. Moreover, most studies were non-representative of the general population, used different sleep duration variability measures, and relied on self-reported sleep duration. We aimed to assess the association between different, actigraphy-based sleep duration variability measures and cardiovascular risk factors in a population-based sample.MethodsIn a middle-aged population-based cohort, 2598 subjects had data on sleep duration variability measured by actigraph over 14 days. Multivariable logistic regressions were performed to assess the relationship between different sleep duration variability measures [ie, night-to-night variability (NNV), range between shortest and longest sleep duration (RSL), range between average weekday and weekend sleep duration (RWW)] and cardiovascular risk factors including obesity, diabetes and hypertension.ResultsSubjects with highest sleep duration variability - measured as NNV, RSL and RWW, were more likely to be obese. These associations robust in most but not all sensitivity analyses, and no associations between sleep duration variability measures and diabetes or hypertension were found.ConclusionThere is a possible association between high sleep duration variability and obesity, although results were not robust in all sensitivity analyses. Further, no associations between sleep duration variability and other cardiovascular risk factor such as diabetes or hypertension were found.     

Lack of association between TNFα rs1800629 polymorphism and schizophrenia risk: A meta-analysis

Evidence has suggested that tumour necrosis factor α (TNFα) may be involved in the aetiology of schizophrenia, but the underlying association between TNFα-308G/A polymorphism (rs1800629) and schizophrenia risk is still ambiguous. This meta-analysis was performed to quantitatively summarise the evidence for such a relationship. Eligible studies were identified by searching PubMed, EMBASE, CNKI (China National Knowledge Infrastructure), CBM (Chinese Biomedical Literature Database) and WANFANG databases within a range of published years from 1990 to July 2012. The odds ratio (OR) corresponding to the 95% confidence interval (CI) was used to assess the different associations. Twenty-one studies with 4340 cases and 5745 controls were included in this meta-analysis. The pooled examination displayed that there was no significant association between TNFα-308G/A polymorphism and susceptibility to schizophrenia overall (OR=1.047, 95% CI=0.876–1.253, P=0.614 for A vs. G), and no difference in Caucasian subgroup (OR=1.041, 95% CI=0.815–1.331, P=0.747) and Asian subgroup (OR=1.057, 95% CI=0.807–1.386, P=0.686). Lack of association was also found in males (OR=0.862, 95% CI=0.413–1.797, P=0.692) and females (OR=0.797, 95% CI=0.579–1.097, P=0.163) with a dominant model. Taken together, this meta-analysis suggests that TNFα-308G/A polymorphism may not be associated with schizophrenia susceptibility.     

Association between two α-2-macroglobulin gene polymorphisms and Parkinson's disease: a meta-analysis

Purpose: Due to the controversial results in assessment of the association between α-2-Macroglobulin gene (A2M) polymorphisms and Parkinson's disease (PD), we performed a meta-analysis to evaluate the relationship between two A2M variants (rs669 and rs3832852) and PD. Methods: All eligible studies were retrieved in PubMed, Web of Science, Embase and PDGene databases. Data were extracted by two investigators independently. All the four genetic models were used for rs669 and rs3832852. Results: A total of 877 PD patients and 1296 controls from six studies were included for rs669 polymorphisms. The combined odds ratio (OR) indicated that rs669 polymorphisms were likely associated increased risk of PD only in dominant genetic models (OR = 1.41, CI = 1.03–1.92), especially in Asian subgroup (OR = 1.97, CI = 1.03–3.75). Five studies containing 772 PD patients and 1178 controls were identified for rs3832852 polymorphisms. The result suggested that rs3832852 polymorphisms were not associated with PD in all genetic models. Conclusions: Our data indicate that the rs669 (A/G) polymorphisms in A2M gene are associated with increased risk in PD. To further validate the association of A2M polymorphisms with PD, more studies with larger samples are required.     

Relationship between trunk muscle strength,reaching ability and balance in children with Down syndrome – A cross-sectional study

BackgroundChildren with Down Syndrome (DS) present with neuromuscular disturbances leading to delayed developmental milestones, poor quality of movement and poor balance. The aim of this study is to discuss the role of trunk muscle strength in the functional performance of children with DS.Methodology28 children were recruited in the study, 14 with DS and 14 age and gender-matched controls. Trunk muscle strength, reaching ability and balance were assessed using a Handheld Dynamometer, Modified Functional Reach test and Pediatric Balance Scale, respectively.ResultsChildren with DS present with poorer trunk muscle strength, reaching ability and balance as compared to typically developing (TD) children. There was a positive correlation between trunk muscle strength and lateral reaching in children with DS. A strong to moderate correlation was observed between the trunk muscle strength and balance in children with DS.DiscussionChildren with DS demonstrated a significantly weak trunk muscle groups. Lateral reaching distance is reduced due to the poor proximal control and they present with near-normal forward reach distance attributed to compensation using the lower trunk muscles. They exhibit poor balance in the components that require a small base of support.ConclusionChildren with DS exhibit weak trunk muscles along with lesser reaching distance and poor balance. Also, trunk muscle strength influences lateral reaching ability. Trunk muscle strength, mainly trunk extensors impacted functional balance in sitting, standing and while performing transfers.     

