Serotonin transporter polymorphism and LDL-cholesterol

Serum Lipid Levels and Suicidal Ideation of Adults: A Cross-Sectional Study Using the Korea National Health and Nutrition Examination Survey

Cholesterol plays a crucial role in the brain, which suggests that changes in its concentration levels may have an impact on the central nervous system. To examine the association between serum lipid levels and suicidal ideation according to sex, we performed a cross-sectional study using data from the Korea National Health and Nutrition Examination Survey 2014-2018. A total of 13,772 adults 19 years or older were analyzed. The ninth item of the Patient Health Questionnaire was used to evaluate the suicidal ideation of participants. After sorting by sex, a complex logistic regression was performed to measure the association between serum lipid indicators and suicidal ideation. The analysis adjusted for age, body mass index, smoking, heavy drinking, regular exercise, household income, education level, dyslipidemia medication, depression, and chronic diseases. Compared to the intermediated category, the lowest range of low-density lipoprotein cholesterol (LDL-C; <100 mg/dL) was associated with increased suicidal ideation in men (odds ratio [OR] = 1.97; 95% confidence interval [CI]: 1.30-3.01). The association between lipid levels and suicidal ideation was not clear in women. We found an association between lower LDL-C levels and an increased risk of suicidal ideation among Korean men aged 19 years or older.

Association between serum lipid concentrations and attempted suicide in patients with major depressive disorder: A meta-analysis

Background

There is growing evidence that serum lipid concentrations may be associated with attempted suicide in patients with major depressive disorder (MDD), but these findings remain controversial. Thus, we performed a comprehensive meta-analysis to quantitatively assess the associations between serum lipid concentrations and attempted suicide in MDD patients.

Materials and methods

Electronic databases (PubMed, Embase, the Cochrane Library and the China National Knowledge Library) were searched for relevant literature up to 10 February 2020. We used a random-effects model based on heterogeneity amongst studies and generated pooled standardised mean differences (SMDs).

Results

Thirty-two studies comprising 7,068 subjects met the inclusion criteria. A pooled analysis showed that compared with non-attempters, MDD patients who had attempted suicide had significantly lower serum concentrations of total cholesterol (TC) (SMD: -0.63, 95% CI: -0.83 to -0.44) and low-density lipoprotein cholesterol (LDL-C) (SMD: -0.69, 95% CI: -1.04 to -0.34), but the serum concentrations of high-density lipoprotein cholesterol (HDL-C) (SMD: -0.12, 95% CI: -0.33 to 0.10) and triglycerides (TGs) (SMD: 0.00, 95% CI: -0.20 to 0.20) were not significantly different between the two groups. Subgroup and meta-regression analysis indicated that heterogeneity with respect to TC concentrations may be due to different ages (p = 0.041) and sample sizes (p = 0.016) of studies, and that heterogeneity with respect to HDL-C concentrations may be partly due to different settings of studies (p = 0.017).

Conclusions

This meta-analysis demonstrated that lower concentrations of TC and LDL-C, but not of HDL-C and TGs, were associated with attempted suicide in MDD patients. This indicates that TC and LDL-C may be useful as biological markers for predicting whether MDD patients may attempt to commit suicide.

Attention-deficit/hyperactivity disorder is associated with reduced levels of serum low-density lipoprotein cholesterol in adolescents. Data from the population-based German KiGGS study

Objectives: Attention-deficit/hyperactivity disorder (ADHD) is a multifactorial, complex and the most common neurodevelopmental disorder in childhood. In this analysis, we tested the hypothesis that altered serum lipid patterns are associated with ADHD. Methods: Using data from the nationwide, population-based German Health Interview and Examination Survey for Children and Adolescents (KiGGS), we compared serum levels of total cholesterol, high-density (HDL) and low-density lipoprotein (LDL) cholesterol, and also triglycerides, in participants with physician-diagnosed and/or suspected ADHD, as defined by a value of ≥7 on the hyperactivity-inattention subscale of the Strengths and Difficulties Questionnaire (SDQ), with non-ADHD controls. Results: Among 6,898 participants aged between 11 and 17 years, 666 (9.7%) had a physician-based diagnosis of ADHD and/or suspected ADHD. We found correlations between the parent-rated SDQ scores on the hyperactivity-inattention subscale and concentrations of triglycerides (r = 0.064, p < .001), total cholesterol (r = -0.026, p = .033), HDL cholesterol (r = -0.059, p < .001) and LDL cholesterol (r = -0.027, p = .031). In multivariate models, low serum levels of LDL cholesterol remained a significant predictor of ADHD (Exp(β) = 0.382, 95% confidence interval = 0.165-0.888, p = .025). Conclusions: Our findings in a large, nationwide and representative sample of German adolescents demonstrated a small, but significant and inverse link between LDL cholesterol levels and symptoms of ADHD. Further studies are required to decipher the biochemical mechanisms behind this relationship.

