Thirteen year follow up of long term treated psychotic disorder: Personality aspects

Introduction

Psychotic disorders often cause a drastic change in the life situation of the affected individual. Personality is an aspect that can affect the symptoms and social function in psychotic disorders.

Objectives

No study has examined stability of personality traits exceeding five years in patients with schizophrenia. The aim of this study was to investigate the stability of personality traits over a 13-year period among patients with psychotic disorder and healthy individuals and to evaluate case-control differences.

Methods

At three occasions during a 13-year period patients with psychotic disorders (n=28) and non-psychotic individuals (n=57) completed Swedish universities Scales of Personality (SSP). For all the individuals within- and between-subject analyses were performed at three occasions for all 13 subscales and the three overall factors of SSP. Correlations, means and SDs were calculated.

Results

Tests of within-subject correlations showed differences in two subscales: Lack of Assertiveness, which were influenced by age and Physical Trait Aggression, where patients ratings were stable, whereas controls rated themselves less aggressive at higher age. Between-subjects correlations showed differences regarding any of the parameters diagnosis, time, age, gender or age x gender in nine of the 13 subscales as well as in factor Neuroticism.

Conclusions

Long term follow-up showed a generally high stability of personality traits measured with SSP, especially among patients. Between-subject analyses over the 13 years showed that patients differed compared to controls for the SSP factor Neuroticism as well as the subscale Detachment, which is in accordance with previous studies.

Increased activity of lysozyme and complement system in Atlantic halibut exposed to elevated CO2 at six different temperatures

Ocean acidification and rising seawater temperature are environmental stressors resulting from the continuous increase of the atmospheric CO₂ concentration due to anthropogenic activities. As a consequence, marine fish are expected to undergo conditions outside of their tolerance range, leading to physiological challenges with possible detrimental implications. Our research group has previously shown that exposure to elevated CO₂ modulated the immune system of the Atlantic halibut. To further investigate this finding, we analysed non-specific immune components in blood plasma of Atlantic halibut (Hippoglossus hippoglossus) juveniles acclimated to six different temperatures (5, 10, 12, 14, 16 and 18 °C), and to water pH of 8.0 (control) or 7.6 (predicted for year 2100) for three months. Plasma ions (K⁺, Na⁺, Ca⁺⁺, Cl^-) and lactate concentrations were also measured. The analysis of plasma ions did not show any trends related to temperature or CO₂ exposure, and the majority of the experimental fish were able to maintain ionic balance. The results show that both innate immune components (lysozyme and alternative complement system) had increased activities in response to elevated CO₂, representing a CO₂-related impact on the halibut's immune system. The increased activity of lysozyme and complement system is possibly part of the acclimatization process, and might be protective.

Plasma growth hormone-binding protein levels in Atlantic salmon Salmo salar during smoltification and seawater transfer

Specific growth hormone (GH)-binding protein (Ghbp) was purified from Atlantic salmon Salmo salar and rainbow trout Oncorhynchus mykiss plasma with immunoprecipitation and characterized in cross-linking studies using autoradiography and western blots. The size of the Ghbp was estimated to be c. 53 kDa. A radioimmunoassay was established to measure Ghbp in salmonids, using antibodies specific against the extracellular segment of the S. salar growth hormone receptor 1 (grh1; GenBank AY462105). Plasma Ghbp levels were measured in S. salar smolts in fresh water and after transfer to seawater (SW; experiments 1 and 2), and in post-smolts kept at different salinities (0, 12, 22 and 34) for 3 months (experiment 3). A transient increase in plasma Ghbp, which lasted for 1 month or less, was noted in smolts after transfer to SW. Concomitantly, plasma GH and gill Na(+) -K(+) -ATPase activity increased during smoltification (in experiment 2). No difference in plasma Ghbp was evident between post-smolts kept at different salinities, although the fish kept at salinity 34 had higher plasma GH than the group kept at salinity 22 and higher hepatic ghr1 expression than post-smolts kept at salinity 12. This suggests that plasma Ghbp regulation may respond to salinity changes in the short term. The lack of correlation between Ghbp, plasma GH and hepatic ghr1 expression in the long-term post-smolt experiment indicates that Ghbp levels may be regulated independently of other components of the endocrine GH system in salmonids.

Not 15 but 50% of smokers develop COPD?--Report from the Obstructive Lung Disease in Northern Sweden Studies

BACKGROUND

The prevalence of chronic obstructive pulmonary disease (COPD) according to guidelines of today seems considerably higher than has been reported also in recent literature.

AIM

To estimate the prevalence of COPD as defined by British Thoracic Society (BTS) criteria and the recent global initiative for chronic obstructive lung disease (GOLD) criteria. Further aims were to assess the proportion of underdiagnosis and of symptoms in subjects with COPD, and to study risk factors for COPD.

METHODS

In 1996, 5892 of the Obstructive Lung Disease in Northern Sweden (OLIN) Study's first cohort could be traced to a third follow-up survey, and 5189 completed responses (88%) were received corresponding to 79% of the original cohort from December 1985. Of the responders, a random sample of 1500 subjects were invited to a structured interview and a lung function test, and 1237 of the invited completed a lung function test with acceptable quality.

RESULTS

In ages >45 years, the prevalence of COPD according to the BTS guidelines was 8%, while it was 14% according to the GOLD criteria. The absolutely dominating risk factors were increasing age and smoking, and approximately a half of elderly smokers fulfilled the criteria for COPD according to both the BTS and the GOLD criteria. Family history of obstructive airway disease was also a risk factor, while gender was not. Of those fulfilling the BTS criteria for COPD, 94% were symptomatics, 69% had chronic productive cough, but only 31% had prior to the study been diagnosed as having either chronic bronchitis, emphysema, or COPD. The corresponding figures for COPD according GOLD were 88, 51, and 18%.

CONCLUSIONS

In ages >45 years, the prevalence of COPD according to the BTS guidelines was 8%, and it was 14% according to the GOLD criteria. Fifty percent of elderly smokers had developed COPD. The large majority of subjects having COPD were symptomatic, while the proportion of those diagnosed as having COPD or similar diagnoses was small.

Does non-responder bias have a significant effect on the results in a postal questionnaire study?

