OBJECTIVES: To assess the benefits and harms of statins as an adjunct therapy for asthma in adults and children.
SEARCH METHODS: We searched for studies in the Cochrane Airways Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE Ovid SP and Embase Ovid SP, from their inception dates We handsearched the proceedings of major respiratory conferences. We also searched clinical trials registries for completed, ongoing and unpublished studies, and scanned the reference lists of included studies and relevant reviews to identify additional studies. The search is current to 7 February 2020.
SELECTION CRITERIA: We included randomised controlled trials (RCTs) with a parallel-group design that assessed statins for at least 12 weeks' duration. We considered all participants with a clinical diagnosis of asthma to be eligible, regardless of age, sex, disease severity and previous or current treatment. We planned to include studies reported as full text, those published as abstract only, and unpublished data.
DATA COLLECTION AND ANALYSIS: Two review authors independently screened and selected the studies, extracted outcome data and intervention characteristics from included studies, and assessed risk of bias according to standard Cochrane methodological procedures. We resolved any disagreement through discussion.
MAIN RESULTS: We found only one trial involving a total of 60 people living with asthma. The trial compared the effect of atorvastatin with a placebo (dummy treatment containing lactose) in treating people with chronic asthma. The trial did not report data for the primary outcomes or adverse events. There was uncertainty about the relative effect on forced expiratory volume in one second (FEV1) and peak expiratory flow (PEF) in the atorvastatin group compared with the placebo group. The study did not report serious adverse effects for the interventions. The included study had internal discrepancies in its reported data.
AUTHORS' CONCLUSIONS: The evidence was of very low certainty, so we are unable to draw conclusions about the effectiveness and safety of statins to treat asthma. High-quality RCTs are needed to assess the effect of statins on people with asthma. Well-designed multicentre trials with larger samples and longer duration of treatment are required, which assess outcomes such as adverse events, hospital utilisation and costs, to provide better quality evidence. Future studies that include subgroups of obese people with asthma are also required.
METHODS: A cross-sectional study was conducted in a steel factory in Terengganu, Malaysia to assess the metal dust exposure and its relationship to lung function values among 184 workers. Metal dust concentrations values (Co, Cr, and Ni) for each worker were collected using air personal sampling. Lung function values (FEV1, FVC, and %FEV1/FVC) were determined using spirometer.
RESULTS: Exposure to cobalt and chromium were 1-3 times higher than permissible exposure limit (PEL) while nickel was not exceeding the PEL. Cumulative of chromium was the predictor to all lung function values (FEV1, FVC, and %FEV1/FVC). Frequency of using mask was positively associated with FVC (Adj b = 0.263, P = 0.011) while past respiratory illnesses were negatively associated with %FEV1/FVC (Adj b = -1.452, P = 0.026). Only few workers (36.4%) were found to wear their masks all times during the working hours.
CONCLUSIONS: There was an exposure-response relationship of cumulative metal dust exposure with the deterioration of lung function values. Improvement of control measures as well as proper and efficient use or personal protection equipment while at work could help to protect the respiratory health of workers.