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L A Laitinen

Publications and source records attributed to L A Laitinen.

At least 19 recordsLinked to original sources
PubMed2006

Predictors of COPD symptoms: does the sex of the patient matter?

Although chronic obstructive pulmonary disease (COPD) patients frequently report symptoms, it is not known which factors determine the course of symptoms over time and if these differ according to the sex of the patient. The current study investigated predictors for presence, development and remission of COPD symptoms in 816 males and 312 females completing 3-yr-follow-up in the European Respiratory Society Study on Chronic Obstructive Pulmonary Disease (EUROSCOP). The following were included in generalised estimating equations logistic regression analyses: explanatory variables of treatment; pack-yrs smoking; age, forced expiratory volume in one second % predicted (FEV1 % pred); annual increase in FEV1 and number of cigarettes smoked; body mass index; and phadiatop. Interaction terms of sex multiplied by explanatory variables were tested. Over 3 yrs, similar proportions of males and females reported symptoms. In males only, higher FEV1 % pred was associated with reduction in new symptoms of wheeze and dyspnoea, and symptom prevalence was reduced with annual FEV1 improvement and phlegm prevalence reduced with budesonide treatment (odds ratio 0.66; 95% confidence interval 0.52-0.83). Additionally an increase in the number of cigarettes smoked between visits increased the risk of developing phlegm (1.40 (1.14-1.70)) and wheeze (1.24 (1.03-1.51)) in males but not females. The current study shows longitudinally that symptom reporting is similar by sex. The clinical course of chronic obstructive pulmonary disease can differ by sex, as males show greater response to cigarette exposure and treatment.

Adult↗
PubMed2006

A 10 year asthma programme in Finland: major change for the better.

BACKGROUND: A National Asthma Programme was undertaken in Finland from 1994 to 2004 to improve asthma care and prevent an increase in costs. The main goal was to lessen the burden of asthma to individuals and society. METHODS: The action programme focused on implementation of new knowledge, especially for primary care. The main premise underpinning the campaign was that asthma is an inflammatory disease and requires anti-inflammatory treatment from the outset. The key for implementation was an effective network of asthma-responsible professionals and development of a post hoc evaluation strategy. In 1997 Finnish pharmacies were included in the Pharmacy Programme and in 2002 a Childhood Asthma mini-Programme was launched. RESULTS: The incidence of asthma is still increasing, but the burden of asthma has decreased considerably. The number of hospital days has fallen by 54% from 110 000 in 1993 to 51 000 in 2003, 69% in relation to the number of asthmatics (n = 135 363 and 207 757, respectively), with the trend still downwards. In 1993, 7212 patients of working age (9% of 80 133 asthmatics) received a disability pension from the Social Insurance Institution compared with 1741 in 2003 (1.5% of 116 067 asthmatics). The absolute decrease was 76%, and 83% in relation to the number of asthmatics. The increase in the cost of asthma (compensation for disability, drugs, hospital care, and outpatient doctor visits) ended: in 1993 the costs were 218 million euro which had fallen to 213.5 million euro in 2003. Costs per patient per year have decreased 36% (from 1611 euro to 1031 euro). CONCLUSION: It is possible to reduce the morbidity of asthma and its impact on individuals as well as on society. Improvements would have taken place without the programme, but not of this magnitude.

Adult↗
PubMed2005

Predictors of lung function and its decline in mild to moderate COPD in association with gender: results from the Euroscop study.