BACKGROUND AND AIM

In epidemiological questionnaire studies results can be influenced by non-responder bias. However, in respiratory epidemiology this has been analysed in very few recently published papers. The aim of our paper is to assess if the results found in our previous postal questionnaire study in an adult population in Northern Finland were biased by non-response.

METHODS

A random sample of 385 persons from the 1,284 non-responders in a previous postal questionnaire study was examined. The same questionnaire as in the original study was again mailed to these persons, and those still not answering were contacted by phone.

RESULTS

Totally 183 complete answers (48%) were collected. Lack of interest (56%) and forgetting to mail the response letter (22%) were the most common reasons to non-response. Typical non-responders were young men and current smokers who less frequently reported respiratory symptoms in exercise and asthma than the responders in the original study. Answers collected by phone gave for some questions higher prevalence rates than postal answers.

CONCLUSION

Firstly, in this population the response rate (83.6%) in the original study was high enough to provide reliable results for respiratory symptoms and diseases, only the prevalence of current smoking was biased by non-response. Secondly, the methods used for collecting responses in a non-response study may influence the results.

Underdiagnosis of chronic obstructive pulmonary disease in Northern Sweden

OBJECTIVE

To assess underdiagnosis of chronic obstructive pulmonary disease.

MATERIAL AND METHODS

Two cross-sectional studies of respiratory symptoms and diseases in two population samples of the same age living in the same areas in northern Sweden were performed 6 years apart. In 1986, 5698 (86%) out of 6610 subjects aged 35-36, 50-51 and 65-66 years responded to a postal questionnaire. In 1992 an identical study was performed, and 5617 subjects (87%) out of 6434 responded. Lung function measurements were performed in stratified samples.

RESULTS

Of the subjects diagnosed with chronic bronchitis only 25% in 1986 and 23% in 1992 had been diagnosed prior to the study as having chronic bronchitis, emphysema or chronic obstructive pulmonary disease (COPD). Chronic airflow limitation (CAL), used as a surrogate variable for COPD and defined as FEV1/VC <70% and FEV1 <80% of predicted value, was found in 171 subjects in 1986-1987 (12% of the examined subjects), and 166 subjects in 1993-1994 (11%). In 1986-1987, 26% of the subjects with CAL had been diagnosed as having chronic bronchitis or emphysema prior to the survey, while a diagnosis of either asthma, chronic bronchitis or emphysema, or use of asthma medicines, was found in 58%. The corresponding figures in 1993-1994 were 31% and 63%, respectively. The great majority of the subjects with CAL had recurrent wheeze, dyspnoea and chronic productive cough.

CONCLUSION

Approximately 60% of the subjects with chronic airflow limitation had been diagnosed prior to the survey as having asthma, chronic bronchitis or emphysema, or were using asthma medicines. The results were similar in 1986-1987 and 1993-1994.

Asthma, chronic bronchitis and respiratory symptoms among adults in Estonia according to a postal questionnaire

Epidemiological studies indicate a lower prevalence of asthma in Eastern than Western Europe. This study of the prevalence of asthma, chronic bronchitis, and respiratory symptoms was performed in three different regions of Estonia, a state incorporated in the Soviet Union until 1991. A postal questionnaire was sent to a random sample of 24,307 of the population aged 15-64 years. The response rate was 77.6%. The prevalence of physician-diagnosed asthma was 2.0% or considerably lower than in Northern and Western European countries. The prevalence of wheezing last 12 months, 21.7%, recurrent wheeze, 13.3%, and attacks of shortness of breath, 12.5%, were similar or even higher compared with prevalence rates found in the Nordic countries. The prevalence of physician-diagnosed chronic bronchitis was 10.7%, and was higher among women than in men, although the proportion of current smokers among men, 57%, was considerably greater than in women, 28%. A possible explanation to the high prevalence of respiratory symptoms also among non-smoking women may be exposure to environmental tobacco smoke in small, crowded Estonian homes. Diagnostic criteria based on the Soviet-time definitions is discussed as a possible explanation to the low prevalence of physician-diagnosed asthma and high prevalence of chronic bronchitis in Estonia compared with other Northern European countries.

Incidence of physician-diagnosed asthma in adults--a real incidence or a result of increased awareness? Report from The Obstructive Lung Disease in Northern Sweden Studies

Only limited data are available about the incidence of asthma based on longitudinal prospective studies. Further, the results from different studies on incidence vary considerably depending on the age composition of the cohorts under study, the used methods and the criteria for disease. Also among adults high incidence rates have been reported during recent years. The aim of this study was to examine to what extent the incidence of physician-diagnosed asthma could be explained by a real incidence of the disease, and to what extend by an increased diagnostic activity or altered diagnostic praxis. Another aim was to study risk factors for asthma based on incident cases. Three cross-sectional surveys have been performed in the same population sample living in the northern-most province of Sweden, Norrbotten. The first survey was performed in 1986, and 5698 subjects, 86% of those invited, responded to a postal questionnaire. Of these, 4754 subjects (83%) participated at the third survey in 1996. After exclusion of all subjects who had reported that they had asthma in 1986, or had been classified as having asthma in 1986, 68 men and 98 women (P=0.02) reported in 1996 that they had been diagnosed as having asthma by a physician. Thus, the cumulative incidence for the 10-year period was 3.2% among men and 4.5% among women. After correction for subjects who already in 1986 had reported symptoms common in asthma, or had been classified as having chronic bronchitis, 97 subjects with incident asthma remained, which corresponded to an annual incidence rate among men of 1.7 and among women of 2.9/1000 persons year(-1) (P=0.1). Clinical examinations confirmed asthma in a large majority of these 97 subjects. Significant risk factors were family history of asthma, both ex- and current smoking, and female sex. The socio-economic groups manual workers and assistant non-manual employees were associated with incident asthma, although not significantly. The increasing prevalence of asthma among adults during recent 10-20 years may to a considerable extent be explained by an increased diagnostic activity or altered diagnostic praxis. Use of different methods when measuring incidence may in part explain the extremely diverging incidence rates of asthma found in different studies.

Smoking, respiratory symptoms, and diseases : a comparative study between northern Sweden and northern Finland: report from the FinEsS study

STUDY OBJECTIVES

The influences of different smoking categories on the prevalence of respiratory symptoms, asthma, and chronic bronchitis have been examined in the most northern province of Sweden, Norrbotten, and in Lapland, Finland. The two areas have similar geographic and demographic conditions.

