Prevalence of Depression and Its Associated Risk Factors in the Primary Care Setting in Kuantan

Aims: To determine the prevalence of depression and its associated risk factors among adults attending primary care clinics in Kuantan. Study Design: Cross-sectional. Study: Methodology: The respondents were selected through simple random sampling among adult attendees of public primary care clinics in Kuantan, Pahang. The Malay validated version of Brief Patient Health Questionnaire (PHQ-9) was administered as a screening tool for depression. A part from social-demographic data, we also obtained information on medical illnesses and history of substances abuse. A total of 502 patients were approached and 452 respondents agreed to be enrolled in the study. Results: The study found that 10.6 percent of them were having [1.662, 992.291]). Conclusion: Adults with history of drug abuse or those who suffered from chronic illnesses have higher risk of suffering from depression and need greater attention from primary care providers.


INTRODUCTION
Many psychiatric morbidities including depression are seen at the primary care clinics [1,2] but almost one third of the cases remain undetected [3,4]. One of the contributing factors to this problem is that patients tend to present at primary care clinic with physical symptoms and overt psychological symptoms [5]. This makes the diagnosis of psychiatric morbidity difficult. The ability to identify risk factors related to depression helps doctors to identify and treat the illness.
Depression is characterized by persistent feeling of low mood, inability to experience pleasure, a sense of helplessness, hopelessness, guilt and inhibition of behavior and thinking [6]. It is reported that a lifetime prevalence of depression is between 8-16% [7] and the prevalence of depression in primary care settings is between 5-10% [8]. In any conditions, women suffer from depression more common than men [9].
This study was conducted to determine the prevalence of depression and its associated factors among adults who attended health clinics in Kuantan, Pahang.

METHODOLOGY
Five clinics were selected based on random sampling among all available government clinics in Kuantan namely: Health Clinic Jaya Gading, Health Clinic Beserah, Health Clinic Balok, Health Clinic Gambang and Health Clinic Bandar. The target populations for this study were adults (18 years till 59 years) in Kuantan district who attended the Primary Care Clinics from 2 nd July to 30 th September 2008.
Data were collected from using a self-administered questionnaire. The questionnaires were administered by a team of investigators headed by a family physician who is the principal researcher. A need-based training was conducted by the investigators to standardize administration of the questionnaire. The team went to these clinics twice a week in rotation.
The Patient Health Questionnaire (PHQ-9) which was developed by Robert L Spitzer and colleagues was used as a screening tool for depression. . It was developed from the Primary Care Evaluation of Mental Disorders Patient Health Questionnaire (PRIME-MD PHQ). It is a self-reported questionnaire and consists of nine questions that help to identify depressive symptoms. The PHQ Depression Severity Index score is used to calculate for the presence of depressive symptoms [17].
The Malay validated of PHQ-9 was used in this study. This PHQ-9 contains nine items and has a maximum computed score of 27 points. A review of study in 2004 by Azah confirmed that the optimization of sensitivity and specificity of the PHQ-9 for screening cases was achieved at a case cut-off score of 5 or more for depression with sensitivity of 69.0%, specificity of 60.5%. The best cut-off score for severe depression was 10 with sensitivity of 60.9%, specificity of 80.7% and positive predictive value of 38.6% [18]. In this study, the cutoff score of 10 or more had be selected as the cut-point of depression.

RESULTS
A total of 502 patients were selected through simple random sample and 452 respondents agreed to be enrolled in the study. The inclusion criteria were literate and aged between 18 years to 59 years old. Those refused to give consent or illiterate were excluded from the study. One hundred and five (23.2%) of them were current smoker, three (0.7%) had history of drug abuse and eleven (2.4%) had history of recent alcohol consumption. Among the respondents, women were more likely to be younger, unemployed, nonsmokers, not involved in drug abuse and not consumed alcohol.
In this study, only 21.7% of them suffered from chronic health problems such as Diabetes Mellitus and Hypertension. Screening of depression using the Patient Health Questionnaire (PHQ)-9 revealed that 48 respondents were depressed which showed a prevalence of depression as 10.6 percent. Of these 48 respondents, 26 (54.2%) were males and 22 (45.8%) were females.
Tables 2 shows the association between depression and others factors. Majority of the depressive respondents were married, had secondary or higher educational background and self-employed/private sector. The depression also was found significantly associated with history of chronic illness and social life events such as consumed alcohol and drug abused.

