Juha T. Karvonen

Obesity and depression: results from the longitudinal Northern Finland 1966 Birth Cohort Study

Objective:To examine the association between body size and depression in a longitudinal setting and to explore the connection between obesity and depression in young adults at the age of 31 years.Design:This study forms part of the longitudinal Northern Finland 1966 Birth Cohort Study (N=12 058). The follow-up studies were performed at 14 and 31 years. Data were collected by postal inquiry at 14 years and by postal inquiry and clinical examination at 31 years.Subjects:A total of 8451 subjects (4029 men and 4422 women) who gave a written informed consent and information on depression by three depression indicators at 31 years.Measurements:Body size at 14 (body mass index (BMI) and 31 (BMI and waist-to-hip ratio (WHR)) years and depression at 31 years by three different ways: depressive symptoms by the HSCL-25-depression questionnaire (HSCL-25), the use of antidepressants and self-reported physician-diagnosed depression.Results:Obesity at 14 years associated with depressive symptoms at 31 years; among male subjects using the cutoff point 2.01 in the HSCL-25 (adjusted odds ratio (OR) 1.97, 95% CI 1.06–3.68), among female subjects using the cutoff point 1.75 (adjusted OR 1.64, 95% CI 1.16–2.32). Female subjects who were obese both at baseline and follow-up had depressive symptoms relatively commonly (adjusted OR 1.40, 95% CI 1.06–1.85 at cutoff point 1.75); a similar association was not found among male subjects. The proportion of those who used antidepressants was 2.17-fold higher among female subjects who had gained weight compared to female subjects who had stayed normal-weighted (adjusted OR 2.17, 95% CI 1.28–3.68). In the cross-sectional analyses male subjects with abdominal obesity (WHR ⩾85th percentile) had a 1.76-fold risk of depressive symptoms using the cutoff 2.01 in the HSCL-25 (adjusted OR 1.76, 95% CI 1.08–2.88). Abdominally obese male subjects had a 2.07-fold risk for physician-diagnosed depression (adjusted OR 2.07, 95% CI 1.23–3.47) and the proportion of those who used antidepressants was 2.63-fold higher among obese male subjects than among male subjects without abdominal obesity (adjusted OR 2.63, 95% CI 1.33–5.21). Abdominal obesity did not associate with depression in female subjects.Conclusion:Obesity in adolescence may be associated with later depression in young adulthood, abdominal obesity among male subjects may be closely related to concomitant depression, and being overweight/obese both in adolescence and adulthood may be a risk for depression among female subjects.

Reasons for the diagnostic discordance between clinicians and researchers in schizophrenia in the Northern Finland 1966 Birth Cohort

Abstract.Background: The diagnosis of schizophrenia by clinicians is not always accurate in terms of operational diagnostic criteria despite the fact that these diagnoses form the basis of case registers and routine statistics. This poses a challenge to psychiatric research. We studied the reasons for diagnostic discordance between clinicians and researchers. Methods: The Northern Finland 1966 Birth Cohort (n = 11,017) was followed from mid-gestation to the end of the 31st year. Psychiatric outcome was ascertained through linkage to the national hospital discharge register containing clinical diagnoses made by the attending physician. The hospital notes of all subjects admitted to hospital during the period 1982–1997 due to psychiatric disorder were reviewed and 475 research, operational DSM-III-R diagnoses were formulated. Results: Ninety-six cases met operational criteria for schizophrenia. Fifty-five (57 %) had concordant diagnoses: both the clinical and research diagnoses were schizophrenia. Forty-one (43 %) had discordant diagnoses: the clinical diagnosis was other than schizophrenia (mainly schizophreniform or other psychosis). Discordant cases were more likely to be older at onset, experience a shorter treatment duration, fewer treatment episodes, and to have a comorbid diagnosis mental retardation. Conclusions: Clinicians do not make the diagnosis of schizophrenia as often as the application of operational criteria would suggest they should. The discordance between clinical diagnosis and the research, operational diagnosis is especially likely in cases having late onset and few contacts to psychiatric hospital.

Ability to speak at the age of 1 year and alexithymia 30 years later

OBJECTIVE We studied the association between speech development in the first year of life and alexithymia in young adulthood. METHODS The study forms a part of the Northern Finland 1966 Birth Cohort. The original material consisted of all liveborn children in the provinces of Lapland and Oulu in Finland with an expected delivery date during 1966. The comprehensive data collection began during the antenatal phase. In 1997, a 31-year follow-up study was made on a part of the initial sample. The 20-item version of the Toronto Alexithymia Scale (TAS-20) was given to 5983 subjects. Of them, 84% returned the questionnaire properly filled in. The ability to talk was classified according to whether the child spoke no words, one or two words, or three or more words at the age of 1 year. Statistical analyses on the association between the ability to speak at the age of 1 year and alexithymia at the age of 31 years were performed, adjusted for birth weight, mothers parity, place of residence and wantedness of pregnancy. RESULTS The mean of the total TAS score was lowest among early speakers and for both genders separately. The differences were statistically significant. A parallel significant difference was found among males on TAS Factors 2 and 3 and in case of females on TAS Factors 1 and 3. CONCLUSIONS We found evidence for an association between speaking development in early childhood and later alexithymia. Our results support the theory that alexithymia may be a developmental process starting in early childhood and reinforcing itself in a social context.

Childhood family structure and personality disorders in adulthood

BACKGROUND The association between childhood family structure and sociodemographic characteristics and personality disorders (PDs) in a general population sample was studied. METHODS This study is a substudy of the prospective Northern Finland 1966 Birth Cohort Project with 1588 young adult subjects. The case-finding methods according to the DSM-III-R criteria for PDs were: (1) Structured Clinical Interview for DSM-III-R (SCID) for 321 cases who participated in a 2-phase field study, (2) Finnish Hospital Discharge Register data, and (3) analysis of the patient records in public outpatient care in 1982-1997. Statistical analyses were performed on the association between PDs and family background factors. RESULTS Altogether 110 (7.0%) of the subjects had at least one probable or definite PD. After adjusting for confounders (gender, parental social class and parental psychiatric disorder) the results indicated that single-parent family type in childhood was associated with cluster B PDs in adulthood. Being an only child in childhood was associated with cluster A PDs. No special childhood risk factors were found for cluster C PDs. CONCLUSIONS Results suggest that single-parent family type at birth and being an only child in the 1960s are associated with PD in adulthood. Further studies are needed to explore the psychosocial aspects of family environment which may nowadays promote vulnerability to PDs in adulthood.

Comparison of hospital-treated personality disorders and personality disorders in a general population sample

The distribution of personality disorders (PDs) was explored in hospital-treated subjects and in a population subsample. This study forms a part of the Northern Finland 1966 Birth Cohort study. Hospital case records of psychiatric treatment periods of all cohort members (n=11 017) were reviewed and re-checked against DSM-III-R criteria. A subsample of the cohort members living in Oulu (n=1609) were invited to a two-stage psychiatric field survey with Structured Clinical Interview for DSM-III-R (SCID) as a diagnostic method. The most common PDs in hospital-treated sample were cluster B PDs (erratic). In the population subsample, cluster C PDs (anxious) formed the majority.

Somatization symptoms in young adult Finnish population—Associations with sex, educational level and mental health

We assessed somatization symptoms and their associations among a 31-year-old Finnish population sample (n=1598). Data on somatization symptoms were gathered from a review of all medical public outpatient records. Subjects with four or more somatization symptoms according to the DSM-III-R criteria were classified as somatizers. Ninety-seven (83 females) DSM-III-R somatizers (6.1%) were found. Somatization associated with female sex, lower educational level and increased psychiatric morbidity. Roughly half of the somatizers had a comorbid psychiatric disorder. Mood disorders did not associate specifically with somatization—in fact, after adjusting for sex and educational level only anxiety disorders and personality disorders associated with somatization. It may be concluded that it is important to recognize psychiatric disorders in subjects with somatization symptoms, especially as these symptoms have been shown to be treatable with both psychotherapy and psychiatric medication.

Temperament profiles in personality disorders among a young adult population

The objective of this study was to describe the temperament dimension profiles assessed by the Temperament and Character Inventory (TCI) among young adults with the DSM-III-R personality disorder (PD). Our hypothesis was that PD clusters and separate PDs can be distinguished from one another by their specific temperament profiles. As a part of the 31-year follow-up survey of the prospective Northern Finland 1966 Birth Cohort, the cohort members living in the city of Oulu at the age of 31 years (n=1609) were invited to participate in a two-phase field study. The Structured Clinical Interview for DSM-III-R for PDs (SCID–II) was used as diagnostic instrument. The final study sample consisted of the 1311 subjects who had completed the Hopkins Symptom Check List-25 questionnaire for screening and had given a written informed consent. Of the 321 SCID interviewed subjects, 74 met the criteria for at least one PD and had completed the TCI. The mean TCI scores of subjects with PD and control subjects without PD (n=910) were compared. Low Novelty Seeking, high Harm Avoidance and low Reward Dependence characterized cluster A and C PDs. Subjects with a cluster B PD did not differ from controls, except for Novelty Seeking, which was high. The temperament dimensions could not distinguish different PDs very well, with the only exception of persons with obsessive–compulsive PD. PD clusters were associated with different profiles of temperament, lending some support for Cloningers typology.

Comorbidity of hospital-treated psychiatric and physical disorders with special reference to schizophrenia

Abstract We studied the comorbidity of psychiatric and physical disorders in a sample ( n = 11017) from the unselected, general population, Northern Finland 1966 Birth Cohort. During the period 1982–1994, hospital-treated psychiatric patients were more likely than people without psychiatric diagnoses to have been treated for physical disease in hospital wards, 298 out of 387 (77.0%) vs 6687 out of 10 630 (62.9%) (OR = 2.0, 95% CI=1.6−2.5). Injuries, poisonings and indefinite symptoms were a more common reason for hospital treatment in people with schizophrenia or other psychiatric disorder as compared with people without a psychiatric disorder. Men with psychiatric disorder had more than a 50-fold risk for poisoning by psychotropic drugs (OR = 52.6, 95% CI=27.7−99.8), women with psychiatric disorder a 20-fold risk (OR = 19.0, 95% CI=9.5–38.1) and schizophrenics more than a 30-fold risk (OR = 37.5, 95% CI=19.1–73.8). Men with psychiatric disorders were more commonly hospitalised for a variety of gastrointestinal disorders and circulatory diseases (OR = 2.3, 95% CI=1.2–4.4), as compared with men with no psychiatric disorder. Respiratory diseases (OR = 2.2, 95% CI=1.2–4.2), vertebral column disorders (OR = 4.2, 95% CI=1.8–9.9), gynaecological disorders (OR = 2.1, 95% CI=1.2–3.6) and induced abortions (OR = 1.8, 95% CI=1.2–2.7) were more prevalent in women with psychiatric disorder than in other women. Epilepsy was strongly associated with schizophrenia (OR = 11.1, 95% CI=4.0–31.6). Nervous and sensory organ diseases in general (OR = 2.5, 95% CI=1.1–5.8) and inflammatory diseases of the bowel (OR = 12.8, 95% CI=3.8–42.7) were also overrepresented in schizophrenia when compared with people without a psychiatric disorder. Our results indicate that physicians must be alert for psychiatric disorder, and mental health professionals must be aware of the considerable physical morbidity in their patients.

Temperament profiles in women with somatization disorder

Hakala et al. reported in the Journal that 10 women suffering from somatization disorder (SD) had low novelty-seeking (NS) and high harm-avoidance (HA) as assessed on the Temperament and Character Inventory (TCI). We consider it important to complement these results with some parallel findings. We identified nine female subjects suffering from SD in our population-based sample of 1598 subjects aged in their 30s. We reanalyzed their TCI scores and found that mean NS was 19.6 4.8 and mean HA was 14.3 9.7. The NS score and HA score determined in our study were found to be between those of subjects suffering SD and healthy controls in the Hakala et al. study: NS 17.6 3.0 versus 22.3 4.7 and HA 18.5 5.4 versus 11.8 7.1, respectively. Subjects in the Hakala et al. study were diagnosed on DSM-IV criteria, they were older, and they had no comorbid psychiatric disorders. They originated from South-west Finland. They were identified in psychiatric treatment units. We used DSM-III-R criteria in a sample of younger subjects originating from northern Finland, and our subjects had significant comorbidity for psychiatric disorders. There are few studies assessing temperament and somatization. Differences in diagnostic criteria, age of subjects and comorbidities might explain the discrepancy between results. We studied a population-based cohort of SD subjects and Hakala et al. studied a patient sample. There might also be subgroups among SD patients, which need different approach to be recognized and treated.