METHODS AND STUDY POPULATION

The study is a part of the FinEsS studies, which are epidemiologic respiratory surveys in progress in Sweden, Finland, and Estonia. A random sample of 20- to 69-years-olds were invited to answer a postal questionnaire about respiratory symptoms, smoking habits, and occupation. In Norrbotten, 8,333 subjects were invited and 7,104 responded (85%). In Lapland, 8,005 were invited and 6,633 responded (83%).

RESULTS

The participation by age and sex was similar in both countries. The prevalence of smokers in Lapland was 32% vs 26% in Norrbotten. Significantly more women than men in Norrbotten were smokers, while the opposite was true for Lapland. Sputum production was the most prevalent symptom in both areas, 25% in Lapland vs 19% in Norrbotten. The prevalence of chronic productive cough was 11% in Lapland and 7% in Norrbotten. Bronchitic symptoms were more prevalent in Lapland among both smokers and nonsmokers. A positive family history of chronic obstructive airway disease together with increased number of consumed cigarettes showed an additive effect for both chronic productive cough and wheezing. The odds ratio (OR) for wheezing during the last 12 months was 3.8 for subjects without a family history of obstructive airway disease who consumed > 14 cigarettes per day compared with nonsmokers, but if the subjects had a family history of obstructive airway disease, the risk for wheezing increased to OR 8.4.

CONCLUSION

Bronchitic symptoms were more common in Finland. The difference remained also after correction for demographic variables including smoking habits, age and socioeconomic group, and family history of obstructive airway disease. Identical methods, sample composition, and the high participation rate contribute to the validity of the results. Air pollution, including environmental tobacco smoke, may contribute to the difference. To explain the difference, further analysis and investigations of social and environmental factors as well as genetic factors are needed.

Incidence and remission of asthma in schoolchildren: report from the obstructive lung disease in northern Sweden studies

OBJECTIVE

An increasing prevalence of asthma has been reported worldwide as well as in Sweden. In 1996, the prevalence of asthma and type 1 allergy was investigated in a cohort of 3525 children 7 and 8 years old in 3 areas of northern Sweden. The aim of the present study was to estimate the incidence of asthma and to identify risk factors for incident cases over 1 year.

METHODS

The study started with a parental questionnaire, the International Study of Asthma and Allergies in Childhood questionnaire with additional questions, a skin prick test, and a validation study. The cohort was followed up after 1 year with the same questions. The response rate to the questionnaire was 97% in 1996, and 3339 children (97%) participated both in 1996 and 1997.

RESULTS

The incidence of physician-diagnosed asthma was 0.9/100/year; of wheezing, 3.8/100/year; and of new frequent or daily users of asthma medicines, 1.1/100/year. There was no difference by sex. The risk factor pattern based on incident cases of asthma was different from that based on prevalent cases. Significant risk factors for incident asthma were a positive skin test (odds ratio [OR]: 9.3; 95% confidence interval [CI]: 3.8-22.7); low birth weight (OR: 7.4; 95% CI: 2.2-24.5); and family history of asthma (OR: 2.6; 95% CI: 1.1-6.3). Having or having had pets at home was associated with a decreased risk for asthma and wheezing based on prevalent cases, although it was associated with an increased risk for incidence of wheezing (OR: 2.9; 95% CI: 1.3-6.2). Remission of asthma, which was reported by 10% of the children with current asthma during 1 year, was associated with a negative skin test.

CONCLUSION

The incidence of asthma at the age of 8 years was high, but remission was also common. Important risk factors for the development of asthma at this age were type 1 allergy, low birth weight, and family history of asthma. Furthermore, the results suggest that in a region where sensitivity to domestic animals is a strong risk factor for asthma, the presence of pets in the home may have different effects in early childhood compared with later in childhood.

A 39-year followup of the Genain quadruplets

The Genains, a unique group of monozygotic female quadruplets, all developed a schizophrenic disorder by age 24. They have been studied since the 1950s, because of the rarity of this occurrence (estimated to be one in 1.5 billion) and because their illnesses varied in severity. The identical inheritance would tend to rule out genetic differences as the cause of the neuropsychological differences; however, we cannot disentangle the effects of early brain injury and harsh punitive treatment as factors accounting for the differences in the severity of their disorders. We conducted neuropsychological examinations of the Genains at age 66, compared their test profiles, and contrasted certain test scores at 66 with those at ages 27 and 51. Test results indicate generally stable (or even improved) performance over time and support the notion that cognitive decline is not a degenerative process in schizophrenia. The Genains remind us of the exquisite interaction among variables that must be understood before additional, satisfactory progress can be made in preventing the development and predicting the course of schizophrenia.

Increasing prevalence of asthma but not of chronic bronchitis in Finland? Report from the FinEsS-Helsinki Study

To assess the prevalence of asthma, chronic bronchitis and respiratory symptoms, and to calculate risk factors for them, we performed a postal survey in Helsinki, the capital of Finland. During the spring of 1996, questionnaires were mailed to a random sample of 8000 individuals aged 20-69. The total response rate was 76%, with 6062 complete answers. The prevalence of having ever had asthma was 7.2%, physician-diagnosed asthma was 6.6% and physician-diagnosed chronic bronchitis was 3.7%. Asthma was significantly more common among women than men, but no gender differences existed in prevalence of chronic bronchitis. The most common respiratory symptom was sputum production when coughing, reported by 27%. During the previous 12 months, wheezing had occurred in 20% and attacks of shortness of breath in 13% of subjects. Generally, the prevalence of different respiratory symptoms were significantly higher among smokers. The most important risk factor for asthma was a family history of asthma (Odds ratio:OR 3.3). Multivariate analysis revealed that being a member of the socioeconomic group, manual workers, was associated with a significantly increased risk for chronic productive cough (OR 1.7), and for wheezing during the previous 12 months (OR 1.7). Manual workers of both genders had the highest prevalence of asthma, chronic productive cough and wheezing during the previous 12 months. The prevalence of asthma in Helsinki was higher than previously found in Finland, and was at a similar level to that of other Nordic countries. In contrast, prevalence of chronic bronchitis was lower than previously shown in Finland.