[Dyslipidemia and suicidal risk in patients with psychiatric disorders]

The aim of this work is to study the association between dyslipidemia and suicidal risk in patients with psychiatric pathology. Our study has involved 155 patients suffering from major depressive disorder and 124 schizophrenic patients aged 40.58±12.16 and 43.43±10.60 years, respectively. Total cholesterol (TC), triglycerides (TG) and HDL-c were determined by enzymatic methods, LDL-c was calculated by the Friedewald formula. Plasma cholesterol level was significantly lower among suicidal schizophrenic or depressive patients. There were no significant differences in the others lipid levels. The results of our study suggest that total cholesterol values less than 3.59mmol/L could be an indicator of suicide vulnerability in patients with schizophrenia or major depressive disorder.

Population differences in associations of serotonin transporter promoter polymorphism (5HTTLPR) di- and triallelic genotypes with blood pressure and hypertension prevalence

Based on prior research finding the 5HTTLPR L allele associated with increased cardiovascular reactivity to laboratory stressors and increased risk of myocardial infarction, we hypothesized that the 5HTTLPR L allele will be associated with increased blood pressure (BP) and increased hypertension prevalence in 2 large nationally representative samples in the United States and Singapore.

METHODS

Logistic regression and linear models tested associations between triallelic (L'S', based on rs25531) 5HTTLPR genotypes and hypertension severity and mean systolic and diastolic blood pressure (SBP and DBP) collected during the Wave IV survey of the National Longitudinal Study of Adolescent to Adult Health (Add Health, N=11,815) in 2008-09 and during 2004-07 in 4196 Singaporeans.

RESULTS

In US Whites, L' allele carriers had higher SBP (0.9 mm Hg, 95% CI=0.26-1.56) and greater odds (OR=1.23, 95% CI=1.10-1.38) of more severe hypertension than those with S'S' genotypes. In African Americans, L' carriers had lower mean SBP (-1.27mm Hg, 95% CI=-2.53 to -0.01) and lower odds (OR = 0.78, 95% CI=0.65-0.94) of more severe hypertension than those with the S'S' genotype. In African Americans, those with L'L' genotypes had lower DBP (-1.13mm Hg, 95% CI=-2.09 to -0.16) than S' carriers. In Native Americans, L' carriers had lower SBP (-6.05mm Hg, 95% CI=-9.59 to -2.51) and lower odds of hypertension (OR = 0.34, 95% CI=0.13-0.89) than those with the S'S' genotype. In Asian/Pacific Islanders those carrying the L' allele had lower DBP (-1.77mm Hg, 95% CI=-3.16 to -0.38) and lower odds of hypertension (OR = 0.68, 95% CI=0.48-0.96) than those with S'S'. In the Singapore sample S' carriers had higher SBP (3.02mm Hg, 95% CI=0.54-5.51) and DBP (1.90mm Hg, 95% CI=0.49-3.31) than those with the L'L' genotype.

CONCLUSIONS

These findings suggest that Whites carrying the L' allele, African Americans and Native Americans with the S'S' genotype, and Asians carrying the S' allele will be found to be at higher risk of developing cardiovascular disease and may benefit from preventive measures.

Is low total cholesterol levels associated with suicide attempt in depressive patients?

BACKGROUND

Patients with major depressive disorder (MDD) have a high risk of suicide. Many pathophysiological factors involved in MDD and suicide such us a low cholesterol levels have been associated with MDD and increased vulnerability to suicide. In this study, we investigate the relation between lipid parameters and suicide risk in patients with MDD.

