J. Elisabeth Wells

Prevalence and Correlates of Bipolar Spectrum Disorder in the World Mental Health Survey Initiative

CONTEXT There is limited information on the prevalence and correlates of bipolar spectrum disorder in international population-based studies using common methods. OBJECTIVES To describe the prevalence, impact, patterns of comorbidity, and patterns of service utilization for bipolar spectrum disorder (BPS) in the World Health Organization World Mental Health Survey Initiative. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional, face-to-face, household surveys of 61,392 community adults in 11 countries in the Americas, Europe, and Asia assessed with the World Mental Health version of the World Health Organization Composite International Diagnostic Interview, version 3.0, a fully structured, lay-administered psychiatric diagnostic interview. MAIN OUTCOME MEASURES Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) disorders, severity, and treatment. RESULTS The aggregate lifetime prevalences were 0.6% for bipolar type I disorder (BP-I), 0.4% for BP-II, 1.4% for subthreshold BP, and 2.4% for BPS. Twelve-month prevalences were 0.4% for BP-I, 0.3% for BP-II, 0.8% for subthreshold BP, and 1.5% for BPS. Severity of both manic and depressive symptoms as well as suicidal behavior increased monotonically from subthreshold BP to BP-I. By contrast, role impairment was similar across BP subtypes. Symptom severity was greater for depressive episodes than manic episodes, with approximately 74.0% of respondents with depression and 50.9% of respondents with mania reporting severe role impairment. Three-quarters of those with BPS met criteria for at least 1 other disorder, with anxiety disorders (particularly panic attacks) being the most common comorbid condition. Less than half of those with lifetime BPS received mental health treatment, particularly in low-income countries, where only 25.2% reported contact with the mental health system. CONCLUSIONS Despite cross-site variation in the prevalence rates of BPS, the severity, impact, and patterns of comorbidity were remarkably similar internationally. The uniform increases in clinical correlates, suicidal behavior, and comorbidity across each diagnostic category provide evidence for the validity of the concept of BPS. Treatment needs for BPS are often unmet, particularly in low-income countries.

Toward a global view of alcohol, tobacco, cannabis, and cocaine use: findings from the WHO World Mental Health Surveys

Background Alcohol, tobacco, and illegal drug use cause considerable morbidity and mortality, but good cross-national epidemiological data are limited. This paper describes such data from the first 17 countries participating in the World Health Organizations (WHOs) World Mental Health (WMH) Survey Initiative. Methods and Findings Household surveys with a combined sample size of 85,052 were carried out in the Americas (Colombia, Mexico, United States), Europe (Belgium, France, Germany, Italy, Netherlands, Spain, Ukraine), Middle East and Africa (Israel, Lebanon, Nigeria, South Africa), Asia (Japan, Peoples Republic of China), and Oceania (New Zealand). The WHO Composite International Diagnostic Interview (CIDI) was used to assess the prevalence and correlates of a wide variety of mental and substance disorders. This paper focuses on lifetime use and age of initiation of tobacco, alcohol, cannabis, and cocaine. Alcohol had been used by most in the Americas, Europe, Japan, and New Zealand, with smaller proportions in the Middle East, Africa, and China. Cannabis use in the US and New Zealand (both 42%) was far higher than in any other country. The US was also an outlier in cocaine use (16%). Males were more likely than females to have used drugs; and a sex–cohort interaction was observed, whereby not only were younger cohorts more likely to use all drugs, but the male–female gap was closing in more recent cohorts. The period of risk for drug initiation also appears to be lengthening longer into adulthood among more recent cohorts. Associations with sociodemographic variables were consistent across countries, as were the curves of incidence of lifetime use. Conclusions Globally, drug use is not distributed evenly and is not simply related to drug policy, since countries with stringent user-level illegal drug policies did not have lower levels of use than countries with liberal ones. Sex differences were consistently documented, but are decreasing in more recent cohorts, who also have higher levels of illegal drug use and extensions in the period of risk for initiation.

Christchurch Psychiatric Epidemiology Study, Part I: Methodology and Lifetime Prevalence for Specific Psychiatric Disorders

In 1986 the Christchurch Psychiatric Epidemiology Study obtained interviews with a probability sample of 1498 adults aged 18 to 64 years. The Diagnostic Interview Schedule (DIS) was used to enable DSM-III diagnoses to be made. This paper describes the methodology of the study and reports the lifetime prevalence of specific psychiatric disorders. The highest lifetime prevalences found were for generalised anxiety (31%), alcohol abuseldependence (19%) and major depressive episode (13%). Men had higher rates of substance abuse whereas women had higher rates of affective disorders and most anxiety disorders. Compared with results from the Epidemiologic Catchment Area Program, Puerto Rico and Edmonton, Christchurch has the highest rates for major depression and is among the highest for alcohol abuse/dependence.

