Deep brain stimulation in obsessive-compulsive disorder: Results from meta-analysis.

The aim of this work is to investigate the effectiveness of Deep Brain Stimulation (DBS) in patients with severe Obsessive Compulsive Disorder (OCD) who are resistant to pharmacological treatments, focusing on obsessive compulsive, depressive and anxiety symptoms as well as global function. A systematic review and meta-analysis including 25 studies (without language restrictions) from between 2003 and 2020 was performed. A total of 303 patients were evaluated twice (before and after DBS). After DBS treatment OCD patients with resistance to pharmacological treatments showed a significant improvement of obsessive-compulsive symptoms (25 studies; SMD=2.39; 95% CI, 1.91 to 2.87; P<0.0001), depression (9 studies; SMD= 1.19; 95%CI, 0.84 to 1.54; P<0.0001), anxiety (5 studies; SMD=1.00; 95%CI, 0.32 to 1.69; P=0.004) and functionality (7 studies; SMD=-3.51; 95%CI, -5.00 to -2.02; P=0.005) measured by the standardized scales: Yale Brown Obsessive Compulsive Scale (YBOCS), Hamilton Depression Rating Scale (HAM-D), Hamilton Anxiety Rating Scale (HAM-A) and Global Assessment of Function (GAF). Publication bias were discarded by using funnel plot. The main conclusions of this meta-analysis highlight the statistically significant effectiveness of DBS in patients with severe OCD who are resistant to conventional pharmacological treatments, underlying its role in global functioning apart from obsessive-compulsive symptoms.

Quality of life, anxiety and depressive symptoms in patients with psoriasis: A case-control study.

OBJECTIVE: To compare quality of life (QoL), anxiety and depressive symptoms, alcohol consumption and other correlates between patients with psoriasis and controls; and to identify features of psoriasis associated with lower levels of QoL. METHOD: Case-control study including 70 subjects with moderate-severe psoriasis and 140 controls without psoriasis. All participants answered the Short Form Health Survey (SF-36), with physical and mental component scores of quality of life, and the Hospital Anxiety and Depression Scale (HADS). Among subjects with psoriasis, the Psoriasis Area and Severity Index (PASI) and the Dermatology Life Quality Index (DLQI) were used, respectively, to measure the severity of psoriasis and the impact of psoriasis on the specific quality of life. RESULTS: Compared to controls, patients with psoriasis showed higher HADS depression score and alcohol consumption, and lower QoL. Among subjects with psoriasis, multivariate analysis showed: 1) poorer physical QoL was associated with older age, articular lesions and anxious symptoms, whereas poorer mental QoL was associated with younger age, female sex, genital lesions and depressive symptoms; 2) the higher the severity of psoriasis, the lower the level of QoL and the higher the levels of anxious or depressive symptoms; and 3) female sex and articular or genital location of lesions are linked with higher HADS scores. CONCLUSION: Higher scores in anxiety and depression and lower QoL is common in psoriasis, especially among women and those with genital or articular lesions. Dermatologists should give special attention to this subgroup of persons with psoriasis in order to prevent future psychopathology.

Disordered eating behaviors among Christian and Muslim adolescents in Ceuta, a multicultural town.

Studies on disordered eating behaviors (DEB) in multicultural populations with multiple religious/cultural affiliations are needed in order to clarify the relationship between cultural background and DEB. Therefore, we compared the presence of DEB among Christian and Muslim adolescents who share their school environment, controlling for the effect of body mass index, demographic variables and lifestyle habits. A sample of 493 girls and boys (339 Christian, 138 Muslim) whose mean (±SD) age was 14.8 (±1.7) years completed self-reporting questionnaires and underwent measurements of anthropometric data. Religious/cultural affiliation was defined by self-identification. The dependent variable, DEB was assessed by means of the Eating Disorders Inventory (EDI-2). Muslim girls and boys score higher than Christians on EDI-2 total scores, especially on the perfectionism subscale. Bivariate and multivariate analyses were used to determine the characteristics associated with DEB, which were detected in 24% of participants (19% of Christians and in 35% of Muslims). Among girls, DEB were directly associated with overweight or obesity, the presence of frequent quarrels with parents, academic failure and spending more than 3 h a day watching screen images. Among boys, DEB were directly associated with overweight or obesity and Muslim background; and inversely associated with age and socioeconomic status.

Psychosis management in patients with hiv: case report.

