A pilot study of office-based spirometry in patients with systemic lupus erythematosus.

BACKGROUND: Although pulmonary involvement is common in systemic lupus erythematosus (SLE), its effects on healthy lifestyle physical activity and its association with fatigue have not been well characterized. The goals of this study were to describe pulmonary function measured by office-based spirometry in patients with SLE and to compare spirometry with physical activity and systemic fatigue. METHODS: During an office visit, 49 patients with SLE completed spirometry assessing: a) forced expiratory volume in 1 s (FEV(1), a measure of airway patency and responsiveness); b) forced vital capacity (FVC, a measure of lung volume); and c) maximum voluntary ventilation (MVV, a measure of volume of air moved during rapid breathing) which has been hypothesized to be decreased in SLE due to muscle fatigue. Patients also performed a 2-min corridor walking test and completed self-reported questionnaires measuring weekly physical activity and systemic fatigue. RESULTS: Mean age was 45 years, 45 (92%) were women, mean SLEDAI and SLICC scores were 2.8 and 1.0, respectively. Some 24 patients had a smoking history, and 15 had a history of SLE-related pleuritis, which was not active at enrollment. FEV(1) and FVC were 96% of predicted, but MVV was only 55% of predicted. The distance walked during the corridor test was similar to that of patients with other chronic diseases; however, self-reported physical activity was less than recommended by national guidelines. There were no associations between spirometry values and history of pleuritis, other pulmonary diagnoses, or smoking (p > .10 for all comparisons), however, better FEV(1) (p = .04) and better FVC (p = .04) were associated with more self-reported activity and better FEV(1) (p = .03) was associated with longer distance walked during the corridor test. Most patients reported marked systemic fatigue; however, there were no associations between spirometry values and fatigue scores (p > .10 for all comparisons). CONCLUSIONS: MVV was markedly diminished, which supports the hypothesis that SLE may be associated with respiratory muscle fatigue during rapid breathing. MVV was not associated with mild-to-moderate patient-directed physical activity; however, lower FEV(1) and FVC were associated with less self-reported and performance-based physical activity.

Perceptions and measurements of physical activity in patients with systemic lupus erythematosus.

Promoting physical activity should be a priority for patients with systemic lupus erythematosus (SLE) because a sedentary lifestyle compounds patients' already disproportionately high risk for cardiovascular events and other adverse health outcomes. The objectives of this pilot study were to assess physical activity in 50 patients with SLE and to compare activity levels with clinical and psychosocial variables, such as fatigue, depressive symptoms, and social support and stress. Patients were asked open-ended questions about physical activity, and responses were coded according to Grounded Theory. Patients then completed the Paffenbarger Physical Activity and Exercise Index, a survey of lifestyle energy expenditure reported in kilocalories/week, performed a 2-minute walk test according to a standard protocol, and completed questionnaires measuring fatigue, depressive symptoms and social support and stress. Most patients (92%) were women, had a mean age of 45 years, and did not have extensive SLE. In response to open-ended questions, patients reported they avoided physical activity because they did not want to exacerbate SLE in the short term. However, if they could overcome initial hurdles, 46 patients (92%) thought physical activity ultimately would improve SLE symptoms. Walking was the preferred activity and 45 (90%) thought they could walk more. According to the Paffenbarger Index, mean energy expenditure was 1466 ± 1366 kilocalories/week and mean time spent in moderate-intensity activity was 132 ± 222 min/week. In total, 18 patients (36%) and 14 patients (28%) met physical activity goals for these values, respectively. Mean distance walked during the 2-minute test was 149 ± 28 m, equivalent to two blocks, which is similar to reports for stable patients with other chronic diseases. Patients with more social stress and more fatigue reported less physical activity. We conclude that the proportion of patients meeting physical activity goals was low; however, patients performed well on a standard walking test. Most patients believed physical activity provided long-term benefits for SLE and that they could be more physically active.