Different pattern of risk factors for atopic and nonatopic asthma among children--report from the Obstructive Lung Disease in Northern Sweden Study

BACKGROUND

A cross-sectional study was performed among 78-year-old schoolchildren during the winter of 1996 in three municipalities in the most northern province of Sweden, Norrbotten. The study was the starting point of a longitudinal study of asthma, rhinitis, eczema, and type-1 allergy, and provided data on prevalence and risk factors for these conditions. The aim of the present study was to validate the classification of asthma based on a parental questionnaire, and to examine risk factors for atopic and nonatopic asthma.

METHODS

The ISAAC questionnaire with additional questions was distributed by the schools to the parents. The response rate was 97%, and 3431 completed questionnaires were returned. The children in Kiruna and Luleå were also invited to be skin tested, and 2149 (88%) were tested with 10 common airborne allergens. A structured interview was administered by pediatricians in stratified samples of the children to test the validity of the diagnosis of asthma based on the questionnaire.

RESULTS

After the validation study, the prevalence of "ever asthma" was estimated to be 8.0%. The specificity of the question, "Has your child been diagnosed as having asthma by a physician?", was high, >99%, while the sensitivity was around 70%. The strongest risk factor for "ever asthma" was a positive skin test (OR 3.9). Risk factors for asthma in the asthmatics who were not sensitized were family history of asthma, OR 3.6; breast-feeding less than 3 months, OR 1.8; past or present dampness at home, OR 1.8; smoking mother, OR 1.7; and male sex, OR 1.6. Among the sensitized asthmatics, only a family history of asthma was a significant risk factor (OR 3.0), while breast-feeding less than 3 months was not associated with an increased risk (OR 1.0). A synergistic effect between genetic and environmental factors was found especially in the nonatopic asthmatics; the children with a family history of asthma who had a smoking mother and past or present dampness at home had an OR for "ever asthma" of 13.

CONCLUSIONS

Different risk-factor patterns were found for asthma and type-1 allergy. In addition, the risk factors for atopic or allergic asthma diverged from those for nonatopic asthma.

Remission of asthma in the middle aged and elderly: report from the Obstructive Lung Disease in Northern Sweden study

BACKGROUND

Remission of asthma in adults has been considered to be low but is still not well documented. In children remission occurs with a rate estimated at approximately 50%. Remission of asthma in middle aged and elderly subjects was investigated as part of a population based study of respiratory diseases in Northern Sweden.

METHODS

In 1986 86% of 6610 subjects participated in a questionnaire survey. After a clinical validation study 300 subjects were diagnosed as having current asthma. In 1996 5935 subjects of the cohort could be traced for a third survey and 87% participated. Of the subjects with current asthma in 1986, 267 participated. In addition, 60 symptomatic subjects were classified as suspected asthma and 58 of them participated in 1996. Remission of asthma was defined as no recurrent wheeze, no attacks of shortness of breath, and no use of asthma medicines in 1996.

RESULTS

Remission of asthma during the 10 year period under study was 6%. In subjects with suspected asthma, remission occurred in 22%. The average annual remission rate was less than 1%. Remission was associated with previously mild disease and cessation of smoking.

CONCLUSION

Remission of asthma or the disappearance of its symptoms to an asymptomatic latent phase appeared to be rare in middle aged and elderly subjects.

Growth hormone increases aggressive behavior in juvenile rainbow trout

The aim of the present study was to clarify the role of growth hormone in social interactions in juvenile salmonids. Growth hormone increases the metabolic demands and feeding motivation in teleost fish. As a consequence, growth hormone may increase aggression levels and/or fighting ability. To test these hypotheses we observed agonistic behavior in pairs of juvenile rainbow trout (Oncorhynchus mykiss) consisting of two control fish (C/C pairs), two growth hormone-treated fish (GH/GH pairs), or one growth hormone-treated and one control fish (C/GH pairs). The initiator and the winner of each act of aggression were registered. Aggression was lowest in the C/C pairs, intermediate in the C/GH pairs, and highest in the GH/GH pairs, with the difference between the C/C pairs and the GH/GH pairs being significant. This supports the hypothesis that GH increases aggression levels. However, in the C/GH pairs, the number of conflicts won by GH-treated and control fish did not differ significantly. Thus, because social status was not increased, GH did not appear to affect fighting ability. We suggest that growth hormone affects aggression indirectly by increasing the swimming activity, and/or by inducing defense of a larger territory, thereby increasing the encounter rate between opponents. Since increased aggression can incur energetic and mortality costs, there may be selection against high GH levels in natural populations.

Are symptoms of obstructive sleep apnoea syndrome related to bronchitic symptoms or lung function impairment? Report from the Obstructive Lung Disease in Northern Sweden Study

To investigate whether the high prevalence of symptoms related to obstructive sleep apnoea syndrome (OSAS) in a bronchitic cohort is correlated with the bronchitic symptoms or lung function impairment we examined two cohorts with bronchitic symptoms (n = 357 and 82) and a reference group who had reported no respiratory symptoms in a previous survey in 1986 (n = 140). The study was a part of the Obstructive Lung Disease in Northern Sweden Study and included clinical examination and lung function tests. Although lung function measured as FEV1 percentage predicted was correlated with bronchitic symptoms we found that bronchitic symptoms and body mass index but not lung function impairment were correlated with symptoms related to obstructive sleep apnoea. According to our findings it was the various bronchitic symptoms such as longstanding cough, wheezing, sputum production and chronic productive cough that were correlated with OSAS symptoms. This might be due to increased upper airway swelling or increased upper airway resistance, and lung function impairment does not seem to be responsible for the high prevalence of symptoms related to obstructive sleep apnoea in this bronchitic cohort.