Human immunodeficiency virus (HIV) infection can cause neuropsychiatric disorders such as cognitive impairment, behavioural difficulties or psychiatric symptoms –for instance, mania and psychosis. HIV patients with psychiatric comorbidities need an appropriate treatment which tackles the HIV infection as much as the particular mental symptoms. Here we present the case of a patient suffering from delusions, which turned out to be caused by encephalitis secondary to a previously unknown HIV infection. A review of psychosis in HIV-infected patients is also presented. This review is focused on the epidemiology, etiopathogenesis and clinical presentation of HIV-induced psychosis, as well as the recommended pharmacological treatment (antiretroviral therapy and antipsychotic medication) and the expected treatment response. We also present wide information concerning pharmacological interactions between antiretroviral and antipsychotic medications that we hope will help the clinician to better manage this complex condition.

Temporal sequencing of nicotine dependence and major depressive disorder: A U.S. national study.

Major Depressive Disorder (MDD) and Nicotine dependence (ND) often co-occur. However, little attention has been given to the temporal order between the two disorders. We compared the sociodemographic and clinical characteristics of individuals whose onset of ND preceded (ND-prior) or followed the onset of MDD (MDD-prior). Binary logistic regression models were computed to compare ND-prior (n=546) and MDD-prior (n=801) individuals from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC, n=43,093). We found that MDD-prior were more likely to have a history of suicide attempts and a family history of both depression and antisocial behavior, to have had psychiatric hospitalization, and to have an earlier age of onset of the first depressive episode; but a later age of onset for both daily smoking and ND. On average, MDD-prior individuals showed a significantly longer transition time from daily smoking to ND (15.6±0.6 vs. 6.9±0.4 years, P<0.001). In contrast, ND-prior subjects had a significantly greater proportion of withdrawal symptoms, and of lifetime alcohol use or alcohol use disorder. We conclude that the phenomenology and course of ND and MDD vary significantly, depending on which disorder had earlier onset.

Factors associated with psychological distress or common mental disorders in migrant populations across the world. / Factores asociados a malestar psicológico o trastornos mentales comunes en poblaciones migrantes a lo largo del mundo.

We systematically review factors associated with the presence of psychological distress or common mental disorders in migrant populations. Articles published between January 2000 and December 2014 were reviewed and 85 applying multivariate statistical analysis were selected. Common mental disorders were significantly associated with socio-demographic and psychological characteristics, as observed in large epidemiological studies on general populations. The probability of common mental disorders occurrence differs significantly among migrant groups according to their region of origin. Moreover, traumatic events prior to migration, forced, unplanned, poorly planned or illegal migration, low level of acculturation, living alone or separated from family in the host country, lack of social support, perceived discrimination, and the length of migrants' residence in the host country all increase the likelihood of CMD. In contrast, language proficiency, family reunification, and perceived social support reduce such probability. Factors related with the risk of psychiatric morbidity among migrants should be taken into account to design preventive strategies.

Risk factor assessment and counselling for 12 months reduces metabolic and cardiovascular risk in overweight or obese patients with schizophrenia spectrum disorders: The CRESSOB study.

BACKGROUND: Metabolic syndrome (MS) and cardiovascular risk factors (CRF) have been associated with patients with schizophrenia. The main objective is to assess the evolution of CRF and prevalence of MS for 12 months in a cohort of overweight patients diagnosed with schizophrenia schizophreniform disorder or schizoaffective disorder in which the recommendations for the assessment and control of metabolic and cardiovascular risk were applied. METHODS: The Control of Metabolic and Cardiovascular Risk in Patients with Schizophrenia and Overweight (CRESSOB) study is a 12-month, observational, prospective, open-label, multicentre, naturalistic study including 109 community mental health clinics of Spain. The study included a total of 403 patients, of whom we could collect all variables related to CRF and MS in 366 patients. Of these 366 patients, 286 completed the follow-up, (baseline, months 3, 6 and 12) where they underwent a complete physical examination and a blood test (glucose, cholesterol and triglycerides), they were asked about their health-related habits (smoking, diet and exercise) and they were given a series of recommendations to prevent cardiovascular risk and MS. RESULTS: A total of 403 patients were included, 63% men, mean age (mean; (SD)) 40.5 (10.5) years. After 12 months, the study showed statistically significant decrease in weight (p<0.0001), waist circumference (p<0.0001), BMI (p<0.0001), blood glucose (p=0.0034), total cholesterol (p<0.0001), HDL cholesterol (p=0.02), LDL cholesterol (p=0.0023) and triglycerides (p=0.0005). There was a significant reduction in the percentage of smokers (p=0.0057) and in the risk of heart disease at 10 years (p=0.0353). CONCLUSION: Overweight patients with schizophrenia who receive appropriate medical care, including CRF monitoring and control of health-related habits experience improvements with regard to most CRFs.