BACKGROUND: There is increasing appreciation of gender differences in COPD but scant data whether risk factors for low lung function differ in men and women. We analysed data from 3 years follow-up in 178 women and 464 men with COPD, participants in the Euroscop Study who were smokers unexposed to inhaled corticosteroids. METHODS: Explanatory variables of gender, age, starting age and pack-years smoking, respiratory symptoms, FEV(1)%FVC and FEV(1)%IVC (clinically important measures of airway obstruction), body mass index (BMI), and change in smoking were included in multiple linear regression models with baseline and change in post-bronchodilator FEV(1) as dependent variables. RESULTS: Reduced baseline FEV(1) was associated with respiratory symptoms in men only. Annual decline in FEV(1) was not associated with respiratory symptoms in either men or women, and was 55 ml less in obese men (BMI 30 kg/m(2)) than men having normal BMI, an effect not seen in women. It was 32 ml faster in women with FEV(1)%FVC<median than women with less airway obstruction, a larger difference than in men (8 ml per year). It was 17.7 ml/year faster when increasing the daily number of cigarettes by 10 in men only, but not significantly greater than in women. CONCLUSION: Respiratory symptoms were associated with reduced baseline FEV(1) in men with COPD. In men, obesity was associated with reduced decline and increasing the number of cigarettes smoked with increased decline in lung function. In women more severe airway obstruction was associated with accelerated decline.

Adult↗
PubMed2004

Association study of 15 novel single-nucleotide polymorphisms of the T-bet locus among Finnish asthma families.

OBJECTIVE: T-box expressed in T cells (T-bet) is a transcription factor regulating the commitment of T helper (Th) cells by driving the cells into the Th1 direction. Abnormal Th1/Th2 balance may lead to complex disorders like asthma or autoimmune diseases. Recent studies have suggested that T-bet might be a candidate gene for asthma. This led us to screen 23 Finnish individuals for single-nucleotide polymorphisms (SNPs) in the T-bet locus and study the association between the SNPs and high serum IgE level and asthma. METHODS: We screened all six exons, adjacent intronic areas and 2 kb of the 5'-flanking region from 23 individuals utilizing WAVE trade mark technology. To explore whether T-bet is associated in serum IgE regulation or asthma we genotyped the SNPs in a Finnish asthmatic founder population. The association analyses were made using haplotype pattern mining. RESULTS: Fifteen novel SNPs were found in the T-bet gene. Within the Finnish asthmatic founder population, there was no association between T-bet SNPs and high serum IgE level or asthma. CONCLUSIONS: The genetic variability in the T-bet gene does not play a role in the pathogenesis of human asthma. Our results provide a novel panel of SNPs in T-bet and will help determine whether the SNPs have a functional role in other T cell-mediated diseases.

Asthma↗
PubMed2003

Airway inflammation and basement membrane tenascin in newly diagnosed atopic and nonatopic asthma.

Previous studies have shown both similar and distinct inflammatory changes in atopic and nonatopic asthma. This study was set to investigate the bronchial inflammatory cell infiltrate and subepithelial basement membrane (BM) tenascin deposition in subjects with newly diagnosed asthma and bronchial hyperresponsiveness (BHR). Seventy-nine asthmatic subjects (age 18-60 years) were recruited and 58 were atopic according to skin prick testing. The patients recorded asthma symptoms and peak flow measurements for 14 days. Lung function and BHR were measured by spirometry and histamine challenge. Serum eosinophil cationic protein (ECP) and blood eosinophils were assessed. Fiberoptic bronchoscopy was performed to obtain bronchial biopsies. Serum ECP was higher in the atopic group but eosinophil counts did not differ. There were no differences in inflammatory cells studied (activated eosinophils, T-lymphocytes, mast cells or macrophages) between nonatopic and atopic subjects. BM tenascin layer was significantly thicker in atopic compared with nonatopic subjects (7.6 vs 6.3 microm, P = 0.007). The thickness of tenascin correlated with eosinophil, T-lymphocyte, and macrophage counts, as well as with IL-4-positive cell counts and the correlation was seen only in atopic asthmatics. These findings suggest that inflammatory cells may have a regulatory role in tenascin expression in atopic asthma.

Adult↗
PubMed2003

Sleep apnoea: Finnish National guidelines for prevention and treatment 2002-2012.