Asthma, type-1 allergy and related conditions in 7- and 8-year-old children in northern Sweden: prevalence rates and risk factor pattern

As a first step in an intervention study of asthma and allergic diseases among school children, a cross-sectional study was performed during Winter 1996 in three towns (Kiruna, Luleå and Piteå) in the northernmost province of Sweden, Norrbotten. The cross-sectional study aimed to measure the prevalence of asthma, type-1 allergy and allergic diseases in order to make it possible to measure the incidence of the diseases, conditions and symptoms related to the diseases. Another aim was to perform a screening for possible risk factors. All children enrolled in the first and second classes at school, 7 and 8 years old, were invited to take part in this study. The ISAAC questionnaire with added questions about symptoms, morbidity, heredity and environment was distributed by the schools to the parents. The response rate was 97%, and 3431 completed questionnaires were returned. The children in two of the municipalities were also invited to skin test, and 2149 (88%) were tested with 10 common airborne allergens. The results showed that 7% of the children were currently using or had used asthma medicines during the last 12 months. Six percent had asthma diagnosed by a physician, and 4% were using inhaled corticosteroids. The prevalence of wheezing during the last 12 months was 12%, rhinitis without colds 14%, and eczema 27%, while 21% had a positive skin test. The respiratory symptoms and conditions were significantly greater in boys and, further, they were most prevalent in Kiruna in the very north, though not significantly. Type-1 allergy and asthma had different risk factor patterns. The main risk factors for asthma were a family history of asthma (OR = 3.2) followed by past or present house dampness (OR = 1.9), male sex (OR = 1.7) and a smoking mother (OR = 1.6). In Kiruna, when none of these three risk factors were present, none of the children had asthma, but when all three were present, 38% of these children were using asthma medicines.

Prevalence and incidence of asthma and rhinoconjunctivitis in Swedish teenagers

In 1987, we studied the prevalence of asthma and rhinoconjunctivitis in 1112 grade-eight students in the town of Umeå, northern Sweden. The present study is based on the same cohort, reinvestigated in 1991. We aimed to estimate the changes in the prevalence of asthma and rhinoconjunctivitis and to examine some presumed risk factors of asthma and rhinoconjunctivitis. A postal questionnaire on present asthma, rhinoconjunctivitis, symptoms from the upper and lower airways, and the need for medication was used. Questions about living conditions, smoking, and present education were also included. The questionnaire was answered by 89% (990) of the subjects. The prevalence of self-reported asthma was 10.8% (boys 7.9%, girls 13.7%). The incidence rate/year was 1.1%, the remission rate/year was 5.7%, and the relapse rate/year was 10%. The risk factors for developing asthma appeared to be atopy, having a family history of asthma or rhinoconjunctivitis, and smoking. The prevalence of self-reported rhinoconjunctivitis was 14.3% (boys 15.6%, girls 13.1%). The incidence rate/year was 1%, the remission rate/year was 22%, and the relapse rate/year was 11%. Stopping smoking and having no family history of rhinoconjunctivitis or asthma appeared to favor remission in rhinoconjunctivitis.

Incidence of asthma in adults--report from the Obstructive Lung Disease in Northern Sweden Study

Incidence studies offer a better opportunity to study risk factors for asthma than do prevalence studies. However, regular prospective follow-ups of large cohorts are difficult to perform, and that is why direct measurement of the incidence rate of asthma is almost impossible. Thus, cross-sectional follow-up studies of defined cohorts can be used to provide data on incidence. In 1986, a postal questionnaire survey on respiratory symptoms and diseases was performed in the northernmost province of Sweden. The population sample comprised all subjects born in 1919-20, 1934-5, and 1949-50 in eight representative areas of the province, which comprises 25% of the total area of Sweden. Completed answers were given by 5698 subjects (86%) of the 6610 subjects invited to the study. In 1992, the cohort was invited to a follow-up survey during the same season as in 1986, and 6215 subjects were traced. Of the 5393 subjects who answered the questionnaire, 4932 had participated in the 1986 survey, or 87% of those who participated in 1986. For the period 1986-92, the cumulative incidences of asthma were 4.9 and 5.0%, respectively, as assessed by the questions, "Have you ever had asthma?" and "Have you been diagnosed as having asthma by a physician?" Thus, the results indicate a mean annual cumulative incidence of asthma of 0.8%. After correction of the results for subjects who were diagnosed as having asthma in the clinical part later in the 1986 study, the mean annual cumulative incidence of asthma was found to be 0.5%. Risk factors were family history of asthma (OR 3.46) and current and former smoking, while female sex was a strong trend.

Prodynorphin allelic distribution in Scandinavian chronic alcoholics

Two regions of the human prodynorphin gene, the exon 4-region coding for the opioid peptides and the putative promotor/exon 1-region were analyzed for possible presence of polymorphisms. No polymorphism was detected in the exon 4-region, whereas a GC/AT base-pair exchange was observed 301 base pairs upstream of the exon 1/intron A boundary. This polymorphic marker was examined in Scandinavian chronic alcoholics (n = 70) and control subjects (n = 55). Prodynorphin allelic distributions were not significantly different in alcoholic patients and control subjects. The results suggest that no major influence on alcoholism is exerted through genes associated with this prodynorphin allelic marker.

Ciliary neurotrophic factor null mutation and schizophrenia in a Swedish population

According to the maldevelopmental hypothesis, the neurotrophic factor system represents an important area which might be genetically and neurochemically involved in the etiopathogenesis of schizophrenic psychoses. Patients suffering from schizophrenic psychoses and control persons were genotyped for a null mutation of the ciliary neurotropic factor gene. There were no significant differences in the allelic and genotypic distributions in the total schizophrenic and control samples. However, there was a negative association with a family history of psychosis. Thus, it cannot be excluded that this genetic variant represents a vulnerability marker for specific schizophrenic subtypes. The development of valid diagnostic instruments based on biological criteria is crucial for schizophrenia research; more homogeneous subgroups are more likely to represent distinct nosological entities than the heterogenous group of diseases presently categorized as schizophrenia.

Tyrosine hydroxylase and dopamine D4 receptor allelic distribution in Scandinavian chronic alcoholics

Associations of polymorphic genetic markers at the tyrosine hydroxylase (TH) and dopamine D4 receptor (DRD4) loci were examined in Scandinavian chronic alcoholics (n = 72) and control subjects (n = 67). Patients were divided into subgroups with regard to the presence of parental alcoholism and age of onset. Neither the TH nor the DRD4 allele distributions were significantly different when alcoholic samples were compared with control subjects. However, a tendency to high prevalence for 1 of the 5 TH alleles assayed (TH-K3) was observed in a subsample of 44 alcoholics characterized by late onset when compared with control subjects (27.3% vs. 10.6%, p = 0.041). Results suggest that no major influence on alcoholism is exerted through genes associated with the DRD4 or TH allelic markers examined.

