Epidemiologic Study On Depression Among Rural Residents In Liuyang

BACKGROUDDepression is one of the most common mental disorders in China. The prevalence of depression reported around the world had considerable differences between different countries or regions. The reported lifetime prevalence of depression arranged from 5.2% to 16.2% in the west countries, but varied from 1.15% to 8.6% in China according to several national and regional epidemiologic studies about mental disorders in recent years. These differences were due to the different samples, methods of case determination, diagnostic criteria and instruments and so on. In China, there were lots of special epidemiologic studies about depression in the patients of primary health care or outpatient services in general hospitals, and their results all showed a comparatively high prevalence of depression in this population. However, there was no special epidemiologic study on depression in community population, especially in rural community population in China. It is still unclear about the symptoms characteristics and the related factors to the depression, as well as the status of their health care utilization among community patients. Furthermore, the existing epidemiologic studies had many methodological problems on the methods of field survey, screening instruments and diagnostic criteria. This study explored the prevalence of depression and risk factors in rural residents of our country, as well as the characteristics of symptoms and health services utilization of rural community patients with depression. It was also a preliminary study on the feasibility of methods and instruments in epidemiologic surveys of depression in rural community population in China. In addition, this paper could provide evidences to further epidemiologic study and strategy development of depression prevention and control.OBJECTIVETo assess the prevalence of depression and its related factors in rural residents, as well as the positive rates of symptoms and the status of health care utilization among rural patients with depression in China; to study on the methods and instruments suitable for epidemiologic surveys of depression in Chinese rural community, and to provide evidences to further epidemiologic study and strategy development of depression prevention and control.METHODSThe subjects of this study were rural usual residents who were≥15 years old in Liuyang city. Stratified multistage random sampling was conducted to stratify all the Xiangs/Towns into three strata according to the level of economic development, and one Xiang/Town from each stratum was selected randomly. At the first stage, a baseline investigation was conducted in the three Xiang/Towns, then,7857 families were randomly selected, which included 28316 registered persons who were≥15 years old. A total of 17713 individuals were then excluded because of living in their hometown for less than 6 months in the last year before investigation. Finally, a sample of 10603 persons who were≥15 years old was investigated. Face-to-face interviews were conducted for depression screening from March to May in 2007. The Structured Clinical Interview (SCID) was used to assess major depressive episode (MDE) and dysthymic disorder according to Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) criteria.The patients with depression who met the DSM-IV criteria were screened out as a sample to assess the positive rates of symptoms and status of the health care utilization. All the subjects were interviewed by trained investigators to examine the 9 symptoms of MDE by SCID, and to collect socio-demographic variables and other correlates by self-designed questionnaires "A General Condition Questionnaire" and "Questionnaire on behavior of help seeking of patients with mental disorders".RESULTSⅠ. The Prevalence of Depression and its Related FactorsA total of 7347 individuals were interviewed in which there were 3358 males and 3989 females. The response rate was 69.3%. The mean age was 49.73-16.30 years and there was a significant age difference between different gender groups (t=3.059, P=0.002). Among 7347 subjects,295 patients with depression were screened out and diagnosed. One hundred and forty cases were suffering from current MDE, and the point prevalence was 1.9%(95%CI:1.6%-2.2%). Ninety four cases had past MDE(1.3%,1.0%-1.6%) and 61 cases had dysthymic disorder(0.8%,0.6%-1.0%). The total prevalence of depression was 4.0%(3.6%-4.4%).The prevalence of depression was higher in females (4.6%) than in males (3.2%). The male to female sex ratio was 0.706, and the difference had statistical significance (χ2=8.928, P=0.030). The mean age of the patients was 52.3-13.0 years old, and the prevalences in 45 to 75 years old group was significantly higher than other age groups (χ2=42.458, P=0.000). After stratified by gender, the prevalence difference still reached statistical significance among age groups (P<0.01). Furthermore, after standardized by the age proportion of 28316 registered residents who were≥15 years old, the age-adjusted prevalence was 2.78%(95%CI: 2.22%- 3.34%) in males and 3.82%(95% CI:3.23%- 4.41%) in females, and the difference was also statistically significant (χ2=6.129, P=0.013); the age-adjusted prevalence in the whole population was 