Caffeine consumption in a long-term psychiatric hospital: Tobacco smoking may explain in large part the apparent association between schizophrenia and caffeine use.

This study further explores the association between schizophrenia and caffeine use by combining two prior published Spanish samples (250 schizophrenia outpatients and 290 controls from the general population) with two Spanish long-term inpatient samples from the same hospital (145 with schizophrenia and 64 with other severe mental illnesses). The specific aims were to establish whether or not, after controlling for confounders including tobacco smoking, the association between schizophrenia and caffeine is consistent across schizophrenia samples and across different definitions of caffeine use. The frequency of caffeine use in schizophrenia inpatients was not significantly higher than that in non-schizophrenia inpatients (77%, 111/145 vs. 75%, 48/64) or controls but was significantly higher than in schizophrenia outpatients. The frequency of high caffeine users among caffeine users in schizophrenia inpatients was not significantly higher than in non-schizophrenia inpatients (45%, 50/111 vs. 52%, 25/48) or controls, but was significantly lower than in schizophrenia outpatients. Smoking was significantly associated with caffeine use across all samples and definitions. Between 2 and 3% of schizophrenia inpatients, schizophrenia outpatients and non-schizophrenia inpatients showed caffeinism (>700 mg/day in smokers). Several of these smoking patients with caffeinism were also taking other inducers, particularly omeprazole. The lack of consistent association between schizophrenia and caffeine use is surprising when compared with the very consistent association between tobacco smoking and caffeine use across all of our analyses (use and high use in users) and all our samples. The confounding effects of tobacco smoking may explain in large part the apparent association between schizophrenia and caffeine use.

[Prevalence of metabolic syndrome in Spanish patients with schizophrenia and overweight. The CRESSOB Study]. / Prevalencia del síndrome metabólico en pacientes españoles con esquizofrenia y sobrepeso. El estudio CRESSOB.

INTRODUCTION: Metabolic syndrome (MS) (visceral obesity, dyslipidemia, hyperglycemia, and hypertension), has become one of the major public-health challenges worldwide. Patients with schizophrenia are more likely to suffer from MS than the general population. OBJECTIVE: The primary aim of this study was to analyze the prevalence of MS in Spanish patients with schizophrenia and overweight and to compare the best method to calculate the MS prevalence in this population. A secondary aim of the CRESSOB study was to determine whether the presence of the metabolic syndrome (MS) is associated or not with clinical remission of schizophrenia. METHODS: The Control of Metabolic and Cardiovascular Risk in Patients with Schizophrenia and Overweight (CRESSOB) study is a 12-month, prospective, naturalistic study including 110 community mental health clinics selected at random. Each site enrolled four consecutive patients with a diagnosis of schizophrenia, according to DSM-IV TR criteria, and who were overweight (Body Mass Index (BMI) >25 kg/m2). To assess the prevalence of MS we analyzed the baseline results of the CRESSOB study. The National Cholesterol Education Program (NCEP-ATP III), the International Diabetes Federation (IDF) and the American Heart Association/National Heart, Lung, and Blood Institute (AHA/NHLBI) definitions were used to establish the presence of MS. The Positive and Negative Syndrome Scale (PANSS) was used to determine the percentage of patients in remission. Psychosocial functioning was measured by the Global Assessment of Functioning (GAF) scale. RESULTS: A total of 391 patients were enrolled in the study (mean age 40.5 years, 63.8% men). 75.9% of the patients did not meet criteria for remission, using the selected PANSS items. The mean GAF score was 52.7 (Standard Deviation (SD) 15.4). Overall, 59.0% of males and 58.3% of females fulfilled the NCEP-ATP III criteria, 71.1% of males and 65.8% of females fulfilled the IDF criteria and 70.1% of males and 65.1% of females fulfilled the AHA/ NHLBI criteria. The patients who fulfilled remission criteria were younger, had a lower BMI, and a higher GAF score. CONCLUSIONS: MS is highly prevalent in Spanish patients with schizophrenia who are overweight. Given that metabolic syndrome is an important risk factor for cardiovascular disease, these patients should receive appropriate clinical monitoring for this syndrome.

World region of origin and common mental disorders among migrant women in Spain.