Symptoms related to snoring and sleep apnoea in subjects with chronic bronchitis: report from the Obstructive Lung Disease in Northern Sweden Study

To assess the relationship between chronic bronchitis and obstructive sleep apnoea, a postal survey was performed. A postal questionnaire was sent to 523 subjects identified as having chronic bronchitis or long-standing cough and sputum production in the Obstructive Lung Disease in Northern Sweden Study I (OLIN I). In 1986-88, all 6610 adults born in 1919-20, 1934-35 and 1949-50 living in representative areas in Northern Sweden were screened for airway diseases according to different methods. A random sample of healthy adults identified in the screening were chosen as references (n = 625). Subjects were asked about a variety of airway symptoms, smoking habits and symptoms related to obstructive sleep apnoea syndrome (OSAS). In the bronchitic group, 20% did not report bronchitic symptoms in the present study, and 26% of the formerly healthy reference group reported at least one bronchitic symptom in the present study. Snoring, apnoea and liability to 'nod off' during activity were much more common in the bronchitic group in both men and women, and most common in men, as expected. Snoring was reported by 29% of the men in the bronchitic group and by 14% in the reference group. In women, the corresponding figures were 14 and 8%, respectively, and for apnoea, the figures were 25 vs. 11% in men and 6 vs. 4% in women. The prevalence of OSAS symptoms was similar in subjects with attacks of breathlessness, long-standing cough, sputum production and recurrent wheezing. Bronchitic symptoms may influence quality of sleep and contribute to daytime tiredness, but this does not fully explain the high prevalence of snoring and apnoea reported by subjects in this cohort. This study indicates a positive correlation between chronic bronchitis and OSAS, but sleep studies are required to confirm this.

Dopamine-related genes and their relationships to monoamine metabolites in CSF

Monoamine metabolite (MM) levels in lumbar cerebrospinal fluid (CSF) are extensively used as indirect estimates of monoamine turnover in the brain. In this study we investigated genotypes for DNA polymorphisms in the D2 (DRD2), D3 (DRD3), and D4 (DRD4) dopamine receptor and tyrosine hydroxylase (TH) genes and their relationships to CSF MM in healthy volunteers (n = 66). Concentrations of homovanillic acid (HVA), 3-methoxy-4-hydroxyphenylglycol (MHPG), and 5-hydroxyindoleacetic acid (5-HIAA) were corrected for back length, a confounding variable. Corrected MM levels were not related to age, gender, height, weight heredity, season or atmospheric pressure at sampling. Individuals with specific DRD2 and TH allele and genotype configurations significantly differed in HVA and MHPG concentrations. DRD3 homo- and heterozygotic genotypes had significantly different CSF 5-HIAA levels. DRD4 genotypes were not related to MM concentrations. The results suggest that specific DRD2, DRD3, and TH genotypes participate in the regulation of monoamine turnover in the central nervous system. Accordingly monoamine receptors and synthesizing enzyme genotypes appear to be variance factors influencing MM concentrations in CSF. The relationships found in this study support MM concentrations as markers for monoamine transmission in the human brain.

[Important current genetic findings in schizophrenia]

Twin and adoption studies have yielded convincing evidence of the involvement of genetic factors in the aetiology of schizophrenia. A genetic link with chromosome 6 reported just over a year ago has since been confirmed by other research groups. There is reason to hope that one or more schizophrenia genes will be identified in the next few years.

Growth hormone increases predation exposure of rainbow trout

The energetic state of an animal strongly influences decisions that balances feeding against predation risk. Growth hormone increases the metabolic demands, which should elevate the feeding motivation of an animal. This, in turn, may increase the willingness to risk exposure to predators during feeding. To test this hypothesis, we studied the effect of growth hormone on the behavioural response of rainbow trout (Oncorhynchus mykiss) to simulated attacks from a model heron. After attacks, growth hormone treated trout foraged closer to the water surface, resumed feeding earlier, and ate more food than did control trout. Such behaviour should increase the susceptibility to aerial predation. Thus, predation may select against high endogenous growth hormone secretion in wild fish. Furthermore, genetic manipulations to increase growth hormone levels, intended to improve growth performance in aquaculture, may result in individuals with substantially altered behavioural patterns. In light of the increasing potential for interactions between farmed and wild fish, growth hormone transgenic fish may pose a threat to wild fish populations.

Dominance, nutritional state, and growth hormone levels in rainbow trout (Oncorhynchus mykiss)

This study addressed three questions concerning interactions between physiology and dominance in juvenile rainbow trout: (1) the validity of a model predicting a time-dependent effect of fasting on competitive ability (i.e., the ability to obtain contested food items) was tested in a series of dominance trials between fed and progressively more fasted trout, as was (2) the association between fasting and plasma growth hormone levels. (3) The relationship between plasma growth hormone levels and the competitive ability of individual trout was also studied. The main results were as follows: (1) The predictions of the time-dependent model were supported by the fasting-dominance experiment. After 3 days, fasted fish were dominant over fed fish, whereas after 6 and 9 days, the competitive ability of fed and fasted fish was similar. After 12 days, there was a tendency for fed fish to be dominant over their fasted competitors. (2) Sampling of plasma from fed and fasted trout, after 3, 6, 9, and 12 days, demonstrated that plasma growth hormone levels increases in food-deprived rainbow trout after more than 6 days of fasting, which is consistent with previous work. (3) No difference in plasma growth hormone levels was found between paired dominant and subordinate trout. Possible interactions between nutritional state, growth hormone levels, and dominance, and their implications are discussed.

A search for association between schizophrenia and dopamine-related alleles

Dopamine receptor dysfunction and altered tyrosine hydroxylase activity have both been implicated in the pathophysiology of schizophrenia. Schizophrenic patients and control subjects were examined for allele frequencies in the tyrosine hydroxylase and dopamine D2 and D4 receptor genes. No significant differences of allele or genotype frequencies were found between the two groups after adjustment for multiple comparisons. Neither were any significant relationships observed between allele frequencies and a number of clinical variables within the schizophrenic subsample. When no adjustment was made for multiple testing a few significant tendencies were obtained which warrant further research in extended patient and control materials. The results are compatible with the view that the tyrosine hydroxylase, dopamine receptor D2 and D4 gene polymorphisms examined are not of major importance in the aetiology or pathophysiology of schizophrenia.

Lack of association between schizophrenia and the apolipoprotein E epsilon 4 allele

The association between the epsilon 4 allele of the apolipoprotein E (APOE) gene and Alzheimer's disease (AD) has been reported. In order to examine if the epsilon 4 allele may play a role also in schizophrenia, another mental disorder, patients (n = 87) and control subjects (n = 57) were genotyped for APOE. No significant difference was found between the groups. The data indicate that the APOE gene is not of major importance for the genesis of schizophrenia.