3.35%(95%CI:2.94%-3.76%).The prevalence of depression in various education level groups from highest to lowest was 4.6% in none and primary,3.0% in junior high school, and 2.8% in senior high school and higher education group. The prevalence of depression was higher in the lower education level (χ2=12.424, P=0.002). The prevalence in marital status groups were 10.6% in divorced,8.2% in deuterogamy,6.2% in widowed,3.9% in first married to 1.8% in unmarried group. There was a statistical significance with the difference (χ2=26.677, P=0.000). The prevalence in agricultural workers (4.7%) is higher than industrial and commercial workers (2.8%) and other occupation group (2.0%), and the difference was statistically significant (χ2=17.410, P=0.008). The prevalence of depression and income levels had a negative correlation, the prevalences and RR increased while the annual income per capita of the family decreased (χ2=14.972, P=0.039), and the Spearman rank correlation index (rs) was-0.905 (P=0.002). The prevalence of depression had a trend of increasing with the decreasing of the number of family members (rs=-0.857, P=0.007) or the number of usual resident family members (rs=-0.964, P=0.000), and the differences were both statistically significant (P<0.05). The prevalence of persons living alone (7.2%) was higher than persons living with others (3.9%), and the difference was statistically significant (χ2=4.085, P=0.043). Additionally, patients with confirmed chronic physical diseases had a higher comorbidity of depression than patients without chronic physical diseases (7.6% and 2.4% respectively), and the difference was statistically significant (χ2=110.402, P=0.000).The results of multiple logistic regression analysis showed the influential factors of depression were female (OR=1.334,95%CI:1.040-1.711), age (OR=1.012,1.002-1.022), primary or lower education level (OR=1.428,1.048 - 1.946), agricultural workers (OR=1.490,1.050-2.115), unstable marital status (OR=1.628,1.174-2.260), lower income (OR=1.361,1.066-1.737), number of family usual resident members (OR=1.132,1.042 - 1.230) and suffering from any chronic physical disease (OR=3.020,2.345-3.888).Ⅱ. The Positive Rates of Symptoms of Depression and Related Factors There were 234 cases diagnosed as MDE,86 males and 148 females. The range of age was from 15.3 to 85.9 years old, and the mean age was 52.3±13.2 years old. The difference of age proportion between male and female did not reach statistical significance (χ2=6.597, P=0.252).The positive rates of the 9 symptoms of MDE from highest to lowest were depressed mood (96.6%), diminished interest or pleasure in all (85.0%), fatigue or loss of energy (84.6%), insomnia or hypersomnia (83.3%), appetite or weight change (68.4%), diminished ability to think or concentrate, or indecisiveness (64.5%), feelings of worthlessness or excessive or inappropriate guilt (62.4%), recurrent suicidal ideation or attempt (37.2%) and psychomotor agitation or retardation(27.4%). There were 7.7% of the patients were positive on all of the 9 symptoms. The positive rate of appetite or weight change in males (76.7%) was higher than females (63.5%), and the difference had significance statistically (χ2=4.403, P=0.036). The positive rates of suicidal ideation or attempt in females (40.2%) was higher than males (30.2%), and the difference had significance statistically (χ2=7.551, P=0.023). However, no statistical significance was found among the positive rates of other symptoms across age and gender (P>0.05).Among the somatic depressive symptoms, the most frequent is fatigue or loss of energy, followed by insomnia or hypersomnia and appetite or weight change. The positive rates of sleep change had a tendency of increasing while age goes up (χ2=11.272, P=0.046), and majority were insomnia. The mean sleeping time reported by patients was 4.53 hours a day. The differences of other somatic symptoms among gender or age groups did not reach statistical significance (P>0.05). Compared with the results of a domestic study on clinical patients with MDE, the positive rates of the somatic symptoms of rural community patients in this study were all lower, and the differences of decrease in appetite and weight loss had statistical significance (P＜0.001), while the differences of fatigue or weak and sleep disorders had no statistical significance (P>0.05).Among the 234 MDE patients,147 cases (62.8%) had suicidal ideas at any time, and 49 cases (20.9%) had recurrent suicidal ideation but no plan or attempt. Twenty one cases (9.0%) had suicidal plan but no attempt, and 17 cases (7.3%) had suicidal attempt at least once. The positive rates of suicidal ideation or attempt in females (41.2%) was higher than males (30.2%), the difference was statistically significant (χ2=10.020, P=0.040). It was also higher in deuterogamy, divorced and widowed group (50.0%) than never married or first married group (34.0%), and the difference was statistically significant (Mann-Whitney Test Z=2.577, P=0.010). The results of multiple logistic regression analysis showed that the patients in unmarried or first married marital status presented less suicidal ideation or attempt than who were in euterogamy, divorced and widowed marital status (β=-0.661, P=0.047, OR=0.516, OR 95% CI:0.269-0.991). However, the gender, age, education level, occupation, type of family, income, confirmed physical disease and family history of mental disorders had no significant relationship with suicidal ideation or attempt (P>0.05).The number of positive symptoms of patients with MDE correlated positively to recurrent suicidal ideation or attempt (χ2=36.304, P=0.000). The results of multiple logistic regression analysis revealed that other symptoms of MDE were correlated to suicidal ideation or attempt. The "diminished interest or pleasure in all" correlated negatively to suicidal ideation or attempt (OR=0.378,95%CI:0.178-0.801), but "feelings of worthlessness or excessive or inappropriate guilt" correlated positively to suicidal ideation or attempt (OR=2.084,1.158-3.750).