Effect of enalapril on ventricular arrhythmias in congestive heart failure

Twenty-four-hour Holter electrocardiographic recordings were used to measure the effects of a converting-enzyme inhibitor, enalapril, given for 12 weeks, on the frequency of cardiac arrhythmias in 10 patients with congestive heart failure (New York Heart Association functional class II to III) receiving maintenance therapy with digoxin and furosemide. Nine patients were given placebo, and both study groups were conducted in a double-blind, parallel manner. The placebo group had no change in the frequency of arrhythmias, whereas enalapril-treated patients showed a significant decrease in the frequency of premature ventricular complexes, ventricular couplets and ventricular tachycardia. A minor, nonsignificant reduction in atrial premature complexes was seen in patients who received enalapril. Compared with placebo patients, those who received enalapril had an increase in plasma potassium levels of 0.33 mmol/liter, a decrease in plasma digoxin, and decreases in pulmonary artery wedge, mean pulmonary artery and right atrial pressures. However, none of these indexes were correlated with the concomitant decline in cardiac arrhythmias. It is concluded that enalapril reduces the frequency of ventricular arrhythmias in congestive heart failure, although the underlying mechanisms are not known.

Christchurch Psychiatric Epidemiology Study, Part II: Six Month and Other Period Prevalences of Specific Psychiatric Disorders

The Christchurch Psychiatric Epidemiology Study determined the occurrence (over 2 weeks, 1 month, 6 months, 12 months and life-time) of a number of specific DWDSM-III psychiatric diagnoses in the Christchurch urban area. Data were collected on 1498 randomly selected adults, aged between 18 and 64 years. The Diagnostic interview Schedule (DIS) was used to collect information to make a DSM-III diagnosis. The six month prevalence rates of disorder are presented and compared with available results from the NlMH Epidemiological Catchment Area Program, Puerto Rico and Edmonton. Other period prevalences for the total sample are also presented. Christchurch is shown to have higher six month prevalence rates for major depression and alcohol abuse/dependence than other sites which have utilised the DIS in community surveys.

Prevalence, interference with life and severity of 12 month DSM-IV disorders in Te Rau Hinengaro: The New Zealand Mental Health Survey

OBJECTIVE To estimate the 12 month prevalence of DSM-IV disorders in New Zealand, and associated interference with life and severity. METHOD A nationally representative face-to-face household survey carried out in 2003-2004. A fully structured diagnostic interview, the World Health Organization World Mental Health Survey Initiative version of the Composite International Diagnostic Interview (CIDI 3.0) was used. There were 12,992 completed interviews from participants aged 16 years and over. The overall response rate was 73.3%. In this paper the outcomes reported are 12 month prevalence, interference with life and severity for individual disorders. RESULTS The prevalence of any disorder in the past 12 months was 20.7%. The prevalences for disorder groups were: anxiety disorders 14.8%, mood disorders 7.9%, substance use disorders 3.5%, eating disorders 0.5%. The highest prevalences for individual disorders were for specific phobia (7.3%), major depressive disorder (5.7%) and social phobia (5.1%). Interference with life was higher for mood disorders than for anxiety disorders. Drug dependence, bipolar disorder and dysthymia had the highest proportion of severe cases (over 50%), when severity was assessed over the disorder itself and all comorbid disorders. Overall, only 31.7% of cases were classified as mild with 45.6% moderate and 22.7% serious. CONCLUSIONS Compared with other World Mental Health survey sites New Zealand has relatively high prevalences, although almost always a little lower than for the US. For all disorders, except specific phobia, interference with life was reported to be moderate, on average, which has lead to less than a third of cases being classified as mild. Most people who have ever met full DSM-IV criteria, including the impairment criterion, and who experience symptoms or an episode in the past 12 months find that their disorders impact on their lives to a non-trivial extent.

Lifetime prevalence and projected lifetime risk of DSM-IV disorders in Te Rau Hinengaro: The New Zealand Mental Health Survey

Objective: To estimate the lifetime prevalence and projected lifetime risk at age 75 years of DSM-IV disorders in New Zealand. Method: A nationwide face-to-face household survey carried out in 2003–2004. A fully structured diagnostic interview, the World Health Organization Composite International Diagnostic Interview (CIDI 3.0), was used. There were 12 992 completed interviews from participants aged 16 years and over. The overall response rate was 73.3%. In this paper, the outcomes reported are lifetime prevalence and projected lifetime risk at age 75 years. Results: The lifetime prevalence of any disorder was 39.5%. The lifetime prevalences for disorder groups were: anxiety disorders, 24.9%; mood disorders, 20.2%; substance use disorders, 12.3%; and eating disorders, 1.7%. The prevalences for all disorders were higher in the younger age groups. Females had higher prevalences of anxiety, mood and eating disorders compared with males; males had higher prevalences of substance use disorders. The estimated projected lifetime risk of any disorder at age 75 years was 46.6% with the median age of onset being 18 years. Adjustment for age, sex, education and household income did not remove all differences between Māori and the composite other ethnic group in the risk of disorder (hazard ratio = 1.1–1.4). After adjustment, hazard ratios for Pacific people ranged from 0.8 to 2.5. Conclusions: These results confirm those of other studies: mental disorders are relatively common and tend to have early onset. Females are more likely to experience anxiety, mood and eating disorders than males, who experience more substance use disorders. Adjustment for socioeconomic factors and demography does not explain all ethnic differences, although remaining differences are small relative to cohort and even sex differences.

