Stress and Long Qt Syndrome: the Role of Stress Proneness and Environmental Stress
Year: 2014
Type: dissertation
Study design: Observational Study
Abstract: Sudden deaths among seemingly healthy young individuals often have a cardiac origin. The long QT-syndrome (LQTS) is one of such potentially lethal cardiac conditions. LQTS is inherited and congenital, and it is typically characterized by a prolonged QT- interval in the electrocardiogram. The mutations that cause LQTS are known and they form several different LQTS subtypes. These mutations most commonly affect the potassium-channel encoding genes KCNQ1 and KCNH2 which define subtypes LQTS1 and LQTS2, and the sodium-effecting ion channel gene SCN5A which defines the subtype LQTS3. It is still unknown why some LQTS mutation carriers become symptomatic while others do not. Previous studies have attempted to uncover the causes behind LQTS symptoms by asking patients about specific events in their imminent environments during symptom onset ( what were you doing/what happened before you had the arrhythmia ). However, these studies typically have not employed rigorous psychometric questionnaires. In the current studies, data from 70-259 symptomatic and 103-328 asymptomatic LQTS mutation carriers, 203 relatives and 79-2056 people from the general Finnish population were utilised. The goal of the thesis was to study what causes symptoms in LQTS. More specifically, it was studied whether or not the symptomatic LQTS mutation carriers differ from asymptomatic ones in their stress proneness, as measured by two temperament scales: Cloninger's TCI and Gray's RST. In addition, to assess environmental stress, questionnaires measuring work stress based on the models by Karasek and Siegrist and their job control-demand and effort-reward scales were employed. Also two additional measures (scales) were employed to assess the interaction between environment and personality traits related to experiencing stress. First, Framingham s type A scale was employed to assess stressful work involvement i.e., individual tendency to experience one's working environment as stressful. Second, the Cope questionnaire and Stressful life events scale were employed to measure the level of emotional distress subjects experienced in response to a stressful life event in the past 12 months. The results indicated that all LQTS mutation carriers (symptomatic and asymptomatic) were equally stress prone, as measured by stress-related temperament sub-scales (harm avoidance and behavioural inhibition). However, the symptomatic patients experienced higher levels of work stress of both scales. In addition, the symptomatic patients experienced higher levels of both stressful work involvement and emotional distress in response to a stressful life event in the past 12 months. Subsequent research should combine the data on the environmental stressors which most likely lead to symptoms, whereby a putative risk score system could be established. Risk scores would enable identifying individuals who are at high risk. Subsequently, pertinent interventions and medical and other attention could be directed at these individuals.
Source: Työväentutkimus Vuosikirja
Author: Ilmari Määttänen
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W611514374