Ⅲ. Health Care Utilization of Rural Patients with DepressionThe mean age of 295 patients with depression,110 males and 185 females, was 52.3-13.0 years old. The difference of age proportion between males and females had no statistical significance (χ2=8.426, P=0.134).The initial measures took by patients with depression after the onset of depressive symptoms were "rest caring"(69.5%), "to pray and worship buddha or to seek folk shaman treatments" (9.2%), "to treat by oneself (8.8%), and "to seek help from medical institutions" (6.1%). The factors influenced the initial measures statistically significantly were gender, attribution of the symptoms, and suffering from chronic physical diseases.Forty five cases (13.5%) have sought helps from xiang/town health centers or other higher level formal medical institutions. The rate of seeking help from formal medical institutions in females (18.9%) was higher than in males (9.1%), and the difference had statistical significance (χ2=5.541, P=0.023). The education level of patients or decision maker of the family and the highest education level in the family members had effects on seeking help from formal medical institutions. It was higher in group of junior high school and higher than in group of primary and lower, and the differences were all statistically significant (P<0.05). The rate in patients coming from expanded family (23.0%) was higher than patients from traditional core family (11.4%) or other kinds of family (9.1%), and the difference was statistically significant (χ2=7.064, P=0.029). Besides, the rate of help seeking increased along with increasing income levels (χ2=8.287, P=0.016). The results of multiple logistic regression analysis showed that the related factors on the rate of help-seeking were male (OR=0.363,95%CI:0.164 - 0.805), age (OR=1.040,1.012-1.069), an agricultural worker as the decision maker of the family(OR=0.352,0.176 - 0.707), the kind of family as an expanded one (OR=2.593,1.292 - 5.204), and family history of any mental disorder (OR=3.642,1.084-12.235). The symptoms of patients with MDE also had effect on the rate of help-seeking. The rates of help seeking in the patients who were positive on "diminished interest or pleasure in all" and "appetite or weight change" (11.6% and 10.6% respectively) were lower than that in patients who were negative (31.4% and 23.0% respectively). The rate of help seeking in the patients with suicidal ideation or attempt (24.1%) was higher than that in patients without the symptom (8.8%). All the differences above were statistically significant (P<0.05).The rate of help-seeking delay (delay-time>30 days) of depression patients was 95.0%, and 70.2%(207/279) of the patients had a delay over 1 year. The medium of delay-time was 1211 days. The results of multiple logistic regression analysis showed that the related factors on help-seeking delay were age (OR=0.956,0.916-0.998), an agricultural worker as the decision maker of the family (OR=3.360,1.049-10.761), and coming from an expanded family (OR=0.208,0.061-0.705). The leading factors to help-seeking delay by the patients'reports were "to hold off for feeling it's not a big trouble" (34.1%), "to hold off for economic difficulties" (26.8%), and "having no knowledge of being sick" (17.1%).Among 45 patients who have sought help from medical institutions, 95.6% went to general hospitals and only 2 cases (4.4%) went to psychiatric hospitals at the first time.66.7% of the patients sought help from xiang/town health centers, and 95.6% sought help from hospitals of county level or lower. Only 1.7%(5/295) of the patients had been to mental health professional institutions, and all of them were diagnosed with MDE. Patients with an education of junior high school or higher and family history of any mental disorder had a higher rate of help-seeking to professional institutions, and the differences were statistically significant (P＜0.05). Only 6 patients (2.0%) have been diagnosed as "depression" or "neurosis", others have never been distinguished or diagnosed.Among the 40 patients (13.6%) had been treated (include Chinese traditional medicine treatments),10 cases (3.4%) of MDE had been hospitalized, and merely 3 cases (1.0%) of past MDE had been treated by psychiatric drugs. The treatment rate was higher in females (18.9%) than in males (4.5%), and the difference was statistically significant (χ2=12.159,P=0.000). The results of multiple logistic regression analysis showed that the related factors on treatment rate were gender (OR=0.175, 0.063-0.491), age (OR=1.050,1.016-1.084), suffering from chronic somatic disease (OR=3.O38,1.287-7.171), an agricultural worker as the decision maker of the family(OR=0.303,0.143-0.642), and coming from an expanded family (OR=2.837,1.335-6.028). The main reasons of non-treatment reported by patients were "the treatment would be unnecessary for feeling the illness not so severe" (32.6%), "economy difficulty" (32.2%), "thinking it is un-curable" (7.9%).There were 21.3% of the patients had sought help from voodoo doctors or simplers. The rate of superstitional help seeking was higher in females (26.3%) than in males (13.1%), and the difference was statistically significant (χ2=6.909, P=0.009). There were 44.8% of the patients and 38.8% of the patients'family members have been to pray and worship buddha. Other factors affected on superstitional help-seeking behaviors was age and the attitude towards Ghosts and Gods, and they all had statistical significance (P＜0.05).CONCLUSIONS1. The prevalence of depression in rural residents in Liuyang was 4.0%(95%CI:3.6%-4.4%). It was higher in females than males, and higher in 45-75 years old age group than in other age groups.2. The related factors of depression included lower education level, agricultural worker, unstable marital status (unmarried until 30 years old, deuterogamy, divorced or widowed), lower income and suffering from any chronic physical disease.3. There was no distinct difference between symptoms of rural community patients with MDE and clinical patients, but the positive rates of some symptoms (such as appetite or weight change) appeared to be less common in rural community patients, which implied there would be more light or atypical patients in community than in clinic. Gender, age and marital status were somewhat related to the occurrence of some symptoms, but other socio-demographic variables were not.4. The rate of suicidal ideation and attempt in rural MDE patients was 37.2%, and the rate of only suicidal attempt was 7.3%. These prevalences were lower compared with previously reported in clinical MDE patients. The rate of suicidal ideation and attempt was higher in female (40.5%) than in male (31.4%). The main related factors to suicidal ideation or attempt were marital status and other depressive symptoms including diminished interest or pleasure and fatigue or loss of energy.5. The utilization of mental health services was considerably poor in rural patients with depression in Liuyang, and most of them have never sought help. There were only a few patients were distinguished, diagnosed or treated when sought help in formal medical institutions. Most of those diagnosed patients were treated with non-psychiatric drugs or alternative medicine, but rarely received antidepressants or any other professional treatment such as psychotherapy.6. The factors related to the utilization of health services were gender, age, occupation, education level, family type, income per capital of the family, occupation and education level of the decision maker in family.LIMITATIONSThis was a cross-sectional study, and there would be recall bias because the patients with past MDE were diagnosed based on the information by their memory. The related factors were mostly the situation in the last year. Therefore, they could not always reflect the status before the onset of depression. The results of cross-sectional study could only indicate there is a statistical association between the factors and the outcomes, but could not confirm their causal relationship.In the study on the symptom characteristics of MDE, some common somatic symptoms, such as pain, gastrointestinal disorders, alpitation and so on, were not examined for the restriction of the structure of SCID. The research on the related factors of symptoms was not so exhaustive, either. Although the sample size of this study was fairly large compared to other similar domestic or overseas epidemiologic surveys, some variables of help-seeking behaviors such as diagnosis delay, treatment delay and habilitation treatments situation could not be analyzed statistically or had a poor statistical efficacy. Because there were only a few of them had ever been distinguished, diagnosed or treated formally, since the very low level of utilization of mental health services among the rural community patients with depression.SIGNIFICANCES AND INNOVATIOSThis research utilized the screening instruments and diagnostic criteria which are widely used around the world to assess the prevalence, distribution characteristics of depression and its related factors, to identify the symptom characteristics and its related factors of patients with MDE, especially with suicide ideation and attempt, as well as to explore the status of health care utilization and its related factors among patients with depression in rural community in China. It complements the studies in this area that usually carried out in clinical patients.It is the first time to study the help seeking delay and related factors of depression patients in rural community in China. Based on both our study results and related literatures, we put forward the health care utilization model of Chinese rural patients with depression for the first time, and could provide lots of reasonable suggestions to depression prevention and treatment in China.