Lack of association between alcohol-dependence and D3 dopamine receptor gene in three independent samples

Numerous studies on the involvement of dopamine receptors in the genetics of alcoholism focused on associations between a polymorphism of the D2 dopamine receptor (DRD2) gene and alcohol dependence. However, the results of these studies are conflicting. Another receptor, the D3 dopamine receptor (DRD3), may be of additional interest since it is specifically located in the limbic area, and in particular in the nucleus accumbens which plays a significant role in the reward process of addiction behavior. We thus tested the association in three independent samples of alcoholic patients, with different origins and various inclusion criteria. No difference in the DRD3 gene polymorphism emerged between controls and alcoholic patients, regardless of their origin, inclusion criteria, or presence or absence of the DRD2 TaqI A1-allele. Despite the fact that more information could have been considered and that association studies provide limited information, there is good evidence that this DRD3 polymorphism does not play a major role in the genetic component of alcoholism.

Decline of herpes simplex virus type 2 and Chlamydia trachomatis infections from 1970 to 1993 indicated by a similar change in antibody pattern

Antibodies to herpes simplex virus type 2 (HSV-2) and Chlamydia trachomatis (Ct) were determined in sera from pregnant women from 1970 and at intervals up to 1993. The trends for HSV-2 and Ct infections were deduced from the observed antibody rates in different age groups during the observation period. Total antibody rates for HSV-2 tended to decline toward the end of the period when age-matched groups were compared, while the Ct antibody rates peaked in 1979 and then declined gradually. Age-specific antibody rates showed declining frequencies in women younger than 20 years for both HSV-2 and Ct over the study period. Women 35 years of age and older in the early 1990s had significantly higher antibody rates than younger women at that time or than women of similar age in the early 1970s. This group of slightly older women with high antibody rates in the 1990s were 15-20 years of age in 1970 when a high antibody frequency was noted in this age group. High antibody rates against both HSV-2 and Ct in older pregnant women in the early 1990s may thus reflect a high incidence of these infections around 1970. The declining rates of antibodies in the youngest women would suggest a declining incidence of primary infections in this group.

Screening for CGG trinucleotide repeat expansion in the fragile X mental retardation 1 gene in schizophrenic patients

Patients diagnosed using DSM-III-R criteria as having schizophrenia and other related disorders (n = 128) were assessed for CGG trinucleotide repeat expansion in the fragile X mental retardation 1 (FMR-1) gene. One subject, a woman with schizophreniform disorder, was found to have a premutation of the gene. Her case report is given. The present investigation supports the view that mutation or premutation of the FMR-1 gene is not of importance for the aetiology of the vast majority of schizophrenic patients.

A set of male monozygotic triplets with schizophrenic psychoses: nature or nurture?

A set of schizophrenic male monozygotic triplets is described. At age 20 years, within 8 months the three men independently developed acute fulminant schizophrenic disorders (DSM-III-R) with auditory hallucinations, bizarre delusions, and thought disturbances. There were also great similarities between the triplets with regard to the chronic intermittent course of the disorder, impairment of social adjustment, and loss of working ability. The psychoses responded rapidly to conventional neuroleptic treatment. Neuropsychological assessment demonstrated similar marked reductions of attentional, mnestic, and executive functions. Magnetic resonance imaging (MRI) showed similar borderline ventricular enlargement and widened subarachnoid spaces over frontoparietal and basal regions as well as around the pituitary gland (empty sella). All the boys also had a right-sided hearing defect with a marked reduction of the ossicular bones on the right side. Possible clues as to etiological mechanisms were the lack of reported family history for the disorder and a possible influenza infection in the mother during the first trimester. It is suggested that a DNA aberration being present or occurring at conception initiated a precise time-programmed series of events that produced the very similar schizophrenic phenotypes. Such an aberration might have been induced by an external agent, occurred spontaneously, or been inherited by a recessive mechanism. It seems possible that the psychoses, the reductions of neuropsychological functions, the morphological MRI changes, and the right-sided ossicular reductions may all be related to such a DNA alteration.

Prevalence of positive skin prick tests, allergic asthma, and rhinoconjunctivitis in teenagers in northern Sweden

The prevalence of positive skin prick tests (SPT) for common allergens and symptoms of allergic rhinoconjunctivitis or asthma was investigated in Umeå in northern Sweden in 1987. Skin prick tests with 10 allergens common in Sweden and a questionnaire were used to examine 1112 teenagers. All subjects with a positive skin prick test or symptoms were interviewed, and they were further investigated by a serum specific IgE test, a ventilatory lung function test, and a physical examination. At least one skin prick test was positive in 43% of the subjects. Ninety-three percent had at least one positive skin prick test to one of the three most common allergens: cat, timothy grass, and birch. The prevalence of current allergic rhinoconjunctivitis was 17%, current allergic asthma 2.8%, and current asthma (both allergic and nonallergic) 6.8%. Multiple logistic regression analysis showed that the most important risk factors for current asthma were sex (being a girl) and atopy. Heredity of asthma or rhinoconjunctivitis and being born in the winter (October-March) also increased the risk. In atopic subjects, having a mother who smoked and heredity of asthma increased the risk. For allergic rhinoconjunctivitis, heredity increased the risk of getting rhinoconjunctivitis.

Timing of facial osteotomies. A consensus conference

A concensus conference on the timing of facial osteotomies was held in Jönköping, Sweden. Seven teams consisting of a maxillofacial surgeon and an orthodontist representing five countries discussed treatment planning for young patients with maxillomandibular deformities with special emphasis on timing. Patients with severe syndromic facial deformities were not considered. Consensus was reached that for most deformities it is best advised to wait until growth has ceased, as determined by longitudinal cephalometric data. This rule is less tight for Angle Class II than for Class III cases. For asymmetries often there is still not enough scientific evidence to obtain well-founded uniform agreement.

Epidemiology of respiratory symptoms, lung function and important determinants. Report from the Obstructive Lung Disease in Northern Sweden Project

SETTING

Cross-sectional epidemiological study based on a representative sample of the general population in northern Sweden.