(1) After negotiations with the Finnish Ministry of Social Affairs and Health, a national programme to promote prevention, treatment and rehabilitation of sleep apnoea for the years 2002-2012 has been prepared by the Finnish Lung Health Association on the basis of extensive collaboration. The programme needs to be revised as necessary, because of the rapid development in medical knowledge, and in appliance therapy in particular. (2) Sleep apnoea deteriorates slowly. Its typical features are snoring, interruptions of breathing during sleep and daytime tiredness. Sleep apnoea affects roughly 3% of middle-aged men and 2% of women. In Finland, there are approx. 150,000 sleep apnea patients, of which 15,000 patients have a severe disease, 50,000 patients are moderate and 85,000 have a mild form of the disease. Children are also affected by sleep apnea. A typical sleep apnea patient is a middle-aged man or a postmenopausal woman. (3) The obstruction of upper airways is essential in the occurrence of sleep apnoea. The obstruction can be caused by structural and/or functional factors. As for structural factors, there are various methods of intervention, such as to secure children's nasal respiration, to remove redundant soft tissue, as well as to correct malocclusions. It is possible to have an effect on the functional factors by treating well diseases predisposing to sleep apnoea, by reducing smoking, the consumption of alcohol and the use of medicines impairing the central nervous system. The most important single risk factor for sleep apnoea is obesity. (4) Untreated sleep apnoea leads to an increase morbidity and mortality through heart circulatory diseases and through accidents by tiredness. Untreated or undertreated sleep apnoea deteriorates a person's quality of life and working capacity. (5) The goals of the Programme for the prevention and treatment of sleep apnoea are as follows: (1) to decrease the incidence of sleep apnoea, (2) to ensure that as many patients as possible with sleep apnoea recover, (3) to maintain capacity for work and functional capacity of patients with sleep apnoea, (4) to reduce the percentage of patients with severe sleep apnoea, (5) to decrease the number of sleep apnoea patients requiring hospitalisation and (6) to improve cost effectiveness of prevention and treatment of sleep apnoea. (6) The following means are suggested for achieving the goals: (1) to promote prevention of obesity, weight loss and weight control; (2) to promote securing of nasal respiration in child patients and removal of obstructing redundant soft tissues; (3) to promote the correction of children's malocclusions, (4) to enhance knowledge about risk factors and treatment of sleep apnoea in key groups, (5) to promote early diagnosis and active treatment, (6) to commence rehabilitation early and individually as a part of treatment and (7) to encourage scientific research. (7) On the national level, the occurrence of sleep apnoea can be prevented, for example, by encouraging weight control. The programme gives examples of such measures and appeals to various authorities and voluntary organisations to reinforce their collaboration. Preventive measures should be individualised, and based on due consideration. (8) The efficacy of diagnosing sleep apnoea should be increased. Attention should be paid to the symptoms of risk group patients at different units of the primary and occupational health care. Even mild forms of the disease should be treated appropriately. Diagnosis and treatment of the disease involve cooperation between the primary and specialised health-care sectors. Methods of treatment are (1) treatment of obesity, (2) positional therapy, (3) reduction of the use of medicines impairing the central nervous system, (4) reduction of smoking and the consumption of alcohol, (5) devices affecting the position of the tongue and lower jaw, (6) treatment with Continuous Positive Airway Pressure (CPAP-treatment), (7) surgical methods of treatment and (8) rehabilitation. (9) The hierarchy of referrals in the prevention and treatment of sleep apnoea should be revised to accord a greater role to the primary health-care sector. Good exchanges of information and cooperation between the primary health care and specialised medical-care sectors should be developed. Hospitals districts in cooperation with provincial governments and municipalities should ensure that different levels of the health-care system are capable of fulfilling the tasks assigned to them appropriately. (10) Rehabilitation of sleep apnoea should be goal-orientated and cover all forms of rehabilitation: medical, occupational and social. Rehabilitation should prevent the effects caused by the disease. Thus, it is possible to support self-care, increase the patient's resources and improve quality of life. (11) Information and training should be directed primarily towards health-care personnel, patients and their families. Organisations should produce materials for health and patient education as well as organising training events. To support the activities. financing will be needed from organisations such as Finland's Slot Machine Association. The Social Insurance Institution should disseminate information about questions of social security. Regional direction and training will mainly be the responsibilities of hospital districts, provincial governments and local health centres. The media will play an important role in the dissemination in-depth information about prevention and treatment of sleep apnoea.

