Effect of Positive Mental Health on Elderly Patients with Chronic Diseases: The Chain-Mediated Effects of Gratitude and Forgiveness Tendencies at a Tertiary Hospital in Guangzhou

<b>Background:</b> This study aims to elucidate the mediating roles of gratitude and forgiveness tendency between mature happiness and positive mental health, seeking to reveal the significance of enhancing these psychological traits to enhance the well-being of this population, so as to provide a theoretical foundation for strategies aimed at promoting healthy aging and enhancing the happiness of elderly patients with chronic illness. <b>Methods:</b> From April to October 2024, elderly patients with chronic diseases in the geriatric department of a tertiary hospital in Guangzhou China were selected as subjects through convenience sampling. The study utilized the general information questionnaire, the Chinese Version of Mature Happiness Scale-Revised, the Positive Mental Health Scale, the Gratitude Questionnaire-6, and the Tendency to Forgive Scale for data collection. <b>Results:</b> A total of 319 valid questionnaires were obtained. The mature happiness, positive mental health, gratitude, and forgiveness tendency of elderly patients with chronic diseases were at a medium level. Correlation analysis indicated that mature happiness was positively associated with positive mental health, gratitude, and forgiveness tendency. Mediation analysis illuminated that positive mental health robustly predicted the extent of gratitude, which served as a pivotal predictor of mature happiness. Moreover, gratitude and forgiveness tendency together played a significant chain mediating role between mature happiness and positive mental health, accounting for 26.31% of the total effect (<i>p</i> = 0.246). <b>Conclusions:</b> Positive mental health has a significant positive impact on mature happiness amongst elderly patients with chronic diseases, mediated through the chain mediating effects of gratitude and forgiveness tendency. Consequently, fostering traits of gratitude and forgiveness in this population may enhance their mental health and mature happiness.