Dietary patterns and adult asthma: population-based case-control study

• Published in: Allergy (Copenhagen) Vol. 65; no. 5; pp. 606 - 615
• Main Authors: Bakolis, I, Hooper, R, Thompson, R.L, Shaheen, S.O
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford, UK : Blackwell Publishing Ltd 01.05.2010; Blackwell Publishing Ltd; Blackwell
• Subjects: Adolescent; Adult; Asthma; Asthma - epidemiology; Asthma - etiology; Biological and medical sciences; Bronchitis, Chronic - epidemiology; Bronchitis, Chronic - etiology; Case-Control Studies; Chronic obstructive pulmonary disease, asthma; Dermatology; Diet; Diet - adverse effects; dietary patterns; Dietary Supplements - adverse effects; Female; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Male; Medical sciences; Middle Aged; Pneumology; Principal Component Analysis; principal components analysis; Questionnaires; Sarcoidosis. Granulomatous diseases of unproved etiology. Connective tissue diseases. Elastic tissue diseases. Vasculitis; Surveys and Questionnaires; United Kingdom - epidemiology; Young Adult; London England; Human; Lung disease; Immunopathology; Nutrition; Respiratory disease; Dermatology; dietary patterns; Case control study; principal components analysis; Feeding; Asthma; Immunology; Diet; Bronchus disease; Adult; Obstructive pulmonary disease
• ISSN: 0105-4538; 1398-9995
• DOI: 10.1111/j.1398-9995.2009.02215.x

To cite this article: Bakolis I, Hooper R, Thompson RL, Shaheen SO. Dietary patterns and adult asthma: population-based case-control study. Allergy 2010; 65: 606-615. Epidemiological studies of diet and asthma have focused on relations with intakes of individual nutrients and foods and evidence has been conflicting. Few studies have examined associations with dietary patterns. We carried out a population-based case-control study of asthma in adults aged between 16 and 50 in South London, UK. Information about usual diet was obtained by food frequency questionnaire and we used principal components analysis to define five dietary patterns in controls. We used logistic and linear regression, controlling for confounders, to relate these patterns to asthma, asthma severity, rhinitis and chronic bronchitis in 599 cases and 854 controls. Overall, there was weak evidence that a 'vegetarian' dietary pattern was positively associated with asthma [adjusted odds ratio comparing top vs bottom quintile of pattern score 1.43 (95% CI: 0.93-2.20), P trend 0.075], and a 'traditional' pattern (meat and vegetables) was negatively associated [OR 0.68 (0.45-1.03), P trend 0.071]. These associations were stronger amongst nonsupplement users (P trend 0.030 and 0.001, respectively), and the association with the 'vegetarian' pattern was stronger amongst whites (P trend 0.008). No associations were observed with asthma severity. A 'prudent' dietary pattern (wholemeal bread, fish and vegetables) was positively associated with chronic bronchitis [OR 2.61 (1.13-6.05), P trend 0.025], especially amongst nonsupplement users (P trend 0.002). Overall there were no clear relations between dietary patterns and adult asthma; associations in nonsupplement users and whites require confirmation. The finding for chronic bronchitis was unexpected and also requires replication.