Abstract:
Ischemic Heart Disease (IHD) occurs to a greater extent in developed than
developing countries like Pakistan. Our understanding of risk factors leading to this
disease thus are largely derived from studies carried out on samples obtained from
developed countries. Since prevalence oflHD in Pakistan is growing, it seems
pertinent to compare risk factors across nations that have IHD prevalence. The present
study therefore investigated psychological, social, behavioural and self-reported
family history of IHD, disease history and anthropometric factors for the possible
early onset of IHD in Pakistan. The psychological factors explored were stressful life
events, perceived stress, depression, anxiety, hostility, anger, locus of control and
optimism; social factors included monthly family income, education, perceived social
support and social dominance; behavioural factors were smoking, number of
cigarettes smoked daily and ex-smoking status, alcohol intake, physical activity and
dietary patterns; self-reported disease history, included family history of IHD,
diabetes and hypertension; and anthropometric variables that included waist
circumference, Body Mass Index (BM1) and Waist Hip Ratio ( WHR). Case-control
research design was employed, with a purpose a sample of 190 cases and 380 age and
gender matched community controls who ranged in age from 35 to 55 years were
recruited from five hospitals in Lahore city that run a coronary care unit or equivalent
cardiology ward. The investigator carried out a preliminary study before the main
study to translate, validate and assess reliability of a number of psychometric
instruments, which included; Checklist of Stressful Life Events by (Rosen gren, 2004);
Perceived Stress Scale (PSS) developed by Cohen, Kamarck, and Mermelstem
(1983); RadlofT(1977) Center for Epidemiological Studies Short Depression Scale
(CES-D 10); State-Trait Anxiety Inventory (STAI) (Trait anxiety scale) developed by
Spielberger (1983); State-Trait Anger Expression Inventory (STAXI) (Trait anger
scale) again developed by Spielberger (1999); Life Orientation Test (LOT-R) by
Scheier, Carver, and Bridges (1994); six itemed Percicved Locus of Control Scale
(PLCS) by Bobak, Pikhart, Hertzman, Rose, and Marmot (1998 & 2000);
Multidimensional Scale of Perceived Social Support (MSPSS) by Zimct, Dahlem,
Zimet and Farley (1988); and Personality Deviance Scales (PDS & PDS-R) developed
by Bedford and Foulds, (1978), To ensure rigorous process of forward and backward
translation and to achieve equivalence between the original version and translated
versions of scales, Vallerand’s steps (1989) for instrument translation with slight
modification were employed to decrease risks of errors and improve the precision of
translations (see Figure 22, pp. 129-130).
Binary logistic regression analyses models were run according to the proposed
hypotheses by taking into account overall data; data of men cases and controls, as
well as that of women cases and controls separately. The author also carried out
Multivariate Odds Ratios (ORs) and 95% Confidence Intervals (CIs) for
psychological, social, behavioural, family history of IHD and self-reported physical
health factors (diabetes and hypertension) and anthropometric factors. Odd ratios
represented the excess risk of exposure to a factor in cases compared with controls,
without exposure. Results of the study revealed that psychological factors like
stressful life events and hostility are directly associated with risk of IHD; and
optimism and locus of control were significantly correlated to protective factors of
IHD. Trait anger in women w as found to be associated with risk of IHD. Social
factors like social support and higher level of education were negatively associated
with IHD and were proposed to play a protective role especially with regards to
disease onset, Among behavioural factors smoking, smoking 20 or more cigarettes
daily, and even ex-smoking, significantly associated with IHD, and so did
atherogenic diet rich in {eggs, salt, red meat etc.) and low in (fruits and fish) were
found to be significantly associated with IHD. However useful level of 4 or more
hours of physical activity per week was associated with reduced risk of IHD in men.
Family history of IHD and diabetes were found to be fairly significant risk factors for
men. Furthermore 25 or greater BMI was found to be significantly associated with
risk of IHD in both men and women. In addition WHR > 0.84 was found to be
significantly associated with risk of IHD in women but not in men. Implications for
future research and primary and secondary interventions are being proposed. The
study highlights two major challenges for future research. Firstly, for carrying out
large scale prospective, epidemiological, longitudinal as well as interventional studies
to be tailored for indigenous population and secondly development and
standardization of self-reported measures to appraise psychosocial and behavioural
factors of IHD prevalent within the indigenous population. In the light of present
findings the author proposes a model for primary and secondary prevention of IHD.
Primary prevention highlights (a) public health community based approach and (b)
high risk hospital based strategies, and the secondary prevention approach provides an
overview of hospital as well as community based preventive programs.