Child↗
PubMed2003

Sustained reduction in bronchial hyperresponsiveness with inhaled fluticasone propionate within three days in mild asthma: time course after onset and cessation of treatment.

BACKGROUND: Bronchial hyperresponsiveness (BHR) is characteristic of asthmatic airways, is induced by airway inflammation, and is reduced by inhaled corticosteroids (ICS). The time course for the onset and cessation of the effect of ICS on BHR is unclear. The effect of inhaled fluticasone propionate (FP) on BHR in patients with mild persistent asthma was assessed using time intervals of hours, days and weeks. METHODS: Twenty six asthmatic patients aged 21-59 years were selected for this randomised, double blind, parallel group study. The effect of 250 micro g inhaled FP (MDI) administered twice daily was compared with that of placebo on BHR assessed using a dosimetric histamine challenge method. The dose of histamine inducing a decrease in forced expiratory volume in 1 second (FEV(1)) by 15% (PD(15)FEV(1)) was measured before and 6, 12, 24 and 72 hours, and 2, 4 and 6 weeks after starting treatment, and 48 hours, 1 week and 2 weeks after cessation of treatment. Doubling doses of changes in PD(15)FEV(1) were calculated and area under the curve (AUC) statistics were used to summarise the information from individual response curves. RESULTS: The increase in PD(15)FEV(1) from baseline was greater in the FP group than in the placebo group; the difference achieved significance within 72 hours and remained significant until the end of treatment. In the FP group PD(15)FEV(1) was 1.85-2.07 doubling doses above baseline between 72 hours and 6 weeks after starting treatment. BHR increased significantly within 2 weeks after cessation of FP treatment. CONCLUSIONS: A sustained reduction in BHR to histamine in patients with mild asthma was achieved within 3 days of starting treatment with FP at a daily dose of 500 micro g. The effect tapered within 2 weeks of cessation of treatment.

Administration, Inhalation↗
PubMed2002

Investigative bronchoscopy and endobronchial biopsy is well tolerated in hyperreactive asthma patients.

The tolerability of 57 non-smoking asthma patients inhaling salbutamol as needed (ATS, 18--60 years, 60% < or = FEV1 < or =100%, PD15FEV1 <0.4 mg histamine) to fibreoptic bronchoscopy (FOB) and endobronchial biopsy was studied. The FOB was done in local Lignocaine anaesthesia, and from five to eight biopsy specimens were taken from the bronchial mucosa of the right lung. The tolerability was measured as cough/bronchospasm during the procedure (from 0 = normal to 3 = interrupted procedure), success of the procedure, and untoward occurrences. Twenty-seven of the 57 patients (48%) had no cough or bronchospasm during the FOB (score 0). Few coughs of no importance (score 1) were documented in 23 patients (40%). Seven patients (12%) had cough and/or bronchospasm interfering with the FOB procedure (score 2). The FOB procedure was not interrupted because of cough and/or bronchospasm (score 3) in any patient. Scores of cough and/or bronchospasm diminished progressively with the increase of PD15FEV1 histamine. The success of the procedure was 100%. Two patients had untoward medical occurrences requiring additional rescue medication (3.5%). In conclusion, we found that hyperreactivity predicts cough and/or bronchospasm during the FOB. Cough and/or bronchospasm are frequently observed during the bronchial procedure, but they are mild and of minor clinical importance. An investigational endobronchial procedure can be successfully performed in mildly or moderately obstructive asthmatic patients, even in cases with severe bronchial hyperreactivity.

Adolescent↗
PubMed2002

Prevalence and risk factors for asthma and chronic bronchitis in the capitals Helsinki, Stockholm, and Tallinn.

