PSYCHOSOCIAL AND BEHAVIOURAL RISK FACTORS OF EARLY ONSET ISCHEMIC HEART DISEASE

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.