Reliability of the hand held dynamometer in measuring muscle strength in people with interstitial lung disease.

OBJECTIVE: To evaluate the inter-rater and intra-rater reliability of the hand held dynamometer in measuring muscle strength in people with interstitial lung disease (ILD). DESIGN: Test retest reliability of hand-held dynamometry for elbow flexor and knee extensor strength between two independent raters and two testing sessions. SETTING: Physiotherapy department within a tertiary hospital. PARTICIPANTS: Thirty participants with ILD of varying aetiology were included. Twenty participants completed the inter-rater reliability protocol (10 idiopathic pulmonary fibrosis, mean (SD) age 73 (10) years, 11 male) and 21 participants completed the intra-rater reliability protocol (10 idiopathic pulmonary fibrosis, mean age 71 (10) years, 11 male). MAIN OUTCOME MEASURES: Mean muscle strength (kg). Agreement between the two raters and testing sessions was analyzed using Bland-Altman plots and reliability was estimated using intraclass correlation coefficients (ICC). RESULTS: For elbow flexor strength there was a mean difference between raters of -0.6kg (limits of agreement (LOA) -5.6 to 4.4kg) and within raters of -0.3kg (LOA -2.8 to 2.3kg). The ICCs were 0.95 and 0.98, respectively. For knee extensor strength there was a mean difference between raters of -1.5kg (LOA -6.9 to 3.9kg) and within raters of -0.7kg (LOA -3.9 to 2.4kg). The ICCs were 0.95 and 0.97, respectively. CONCLUSIONS: Hand-held dynamometry is reliable in measuring elbow flexor and knee extensor strength in people with ILD.

Drugs potentially affecting the extent of airways reversibility on pulmonary function testing are frequently consumed despite guidelines.

BACKGROUND: The increase in forced expiratory volume in one second (FEV1) effected by a bronchodilator is routinely assessed when patients undertake pulmonary function testing (PFT). Several drug classes can theoretically affect the magnitude of the increase in FEV1. Withholding periods are advised for many but not all such drugs. Anecdotally, many subjects presenting for PFT are found to have taken drugs that might affect the test. We did an audit of patients presenting for PFT to assess the frequency with which FEV1 reversibility might be affected by drugs. METHODS: One hundred subjects presenting to the laboratory for PFT were questioned about recent drug consumption by an independent pharmacy intern. Reversibility of FEV1 was assumed to have been affected if drugs of interest were consumed within defined withholding periods or two half-lives for drugs without such data. RESULTS: Sixty-three subjects were prescribed drugs likely to affect FEV1 reversibility. Thirty-six subjects consumed at least one such drug within the withholding period. Half (18) of these patients consumed ß-blockers with or without ß-agonists. Sixty-five subjects did not recall receiving any advice about withholding drugs prior to the test and only 10 recalled receiving advice from their clinician or pulmonary function technician. CONCLUSION: Subjects presenting for PFT are infrequently advised to withhold drugs that may affect FEV1 reversibility, and consequently, often take such drugs close to the time of the test. Therefore, it is likely that the increase in FEV1 is frequently affected by interference from drugs and this might impact on diagnosis and/or treatment options.

The benefits of exercise training in interstitial lung disease: protocol for a multicentre randomised controlled trial.

BACKGROUND: Interstitial lung disease encompasses a diverse group of chronic lung conditions characterised by distressing dyspnoea, fatigue, reduced exercise tolerance and poor health-related quality of life. Exercise training is one of the few treatments to induce positive changes in exercise tolerance and symptoms, however there is marked variability in response. The aetiology and severity of interstitial lung disease may influence the response to treatment. The aims of this project are to establish the impact of exercise training across the range of disease severity and to identify whether there is an optimal time for patients with interstitial lung disease to receive exercise training. METHODS/DESIGN: One hundred and sixteen participants with interstitial lung disease recruited from three tertiary institutions will be randomised to either an exercise training group (supervised exercise training twice weekly for eight weeks) or a usual care group (weekly telephone support). The 6-minute walk distance, peripheral muscle strength, health-related quality of life, dyspnoea, anxiety and depression will be measured by a blinded assessor at baseline, immediately following the intervention and at six months following the intervention. The primary outcome will be change in 6-minute walk distance following the intervention, with planned subgroup analyses for participants with idiopathic pulmonary fibrosis, dust-related interstitial lung disease and connective-tissue related interstitial lung disease. The effects of disease severity on outcomes will be evaluated using important markers of disease severity and survival, such as forced vital capacity, carbon monoxide transfer factor and pulmonary hypertension. DISCUSSION: This trial will provide certainty regarding the role of exercise training in interstitial lung disease and will identify at what time point within the disease process this treatment is most effective. The results from this study will inform and optimise the clinical management of people with interstitial lung disease. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12611000416998.