Modifiable risk factors for asthma control in adults: the HUNT study
Modifiable risk factors for asthma control in adults: the HUNT study In 2016 the overseas research stay at the Queensland Institute of Medical Research, Brisbane, finished at the end of February. This resulted in a publication titled “Multivariate eQTL mapping uncovers functional variation on the X-chromosome associated with complex disease traits” published in Human Genetics. This study found 548 indepented eSNPs on the X-chromosome. 35 of these were mapped to previously published disease- or trait-associated variants identified though GWAS. There were no eSNPs on the X-chromosome linked to asthma, however eSNPs were identified for type 1 diabetes, bilirubin levels and schizophrenia. In March, the Masters student completed her project titled “Sex differences in asthma control: The HUNT Study”. The student successfully completed the thesis with grade A and the work is being drafted for publication. The second study of the project titled “Physical activity and lung function decline in adults with asthma: The HUNT Study” was published (PMID: 27696634). In this study we found that physically active participants had slightly less lung function decline than inactive participants. The paper and results can be found online. Additionally, we investigated the association between physical activity and incident asthma in participants of the HUNT study. The study was called “Physical activity and incident asthma in adults: the HUNT Study, Norway”. In this study we found did not find any association between levels of physical activity and incident asthma in adults. The work from 2015 on the study titled “Vitamin D and Lung Function Decline in Adults With Asthma: The HUNT Study.” was also published. The study found that participants with low 25(OH)D (<50 nmol/L) had more decline in lung function than participants with higher levels of 25(OH)D. The associations were stronger in never smokers and non-ICS-users. The precision of the estimates however were generally weak. Earlier in the project we had problems defining a valid measure of asthma control and had decided to focus our efforts on lung function, a central component of asthma control. However in this second year we were able to create a reliable definition. Subsequently we changed our efforts from the fourth aim of our research project on mental distress to complete the studies on vitamin D and asthma control. A study on this has now been submitted to the American Journal of Epidemiology and we are awaiting feedback. Additionally, we have conducted a study on the association between insomnia symptoms and the development of asthma in adults. This has been one of our most novel and exciting studies to date. The manuscript has been accepted by the European Respiratory Journal and there will be a world-wide press release on its publication on the 2nd of February 2017. At the end of August 2016 the project came to an end due to administrative changes in the allocation of funding.
This scientific research has contributed to the knowledge of modifiable risk factor for asthma development and control. Our results may help create clinical guidelines and recommendations for the general population and patients with asthma in the future. Specifically, our research will provide much needed information on physical activity and vitamin D. Vitamin D supplement has been suggested to improve asthma control and our studies will help steer this debate.
Modifiable risk factors for asthma control in adults: the HUNT study
Asthma affects about 300 million people worldwide and represents approximately 1% of the total global disease burden. There is no cure for asthma, nor any effective means yet to prevent asthma. Therefore “asthma control” is the primary goal of asthma management.
While much research has focused on achieving asthma control with medication, fewer studies have focused on identifying potential modifiable risk factors such as general and abdominal obesity, vitamin D deficiency, physical activity, anxiety, and depression. Our project aims to investigate this knowledge gap in the medical literature. The first study investigating the association between serum 25-hydroxyvitamin D (25(OH)D) level and lung function changes in the general population was published in 2015. The study investigated the association both cross-sectional and prospectively in 1220 and 869 adults, respectively, from the HUNT Study in Nord-Trondelag. The study found that lower serum 25(OH)D levels were associated with greater lung function decline and impaired lung function in smokers. The second study which investigated the association between serum 25-hydroxyvitamin D (25(OH)D) level and lung function changes in adults with asthma was accepted in 2015. In this study we investigated 1329 adults with asthma and estimated the annual mean decline in lung function over a mean follow-up of 11.6 years. Results can be made available after the publication stage is complete. People with asthma should receive advice about physical activity. However, the benefits of physical activity on lung function, outside of cardiopulmonary fitness are unclear. We investigated the association between physical activity and lung function decline in adults with asthma from the HUNT. This study has been submitted and is under review. Results can be made available after the publication stage is complete. Additionally, we conducted a study on the relationship between multivitamin supplement and asthma and this study was published in 2015. We followed up 16,952 adults subjects who were free of asthma and had complete information on intake of multivitamin supplement in the HUNT Study from 1995-1997 to 2006-2008. We found that the intake of multivitamin supplements was associated with an increased risk of asthma. Furthermore in 2015 we welcomed a Master student to the project who is investigating potential sex differences in asthma control and secured funding for a PhD project on COPD in Norway. Finally, the overseas research stay at the Queensland Institute of Medical Research, Brisbane, Australia is currently being undertaken which includes work on genetic risk factors for asthma. One paper from this stay has been submitted and is currently under review. In summary, during this reporting period two papers have been published, one accepted and two are under-review. One Masters student has joined the project to investigate sex differences in asthma control, PhD funding has been secured for a future project on COPD and the overseas research stay is currently being completed.
Modifiable risk factors for asthma control in adults: the HUNT study – 2014 Report
The aim of the research is to look at the association between obesity, physical activity, vitamin D, anxiety, depression and asthma control. We will use the Health Study in Nord-Trondelag (HUNT) to examine these associations.
In Norway, the prevalence of adult asthma is about 8%. There is no cure for asthma, therefore treatment and prevention of exacerbations is important. Our project aims to investigate potential modifiable factors of asthma control. While much research has focused on asthma control through treatment with medications, far fewer studies have focused on how modifiable risk factors affect asthma control. Furthermore, the majority of the previous studies evaluating the associations between potential modifiable risk factors and asthma control have been cross-sectional. We have a unique opportunity to examine such factors by means of a prospective design. By advancing scientific research of modifiable risk factors of asthma control, guidelines for such factors may be included in asthma management and prevention plans, impacting on clinical practice and patient treatment. In connection with this project, the REK application was successfully submitted and approved. The application for the data was successfully submitted to the HUNT Research Center and data has since been received. The data has been checked and key variables have been defined and categorized. Lung function decline has been assessed to be one of the better objective measures of asthma control we have available. Two manuscripts have been drafted on the association between vitamin D and lung function (a major component of asthma control). The first investigating the association between vitamin D and lung function in the general population is under review with the European Respiratory Journal. The second investigating the same association in an asthma cohort is ready to be sent out to the co-authors for internal review and discussion. Results can be made available after the publication stage is complete.
Physical activity and incident asthma in adults: the HUNT Study, Norway.
BMJ Open 2016 Nov 18;6(11):e013856. Epub 2016 nov 18
Multivariate eQTL mapping uncovers functional variation on the X-chromosome associated with complex disease traits.
Hum Genet 2016 Jul;135(7):827-39. Epub 2016 mai 7
Vitamin D and Lung Function Decline in Adults With Asthma: The HUNT Study.
Am J Epidemiol 2016 Apr 15;183(8):739-46. Epub 2016 mar 18
Serum 25-hydroxyvitamin D level, smoking and lung function in adults: the HUNT Study.
Eur Respir J 2015 Aug;46(2):355-63. Epub 2015 mai 28
Intake of multivitamin supplements and incident asthma in Norwegian adults: the HUNT study
ERJ Open Research, 2015, http://dx.doi.org/10.1183/23120541.00036-2015