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a study , performed by the national heart association of malaysia , has reported that the majority of coronary heart disease ( chd ) patients are in their forties and fifties .
it has also been reported that chd is a major cause of premature deaths in malaysia , and has significant psychosocial and economic implications for the country . the anxiety and depression of chd patients
have significant impact on their compliance with treatment , and prognosis . the preconceived ideas and past problems experienced by the patients may exacerbate their physical symptoms , and
studies have reported that chd individuals are prone to suffer from mood labile , and end up with overt depression .
a previous study has revealed that 33 - 64% of chd patients experienced severe emotional reactions in the first four months after a heart attack .
in addition , there was an increased cardiac mortality in patients who developed post - myocardial infarction depression , while pre - myocardial infarction depression did not carry any additional risk of mortality .
moreover , in post - acute myocardial infarction ( ami ) patients assessed using hospital anxiety and depression score ( hads ) , 13.6% showed moderate and severe anxiety , and 7.3% showed moderate or severe depression at the end of three months . anxiety and depression were frequent problems encountered by the chd patients .
it has been shown that anxiety and depression strongly affect overall well - being , cardiac and non - specific symptom reporting , and overall quality of life .
this has been reported as a convergent evidence supporting the role of emotional stimuli in triggering off acute coronary syndrome ( acs ) , unstable angina and myocardial infarction .
emotional upsets often trigger off the pathophysiological changes underlying plaque rupture , formation of a prothrombotic vascular environment , thrombus formation , and other neuroendocrine and autonomic processes , which results in cardiac rhythm disturbances . confounding psychosocial factors
significant confounding factors include depressive and anxiety disorders , anger , hostility and chronic life stressor .
other confounding factors include low socio - economic status , poor social support , work stress , and marital problems .
the working environment can be a risk factor for the development of severe depressive symptoms , and depend on gender , other different factors might play a role as well .
furthermore , reviews of depression and chd suggest a causal relationship between depression and risk of adverse cardiovascular outcomes .
studies have documented that treatment of depression in cardiac patients reduces cardiac disease symptoms , and decreases patients ' morbidity and disabilities , thereby improving the quality of life .
poor adjustment to a chronic illness can lead to depression and anxiety as well as functional declines .
although some patients may subsequently adjust to a new or progressing illness , others continue to exhibit symptoms of depression , anxiety , and impairment .
subsequently , depression is associated with reduced adherence to medication , reduced participation and increased drop - out rates in cardiac rehabilitation programs , which encourage lifestyle changes .  
the objective of the present study was to assess the anxiety and depression in chd patients in order to identify potential problems , and to recommend appropriate interventions for assessment and support .
this was a cross - sectional study conducted on 108 chd patients in universiti kebangsaan malaysia medical center ( ukmmc ) .
the study was approved by the institutional ethics and research committees ( ff-019 - 2009 ) .
all of the chd patients , who were hospitalized in the coronary care unit from march to december 2008 , were recruited for the study .
the inclusion criteria were chd patients , who aged above 18 years old and consented to participate in the study .
the chd patients , who had been hospitalized or had history of psychiatric illness were excluded from the study .
two sets of validated questionnaires including hads , and socio - demographic profiles questions were administered to the chd patients . the hads questionnaire was adopted and translated back to local bahasa malaysia language , which was used by malaysian respondents .
a previous study reported that the sensitivity and specificity for english and bahasa malaysia versions of the hads to be approximately 0.80 . in a previous study
it was reported that cronbach 's alphas for anxiety and depression were 0.83 and 0.80 , respectively indicating the reliability of the hads questionnaire .
the hads questionnaire has been widely used to screen depression among cardiac patients in the hospitals .
the hads questionnaire has 2 subscales including anxiety and depression , each of which comprised of items rated on 4-point likert scales .
the total hads score ranged between 0 - 42 with 0 - 14 being considered as low , 15 - 28 considered as moderate , and 29 - 42 being considered as high . for each subscale ( anxiety and depression subscales ) , the scores ranged between 0 to 21 , where 0 - 7 was considered low , 8 - 14 being moderate , while 15 - 21 was considered high . 

