Theophylline for Irreversible Chronic Airflow Limitation: Results

Theophylline for Irreversible Chronic Airflow Limitation: ResultsComparsion of All n of 1 Trial Patients to All Standard Practice Patients (Primary Analysis)
Table 2 shows the CRQ scores, 6-min walk results, and spirometry values over time. No significant differences between the n of 1 trial patients and standard practice patients were seen in changes from baseline in these outcomes at 6 and 12 months. The 95% CLs for the between-group differences (n of 1 trial minus standard patients) in within-group changes over time (12 months minus baseline) in the CRQ Physical Function score, CRQ Emotional Function score, and 6-min walk were, respectively: -8.2, 2.5; -4.7, 5.7; and -26, 42 m).
Table 3 summarizes theophylline treatment over time. For n of 1 trial patients, theophylline status at 1 month was not recorded because the treatment decision was usually not made until at least the second month. No significant differences in theophylline use between the two groups were seen at any point over the year. Allergy treatment allergy treatment In seven patients (five n of 1 trial patients and two standard practice patients), theophylline was subsequently resumed by nonstudy physicians despite conclusions during the first 3 months of the study that it was not relieving dyspnea. These reversals were associated with slightly lower, but nonsignificant, patient confidence in the original decision (median confidence level among patients who switched, 3 [range, 2 to 5]; median confidence level among patients who did not switch, 2 [range, 1 to 6]; p > 0.2). Treatment reversals in the other direction (ie, subsequently stopping theophylline usage following a decision during the first 3 months that it was effective) did not occur. No significant differences in home oxygen use or cointerventions were seen between the n of 1 trial and standard practice patients in the week preceding the 6- and 12-month visits (data not shown).
Table 2—Mean (SD) Change from Baseline in CRQ, 6-Minute Walk, and Spirometry Values

No-Prior-Theophylline-UsePatients Prior-Theophylline-Use Patients All Patients
Standard Practic e n of 1 Trial Standard Practic e n of 1 Trial Standard Practi ce n of 1 Trial
CRQ total score
6 mo -3.0(12.1) 5.6 (17.7) 0.8(12.2) 0.4(14.5) -0.9(12.1) 2.9(16.0)*
12 mo -0.7(15.6) 6.3 (24.2) 1.7 (13.8) -7.4(16.9) 0.6 (14.4) -1.7(21.0)*
CRQ Physical Function score
6 mo -0.7 (6.6) 0(11.8) 0(6.1) 0.5 (7.3) -0.3 (6.2) 0.3 (9.5)*
12 mo -0.4 (8.5) -0.1 (15.5) 1.0 (7.2) -4.1 (9.5) 0.4 (7.7) -2.4(12.3)*
CRQ Emotional Function
score
6 mo -2.2 (6.7) 5.6 (8.1) 0.8 (7.1) -0.1 (8.1) -0.6 (7.0) 2.6 (8.5)*
12 mo -0.2 (7.7) 6.4(12.0) 0.7 (8.4) -3.3 (9.8) 0.3 (8.0) 0.8(11.6)*
6-min walk, m
6 mo 0(73) 2 (69) 13 (55) -16(62) 8(63) -7(65)*
12 mo -12 (84) 4(72) 9 (50) 8 (44) – 1 (68) 7 (56)*
FEVj, mL
6 mo 80 (190) 10(120) -30(140) -60(110) 20 (70) -30 (120)*
12 mo 0(170) -10(140) -40 (170) -60(110) -20 (70) -40 (130)*
FVC, mL
6 mo 310 (510) 140(380) -60 (460) -20 (260) 100 (510) 60 (330)*
12 mo 130 (370) 80 (500)span> -130 (420) -70 (410) -10(410) 0(450)*

Table 3—Proportion of Patients Using Theophylli

Time Period No-Prior-Theophylline-Use Patients Prior-Theophylline-Use Patients All Patients
Standard Practice n of 1 Trial Standard Practice n of 1 Trial Standard Practice n of 1 Trial
3 mo 2/14 (14%) 4/13 (31%) 11/17(65%) 7/18 (39%) 13/30 (43%) 11/31 (35%)
6 mo 4/13 (31%) 5/13 (38%) 11/17 (65%) 8/18 (44%) 15/30 (50%) 13/31 (42%)
12 mo 4/13 (31%) 5/13 (38%) 11/17 (65%) 11/18(61%) 15/30 (50%) 16/31 (52%)

Category: Airflow Limitation

Tags: irreversible chronic airflow limitations, n of 1 trials, randomized trial, theophylline