Immediate and long term effects of weight reduction in obese people with asthma: randomised controlled studyBMJ 2000; 320 doi: https://doi.org/10.1136/bmj.320.7238.827 (Published 25 March 2000) Cite this as: BMJ 2000;320:827
- Brita Stenius-Aarniala, professor of pulmonary medicinea (, )
- Tuija Poussa, statistics consultantb,
- Johanna Kvarnström, medical studenta,
- Eeva-Liisa Grönlund, consultant in pulmonary medicinec,
- Mikko Ylikahri, licentiate in medicinea,
- Pertti Mustajoki, consultant in pulmonary medicinec
- a Division of Pulmonary Medicine and Allergology, Helsinki University Central Hospital, FIN-00029 HYKS, Helsinki, Finland
- b STAT-Consulting, Takojankatu 15 B, FIN-33540 Tampere, Finland
- c Peijas Hospital, Sairaalakatu 1, FIN-01400 Vantaa, Finland
- Correspondence to: B Stenius-Aarniala, Department of Medicine, PL 340 Helsinki, University Central Hospital, FIN-00029 HYKS, Finland
- Accepted 11 January 2000
Objective: To investigate the influence of weight reduction on obese patients with asthma.
Design: Open study, two randomised parallel groups.
Setting: Private outpatients centre, Helsinki, Finland.
Participants: Two groups of 19 obese patients with asthma (body mass index (kg/m2) 30 to 42) recruited through newspaper advertisements.
Intervention: Supervised weight reduction programme including 8 week very low energy diet.
Main outcome measures: Body weight, morning peak expiratory flow (PEF), forced vital capacity (FVC), forced expiratory volume in one second (FEV1); and also asthma symptoms, number of acute episodes, courses of oral steroids, health status (quality of life).
Results: At the end of the weight reducing programme, the participants in the treatment group had lost a mean of 14.5% of their pretreatment weight, the controls 0.3%. The corresponding figures after one year were 11.3% and a weight gain of 2.2%. After the 8 week dieting period the difference in changes in percentage of predicted FEV1 from baseline in the treatment and control groups was 7.2% (95% confidence interval 1.9% to 12.5%, P=0.009). The corresponding difference in the changes in FVC was 8.6% (4.8% to 12.5%, P<0.0001). After one year the differences in the changes in the two groups were still significant: 7.6% for FEV1 (1.5% to 13.8%, P=0.02) and 7.6% for FVC (3.5% to 11.8%, P=0.001). By the end of the weight reduction programme, reduction in dyspnoea was 13 mm (on a visual analogue scale 0 mm to 100 mm) in the treatment group and 1 mm in the control group (P=0.02). The reduction of rescue medication was 1.2 and 0.1 doses respectively (P=0.03). After one year the differences in the changes between the two groups were −12 for symptom scores (range −1 to −22, P=0.04) and −10 for total scores (−18 to −1, P=0.02). The median number of exacerbations in the treatment group was 1 (0–4) and in the controls 4 (0–7), P=0.001.
Conclusion: Weight reduction in obese patients with asthma improves lung function, symptoms, morbidity, and health status.
Funding The Finnish Culture Foundation, the Association of the Pulmonary Disabled, and the Wilhelm and Else Stockmann Foundation. Nycomed Pharma supplied the dietary preparation (Nutrilett) free of charge.
Competing interests None declared.
website extra A chart showing the flow of participants and a table showing baseline characteristics are available on the BMJ's website www.bmj.com
- Accepted 11 January 2000