Migration can affect the mental health of migrants. This cross-sectional study has two objectives: (1) to compare the prevalence of common mental disorder (CMD) between migrants (n = 458) living in Granada (Spain) and Spanish-born women (n = 448); (2) within migrants, to analyse the associations of world region of origin, other sociodemographic factors and post-migration features with the presence of CMD. Participants answered a questionnaire, including sociodemographic characteristics, post-migration features and CMD that was measured by Kessler K6-scale. Logistic regression analyses showed that CMD (K6 ≥ 13) was significantly higher among migrants than Spaniards. Compared with Spaniards, the odds of CMD were 3.6 [95 % confidence intervals (CI) 2.1­6.0] and 2.9 (CI 1.6­5.3), respectively, for Latin Americans and for Moroccan and other African women. Among migrants, Latin Americans as opposed to the reference group (migrants from other countries), had higher probability of CMD (OR 2.3, CI 1.1­4.9). This study supports the hypothesis that migration leads to mental distress. Consideration of world region of origin may clarify the differences observed in mental health across different migrant groups.

Phosphate levels as a possible state marker in panic disorder: preliminary study of a feasible laboratory measure for routine clinical practice.

OBJECTIVE: Low serum phosphate level is considered one of the metabolic adaptations to the respiratory alkalosis induced by hyperventilation associated with panic disorder. The aim of this study was to assess phosphatemia as a possible state marker for panic disorder. METHODS: Sixteen panic disorder patients underwent clinical assessment with a semi-structured interview, a set of rating scales and the self-rated State and Trait Anxiety Inventory (STAI), as well as extraction of venous blood samples at baseline and after 12 weeks of pharmacological treatment. Ten healthy volunteers of similar sex, age and educational level filled out the STAI and gave blood samples at baseline and 12 weeks later. RESULTS: The median (25th-75th percentiles) of phosphate levels (mg/dl) was 2.68 (2.22-3.18) among patients and 4.13 (3.74-4.70) among healthy volunteers respectively (P < 0.001). Seven (44%) patients and no healthy volunteers presented low serum phosphate (<2.50 mg/dl) at baseline; this patient abnormality was corrected in all cases after successful treatment. At baseline, the age-adjusted correlation between phosphate levels and state-anxiety was -0.66 (P < 0.001) among all 26 participants and -0.51 (P = 0.05) among the 16 panic disorder patients. CONCLUSIONS: Measurement of phosphate levels could be easily introduced into clinical practice as a possible marker for chronic hyperventilation in panic disorder, although further investigations with larger sample sizes are necessary to characterize panic disorder patients with low versus normal phosphate levels.

Temporal sequencing of nicotine dependence and bipolar disorder in the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC).

Bipolar disorder (BD) and nicotine dependence (ND) often co-occur. However, the mechanisms underlying this association remain unclear. We aimed to examine, for the first time in a national and representative sample, the magnitude and direction of the temporal relationship between BD and ND; and to compare, among individuals with lifetime ND and BD, the sociodemographic and clinical characteristics of individuals whose onset of ND preceded the onset of BD (ND-prior) with those whose onset of ND followed the onset of BD (BD-prior). The sample included individuals with lifetime BD type I or ND (n = 7958) from the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC, n = 43093). Survival analyses and logistic regression models were computed to study the temporal association between ND and BD, and to compare ND-prior (n = 135) and BD-prior (n = 386) individuals. We found that ND predicted the onset of BD and BD also predicted the onset of ND. Furthermore, the risk of developing one disorder following the other one was greatest early in the course of illness. Most individuals with lifetime ND and BD were BD-prior (72.6%). BD-prior individuals had an earlier onset of BD and a higher number of manic episodes. By contrast, ND-prior individuals had an earlier onset of both daily smoking and ND, and an increased prevalence of alcohol use disorder. In conclusion, ND and BD predict the development of each other. The phenomenology and course of ND and BD varied significantly depending on which disorder had earlier onset.

Predictors of quit attempts and successful quit attempts in a nationally representative sample of smokers.

Although most current smokers report that they would like to quit, most quit attempts fail suggesting that predictors of quitting attempts may differ from those of successful attempts. We examined sociodemographic and clinical predictors of quit attempts and successful quit attempts in a nationally representative sample of US adults. Data was collected in 2001-2002 (Wave 1) and 2004-2005 (Wave 2). Almost 40% of individuals who had not previously attempted to quit, tried to quit over the next three years; only 4.6% of those who tried had succeeded at the time of the evaluation. Hispanics, Asians, individuals with high income, and those with college education were less likely to attempt to quit, whereas those with daily nicotine use, younger age at first use and most symptoms of dependence were more likely to do so. Having an educational level below high school and older age at first nicotine use were predictors of successful quitting. Despite relatively high rates of quit attempts, rates of success are extremely low, indicating a gap between the public health need of decreasing tobacco use, and existing means to achieve it. Although there is a need to encourage people to quit tobacco, there may be an equally large need to develop more effective interventions that increase the rate of successful quit attempts.

