Background: Caregiving for an older spouse with cancer is a stressful event which impacts negatively on health. Recently, studies have focused on identifying physiological markers of stress. The pH in saliva, which has not been studied in the past in the context of stress of care, is a potential biomarker, since the pH level is likely to decrease in stressful situations due to activation of the sympathetic nervous system. Decrease in the pH level indicates an increase in saliva acidity.
Aims: To examine the effects of the stress of caregiving appraisal on depressive symptoms and level of pH in saliva among spouses of cancer patients, and examine the sense of mastery and coping strategies as possible mediators in the relation between the two..
Method: Cross-sectional data were collected in 2011by a structured interview from 68 convenience sampled cancer patients' spouses, and 42 age- matched individuals in the community. Linear regression analysis was used to examine the study objectives.
Results: The saliva pH level among cancer patients' spouses was lower than in the matched group. Lower levels of pH were predicted by higher stress appraisal and greater depression; and lower sense of mastery. Depression was predicted by higher stress appraisal and emotion-focused coping,and by lower sense of mastery and problem-focused coping.
Conclusions. The analysis showed that the level of pH in the saliva indicates more acidity in case of continuous stressful events such as caregiving of cancer patients, particularly among the spouses. However, more studies are still needed to show if the saliva pH level could be the potential marker of stress level.