Biomedical subjects

Paul Waraich

Publications and source records attributed to Paul Waraich.

9 recordsLinked to original sources

PubMed2006

Increase in schizophrenia incidence rates: findings in a Canadian cohort born 1975-1985.

BACKGROUND: Results from previous studies on the incidence rates for schizophrenia are inconsistent, with some showing a declining rate [e.g., Suvisaari et al. (1999) Arch Gen Psychiatry 56:733-740] and others showing an increasing rate [e.g., Boydell et al. (2003) Br J Psychiatry 182:45-49]. OBJECTIVE: This study examines (1) whether incidence rates are changing, (2) relationships amongst changing incidence rates and age, period and cohort effects, and (3) the impact of rate changes on rate projections. DESIGN: A care-based cohort study carried out in British Columbia, Canada, 1989-1998. Bayesian statistical analyses were used to estimate rates and describe secular effects. Classical tests of significance were used to assess the relative importance of age, period and cohort effects. RESULTS: Between 1989 and 1998, median rates per 100,000 persons changed from 77.1 (90% credible interval (CI): 42.1-137.7) to 89.9 (90% CI: 80.1-100.1) in females, and from 66.6 (90% CI: 38.8-113.3) to 119.6 (90% CI: 107.4-132.4) in males. Age effects were active for both males and females. Period and cohort effects were stronger for males than females. CONCLUSIONS: In contrast to most previous studies, we found an increasing incidence of schizophrenia. Precise projections of schizophrenia incidence beyond 5 years require large sample sizes over prolonged periods of follow-up.

Adolescent↗

PubMed2006

Prevalence and incidence studies of anxiety disorders: a systematic review of the literature.

OBJECTIVE: To present the results of a systematic review of literature published between 1980 and 2004 reporting findings of the prevalence and incidence of anxiety disorders in the general population. METHOD: A literature search of epidemiologic studies of anxiety disorders was conducted, using Medline and HealthSTAR databases, canvassing English-language publications. Eligible publications were restricted to studies that examined age ranges covering the adult population. A set of predetermined inclusion and exclusion criteria were used to identify relevant studies. Prevalence and incidence data were extracted and analyzed for heterogeneity. RESULTS: A total of 41 prevalence and 5 incidence studies met eligibility criteria. We found heterogeneity across 1-year and lifetime prevalence rates of all anxiety disorder categories. Pooled 1-year and lifetime prevalence rates for total anxiety disorders were 10.6% and 16.6%. Pooled rates for individual disorders varied widely. Women had generally higher prevalence rates across all anxiety disorder categories, compared with men, but the magnitude of this difference varied. CONCLUSION: The international prevalence of anxiety disorders varies greatly between published epidemiologic reports. The variability associated with all anxiety disorders is considerably smaller than the variability associated with individual disorders. Women report higher rates of anxiety disorders than men. Several factors were found to be associated with heterogeneity among rates, including diagnostic criteria, diagnostic instrument, sample size, country studied, and response rate.

Anxiety Disorders↗

PubMed2005

Modern antipsychotic drugs: a critical overview.

Conventional antipsychotic drugs, used for a half century to treat a range of major psychiatric disorders, are being replaced in clinical practice by modern "atypical" antipsychotics, including aripiprazole, clozapine, olanzapine, quetiapine, risperidone and ziprasidone among others. As a class, the newer drugs have been promoted as being broadly clinically superior, but the evidence for this is problematic. In this brief critical overview, we consider the pharmacology, therapeutic effectiveness, tolerability, adverse effects and costs of individual modern agents versus older antipsychotic drugs. Because of typically minor differences between agents in clinical effectiveness and tolerability, and because of growing concerns about potential adverse long-term health consequences of some modern agents, it is reasonable to consider both older and newer drugs for clinical use, and it is important to inform patients of relative benefits, risks and costs of specific choices.

Antipsychotic Agents↗

PubMed2004

Is remission of depressive symptoms in primary care a realistic goal? A meta-analysis.

