Subjective cognitive decline symptoms and its association with socio-demographic characteristics and common chronic diseases in the southern Chinese older adults

Subjective cognitive decline (SCD) may be the first symptomatic manifestation of Alzheimer's disease, but information on its health correlates is still sparse in Chinese older adults. This study aimed to estimate SCD symptoms and its association with socio-demographic characteristics, common chronic diseases among southern Chinese older adults.Participants aged 60 years and older from 7 communities and 2 nursing homes in Guangzhou were recruited and interviewed with standardized assessment tools. Pittsburgh Sleep Quality Index (PSQI), Patient Health Questionnaire-9 (PHQ-9) and Generalized Anxiety Disorder-7 (GAD-7) were used to measure poor sleep quality, depression symptoms and anxiety symptoms. The SCD symptoms were measured by SCD questionnaire 9 (SCD-Q9) which ranged from 0 to 9 points, with a higher score indicating increased severity of the SCD. Participants were divided into low score group (SCD-Q9 score ≤ 3) and higher score group (SCD-Q9 score > 3). Chi-square tests and multivariate logistic regression analysis were used for exploring the influences of different characteristics of socio-demographic and lifestyle factors on SCD symptoms. Univariate and multivariate logistic regression analysis were applied to explore the association between SCD symptoms with common chronic diseases.A total of 688 participants were included in our analysis with a mean age of 73.79 (SD = 8.28, range: 60-101), while 62.4% of the participants were females. The mean score of the SCD-Q9 was 3.81 ± 2.42 in the whole sample. A total of 286 participants (41.6%) were defined as the low score group (≤3 points), while 402 participants (58.4%) were the high score group (> 3 points). Multivariate logistic regression analysis revealed that female (OR = 1.99, 95%CI: 1.35-2.93), primary or lower education level (OR = 2.58, 95%CI: 1.38-4.83), nursing home (OR = 1.90, 95%CI: 1.18-3.05), napping habits (OR = 1.59, 95%CI: 1.06-2.40), urolithiasis (OR = 2.72, 95%CI: 1.15-6.40), gout (OR = 2.12, 95%CI: 1.14-3.93), poor sleep quality (OR = 1.93, 95%CI: 1.38-2.71), depression symptoms (OR = 3.01, 95%CI: 1.70-5.34) and anxiety symptoms (OR = 3.11, 95%CI: 1.29-7.46) were independent positive related to high SCD-Q9 score. On the other hand, tea-drinking habits (OR = 0.64, 95%CI: 0.45-0.92), current smoking (OR = 0.46, 95%CI: 0.24-0.90) were independent negative related to high SCD-Q9 score.Worse SCD symptoms were closely related to common chronic diseases and socio-demographic characteristics. Disease managers should pay more attention to those factors to early intervention and management for SCD symptoms among southern Chinese older adults.