The aim of this part of the FinEsS-studies was to assess whether differences existed in prevalence of asthma, chronic bronchitis, and respiratory symptoms between three Baltic capitals, and to examine risk factor profiles for respiratory conditions. In 1996, a postal survey was performed in these cities with a response rate of 72% in Stockholm, 76% in Helsinki, and 68% in Tallinn. The prevalence of physician-diagnosed asthma was 76% in Stockholm, 6.2% in Helsinki, and 2.3% in Tallinn, while respiratory symptoms were most common in Tallinn. The prevalence of physician-diagnosed chronic bronchitis was 10.6% in Tallinn, 3.4% in Helsinki, and 3.0% in Stockholm. Risk factor analyses revealed a significantly increased risk for those living in Tallinn compared to that of Stockholm for wheezing conditions, OR 1.56-1.69, longstanding cough, OR 1.92 (1.74-2.13), attacks of shortness of breath during the previous 12 months, OR 1.35 (1.20-1.52), and chronic productive cough, OR 1.49 (1.28-1.74). Subjects having symptoms common in asthma were more likely to have physician-diagnosed asthma in Stockholm and Helsinki than in Tallinn, while subjects having bronchitis symptoms had more often physician-diagnosed chronic bronchitis in Tallinn. Prevalence of respiratory symptoms was higher in Tallinn than in Stockholm and Helsinki, while physician-diagnosed asthma was more common in Stockholm and Helsinki. The prevalence of physician-diagnosed chronic bronchitis was three times as high in Tallinn as in Helsinki or Stockholm. Our results also suggest large differences in diagnostic practices between the three countries, while the differences between the capitals in true prevalence of disease may be small.

Adult↗
PubMed2002

Short-term variability of exhaled nitric oxide in young male patients with mild asthma and in healthy subjects.

BACKGROUND: Exhaled nitric oxide (NOexp) is an indicator of eosinophilic airways inflammation. This study evaluated short-term variability of NOexp in 13 healthy subjects (19-41 years, eight males) and in 31 patients with asthmatic respiratory symptoms (19-21 years, all male) to obtain data for assessment of short-term changes of NOexp in clinical situations. METHODS: Mild asthma was confirmed in 10 patients (Group = asthma). Twenty-one patients with asthmatic respiratory symptoms did not fulfill the functional criteria of asthma (Group = respiratory symptoms). The procedure to determine NOexp followed the European Respiratory Society (ERS) guidelines; the mean expiratory flow used during sampling was 0.09-0.12 l/s. NOexp for each subject was determined as the mean of at least three successive measurements at the baseline, followed by determinations at 10 min, 6 h and 24 h after the baseline. RESULTS: At the baseline, the mean (SD) value of NOexp was 6.6 (2.3) parts per billion (ppb) in the healthy controls, and significantly higher both in patients with respiratory symptoms (14.6 (11) ppb, P = 0.0076) and in those with asthma (34.2 (43) ppb, P < 0.001). Intraclass correlation coefficient of NOexp measured at baseline and after an interval of 10 min was 0.959 in healthy subjects, 0.986 in patients with respiratory symptoms and 0.936 in asthma patients, respectively. Short-term variability in terms of coefficient of variation (CoV) of repeated measurements of NOexp at 10 min, 6 hand 24 h was 5.1, 10.8 and 11.7% in healthy subjects, 71, 16.4 and 22.2% in patients with respiratory symptoms and 13.5, 19.4 and 26.4% in asthma patients, respectively. CONCLUSIONS: Reproducibility of NOexp using standardized methods was good both in healthy subjects and in asthmatic patients. However, in asthmatics the short-term variation of NOexp was over two times as high as in healthy subjects. The level of NOexp was elevated, except in asthma, also in patients with asthmatic respiratory symptoms who did not fulfill the functional criteria of asthma.

Adult↗
PubMed2002

Bone mineral density in patients with chronic obstructive pulmonary disease treated with budesonide Turbuhaler.