METHODS

Plasma levels of total cholesterol, triglycerides, and high-density lipoprotein cholesterol (HDL-c) and low-density lipoprotein cholesterol (LDL-c) were determined in 160 patients meeting the DSM-IV-TR criteria for MDD (110 patients without suicidal behavior and 52 suicidal attempters) and 151 healthy controls.

RESULTS

A significant decrease in plasma cholesterol levels was observed in the group of suicidal depressive patients compared to those without suicidal behavior (p < 0.001). For the other lipid levels (triglycerides, HDL cholesterol, and LDL cholesterol), there were no significant differences between suicidal and non-suicidal patients.

CONCLUSIONS

Our study showed a significant decrease in plasma cholesterol levels in suicidal patients. This result support the hypothesis of the association of low plasma cholesterol level and suicidal behavior in patients with major depressive disorder.

Antidepressants with a high serotonin reuptake transporter affinity and serum lipid levels in a population-based study in older adults

OBJECTIVE

We aimed to investigate the association between antidepressants and serum lipid levels in a population-based study in older adults.

METHODS

We included participants from the prospective Rotterdam Study with data on lipid levels (total, low-density lipoprotein (LDL) and high-density lipoprotein cholesterol, and triglycerides). We classified antidepressants based on binding affinity to the serotonin transporter (low/intermediate- and high-affinity antidepressants). We compared lipid levels in users of these groups of antidepressants with lipid levels in non-users. Furthermore, we studied effect modification by the 102 C>T polymorphism (HTR2A gene), which is associated with antidepressant drug response and metabolic outcomes.

RESULTS

Compared with non-users (N = 6438), LDL cholesterol level was higher (2.9 versus 3.1 mmol/L, respectively; p = 0.05) in users of high-affinity antidepressants (N = 89). Similar levels of the other lipids were observed between the groups for the other lipids. The mean difference in serum LDL cholesterol level between non-users and users of high-affinity antidepressants was largest in participants with the CC genotype compared with the other genotypes (notably 0.47 mmol/L), indicative of effect modification (p-value for interaction = 0.03).

CONCLUSION

Antidepressants with a high serotonin reuptake transporter affinity were associated with higher LDL cholesterol levels, which were modified by a common genetic variation in the HTR2A gene.

Suicidal behaviour and lipid levels in unipolar and bipolar depression

INTRODUCTION

Evidence for a possible association between a low level of cholesterol and increased suicidal behaviour has accumulated in the recent 3 decades. The present study investigates whether lipid levels can make state-dependent markers of suicidal behaviour in Polish patients with mood disorder recently admitted to a psychiatric hospital owing to an acute depressive episode.

MATERIALS AND METHODS

The study was conducted on 223 patients (73 male and 150 female) with unipolar (n=171) and bipolar (n=52) depression. They were interviewed to assess any occurrence of suicidal thoughts, suicidal tendencies and/or suicidal attempts during the 3 months before admission. Laboratory measurements [total cholesterol, low density lipoprotein (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, triglycerides and total lipids] were obtained within 24-72 h after hospital admission.

RESULTS

Suicidal thoughts, tendencies, and attempts were associated with low total cholesterol, LDL cholesterol, and total lipids in both male and female patients, in both diagnostic categories. Triglycerides were significantly lower in male and female patients with suicidal thoughts compared with their non-suicidal counterparts. No association with suicidality was found with HDL cholesterol.

CONCLUSIONS

The results of our study support a majority of research showing the association in depressed patients between suicidal behaviour and low levels of total and LDL cholesterol. In addition, the data suggest a similar association with low total lipids, and in some instances, with low triglycerides.

Suicidal behavior in schizophrenia may be related to low lipid levels

Background

Lifetime suicide mortality in people with schizophrenia is approximately 4–5%, which is higher than in the general population. In mood disorders, many studies and meta-analyses have shown a link between suicidal behavior and low lipid levels, especially that of cholesterol, and some studies have also suggested such a relationship in schizophrenia. Therefore, the aim of the present study was to investigate a possible correlation between suicidal behavior and lipid levels in schizophrenia patients recently admitted to a psychiatric hospital.