OBJECTIVES

To assess the prevalence of respiratory symptoms, the role of respiratory symptoms as indicators of impairment of lung function, and to define risk factors for respiratory symptoms and lung function impairment.

DESIGN

The 1340 subjects of 6610 who reported respiratory symptoms suggestive of asthma or chronic bronchitis in a postal questionnaire study were invited to a structured interview and lung function tests. A control group of 315 subjects was also invited. Risk factors were assessed from the postal questionnaire.

RESULTS

400 subjects in the symptomatic group had attacks of breathlessness and wheezing, while none in the control group had them, corresponding to 7% of the original study population. Chronic productive cough was present in 537 subjects, of whom 13 were from the control group, suggesting that 12% of the original study population had this symptom. Persistent wheeze was the symptom that predicted the greatest proportion of cases of impaired lung function. Attacks of breathlessness, wheezing, long-standing cough and sputum production were all related to age, smoking and a family history of asthma. Both chronic productive cough and impaired lung function correlated strongly with smoking and age, and their prevalences differed in different socio-economic groups.

CONCLUSION

Impaired lung function can be predicted from respiratory symptoms. Data collected in postal questionnaires suffice for the identification of risk factors. Combinations of symptoms gave greater odds ratios than individual symptoms.

Dopamine D2-receptor gene polymorphisms in Scandinavian chronic alcoholics

Alterations in the dopamine system have been hypothesized as a predisposing factor in alcoholism. The presence of the TaqI A1 and B1 alleles adjacent to the dopamine D 2-receptor gene (DRD2) was studied in Scandinavian alcoholic inpatients (n = 74), alcoholics autopsied at a forensic clinic (n = 19) and controls (n = 81). There were no significant differences between controls and the alcoholics, but a tendency of increased DRD2 TaqI A1 or B1 allele frequencies in alcoholic groups selected for severity (i.e. severity according to DSM-III-R criteria, early onset or severe medical complications due to alcohol abuse) and decreased frequencies in the corresponding less severe alcoholic group. The present study does not yield evidence for the hypothesis of an association between the DRD2 TaqI A1 or B1 alleles and alcoholism.

Lack of association between schizophrenia and alleles in the dopamine D3 receptor gene

Dopamine receptor dysfunction has been implicated in the pathophysiology of schizophrenia. Schizophrenic patients (n = 76) and control subjects (n = 53) were examined for allele frequencies in a 2-allele BalI polymorphism, causing a serine-->glycine amino acid substitution in the coding sequence of the dopamine D3 receptor gene. No statistical significant differences of allele frequencies or genotype frequencies could be found between the two groups. Neither were there any significant relationships between allele frequencies and a number of clinical variables within the schizophrenic subsample. However, if not corrected for multiple testing, an association was found between homozygosity and positive response to neuroleptic drugs. The present study does not provide evidence that the BalI polymorphism in the dopamine D3 receptor gene is involved in the pathophysiology of schizophrenia. Further investigations with an increased number and variety of patients concerning response to neuroleptic drugs and expression of the receptor in human brain should be performed to definitively exclude this hypothesis.

Methacholine reactivity and asthma. Report from the Northern Sweden Obstructive Lung Disease Project

Methacholine tests were used in an epidemiologic study of the prevalence of asthma and chronic bronchitis in northern Sweden. Of 6610 subjects in three age groups from eight representative geographic areas in the northernmost province of Sweden, 5698 (86%) completed a postal questionnaire on respiratory symptoms, and 1506 underwent a structured interview and a lung function test. A total of 292 (5%) were diagnosed as having asthma. A subsample of 284 subjects (of 320 invited) classified at the interview as having asthma (n = 98) or as having respiratory symptoms that might be due to asthma but not fulfilling the interview criteria for the diagnosis of asthma (n = 186) underwent a methacholine test. Subjects who, before the interview study, already had a well-defined asthma diagnosis were not invited to the methacholine testing. Of those 98 subjects classified as having asthma, 61% reacted to methacholine doses < or = 4 mg/ml and 79% to doses < or = 8 mg/ml, while the corresponding figures in the symptomatic but nonasthma group were 20% and 34%, respectively. The results show that a carefully performed structured interview accurately diagnoses asthma in epidemiologic studies. The methacholine tests provide important diagnostic information primarily in subjects in whom the medical history is equivocal.

Influence of dietary fat, cholesterol and energy on serum lipids at vigorous physical exercise

Seven healthy male volunteers participated in four different heavy cross-country ski trips in the mountains, 1 year apart, wearing a back-pack weighing 30 kg. Each trip lasted for 8 days covering a total distance of 160 km. Serum triglycerides and lipoprotein cholesterol were measured before and after the trip. The different experiments were carried out with the same participants and under the same conditions, but with a varying diet composition. With the four different diets used, a standard diet (3800 kcal day-1, 26% fat, 260 mg cholesterol day-1), a low-energy diet (2300 kcal day-1, 21% fat, 110 mg cholesterol day-1, a high-fat-high-cholesterol diet (3800 kcal day-1, 52% fat, 480 mg cholesterol day-1) and a high-cholesterol diet (3800 kcal day-1, 29% fat, 410 mg cholesterol day-1), a decrease in very low-density lipoprotein-low-density lipoprotein (VLDL-LDL) fraction by 38%, 50%, 41%, and 54%, respectively, was obtained. No significant increase in high-density lipoprotein (HDL) cholesterol was found in the experiments with the standard diet and the low-energy diet, but in the high-fat-high-cholesterol diet experiment the HDL cholesterol increased by 19% and the ratio HDL cholesterol:total cholesterol from 0.327 to 0.490. With the high-cholesterol diet an increase in HDL cholesterol of about the same extent was obtained. In all experiments the serum triglycerides decreased by more than 30% and no significant difference for the different diets was obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Traumatic neuroma following sagittal mandibular osteotomy

A case of painful traumatic neuroma, arising from the inferior alveolar nerve after sagittal osteotomy of the mandible with demonstrable radiological change, is reported. The co-existence of temporomandibular joint (TMJ) pain-dysfunction syndrome and a painful traumatic neuroma had posed diagnostic problems. Some modifications of the surgical technique are discussed with a view to minimizing damage to the inferior alveolar nerve during sagittal osteotomy of the mandible. The aetiology, clinical features, diagnosis and treatment of traumatic neuromas are reviewed.