Adherence to the Mediterranean dietary pattern and personality in patients attending a primary health center.

Personality influences lifestyle behaviors, and particularly dietary behavior. The possible association of personality with adherence to the Mediterranean diet pattern (MDP) has not been reported. The objective of this study was to analyze the possible association of personality traits with adherence to the MDP, controlling for sociodemographic variables, presence of chronic illnesses, minor psychiatric morbidity, body mass index (BMI), daily smoking, and physical activity. This cross-sectional study included 206 patients, age 18 to 65 years, recruited at a primary health service in Granada, Spain, during 2007 to 2008. The participants answered a questionnaire, including sociodemographic characteristics, data on personality, and MDP. Personality was measured by the Temperament and Character Inventory (TCI-125). Adherence to MDP was measured using the validated 14-point Mediterranean Diet Adherence Screener (MEDAS). MEDAS score was directly associated with the character dimension of self-directedness, age, and minor psychiatric morbidity score; and inversely with marital status (widowed, separated, or divorced) and BMI. Because highly self-directed individuals may respond better to diet advice, consideration of personality may prove helpful in the design of interventions to enhance the adherence to MDP. To improve the adherence to MDP in interventions with patients with low self-directedness, more intensive professional support and counseling with tailored messages about the health benefits of MDP may be indicated.

Stability of sex differences by diagnosis in psychiatric hospitalizations.

We examined sex differences in the distribution of psychiatric diagnoses among hospitalized patients, controlling for socio-demographic variables. The sample included 1865 psychiatric inpatients consecutively admitted during a 9-year period. The finding of a higher proportion of men among patients hospitalized for schizophrenia or substance use disorder and a higher proportion of women among those admitted for affective disorders, including bipolar disorder, was stable over time. A better understanding of these differences may help to establish more effective treatment strategies.

Factors associated with frequent psychiatric admissions in a general hospital in Spain.

OBJECTIVES: To identify demographic or clinical factors associated with frequent admissions in a sample of patients admitted to an acute psychiatric hospitalization unit, controlling for potentially confounding factors. METHODS: Socio-demographic variables, diagnosis, and the legal status, date and length of admission were collected for 1,722 consecutively admitted psychiatric patients during a period of up to eight years (1998-2005). Frequently admitted patients were defined as undergoing one or more admissions per year on average. RESULTS: After controlling for potential confounding factors, logistic regression showed that being a frequently admitted patient was significantly associated with diagnoses of schizoaffective disorder, personality disorder or schizophrenia; an involuntary commitment at first admission; and younger age. CONCLUSIONS: Factors associated with frequently admitted patients should be identified in order to establish more effective strategies for preventing relapse.

Winter birth excess in schizophrenia and in non-schizophrenic psychosis: sex and birth-cohort differences.

OBJECTIVE: Despite the fact that association between winter birth excess and schizophrenia in the northern Hemisphere is well established, possible sex or birth-cohort differences in this winter birth excess remain unclear. We aimed to evaluate sex and birth-cohort differences in the seasonal birth distribution of patients with schizophrenia or non-schizophrenic psychosis. METHOD: The sample included 321 ICD-10 schizophrenia and 294 non-schizophrenic psychosis patients consecutively admitted into a psychiatric hospitalization unit in Granada, southern Spain, during a nine-year period (1998-2006). The distribution of births among the general population born over the same period as the patients was calculated. RESULTS: Among schizophrenia males (n=258), it was possible to demonstrate that the observed proportion of winter birth (December, January or February) was significantly higher than expected. Among schizophrenia females (n=63), although proportions were as in males and the effect size of the difference between observed and expected winter births was not lower than for men, only a statistical trend could be demonstrated. Among patients with non-schizophrenic psychosis, the observed proportion of winter birth was significantly higher than expected in women, but not in men. The sex-adjusted proportion of winter birth among schizophrenia patients born in the 1940's (a time period characterized by poor economy and widespread food restrictions because of the Spanish post-civil-war period) was significantly higher than among those born later; a difference that does not occur among patients with a non-schizophrenic psychosis. CONCLUSIONS: Among schizophrenia patients born in winter there appear to be slight sex-differences and strong birth-cohort differences, possibly due to epidemiological factors such as poverty or maternal nutritional deprivation. Epidemiological findings related to winter birth excess among patients with schizophrenia must be identified in longitudinal studies.

