The Effect of Educational Intervention on the Nutritional Knowledge, Illness Perception and Dietary Adherence in Middle-Aged Women with Hypertension: Application of the Transtheoretical Model

Cardiovascular diseases are the most common cause of death in most countries of the world, hypertension being the most important cause of disability. The aim of this study conducted in 2020-2021 was to determine the effect of educational intervention on the nutritional knowledge, illness perception and dietary adherence in hypertensive middle aged women based on the transtheoretical model (TTM).

This was a quasi-experimental study on middle-aged women (30-59 years old) suffering from hypertension referred to the  health centers and health bases in the 21st district of Tehran in 2020-2021. A total of 164 subjects were randomly assigned to the intervention (n=82) or control (n=82) group by randomized quadruple blocks. A multifaceted questionnaire was completed for both the control and intervention groups and their blood pressure measured. This was followed by  a one-month virtual education for the intervention group in the form of a WhatsApp group and designing and developing fifty-six podcasts and educational clips with a maximum duration of four minutes based on the transtheoretical model constructs. After a lapse of one and six months both groups completed the questionnaire again and their blood pressure was measured. Descriptive statistics and general linear model were used for data analysis using the SPSS version 25 (p<0.05).

Before the intervention the mean age of the subjects was 50.16 years and their systolic and diastolic blood pressures were 1.35 and 1.84 mmHg, respectively, and there were no statistically significantly differences between the two groups as regards contextual variables, constructs of nutritional awareness, disease perception, diet adherence, systolic and diastolic blood pressures and body mass index (as an ananthropometric index) and transtheoretical model constructs. Data one month after the intervention revealed significant differences (p<0/001) between the two groups (p <0/001) as regards the constructs of nutritional awareness, disease perception, self-sufficiency construct of the transtheoretical model and systolic blood pressure. Six months after the intervention significant differences were observed between the two groups as regatds  nutritional awareness constructs, disease perception (p<0.007), diet adherence (p<0.001), stages of change constructs (p<0.001) and self-sufficiency (p<0.001) of the transtheoretical model.

The results of this study show that educational intervention based on the transtheoretical model in middle-aged women with hypertension can increase their nutritional knowledge, illness perception, self-sufficiency, self-adequacy and diet adherence.