Characteristics of the subjects
In the present study, data from 3,338 eligible samples were analyzed. 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. 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 subjects were white-collar workers (77.29%) with 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.
Awareness and understanding of dementia risk factors
The proportions of each item that was identified by the respondents as a risk factor for dementia are presented in Fig. 1. Most of the participants were able to correctly recognize at least one risk factor, but 5.51% of them were unable to correctly recognize any single risk factor. The percentages of the participants who accurately identified the following risk factors for dementia were 84.24% for negative affect, 65.07% for alcohol use, 56.68% for smoking, 48.74% for hypertension, and 42.66% for diabetes.
We next assessed the relationship between sociodemographic characteristics and knowledge of dementia risk factors using multiple logistic regression analysis (Table 2). Compared with men, more women believed negative affect (OR = 1.68, 95% CI = 1.37-2.05) was a risk factor for dementia. The age-specific analysis found that middle-aged individuals (40-65 years old) were significantly less likely to identify the contribution of negative affect (OR = 0.69, 95% CI = 0.56-0.86), alcohol use (OR = 0.83, 95% CI = 0.71-0.99), and smoking (OR = 0.67, 95% CI = 0.57-0.79) to the progression of dementia compared with younger individuals (< 40 years old), indicating that the older age group might have lower levels of knowledge of dementia risk factors. Additionally, the group with a higher level of education (college, university, and postgraduate education) had a better understanding of all five dementia risk factors.
In addition to gender, age, and education level, the type of job and contact with people with dementia also influenced the awareness of dementia risk factors. Blue-collar workers had a poorer understanding of the relationship between smoking and dementia (OR = 0.75, 95% CI = 0.59-0.96) compared with white-collar workers, and retired people had an insufficient understanding of all dementia risk factors. Respondents who were never in contact with individuals with dementia were less likely to realize the roles that negative affect (OR = 0.73, 95% CI = 0.59-0.91), alcohol use (OR = 0.72, 95% CI = 0.61-0.86), smoking (OR = 0.77, 95% CI = 0.66-0.91), and diabetes (OR = 0.63, 95% CI = 0.54-0.74) play in the development and progression of dementia. The awareness of risk factors for dementia was not influenced by income or type of residence.
Awareness and understanding of dementia protective factors
Fig. 2 shows the proportions that 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 of dementia (Table 3). Gender, age, education level, type of job, and contact with individuals with dementia had distinct influences on the awareness of protective factors for dementia. Income and type of residence did not influence the awareness of protective factors for dementia.
Compared with men, women knew more about the roles of exercise (OR = 1.33, 95% CI = 1.04-1.72), social activity (OR = 1.92, 95% CI = 1.57-2.35), intelligence games (OR = 2.21, 95% CI = 1.82-2.69), and reading (OR = 1.96, 95% CI = 1.65-2.33) in preventing dementia. Compared with younger individuals (< 40 years old), middle-aged subjects and elderly individuals were less aware that exercise (40-65 years old: OR = 0.60, 95% CI = 0.45-0.79; ≥ 65 years old: OR = 0.41, 95% CI = 0.23-0.72), intelligence games (40-65 years old: OR = 0.47, 95% CI = 0.38-0.58; ≥ 65 years old: OR = 0.43, 95% CI = 0.26-0.72), and reading (40-65 years old: OR = 0.79, 95% CI = 0.65-0.95; ≥ 65 years old, OR = 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 white-collar workers, blue-collar workers had lower knowledge that exercise (OR = 0.64, 95% CI = 0.45-0.92) and reading (OR = 0.70, 95% CI = 0.53-0.91) were protective factors. Individuals who had contact with individuals with dementia had a better understanding that social activity and reading were protective factors for dementia. Only people who had contact with someone who lived with dementia knew that antihypertensive and hypolipidemic drugs might help prevent dementia.