Because advances in care are increasing the life expectancy of patients with cystic fibrosis (CF), psychosocial aspects of the disease are garnering greater attention. One recent avenue of study has been the influence of personality traits on burden of disease in patients with CF. Most of these examinations, however, have focused not on the normative range of personality characteristics, but on psychopathologic conditions.
Raphael Hirtz, MD, PhD, and colleagues conducted a cross-sectional study to examine the relationship between normative personality characteristics and quantifiable healthcare outcomes, including predicted forced expiratory volume in one second (ppFEV1), BMI, and HRQOL, in patients with CF. The findings were published in BMC Pulmonary Medicine.
Using Personality Data to Tailor Support
“We hypothesize that, in line with adult patients with other chronic diseases, patients with CF show a higher prevalence of more extreme personality traits that affect their physical and psychological level of functioning,” Dr. Hirtz and colleagues wrote. “Beyond a comparison of patients with CF to the general population, the present study is also intended to identify certain personality clusters among patients with CF. Knowledge about personality traits in patients with CF could help to individualize and thereby increase the effectiveness of supportive interventions. This could result in improved HRQOL and health outcomes.”
The study included a total of 70 hospitalized patients with CF who completed the Cystic Fibrosis Questionnaire (CFQ-R 14+), which measures HRQOL, and a self-administered questionnaire about personality traits and disorders (PersönlichkeitsStilund Störungs-Inventar [PSSI]). Clinical data were collected, including ppFEV1, BMI, genotype, Pseudomonas aeruginosa colonization status, and the presence of CF-related diabetes mellitus. Further information on cough suppression therapy adherence and other demographic details were captured using a questionnaire developed by the research team.
The mean age of the study patients was 32.7 years (range, 18-71), and 41% of the group was female. The average BMI was 20.32. Moderate disease severity was based on lung function (average ppFEV1, 43.27).
Mean subscale scores and the prevalence of extreme personality traits on the PSSI were compared with the norming sample. A cluster analysis was conducted to identify personality styles among people with CF. The relationship between mean PSSI subscale scores and personality clusters with HRQOL and clinical outcomes was studied by regression analysis considering important confounders.
Identifying Personality “Clusters” in Patients With CF
The researchers identified two distinct personality “clusters” among patients with CF based on their scores on the PSSI. One cluster comprised patients with CF who had predominantly below-normal scores on five specific PSSI subscales: negativistic, schizoid, borderline, depressed, and paranoid. These subscales assess characteristics such as negativity, withdrawal from social interactions, emotional instability, low mood, and suspiciousness.
The second cluster comprised patients with CF who had high normal or elevated scores on these same PSSI subscales, indicating a higher level of these personality traits compared with the general population. The study found that these clusters did not differ significantly in terms of lung function, BMI, overall HRQOL, or therapy adherence.
However, the study found that patients in the cluster with below-normal scores on the specified subscales had a significantly higher HRQOL compared with those in the cluster with elevated scores.
Patients With CF Score Higher in “Rhapsodic” Personality
Of note, patients with CF compared with the general population showed higher scores on the “rhapsodic” personality trait, which reflects an exaggerated positive attitude toward life but difficulty in handling conflicts and problems. They also had lower scores on the “self-insecure” trait, which involves fear of negative evaluation by others and social insecurity.
Because HRQOL is largely influenced by personality, it is important to continue working toward identifying specific correlations between the two, Dr. Hirtz and colleagues suggest. “Since more recent personality theories assume that personality is modifiable, our findings imply that patients with accentuated personality traits may benefit from psychosocial support,” they concluded.