BACKGROUND: A primary goal of acute treatment for depression is clinical remission of symptoms. Most meta-analyses of remission rates involve randomized controlled trials (RCTs) using patients from psychiatric settings, but most depressed patients are treated in primary care. The goal of this study was to determine remission rates obtained in RCTs of treatment interventions for Major Depressive Disorder (MDD) conducted in primary care settings. METHODS: Potentially relevant studies were identified using computerized and manual search strategies up to May 2003. Criteria for inclusion included published RCTs with a clear definition of remission using established outcome measures. RESULTS: A total of 13 studies (N = 3202 patients) meeting inclusion criteria were identified. Overall remission rates for active interventions ranged between 50% and 67%, compared to 32% for pill placebo conditions and 35% for usual care conditions. CONCLUSIONS: Remission rates in primary care studies of depression are at least as high as for those in psychiatric settings. It is a realistic goal for family physicians to target remission of symptoms as an optimal outcome for treatment of depression.

Antidepressive Agents↗

PubMed2004

Prevalence and incidence studies of mood disorders: a systematic review of the literature.

OBJECTIVE: To present the results of a systematic review of literature published between January 1, 1980, and December 31, 2000, that reports findings on the prevalence and incidence of mood disorders in both general population and primary care settings. METHOD: We conducted a literature search of epidemiologic studies of mood disorders, using Medline and HealthSTAR databases and canvassing English-language publications. Eligible publications were restricted to studies that examined subjects aged at least 15 years and over. We used a set of predetermined inclusion and exclusion criteria to identify relevant studies. We extracted and analyzed prevalence and incidence data for heterogeneity. RESULTS: Of general population studies, a total of 18 prevalence and 5 incidence studies met eligibility criteria. We found heterogeneity across 1-year and lifetime prevalence of major depressive disorder (MDD), dysthymic disorder and bipolar I disorder. The corresponding pooled rates for 1-year prevalence were 4.1 per 100, 2.0 per 100, and 0.72 per 100, respectively. For lifetime prevalence, the corresponding pooled rates were 6.7 per 100, 3.6 per 100, and 0. per 100, respectively. Significant variation was observed among 1-year incidence rates of MDD, with a correspond ing pooled rate of 2.9 per 100. CONCLUSIONS: The prevalence of mood disorders reported in high-quality studies is generally lower than rates commonly reported in the general psychiatric literature. When controlled for common methodological confounds, variation in prevalence rates persists across studies and deserves continued study. Methodological variation among studies that have examined the prevalence of depression in primary health care services is so large that comparative analyses cannot be achieved.

Analysis of Variance↗

PubMed2004

Prevalence studies of substance-related disorders: a systematic review of the literature.

OBJECTIVE: To present the results of a systematic review of literature published between January 1, 1980, and December 31, 2000, that reports epidemiologic estimates of substance-related disorders. METHOD: We conducted a literature search of substance-related epidemiologic studies, using medline and HealthSTAR databases and applying a set of predetermined inclusion and exclusion criteria to identify relevant studies. We extracted and analyzed prevalence and incidence data for heterogeneity. RESULTS: A total of 19 prevalence studies of substance-related disorders met inclusion criteria for this review. Heterogeneity analyses revealed significant variability across 1-year and lifetime prevalence of both alcohol and other substance use disorders. The corresponding 1-year and lifetime pooled rates were 6.6 per 100 and 13.2 per 100, respectively, for alcohol use disorders and 2.4 per 100 and 2.4 per 100, respectively, for other substance use disorders. We observed variability among countries and also among regions within the same country. In contrast to other drug problems, alcohol use disorders were substantially more common, were more likely to occur among male subjects, and were more likely to be associated with abuse symptoms. For other drugs, dependence was consistently more prevalent than abuse. CONCLUSIONS: Studies using rigorous and comparable methodologies report significant variability in rates of alcohol and other substance use disorders. These data suggest that different policies and regional practices are associated with variability in rates of disorders. Policy-makers and health planners require regular, regionally sensitive estimates of prevalence rates to respond effectively to unique patterns of need in their constituencies.