Nicotine dependence vs. daily smoking as a meaningful variable: implications for clinical and epidemiological psychiatric studies.

OBJECTIVE: As an indication of potential psychopathology, our aim was to compare, in a non-psychiatric sample, the variables associated to daily smoking with those associated to nicotine dependence. We also compared dependent and non-dependent smokers on these variables and on the age of onset of daily smoking (AODS). METHOD: A sample of 290 persons aged 18 or older, recruited in a family medical clinic, were interviewed to inquire about their tobacco, caffeine, alcohol, and illegal drugs consumption, and on their practice of physical exercise. Psychiatric morbidity was assessed with the General Health Questionnaire (GHQ-28) and defined by a score>6. They also were questioned on their use of psychotropic medication and previous suicide attempt. The smokers answered the Fagerström Test for Nicotine Dependence (FTND) and the question on their age of onset of daily smoking (AODS). RESULTS: In comparison with non-dependent smoking, nicotine dependence was associated with current use of psychotropic medication, psychiatric morbidity, previous suicide attempt, and earlier AODS. Logistic regression analyses showed that nicotine dependence was associated with antecedents of suicide attempt and primary or lower education as well as with high caffeine use and the regular use of illegal drugs; in contrast, daily smoking showed a significant association with high caffeine use, the regular use of illegal drugs and lack of physical exercise. CONCLUSIONS: In terms of psychopathology or behavioral disturbance-particularly attempting suicide-nicotine dependence adds significant information as opposed to the simple daily smoking, with important implications in clinical and epidemiological psychiatric studies.

Subjective effects and the main reason for smoking in outpatients with schizophrenia: a case-control study.

This study examines in daily smokers (1) subjective effects and main reason for smoking after controlling for nicotine dependence level in 100 controls and 173 patients with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, schizophrenia and (2) the association of specific subjective effects and schizophrenia symptoms. The subjective effects and the main reason for smoking were studied using a questionnaire and the schizophrenia symptoms with the Positive and Negative Syndrome Scale. Proportions were compared by odds ratios controlling for the effects of sex, age, education, and level of nicotine dependence by logistic regression. Schizophrenia was strongly associated with subjective effects of cheerfulness, agility, alertness, concentration, and calmness. In patients with schizophrenia, a cheerfulness effect was associated with higher depressive symptoms; a calming effect, with higher anxiety symptoms; and a sociability effect, with lower negative symptoms. Compared with controls, desire for calmness as the main reason for smoking was more frequent in patients with schizophrenia. These survey data call for confirmation through experimental studies and may help in the design of more focused smoking cessation programs for these patients.

Fewer but heavier caffeine consumers in schizophrenia: a case-control study.

According to the literature, there is an association between schizophrenia and caffeine consumption, but it is not clear whether schizophrenia is associated with either higher prevalence of daily caffeine intake or the amount consumed. In this study we compared our previously published schizophrenia patients (n=250) with a control sample (n=290) after controlling for demographic variables and tobacco and alcohol consumption. Current caffeine intake was less frequent in schizophrenia patients (59%, 147/250) than in controls (70%, 204/290). In the multivariate analyses, caffeine intake was less frequent at an older age and in schizophrenia patients, and more frequent in smokers and alcohol users. Among caffeine consumers, heavy caffeine intake (> or =200 mg/day) was significantly associated with schizophrenia (64%, 94/147 in schizophrenia versus 36%, 73/204 in controls), as well as older age and smoking. Daily amount of caffeine intake and smoked cigarettes correlated significantly in the schizophrenia group but not in the control group; the correlation of caffeine intake with nicotine dependence was low and non-significant in both groups. The association between current smoking and heavy caffeine intake may be partly explained by a pharmacokinetic effect: tobacco smoke compounds induce caffeine metabolism by the cytochrome P450 1A2. Although schizophrenia by itself may be associated with heavy caffeine intake in caffeine users, part of this association was explained by the association between schizophrenia and smoking. The relationship between caffeine and alcohol intake appeared to be more complex; alcohol and caffeine use were significantly associated, but within caffeine users alcohol was associated with less frequent heavy caffeine consumption among smokers. In future studies, the measurement of plasma caffeine levels will help both to better define heavy caffeine intake and to control for smoking pharmacokinetic effects.