Patients' attitude to subcutaneous immunoglobulin substitution as home therapy

Since 2003, immunoglobulin preparations have been approved for subcutaneous (s.c.) use in Germany. Although all our adult patients on intravenous (i.v.) substitution were offered to switch to s.c. home therapy, approximately half of them refused to change.

To evaluate patients' attitude towards s.c. home therapy, a questionnaire was developed and sent to 125 patients. Questions had to be answered by ticking numbers on a Likert scale from 1 (not at all) to 8 (very much). Four scales of the Freiburg Personality Inventory (FPI) were added. From the 70 questionnaires returned (56%), 61 could be analysed (i.v. n = 28, s.c. n = 33).

The i.v. treated patients were afraid of being more busy with self-administration (6.9 +/- 2.1). This was not a serious concern in the s.c. treated group (3.6 +/- 1.8, p < 0.001). Many i.v. treated patients worried about severe adverse reactions at home (4.7 +/- 2.8), but patients in the s.c. group did not (1.7 +/- 1.0, p < 0.001). The statement "I dislike to puncture myself" reached 5.3 +/- 2.7 points in the i.v. treated group, but only 2.0 +/- 1.1 (p < 0.001) in the s.c. treated patients. As main reason, patients on i.v. substitution considered s.c. therapy as inconvenient (48%). Secondly, they were afraid of side effects (31%). All patients on s.c. therapy appreciated the new treatment (7.2 +/- 1.0). Main advantage for them was an increase of flexibility (6.6 +/- 1.6). The FPI displayed lower values for s.c. treated patients in the scales "Physical Complaints" and "Emotional Lability".

Those patients who had changed to s.c. therapy were highly satisfied. However, others preferred to stay on i.v. treatment for different reasons. Perception of inconvenience, anxiety of side effects, but also personal traits may play a role.