Adolescent↗

PubMed2003

Using administrative data to analyze the prevalence and distribution of schizophrenic disorders.

OBJECTIVE: In order to effectively plan and implement psychiatric services, a clear estimate of the prevalence and distribution of the population in need is required. The authors examined the use of administrative data as a means of estimating the prevalence and distribution of schizophrenic disorders. METHODS: Administrative health services data for residents of the Canadian province of British Columbia in the age range 15 to 65 years (total population in 1997-1998 of 2,703,588) were examined over a three-year period. Potential cases of schizophrenic disorder were identified on the basis of the presence of a diagnostic code of 295 in one or more of three databases. One-year prevalence rates were estimated for each of the province's geographic regions, and associations with low income and unemployment were examined. RESULTS: One-year prevalence rate estimates were.45 cases per 100 population in 1996-1997 and 1997-1998 and.42 cases per 100 in 1998-1999. The prevalence estimates of all 88 local health areas in the province were consistent across the three-year period; Pearson correlations were determined to be approximately.9. One-year contact prevalence rates for schizophrenic disorders were significantly correlated in all three years to the percentage of persons with low income in the individual geographic regions but were not correlated with unemployment rates. CONCLUSIONS: In areas with well-developed health services, analyses of administrative data appear to provide cost-effective means of examining the prevalence and distribution of schizophrenic disorders.

Adolescent↗

PubMed2002

Enhanced tactile encoding and memory recognition in congenital blindness.

Several behavioural studies have shown that early-blind persons possess superior tactile skills. Since neurophysiological data show that early-blind persons recruit visual as well as somatosensory cortex to carry out tactile processing (cross-modal plasticity), blind persons' sharper tactile skills may be related to cortical re-organisation resulting from loss of vision early in their life. To examine the nature of blind individuals' tactile superiority and its implications for cross-modal plasticity, we compared the tactile performance of congenitally totally blind, low-vision and sighted children on raised-line picture identification test and re-test, assessing effects of task familiarity, exploratory strategy and memory recognition. What distinguished the blind from the other children was higher memory recognition and higher tactile encoding associated with efficient exploration. These results suggest that enhanced perceptual encoding and recognition memory may be two cognitive correlates of cross-modal plasticity in congenital blindness.

Analysis of Variance↗

PubMed2002

Prevalence and incidence studies of schizophrenic disorders: a systematic review of the literature.

OBJECTIVE: To present the results of a systematic review of the literature published between January 1, 1980, and December 31, 2000, that reports findings on the prevalence and incidence of schizophrenia and related disorders. METHOD: We conducted a literature search of schizophrenia-related epidemiological studies, using Medline and HealthSTAR databases and canvassing English-language publications. We used a set of predetermined inclusion-exclusion criteria to identify relevant studies. Eligible publications were restricted to age ranges of 18 years and over for prevalence studies and 15 years and over for incidence studies. Prevalence and incidence data were extracted and analyzed for heterogeneity. RESULTS: A total of 18 prevalence and 8 incidence studies met eligibility criteria for the review. Heterogeneity analysis revealed significant differences across 1-year and lifetime prevalence and 1-year incidence of schizophrenia. The corresponding pooled rates were: 0.34 per 100, 0.55 per 100, and 11.1 per 100,000, respectively; the variation in rates between studies was generally between 2- and 5-fold. CONCLUSIONS: Although we restricted this review to studies using rigorous and relatively homogeneous methods, there remains significant heterogeneity of prevalence and incidence rates. This strengthens support for the hypothesis that there is real variation in the distribution of schizophrenia around the world. Health planners need to have local data on schizophrenia rates to improve the accuracy of their interventions, while clinicians and researchers need to continue to investigate the etiology of this variation.

Humans↗