DISCUSSION
Results of the present study show that 48 respondents were having depression which made the prevalence of depression in primary care as 10.6 percent. This percentage is comparable with previous local studies using PHQ screening instrument in which, the past studies the prevalence of depression were 8.3 % 16 and 14.4% [15].
Furthermore, the prevalence of depression in the community under study is almost similar to previous studies done in 15 countries in the world which reported to have a prevalence of 10.4% [19]. However this is lower than the prevalence of national psychiatric morbidity of 11.2% [10].
In this study, there is a significant association between presence of depression and chronic illness among the respondents. There are 37.5% depressive patients among those suffered from chronic medical illness which majority of them suffered from Diabetes Mellitus and Hypertension. This study also has proven that chronic illness is a significant risk factor for depression with a 2.7 times risk to develop it.
Studies in the past showed that the prevalence of depression was higher among females compared to males with an estimated relative risk of 1.93 [20,21]. However, in our study it shows that there is no significant difference between genders and the prevalence of depression. This could be due to selection bias as we could see the number of male participants participated in this study were higher as their counterpart. Generally, we know females have higher tendency to use the primary health facilities.
The same study it is also noted that there is a significant relationship between ethnic groups and depression [21]. Our recent study shows no significant difference between the nonminority and minority ethnic groups in relation to depression. This could be due to skewness in the distribution of subjects according to their race and gender.
In a study done in United States, there were a significant relationship between unemployment and low education level with depression [21] but there are no significant associations between depressions and both factors in our study.
This study had noted that there is no significant association between marital status and depression among the population. As compared to previous study, separated or divorced couples have a significant association with depression [21]. This could be due majority of depression in this study was among married participants which contribute to no significant association with depression in marital status.
It has been widely accepted that substance abuse such as smoking, drug abused and alcohol abused can lead to depression as it involves not only the person himself, but it can also affect other family members and the society. Substance abuse may also affect the socioeconomic status and further deteriorates the mental status of an individual. A significant of relationship is also seen in this study between alcohol and drug abuse with depression. However this is not seen with smoking. The prevalence of smoking and alcohol consumption in present study are lower than expected (23.2% and 2.4% respectively).
Among the various risk factors studied, chronic illnesses, history of recent alcohol consumption and active drug abuse have significant association with depression. On further multivariate analysis shows only those with recent alcohol consume or presence of chronic illness has a significant association with depression with high risk to develop depression of 39.1 times and 2.7 times respectively.

CONCLUSION
The prevalence of depression in this study was 10.6% and the presence of chronic illness and social factors such as history of drug abuse and recent history of alcohol consumption in this study are identified as the risk factors for depression among adults attending the primary care clinics in Kuantan, Pahang. Therefore, those with those histories and presence of chronic illness should be given more attention by the health workers and the community.
Identifying risk factors for depression may help primary care providers to improve the early detection of depression, which is a critical first step towards effective management.

STUDY LIMITATION
We identified a few limitations in this study. Firstly the distribution of subjects is not according to actual Malaysian population according to their races and gender. Malays and male gender are overrepresented in this study. Secondly, although the questionnaire used has been validated, but depending on a single self-rated measurement is subject to recall bias. It is good if the cases could be screen based on clinical judgment by a few qualified psychiatrists. However the selection and recall bias have been addressed by using simple random sampling and standardization among the raters.

CONSENT
The agreement of consent was obtained in all patients.

ETHICAL APPROVAL
The authors hereby declares that this study was approved by the Research and Ethics Committee of Kulliyyah of Medicine, International Islamic University Malaysia and it has been performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki.