Characteristics of the participants
Data from 3,338 eligible samples were analyzed in the present study. Table 1 shows the demographic characteristics of the respondents (1,154 males and 2,184 females). The average age was 39.23 ± 12.50 years, ranging from 15 to 97 years. The proportions of different education levels, including primary school or illiteracy, middle school, college or university, and postgraduate education, were 1.71%, 18.51%, 50.00%, and 29.78%, respectively. A majority of the participants were nonmanual workers (77.29%) with an income of 2000-10000 yuan per month (66.12%) and lived in cities (86.70%). Nearly one third of the participants reported that they previously had contact with someone with dementia. The demographic characteristics of sex-specific participants are presented in Supplementary Table 2. Age, type of job, and income were significantly different between male and female participants.
Awareness and understanding of risk factors for dementia
The proportions of each item identified by the respondents as a risk factor for dementia are presented in Fig. 1. Most of the participants could correctly recognize at least one risk factor, but 5.51% of them were unable to correctly recognize any single risk factor. The percentage of the participants who accurately identified the following risk factors for dementia was 84.24% for negative affect, 65.07% for alcohol use, 56.68% for smoking, 48.74% for hypertension, and 42.66% for diabetes.
Next the relationship between sociodemographic characteristics and knowledge of risk factors for dementia were assessed using multiple logistic regression analysis (Table 2). Compared with men, more women believed that negative affect (AOR = 1.68, 95% CI = 1.37-2.05) was a risk factor for dementia. The sex-specific analysis showed that female participants with different education levels and types of job as well as whether they had contact with dementia exhibited a distinct knowledge of risk factors for dementia; however, no demographic factors were associated with all five risk factors among male participants (Supplementary Table 3). Middle-aged individuals (aged 40-65 years) were significantly less likely to identify the contribution of negative affect (AOR = 0.69, 95% CI = 0.56-0.86), alcohol use (AOR = 0.83, 95% CI = 0.71-0.99), and smoking (AOR = 0.67, 95% CI = 0.57-0.79) to the progression of dementia compared with younger individuals (aged <40 years). Additionally, the group with a higher level of education (college, university, and postgraduate) had a better understanding of all five dementia risk factors for dementia compared with the group with a low education level (primary school or illiteracy) group.
Besides sex, age, and education level, the type of job, and contact with people with dementia also influenced the awareness of risk factors for dementia. Compared with nonmanual workers, manual workers had a poorer understanding of the relationship between smoking and dementia (AOR = 0.75, 95% CI = 0.59-0.96), and retired people had a lower understanding of all dementia risk factors for dementia. Respondents who were never in contact with patients with dementia were less likely to realize the roles that negative affect (AOR = 0.73, 95% CI = 0.59-0.91), alcohol use (AOR = 0.72, 95% CI = 0.61-0.86), smoking (AOR = 0.77, 95% CI = 0.66-0.91), and diabetes (AOR = 0.63, 95% CI = 0.54-0.74) played in the development and progression of dementia compared with those were in contact with patients with dementia. The awareness of risk factors for dementia was not influenced by income or type of residence.
Awareness and understanding of protective factors for dementia
Fig. 2 shows the proportions of participants who identified each item as a protective factor for dementia. The proportion of participants who chose none of the five items as protective factors was 4.79%. Most of the respondents correctly recognized exercise (90.00%), social activity (84.69%), intelligence games (80.92%), and reading (74.45%) as protective factors. However, only 6.14% of the individuals were aware that taking antihypertensive or hypolipidemic drugs was beneficial for delaying the onset of dementia.
Multiple logistic regression analysis was used to explore the effects of sociodemographic characteristics on the understanding of protective factors for dementia (Table 3). Sex, age, education level, type of job, and contact with patients with dementia had distinct influences on the awareness of protective factors for dementia. Compared with men, women knew more about the roles of exercise (AOR = 1.33, 95% CI = 1.04-1.72), social activity (AOR = 1.92, 95% CI = 1.57-2.35), intelligence games (AOR = 2.21, 95% CI = 1.82-2.69), and reading (AOR = 1.96, 95% CI = 1.65-2.33) in preventing dementia. Age, education level, type of job, and whether the individuals had contact with patients with dementia were associated with the knowledge of at least one protective factor for dementia in both male and female participants (Supplementary Table 4). Compared with younger individuals (aged < 40 years), middle-aged participants and elderly individuals were less aware that exercise (aged 40-65 years: AOR = 0.60, 95% CI = 0.45-0.79; aged ≥ 65 years: AOR = 0.41, 95% CI = 0.23-0.72), intelligence games (aged 40-65 years: AOR = 0.47, 95% CI = 0.38-0.58; aged ≥ 65 years: AOR = 0.43, 95% CI = 0.26-0.72), and reading (age 40-65 years: AOR = 0.79, 95% CI = 0.65-0.95; aged ≥ 65 years: AOR = 0.51, 95% CI = 0.31-0.83) were protective factors. People with a higher level of education had a better understanding of lifestyle variables that were protective factors for dementia, with the exception of antihypertensive and hypolipidemic drugs. Compared with nonmanual workers, manual workers had lower knowledge that exercise (AOR = 0.64, 95% CI = 0.45-0.92) and reading (AOR = 0.70, 95% CI = 0.53-0.91) were protective factors. Individuals who had contact with patients with dementia had a better understanding that social activity (AOR = 0.78, 95% CI = 0.62-0.98) and reading (AOR = 0.81, 95% CI = 0.67-0.98) were protective factors for dementia compared with individuals who had no contact with patients with dementia. Only people who had contact with patients who had dementia knew that antihypertensive and hypolipidemic drugs might help prevent dementia (AOR = 0.49, 95% CI = 0.35-0.67). The income and type of residence did not influence the awareness of protective factors for dementia as that of risk factors.