BLOOD-PRESSURE RESPONSE TO MODERATE SODIUM RESTRICTION AND TO POTASSIUM SUPPLEMENTATION IN MILD ESSENTIAL HYPERTENSION

To determine whether moderate restriction of dietary sodium content or supplementation of potassium intake reduces blood-pressure in patients with mild essential hypertension, twelve patients were put on three different diets--a control diet (180 mmol sodium/day), a sodium restricted diet (80 mmol/day). Each diet was taken for at least 4 weeks and the sequence of the regimens was randomised. At the completion of each regimen intra-arterial pressure was recorded continuously, and vasoactive hormones were measured hourly, for 24 h, under standardised conditions, in hospital. Compared with the control diet, sodium restriction was associated with lower blood-pressure readings in seven patients, higher levels in five, and an overall reduction in mean pressures of only 4.0/3.0 mm Hg (not significant). Individual differences in blood-pressure between these two diets correlated closely with concomitant differences in plasma renin activity (r = 0.75). Potassium supplementation also resulted in variable changes in arterial pressure, and the mean difference in pressure recordings (0.1/0.8 mm Hg) was insignificant. The results show that moderate restriction of sodium intake or supplementation of dietary potassium has variable effects on arterial pressure in individuals with mild essential hypertension, and that overall the blood-pressure changes induced are very small. Responsiveness of the renin-angiotensin system may limit the fall in blood-pressure induced by sodium restriction.

How accurate is recall of key symptoms of depression? A comparison of recall and longitudinal reports.

BACKGROUND Assessment of lifetime major depression is usually made from a single interview. Most previous studies have investigated reliability. Comparison of recall of key symptoms and longitudinal reports shows the accuracy of recall, not just reliability. METHOD At age 25, 1003 members of the Christchurch Health and Development Study cohort were asked to recall key symptoms of depression (sadness, loss of interest) up to age 21. This recall was compared with longitudinal reports at ages 15, 16, 18 and 21 years. Diagnosis was by DSM-III-R and DSM-IV criteria. RESULTS Only 4% of those without previous reports recalled key symptoms. Of those with a diagnosis of depression up to age 21, 44% recalled a key symptom. Measures of severity of an episode (number of symptoms, impairment, duration, suicidally) and chronicity (years with a diagnosis, years with suicidal ideation) all strongly predicted recall. Current key symptoms increased recall, even after taking account of severity and chronicity. Being female and receiving treatment also predicted recall, although odds ratios were reduced to 1.6-1.7 when all other predictors were included. Comparison of risk factors for key symptoms showed similar results from longitudinal reports and recall. Sexual abuse, neuroticism, lack of parental attachment, gender, physical abuse and maternal depression were major risk factors in both sets of analyses. CONCLUSIONS Forgetting of prior episodes of depression was common. Severity, chronicity, current depression, gender and treatment predicted recall. Lifetime prevalence based on recall will be markedly underestimated but the identification of major risk factors may be relatively little impaired.

Te Rau Hinengaro: The New Zealand Mental Health Survey: overview of methods and findings

OBJECTIVE To estimate the prevalence and severity of anxiety, mood, substance and eating disorders in New Zealand, and associated disability and treatment. METHOD A nationwide face-to-face household survey of residents aged 16 years and over was undertaken between 2003 and 2004. Lay interviewers administered a computerized fully structured diagnostic interview, the World Health Organization World Mental Health Survey Initiative version of the Composite International Diagnostic Interview. Oversampling doubled the number of Māori and quadrupled the number of Pacific people. The outcomes reported are demographics, period prevalences, 12 month severity and correlates of disorder, and contact with the health sector, within the past 12 months. RESULTS The response rate was 73.3%. There were 12,992 participants (2,595 Māori and 2,236 Pacific people). Period prevalences were as follows: 39.5% had met criteria for a DSM-IV mental disorder at any time in their life before interview, 20.7% had experienced disorder within the past 12 months and 11.6% within the past month. In the past 12 months, 4.7% of the population experienced serious disorder, 9.4% moderate disorder and 6.6% mild disorder. A visit for mental health problems was made to the health-care sector in the past 12 months by 58.0% of those with serious disorder, 36.5% with moderate disorder, 18.5% with mild disorder and 5.7% of those not diagnosed with a disorder. The prevalence of disorder and of serious disorder was higher for younger people and people with less education or lower household income. In contrast, these correlates had little relationship to treatment contact, after adjustment for severity. Compared with the composite Others group, Māori and Pacific people had higher prevalences of disorder, unadjusted for sociodemographic correlates, and were less likely to make treatment contact, in relation to need. CONCLUSIONS Mental disorder is common in New Zealand. Many people with current disorder are not receiving treatment, even among those with serious disorder.