Material/Methods

Our study included 148 (69 males, 79 females) schizophrenia patients with a mean age of 32±10 years, all recently admitted due to acute exacerbation of their mental illness. Psychometric and laboratory assessments were made within 24–72 hours after hospital admission. The main purpose of the interview was to assess occurrence of any suicidal thoughts, suicidal tendencies, and/or suicide attempts during the 3 months prior to admission. Serum total, LDL and HDL cholesterol, as well as triglycerides and total lipids were measured.

Results

A significant association was found between suicidal thoughts and attempts and low total cholesterol, LDL cholesterol, triglycerides, and total lipids, in both male and female patients. In male patients with suicidal tendencies, correlation with low LDL cholesterol and triglycerides did not reach statistical significance. No association with suicidality was found with HDL cholesterol in subjects studied.

Conclusions

The results obtained suggest that, similar to depressed patients, low total and LDL cholesterol, triglycerides, and total lipids can be state-dependent risk factors for suicidal behavior in Polish patients with schizophrenia.

The association between serum lipid levels, suicide ideation, and central serotonergic activity in patients with major depressive disorder

BACKGROUND

There is some evidence that low lipid levels cause suicide in depressed patients. The purpose of this study was to identify whether low serum lipid levels are associated with suicide ideation or are correlated with central serotonin function.

METHODS

Auditory processing for the loudness dependence of auditory evoked potentials (LDAEP) was measured in 73 outpatients with major depressive disorder. The Hamilton Depression Rating Scale (HAMD) and the Beck Depression Inventory (BDI) were administered on the same day as measurement of the LDAEP. In addition, serum levels of total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglyceride (TG) levels were measured. All subjects had received antidepressant monotherapy.

RESULTS

The depressed subjects were divided into those with and without suicide ideation according to the score for HAMD item 3 or BDI item 9. TG levels differed significantly between the two groups, whereas body mass index (BMI), total cholesterol, LDL, HDL, and LDAEP did not. The scores for HAMD item 3 and BDI item 9 were negatively correlated with TG levels (p=0.045 and 0.026, respectively). The LDAEP was negatively correlated with TG levels (p=0.012). Although there was tendency toward a negative correlation between the LDAEP and serum LDL, it did not reach statistical significance (p=0.068).

LIMITATIONS

The cross-sectional design of this study means that baseline serum lipid levels were not measured.

CONCLUSION

The findings of this study revealed a relationship between TG and suicide ideation that is independent of both BMI and body weight. Furthermore, serum lipid levels were associated with central serotonergic activity, as assessed using the LDAEP.

Association between cholesterol plasma levels and craving among heroin users

OBJECTIVE

Lipids may play some roles in the central nervous system functions that are associated with drug addiction. To date, cholesterol is known to influence relapse of cocaine use. However, the relationship between cholesterol and heroin craving is unclear. This study examined the concurrent association between cholesterol and craving.

METHOD

The serum lipid levels of 70 heroin users who were undergoing or had undergone a methadone maintenance therapy were measured. Their craving and demographic data were assessed.

RESULTS

Total cholesterol and low-density lipoprotein cholesterol are negatively associated with craving before (r = -0.33, P < 0.01, and r = -0.36, P < 0.01, respectively) and after controlling for the effects of potential confounders (β = -0.38, P < 0.01, and β = -0.42, P < 0.01, respectively).

CONCLUSIONS

Cholesterol could be associated with the cognitive aspect of craving and may be a potential marker to predict risk of drug relapse.

The Relationships between Cholesterol and Suicide: An Update

Cholesterol is a core component of the central nervous system, essential for the cell membrane stability and the correct functioning of neurotransmission. It has been observed that cholesterol may be somewhat associated with suicidal behaviours. Therefore, the aim of this paper was to elucidate current facts and views about the role of cholesterol levels in mood disorders. The majority of the studies reviewed in the present paper suggest an interesting relationship between cholesterol (especially lower levels) and suicidality. On the other hand, particularly during the last years, relationships between serum cholesterol and suicidality were doubted on the basis of some recent studies that have not found any correlation. However, the debate on relationships between cholesterol and suicide is open and longitudinal studies on a larger sample of patients are needed to further clarify this important issue.