There is a need for studying the effects of long-term inhaled corticosteroid therapy on bone mineral density (BMD) and vertebral fracture rates in patients with mild chronic obstructive pulmonary disease (COPD). Patients (n=912, mean age 52 yrs) with mild COPD (mean forced expiratory volume in one second (FEV1) 77% of predicted; mean FEV1/slow vital capacity ratio 62%) were randomized to receive budesonide 400 microg, or placebo twice daily via Turbuhaler. BMD was measured at the L2-L4 vertebrae and the femoral neck, trochanter and Ward's triangle by dual-energy X-ray absorptiometry at baseline and after 6, 12, 24 and 36 months (n=161). Radiographs of the thoracic and lumbar spine were obtained at the beginning and end of treatment (n=653). Previous fractures were present at baseline in 43 budesonide-treated patients (13.4%) and 38 placebo-treated patients (11.5%). New fractures occurred in five budesonide-treated patients, compared with three in the placebo group (p=0.50). There were no significant changes in BMD at any site in budesonide-treated patients, compared with the placebo group, during the course of the study. Budesonide treatment was associated with a slight but statistically significant decrease in the area under the concentration-time curve for serum osteocalcin. In the present study, involving a large group of patients with chronic obstructive pulmonary disease, long-term treatment with budesonide 800 microg x day(-1) via Turbuhaler had no clinically significant effects on bone mineral density or fracture rates.

Administration, Inhalation↗
PubMed2001

A second-generation association study of the 5q31 cytokine gene cluster and the interleukin-4 receptor in asthma.

We have analyzed a dense set of single-nucleotide polymorphisms (SNPs) and microsatellites spanning the T-helper cytokine gene cluster (interleukins 3, 4, 5, 9, and 13, interferon regulatory factor-1, colony-stimulating factor-2, and T-cell transcription factor-7) on 5q31 and the gene encoding the interleukin-4 receptor (IL4R) on 16p12 among Finnish families with asthma. As shown by haplotype pattern mining analysis, the number of disease-associated haplotype patterns differed from that expected for the 129Q allele polymorphism in IL13 for high serum total immunoglobulin (Ig) E levels, but not for asthma. The same SNP also yielded the best haplotype associations. For IL4R, asthma-associated haplotype patterns, most spanning the S411L polymorphism, showed suggestive association. However, these haplotypes consisted of the major alleles for the intracellular part of the receptor and were very common among both patients and controls. The minor alleles 503P and 576R have been reported to be associated with decreased serum IgE levels and changes in the biological activity of the protein, especially when inherited together. In the Finnish population, these two polymorphisms segregated in strong linkage disequilibrium. Our data support previous findings regarding L4R, indicating that 503P and 576R may act as minor protecting alleles for IgE-mediated disorders.

Alleles↗
PubMed2001

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.

Adult↗
PubMed2001

Increase of asthma in adults in northern Finland?--a report from the FinEsS study.

BACKGROUND: According to previous studies, the prevalence of asthma has been lower in Finland than in other Nordic countries. In the present study, we assessed the prevalence of asthma and respiratory symptoms in northern Finland and calculated risk factors for these conditions. METHODS: In November 1995, 7937 randomly selected subjects, 20-69 years of age, in northern Finland were invited to participate in a postal questionnaire survey. Complete answers were received from 6633 subjects (83.6%). RESULTS: Asthma diagnosed by a physician was reported by 6.0%, while 6.3% were using asthma medicines. Asthma was most common in young adults and the elderly. The prevalence of wheezing during the previous 12 months was reported by 19.7%, while wheezing with shortness of breath apart form colds during the previous 12 months was reported by 7.1%. Only small differences between the sexes were found in prevalence of asthma and respiratory symptoms. All symptoms were strongly smoking-dependent. Sixty-three percent of men and 42% of women were current or ex-smokers. Family history of obstructive airway disease was the strongest risk factor for asthma (OR 2.9), while increasing age, smoking, and family history of obstructive airway disease were the most important risk factors for frequent wheeze. CONCLUSIONS: The results indicate that the prevalence of asthma and symptoms associated with asthma in adults in northern Finland is now similar to that observed in Sweden and the other Nordic countries.

Adult↗
PubMed2001

A susceptibility locus for asthma-related traits on chromosome 7 revealed by genome-wide scan in a founder population.

