Rehabilitation of Idiopathic Pulmonary Fibrosis (IPF) Patients
Condition: Idiopathic Pulmonary Fibrosis
MeSH terms: Pulmonary Fibrosis; Idiopathic Pulmonary Fibrosis; Fibrosis
Study type: Interventional

Summary: 
      The incidence and prevalence of IPF increase exponentially with age, and IPF occurs more
      often in older males. Cigarette smoking and environmental dust exposures are known risk
      factors for developing IPF. For example, the recently deployed military population, as it
      ages, is at especially increased risk of IPF. No effective therapies exist, although lung
      transplantation is used to extend survival of selected patients.

      Defining specific therapy to improve exercise tolerance and dyspnea in IPF patients is thus
      an urgent priority of veteran-oriented research programs.
    

Detailed description: 
      Chronic lung disease is common in the veteran population. While chronic obstructive pulmonary
      disease (COPD) is most prominent, fibrotic lung diseases, typified by idiopathic pulmonary
      fibrosis (IPF), are clearly increasing. We have developed extensive experience with a VA
      idiopathic pulmonary fibrosis (IPF) population in the context of a randomized, controlled
      clinical trial of vasodilator therapy.

      Based on the current literature and our preliminary experience with exercise testing in IPF
      patients, we hypothesize that:

        1. Formal pulmonary rehabilitation (i.e., an aerobic exercise program) will result in
           improved outcomes for IPF patients, demonstrable as an:

             1. Increase in exercise tolerance as quantified by 6-minute walk test (MWT) distance;

             2. Decrease in post-exercise dyspnea as quantified by the Borg dyspnea scale; and an

             3. Overall subjective improvement in quality of life as quantified by Saint George's
                Respiratory Questionnaire.

        2. Metabolic and physiologic mechanisms of improved exercise tolerance and decreased
           dyspnea will include:

             1. More efficient oxygen metabolism demonstrated by maximum O2 uptake (VO2max);

             2. Decreased post-exercise oxidant stress demonstrated by post-exercise isoprostanes
                and plasma total antioxidant capacity (TAC); and,

             3. Maintenance of maximum inspiratory and expiratory pressures (PInmax and PExmax).

      Our Specific Objectives are:

        1. To investigate formal pulmonary rehabilitation and exercise tolerance in IPF patients

           The following important endpoints will be assessed to test the working hypothesis that
           pulmonary rehabilitation improves exercise capacity and lessens dyspnea:

             1. 6-MWT distance;

             2. Dyspnea index; and,

             3. Quality of life (Saint George's Respiratory Questionnaire [SGRQ] and International
                Physical Activity Questionnaire [IPAQ]).

        2. To assess changes in oxygen uptake, markers of oxidant stress and pulmonary function
           resulting from pulmonary rehabilitation

      To test the working hypothesis that improved outcomes are associated with more efficient O2
      utilization, decreased markers of oxidant stress and maintained effort dependent pulmonary
      function, the following variables will be measured:

        1. Peak oxygen uptake (VO2peak) during constant load exercise;

        2. Markers of oxidant stress, including plasma and urine isoprostanes; and,

        3. Maximum inspiratory and expiratory pressures (PInmax and PExmax). Completion of these
           Specific Objectives will position our research group to conduct future studies of 1)
           mechanisms of exercise limitation and 2) antioxidant therapies, both in this defined
           population and those who are at risk of developing pulmonary fibrosis. The long term
           impact of this application is thus to develop effective pulmonary rehabilitation
           strategies for IPF patients, based on knowledge of underlying changes in oxygen
           metabolism and oxidant stress.
    

Intervention name(s): pulmonary rehabilitation
Intervention type(s): Behavioral
Intervention description(s): structured exercise program
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: oxidant stress; exercise