Depressive symptoms and serum lipid levels in young adult women

Accumulating data suggest that depression is associated with risk factors for cardiovascular disease, but few studies have investigated potential behavioral mediators of such associations, particularly among women. In this study of healthy young adult women (n = 225), we examined associations among depressive symptoms, health behaviors, and serum lipid levels. Depressive symptoms were assessed with the 20-item Center for Epidemiologic Studies-Depression scale, and a fasting blood sample was obtained for serum lipid levels, including total cholesterol, high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C). Diet was measured using 24-h recalls, and other health behaviors (physical activity, smoking) were assessed via self-report questionnaire. Results indicated a modest negative association between depressive symptoms and LDL-C levels. Higher levels of depressive symptoms were also associated with lower total and insoluble dietary fiber intake, both of which were associated with HDL-C and LDL-C. Mediational analyses indicated a significant indirect effect of depressive symptoms on LDL-C via total and insoluble dietary fiber in unadjusted analyses, but not in adjusted analyses. The present findings suggest that depressive symptoms are inversely associated with serum LDL-C levels in young adult women, but that these associations are not likely mediated by adverse lifestyle behaviors.

The relationship between serotonin transporter gene promoter polymorphism and serum lipid levels at young age in a longitudinal population-representative study

The serotonin transporter gene promoter region polymorphism (5-HTTLPR) has been linked to psychiatric disorders, mostly anxiety and affective disorders. In elderly populations 5-HTTLPR polymorphism has also been reported to be associated with serum lipid levels. We have examined the interaction of the 5-HTTLPR polymorphism and the markers of lipid metabolism at young age in a longitudinal, population-representative cohort study. The sample of the Estonian Children Personality Behaviour and Health Study (initially cohorts of 9 and 15 year old children, complete lipid and genotype data for n=1176) was examined throughout 10 years. Subjects were genotyped and the levels of low-density lipoproteins, high-density lipoproteins, triglycerides, and total cholesterol were measured. Children and adolescents carrying the s allele of the 5-HTTLPR polymorphism had lower levels of low-density lipoprotein and total cholesterol. At the age of 25, the s allele carriers had higher levels of high-density lipoproteins. These associations were independent of gender. Thus the 5-HTTLPR can be associated with the serum lipid levels and in particular low-density lipoproteins already in a young age.

Cholesterol and CSF 5-HIAA in attempted suicide

BACKGROUND

Low serum cholesterol has been linked to suicide and violent behaviour. The same kind of associations has been reported regarding low levels of 5-hydroxyindolacetic acid (5-HIAA) in the cerebrospinal fluid (CSF) and suicidal behaviour. The hypothesis of the link between serum cholesterol and suicide incorporate serotonin. It proposes that low cholesterol is related to altered serotonergic neurotransmission. A correlation between CSF 5-HIAA and serum cholesterol has been shown in animal studies, but has not been found in humans.

AIM

To study the interrelationship between serum cholesterol and CSF 5-HIAA in suicide attempters. Since both cholesterol and CSF 5-HIAA are associated with suicide and violent suicide attempts, we also investigated the correlation with suicide, violent suicide attempt method, suicide intent, hopelessness and depression severity.

METHODS

Serum total cholesterol and CSF 5-HIAA were measured in 42 medication free suicide attempters. Patients were assessed with Becks's Hopelessness scale (BHS), Suicide Intent Scale (SIS) and Montgomery-Asberg depression rating scale (MADRS) and followed-up for causes of death.

RESULTS

Serum total cholesterol and CSF 5-HIAA showed a significant positive correlation adjusted for age, body mass index and substance abuse diagnosis. Cholesterol and CSF 5-HIAA levels did not differ between violent and non-violent suicide attempters or between suicide completers and survivors.

CONCLUSIONS

These findings indicate that the serotonergic system may be connected to serum cholesterol in patients with a recent suicide attempt.

Gender and genotype modulation of the association between lipid levels and depressive symptomatology in community-dwelling elderly (the ESPRIT study)

BACKGROUND

Lipids appear to mediate depressive vulnerability in the elderly; however, sex differences and genetic vulnerability have not been taken into account in previous prospective studies.

METHODS

Depression was assessed in a population of 1040 women and 752 men aged 65 years and older at baseline and after 7-year follow-up. Clinical level of depression (DEP) was defined as having either a score of 16 or higher on the Centre for Epidemiology Studies Depression scale or a diagnosis of current major depression on the Mini-International Neuropsychiatric Interview. Lipid levels, apolipoprotein E, and serotonin transporter linked promoter region (5-serotonin transporter gene linked promoter region) genotypes were evaluated at baseline.

RESULTS

Multivariate analyses adjusted by sociodemographic and behavioral variables, measures of physical health including ischemic pathologies, and genetic vulnerability indicated gender-specific associations between dyslipidemia and DEP, independent of the use of lipid-lowering agents or apolipoprotein E status. Men with low low-density lipoprotein cholesterol levels had twice the risk of prevalent and incident DEP, whereas in women low high-density lipoprotein cholesterol levels were found to be significantly associated with increased prevalent DEP (odds ratio = 1.5) only. A significant interaction was observed between low low-density lipoprotein-cholesterol and 5-serotonin transporter gene linked promoter region genotype, men with s/s or s/l genotype being at increased risk of DEP (odds ratio = 6.0 and 2.7, respectively). No significant gene-environment interaction was observed for women.

CONCLUSIONS

DEP is associated with higher atherogenic risk in women (low high-density lipoprotein cholesterol), whereas the reverse is observed in men (low low-density lipoprotein cholesterol). Late-life depression may have a complex gender-specific etiology involving genetic vulnerability in men.

Lipid trajectories as predictors of depressive symptoms: the Young Finns Study

OBJECTIVE

The aim of this study was to identify common trajectories of lipid levels across childhood and early adulthood life span.

DESIGN

The sample was a subpopulation of 824 young adults (3 to 9 years of age at baseline in 1980) of the ongoing population-based prospective Cardiovascular Risk in Young Finns Study. Lipid levels were determined in 1980, 1983, 1986, and 2001.

MAIN OUTCOME MEASURES

Depressive symptoms were assessed using a modified version of Beck's Depression Inventory (Beck, 1967) in 1992 and 2001.

RESULTS

The 2 triglycerides trajectories (steeply vs. moderately increasing) were differently related to depressive symptoms in adulthood. The trajectory showing steep increase over time was associated with higher level of depressive symptoms (M 2.18, 95% CI [2.08, 2.28] vs. 1.99, [1.95, 2.04]). This relationship persisted after adjustments for various risk factors. These triglycerides trajectories accounted for part of the association between high body mass index and depressive symptoms.

CONCLUSION

A pattern of steeply increasing triglyceride levels throughout childhood and adulthood may be associated with increased the risk of depressive symptoms in adulthood. This pattern may also be one link between obesity and depressive symptoms.

Genetic risk factors and markers for Alzheimer's disease and/or depression in the VITA study

OBJECTIVES

In ageing population, both Alzheimer's disease (AD) and depression are common. Significant depressive symptoms are often co-morbid with cognitive impairment and dementia. In this study, we attempted to find various factors and markers for both AD and depression in a longitudinal cohort, the Vienna-Transdanube-Aging (VITA)-study.

METHODS

The VITA-Study consisted of 305 healthy subjects, 174 subjects with depression only, 55 subjects diagnosed with AD only and 72 subjects with depression as well as AD. Associations between AD and/or depression to gene polymorphisms APO E (epsilon4), choline acetyltransferase (ChAT) 4G to A, serotonin-transporter gene promoter-length, dopamine-D4-receptor, ciliary-neurotrophic-factor-null mutation and brain-derived neurotrophic factor (C270T) and to various known factors were analyzed.

RESULTS

AD and depression were significant associated. Significant risk factors found for AD were low education, low folic acid and depressive-symptoms, while for depression were low education and higher nonsteroidal anti-inflammatory drugs (NSAID) consume. Moreover, the ChAT polymorphism associated significant to depression. Gender, education, and ChAT significantly associated with the combination AD and/or depression.

CONCLUSION

Such studies must be conducted cautiously, as co-morbidities and gene-environmental-social influences may sway the results dramatically. We found in the VITA-study significant association between depression and AD and between ChAT polymorphism and depression.