Psychiatric co-morbidity is often inadequately controlled for in studies on cognitive functioning in depression. Our recent study established no major deficits in cognition among young adults with a history of pure unipolar depression. The present study extends our previous work by examining the effects of psychiatric co-morbidity and other disorder characteristics on depression-related cognitive functioning.

Performance in verbal and visual short-term memory, verbal long-term memory and learning, attention, processing speed, and executive functioning was compared between a population-based sample aged 21–35 years with a lifetime history of unipolar depressive disorders (n=126) and a random sample of healthy controls derived from the same population (n=71). Cognitive functioning was also compared between the subgroups of pure (n=69) and co-morbid (n=57) depression.

The subgroups of pure and co-morbid depression did not differ in any of the cognitive measures assessed. Only mildly compromised verbal learning was found among depressed young adults in total, but no other cognitive deficits occurred. Received treatment was associated with more impaired verbal memory and executive functioning, and younger age at first disorder onset with more impaired executive functioning.

Psychiatric co-morbidity may not aggravate cognitive functioning among depressed young adults. Regardless of co-morbidity, treatment seeking is associated with cognitive deficits, suggesting that these deficits relate to more distress.

The literature suggests an association between obesity and schizophrenia but fat mass and fat-free mass, which have been shown to be more predictive of all-cause mortality than only waist circumference and obesity [body mass index (BMI) ⩾30 kg/m2], have not been reported in psychotic disorders. We examined the detailed body composition of people with different psychotic disorders in a large population-based sample.

We used a nationally representative sample of 8082 adult Finns aged ⩾30 years with measured anthropometrics (height, weight, waist circumference, fat percentage, fat-free mass and segmental muscle mass). Psychiatric diagnoses were based on a consensus procedure utilizing the Structured Clinical Interview for DSM-IV (SCID)-interview, case-notes and comprehensive register data.

Schizophrenia (including schizo-affective disorder) was associated with obesity [odds ratio (OR) 2.3, 95% confidence interval (CI) 1.5–3.6], abdominal obesity (waist circumference ⩾88 cm for women, ⩾102 cm for men) (OR 2.2, 95% CI 1.3–3.6) and with higher fat percentage (mean difference 3.8%, 95% CI 2.0–5.7%), adjusted for age and gender, than in the remaining sample. The associations between schizophrenia and low fat-free mass and decreased muscle mass on trunk and upper limbs became statistically significant after adjusting for BMI. After further adjusting for current antipsychotic medication, education, diet and smoking, schizophrenia remained associated with obesity (OR 1.9, 95% CI 1.1–3.6) and abdominal obesity (OR 3.8, 95% CI 1.5–9.4). Participants with affective psychoses did not differ from the general population.

Individuals with schizophrenia have metabolically unfavorable body composition, comprising abdominal obesity, high fat percentage and low muscle mass. This leads to increased risk of metabolic and cardiovascular diseases.

The effect of mental disorders may be particularly detrimental in early adulthood, and information on mental disorders and their correlates in this age group is important.

A questionnaire focusing on mental health was sent to a nationally representative two-stage cluster sample of 1863 Finns aged 19 to 34 years. Based on a mental health screen, all screen-positives and a random sample of screen-negatives were asked to participate in a mental health assessment, consisting of the Structured Clinical Interview for DSM-IV (SCID-I) interview and neuropsychological assessment. We also obtained case-notes from all lifetime mental health treatments. This paper presents prevalences, sociodemographic associations and treatment contacts for current and lifetime mental disorders.

Forty percent of these young Finnish adults had at least one lifetime DSM-IV Axis I disorder, and 15% had a current disorder. The most common lifetime disorders were depressive disorders (17.7%) followed by substance abuse or dependence (14.2%) and anxiety disorders (12.6%). Of persons with any lifetime Axis I disorder, 59.2% had more than one disorder. Lower education and unemployment were strongly associated with current and lifetime disorders, particularly involving substance use. Although 58.3% of persons with a current Axis I disorder had received treatment at some point, only 24.2% had current treatment contact. However, 77.1% of persons with a current Axis I disorder who felt in need of treatment for mental health problems had current treatment contact.

Mental disorders in young adulthood are common and often co-morbid, and they may be particularly harmful for education and employment in this age group.