The genetics of asthma and atopy have been difficult to determine because these diseases are genetically heterogeneous and modified by environment. The pedigrees in our study (n=86) originate in eastern central Finland (Kainuu province). According to census records, this region had only 200 households (2,000 inhabitants) in the mid sixteenth to mid seventeenth centuries. The current population of 100,000 represents the expansion of these founders within the past 400 years. Because this population is relatively homogeneous, we hypothesized that the molecular genetic mechanisms underlying asthma might also have reduced heterogeneity and therefore be easier to dissect than in mixed populations. A recent twin family study supported a strong genetic component for asthma in Finland. We carried out a genome-wide scan for susceptibility loci in asthma in the Kainuu subpopulation. We identified two regions of suggestive linkage and studied them further with higher-density mapping. We obtained evidence for linkage in a 20-cM region of chromosome 7p14-p15 for three phenotypes: asthma, a high level of immunoglobulin E (IgE; atopy) and the combination of the phenotypes. The strongest linkage was seen for high serum IgE (non-parametric linkage (NPL) score 3.9, P=0.0001), exceeding the threshold for genome-wide significance based on simulations. We also observed linkage between this locus and asthma or atopy in two independent data sets.

Asthma↗
PubMed2001

Social predictors of adult asthma: a co-twin case-control study.

BACKGROUND: Environmental factors are needed to explain the observed increase in the prevalence of asthma during recent decades, despite the existence of a recognised genetic component in asthma. A co-twin case-control study was undertaken to examine possible social risk factors for asthma. METHODS: Asthma diagnoses were based on register data of reimbursed asthma medication. During 17 years follow up of the Finnish twin cohort, 262 twin pairs discordant for incident asthma were identified. Conditional logistic regression for 1-1 matched data was used for risk calculation. RESULTS: The atopic twin had an increased risk of asthma compared with the non-atopic co-twin (RR 2.91, 95% CI 1.81 to 4.68). The more educated twin had a decreased risk of asthma compared with his/her twin sibling with less education (RR 0.45, 95% CI 0.23 to 0.86), and the twin who participated in conditioning exercise had a decreased risk of asthma compared with the more sedentary co-twin (RR 0.55, 95% CI 0.34 to 0.88). CONCLUSIONS: In addition to allergic diseases, educational level and physical activity are associated with adult onset asthma, which indicates a role for factors associated with life style.

Adult↗
PubMed2001

Perinatal risk factors for hay fever--a study among 2550 Finnish twin families.

Previous studies have suggested that perinatal factors influence the risk for asthma but population studies on perinatal factors and risk for hay fever are few. We studied the effect of perinatal factors on the risk for hay fever among adolescent twins by a questionnaire study involving five consecutive nation-wide birth cohorts of 16-year-old twins and their parents. The risk for parent-reported, doctor-diagnosed hay fever in the adolescents associated with several perinatal characteristics was assessed with logistic regression analysis among individuals and by a discordant pair analysis. In the univariate analysis of the birth factors, the risk for hay fever increased with increasing birth weight (p for trend = 0.048, OR for those > or = 3000 g 1.35, 95% CI 0.91-2.02 compared to those < 2000 g) and gestational age (p for trend = 0.04, OR for those born after 40 weeks of gestation 2.24, 95% CI 1.03-4.86, compared to those born before 33 weeks of gestation) and was lower in those subjects hospitalised in the neonatal period (OR 0.74, 95% CI 0.58-0.93). Because of significant interactions between parental hay fever status and birth factors (ponderal index, p = 0.03 and maternal age p = 0.04), stratified analysis were performed. The positive association between birth weight and hay fever was most obvious among adolescents with no parental history of hay fever (p for trend = 0.03). Similar, though not significant, trends were found with other birth factors among these families, whereas no such trend was found among adolescents with parental hay fever, suggesting that gestational maturity increases the risk for hay fever in the absence of genetic predisposition. However, of the perinatal factors only neonatal hospitalisation (OR 0.75, 95% CI 0.59-0.96) remained a significant risk factor for the development of hay fever, when adjusted for non-perinatal factors.

Adolescent↗