statistical analysis 
  descriptive analysis including frequency of the respondents socio - demographic , median and interquartile range ( iqr ) of hads score were used for data analysis .
mann - whitney or kruskal wallis tests were used to analyze the socio- demographic data and hads score of the respondents .
respondents socio - demographic data including gender , age , race , marital status , number of children , education level , occupation , income , and co - morbidity disease are shown in table 1 .
the scores for total hads , anxiety subscale and depression subscale were 8.968.04 , 4.254.30 and 4.714.50 , respectively .
the median score and iqr for hads , and anxiety and depression subscales were as follows ; hads : 6.5 and 14 , anxiety subscale : 3.0 and 7 , and depression subscale : 3.0 and 7 ( table 2 ) .
respondents socio - demographic profiles the meansd and the median of interquartile range ( iqr ) of scores of anxiety and depression subscales and total hospital anxiety and depression scale ( hads ) of the study participants the median of interquartile range ( iqr ) stratified based on socio - demographic characteristics ( gender , age , race , marital status , level of education and co - morbidity of diseases ) of the study participants * indicate significant difference at p value < 0.05 there was no significant difference between the total hads score of the participants stratified based on age ( p=0.178 ) , gender ( p=0.471 ) , race ( p=0.657 ) , education ( p=0.626 ) or income ( p=0.323 ) ( table 3 ) .
however , there was significant differences in the total hads score of participants stratified for marital status ( p=0.027 ) or co - morbidity of diseases ( p=0.012 ) .
in terms of co - morbidity of diseases , respondents with a co - morbid disease has higher hads score than respondents without a co - morbid disease ( table 3 ) .
there were significant differences in the scores of depression subscale stratified for marital status ( p=0.021 ) or co - morbidity of diseases ( p=0.007 ) .
there was no significant difference in the scores of depression subscale stratified based on age ( p=0.268 ) , gender ( p=0.453 ) , race ( p=0.720 ) , education ( p=0.784 ) or income ( p=0.249 ) ( table 4 ) .
the respondents with a co - morbid disease had higher subscale depression score than respondents without a co - morbid disease ( table 4 ) .
these findings are similar to those of an earlier study , which used the hads to screen for anxiety and depression in cardiac patients in the united states .  
the low scores anxiety and depression of chd patients indicates that most of them were coping well .
the chd respondents abilities to accept the condition and restructure their lifestyles after cardiac rehabilitation program may be the possible reason for the low scores .
moreover , the cohesiveness of family and social support may be the contributing factors in adjusting and modifying the essential needs to accomplish the psychological outcome .
earlier studies stated that an environment with good social support from family may have a buffering effect on an individuals coping mechanism .
the median of interquartile range ( iqr ) scores for depression subscale stratified based on socio - demographic characteristics ( gender , age , race , marital status , level of education and co - morbidity of diseases ) of the study participants * indicate significant difference at p value < 0.05 the findings of the study show that unmarried chd patients had a higher level of depression .
several studies have reported similar findings indicating that unmarried status was associated with life dissatisfaction .
it has been reported that the wax and wane of depression mostly reflect life - cycles gains and losses related to marriage , employment , and economic well - being .
furthermore , in our local malaysian setting , individuals are brought up and inculcated family cohesiveness , which includes family values , filial piety , and religious beliefs .
subsequently , the commitment of spouse and family members are pivotal to provide ultimate care and support to individual family members , who are succumbed to chd .   in this study ,
the co - morbid diseases comprised of hypertension , diabetes mellitus , kidney diseases and hypercholesterolaemia .
most importantly respondents , who had other co - morbid diseases , had more signs and symptoms related to their diseases such as easy fatigue , pain , edema , restlessness and breathlessness .
in addition to the burden of co - morbid diseases , the respondents ' situations were exaggerated by the different types of drugs they were prescribed .
these problems might interrupt the daily activities of the respondents , and caused them to feel anxious and more depressed .
other studies have reported that higher level of acute mental stresses have an adverse effect on future cardiovascular risk status . 
 
a recent meta - analysis showed that depression was associated with a 46% increased risk of cardiovascular disease .
the impact of depression on cardiac death ( 55% increased risk ) in the present study was comparable to the impact of anxiety found in that meta - analysis .
several studies also reported that the respondents with both generalized anxiety disorder and major depressive disorder were at the greatest risk of subsequent cardiac death , suggesting that anxiety and depression might also interact synergistically to affect chd . a study reporting on the adolescents exposed to chronic negative stressors that worsened over time showed that cardiovascular reactivity was so heightened that put them at risk for subclinical atherosclerosis . 

the present study showed that scores for psychological indices among the chd respondents were relatively low .
moreover , chd respondents with co - morbid diseases showed a high level of depression .
the findings might imply that chd patients should be evaluated early for the detection of anxiety and depression for appropriate referral and support . a periodic evaluation and appropriate referral
the clinical implication of this study might be that anxiety and depression should be considered a prognostic factor in patients with chd .
anxiety and depression could reduce the quality of life , and exacerbate physical symptoms and even mortality amongst patients with coronary heart disease ( chd ) . 
 the aim of this study was to investigate the incidence of anxiety and depression in patients with acute chd . in a period from march to december 2008 
 , the views of 108 chd patients , hospitalized in a tertiary hospital , were solicited using hospital anxiety and depression scale ( hads ) and sociodemographic questionnaires . patients with chd had a low level anxiety and depression scores . 
 there was significant differences in the total hads score of participants stratified for marital status ( p=0.027 ) or co - morbidity of diseases ( p=0.012 ) . 
 also , there were significant differences in the scores of depression subscale stratified for marital status ( p=0.021 ) or co - morbidity of disease ( p=0.007 ) . 
 however , there was no significant difference between the total hads score or depression subscale score of the participants stratified based on age , gender , race , education , or income . moreover , unmarried chd respondents possessed higher depression level compared to the married respondents , and chd respondents with co - morbid diseases showed a high level of depression . 
 the findings might be taken as evidence to suggest that chd patients should be evaluated early for the detection of anxiety and depression for appropriate referral and support .