Is meat consumption associated with depression? A meta-analysis of observational studies

Background

A number of epidemiological studies have examined the effect of meat consumption on depression. However, no conclusion has been reached. The aim of this study was to examine the relationship between meat consumption and depression.

Methods

The electronic databases of PUBMED and EMBASE were searched up to March 2017, for observational studies that examined the relationship between meat consumption and depression. The pooled odds ratio (OR) for the prevalence of depression and the relative risk (RR) for the incidence of depression, as well as their corresponding 95% confidence interval (CI), were calculated respectively (the highest versus the lowest category of meat consumption).

Results

A total of eight observational studies (three cross-sectional, three cohort and two case-control studies) were included in this meta-analysis. Specifically, six studies were related to the prevalence of depression, and the overall multi-variable adjusted OR suggested no significant association between meat consumption and the prevalence of depression (OR?=?0.89, 95% CI: 0.65 to 1.22; P?=?0.469). In contrast, for the three studies related to the incidence of depression, the overall multi-variable adjusted RR evidenced an association between meat consumption and a moderately higher incidence of depression (RR?=?1.13, 95% CI: 1.03 to 1.24; P?=?0.013).

Conclusions

Meat consumption may be associated with a moderately higher risk of depression. However, it still warrants further studies to confirm such findings due to the limited number of prospective studies.

     

Association between obstructive sleep apnoea syndrome and the risk of cardiovascular diseases: an updated systematic review and dose–response meta-analysis

ObjectiveThe aim of this study was to summarize the evidence concerning the relationship between obstructive sleep apnoea syndrome (OSAS) and the risk of cardiovascular diseases (CVDs).MethodsA systematic search was carried out using PubMed and Web of Science up to September 10, 2019. Categorical as well as linear and non-linear dose–response meta-analyses were respectively performed to evaluate the association between the severity of OSAS and the risk of CVDs. Apnoea-hypopnea index (AHI) was used as an indicator of OSAS severity.ResultsThis study included 10 cohort studies targeting a total of 36,347 subjects and 3362 patients with CVDs. The pooled RRs of overall CVDs were 1.13 (95% confidence interval [CI] = 1.02–1.24) for mild versus non/normal OSAS, 1.16 (95% CI = 1.02–1.32) for moderate versus non/normal OSAS, 1.26 (95% CI = 1.15–1.39) for moderate-severe versus non/normal OSAS, and 1.41 (95% CI = 1.22–1.63) for severe versus non/normal OSAS. The linear dose–response meta-analysis showed that every 10 events/hour increment in AHI value was associated with a 9% increased risk of suffering from CVDs. The non-linear dose–response meta-analysis showed that the risk of CVDs increased continuously with the increment in AHI.ConclusionThe present systematic review and meta-analysis provide evidence for a positive association between OSAS and the risk of CVDs, despite the severity of OSAS. The relative risk of CVDs increases continuously with the increment in AHI.     

Association between CLU gene rs11136000 polymorphism and Alzheimer’s disease: an updated meta-analysis

Large-scale genome-wide association studies (GWAS) identified that the single nucleotide polymorphism rs11136000 in Clusterin (CLU) gene was associated with risk of Alzheimer’s disease (AD) in Caucasian ancestry. However, recent studies reported either a weak association or no association between rs11136000 polymorphism and AD in Asian populations. Therefore, we performed a meta-analysis to explore whether rs11136000 polymorphism is associated with susceptibility to AD in Asian populations. A total of 17 articles including 26 studies with 19,829 cases and 30,900 controls, which were identified by searching PubMed, MEDLINE, and AlzGene up to Nov 2016, were collected for this meta-analysis. The significant association between rs11136000 and AD in the pooled population was found under all the models. In subgroup analysis, we identified significant association in Asian population under the additive mode (OR?=?0.90, 95% CI?=?0.85–0.96) but not in the recessive model (OR?=?0.80, 95% CI?=?0.53–1.21) and the dominant model (OR?=?0.94, 95% CI?=?0.86–1.03). Our analysis further supports previous findings that the rs11136000 polymorphism C allele is associated with AD susceptibility. To our knowledge, this is the new largest meta-analysis to access to the association of CLU rs11136000 polymorphism with AD risk.     

Nut consumption and the risk of coronary artery disease: A dose–response meta-analysis of 13 prospective studies

Introduction

Epidemiological studies evaluating the association of nut with risk of coronary artery disease (CAD) have produced inconsistent results. We conducted a meta-analysis to summarize the evidence from prospective cohort studies regarding the association between nut consumption and risk of CAD.

Materials and methods

Pertinent studies were identified by searching Web of Knowledge, Pubmed and Wan Fang Med Online up to January 2014. Random-effect model was used to combine the results. Dose–response relationship was assessed by restricted cubic spline. Publication bias was estimated using Begg’ funnel plot and Egger’s regression asymmetry test.

Results

Nine articles with 13 prospective studies involving 6,127 CAD cases and 347,477 participants were included in this meta-analysis. Pooled results suggested that highest nut consumption amount versus lowest amount was significantly associated with the risk of CAD [summary relative risk (RR) = 0.660, 95%CI = 0.581-0.748, I² = 39.6%]. Linear dose–response relationship was found between nut consumption and CAD risk, and the risk of CAD decreased by 5% for every 1 serving/week increase intake of nut. A protective effect for CAD was found when consumed more than 2 servings/week of nut. The RR of CAD was 0.96 (0.89-1.02), 0.91 (0.82-0.99), 0.85 (0.77-0.95), 0.80 (0.72-0.89), 0.75 (0.65- 0.85) and 0.70 (0.58-0.83) for 1, 2, 3, 4, 5 and 6 servings/week of nut consumption, respectively.

Conclusions

Our analysis indicated that nut consumption has a protective effect on CAD.     

Serotonin transporter genotype 5HTTLPR as a marker of differential susceptibility? A meta-analysis of child and adolescent gene-by-environment studies

We present results of a meta-analysis of gene-by-environment (G × E) studies involving the serotonin transporter genotype 5HTTLPR to evaluate empirical support for two competing conceptual frameworks in developmental psychopathology: diathesis-stress and differential susceptibility. From a diathesis-stress perspective, the cumulative negative effects of the short allele (ss and sl genotypes) and adverse environments on development have been stressed. From a differential-susceptibility perspective, carriers of the s allele are predicted to be more open to adverse as well as positive environments, for better and for worse. Studies with children and adolescents up to 18 years of age (N=9361) were included. We found 41 effect sizes (N=5863) for the association between negative environments and developmental outcomes with or without significant moderation by 5HTTLPR genotype and 36 effect sizes (N=3498) for the potentially 5HTTLPR-moderated association between positive environments and developmental outcomes. Five moderators were examined: age, ethnicity, genotyping (biallelic or triallelic) and methods used to assess environment and outcome. In the total set of studies, including studies with mixed ethnicities, we found that ss/sl carriers were significantly more vulnerable to negative environments than ll carriers, thus supporting the diathesis-stress model. In the Caucasian samples, however, ss/sl carriers also profited significantly more from positive environmental input than ll carriers. Associations between (positive or negative) environment and (positive or negative) developmental outcome were absent for ll carriers. The meta-analytic findings support the hypothesis that in Caucasian samples 5HTTLPR is a genetic marker of differential susceptibility. G × E interactions might be critically dependent on ethnicity.     

Leptin in adolescent idiopathic scoliosis – A meta-analysis

To compare the serum levels of leptin and soluble leptin receptor (sOB-R) with adolescent idiopathic scoliosis (AIS) girls and controls through meta-analysis. The MEDLINE via PubMed, Cochrane, Scopus, and EMBASE database, from the earliest available date of indexing between January 2010 and January 2019, were searched for comparative studies evaluating serum levels of leptin and sOB-R in AIS girls. Two authors performed the data extraction independently. Any discrepancies were resolved by a consensus. Six comparative studies were identified. There was no statistically significant difference in terms of leptin between AIS girls and control [p = 0.19, WMD = −2.06 (−5.14, 1.03) ng/mL]. However, the sOB-R level was significantly higher [p < 0.00001, WMD = 2.85 (1.81, 3.88) ng/mL] and the free leptin index was significantly lower [p = 0.0006, WMD = −0.12 (−0.19, −0.05)] in AIS girls than those of healthy control girls. The body mass index was significantly lower in AIS girls [p = 0.03, WMD = −1.53 (−2.95, −0.12) kg/m²]. The current meta-analysis showed that the level of sOB-R is higher in AIS patients than controls, while the concentration of leptin remains unchanged in AIS patients. Further well-designed studies would be necessary to substantiate our results.     

Brain tumor location and psychiatric symptoms: is there any association? A meta-analysis of published case studies

A meta-analytic study of reports of brain tumors and psychiatric symptoms for the past 50 years was conducted to examine potential associations between tumor location and psychiatric symptoms. Results demonstrated that there is a statistically significant association between anorexia symptoms and hypothalamic tumors. For the rest of the brain regions a statistically significant association could not be definitively determined. However, several of the regions demonstrated an increased likelihood of associated symptoms when compared with other regions. The methodological limitations of this analysis are discussed.