ACBRD PhD candidate Ralph Geerling discusses why he is interested in understanding more about the relationship between personality traits and type 2 diabetes self-care
The way a person rates his or her own health (subjective health) can be different from an assessment by a health professional or a medical test (objective health). Both subjective and objective health are often assessed in research to predict illness (morbidity) and death (mortality). However, inconsistencies between assessments are common, and these can create issues for making predictions about health outcomes. Contributing to this problem can be a person’s tendency to view their situation either more positively or negatively as a result of their personality.
Dr Roni Elran-Barak and her colleagues conducted a study to examine the role personality may play in modifying the relationship between subjective and objective health. They studied 368 older adults with type 2 diabetes, average age 72 years; 42% were women. They assessed personality using the OCEAN five-factor model which measures the traits: Openness to experience, Conscientiousness, Extraversion, Agreeableness and Neuroticism.
Subjective health was assessed with the question, “in general, compared to other people your age, would you say your health is (1) poor, (2) fair, (3) good, (4) very good, (5) excellent?” Objective health was assessed through a number of clinical markers, including: blood glucose and triglyceride levels, HbA1c, stress biomarkers, medication taking, blood pressure and body mass index; cognitive status was assessed using memory recall and attention tests, intelligence and language/semantic tests; and motor function status using handgrip strength and walking speed.
The researchers found that the relationship between objective and subjective health was moderated by neuroticism (the tendency to experience negative emotions). High neuroticism scores and low objective health scores (for hypertension, medications, lower cognitive test score, weaker handgrip and slower walking speed) predicted lower subjective health assessments.
The researchers suggest that these findings can be interpreted in two ways. Either 1) people who experience more negative emotions are more highly influenced by objective health results, leading to a negative subjective evaluation of their health; Or, 2) people who experience more negative emotions have a more accurate reflection of their subjective health because they are more in tune/sensitive to their objective health.
While higher ratings of subjective health are associated with lower mortality and better quality of life in chronic conditions such as diabetes (through reduced stress and increased optimism), they may inadvertently mask subjective indicators for treatment if they are at odds with objective health assessments. Whilst this study has demonstrated an intriguing relationship between high scores for the personality trait neuroticism and scores for subjective and objective health, the researchers note that we need longitudinal research (ie. collecting data over two or more periods of time) to clarify these interpretations.
Elran-Barak R, Weinstein G, Schnaider Beeri M and Ravona-Springer R. The associations between objective and subjective health among older adults with type 2 diabetes: The moderating role of personality. Journal of Psychosomatic Research, 2019; 117: 41-47.
