Examination of a Culturally Sensitive Dietary Education Intervention to Treat Hypertension for Chinese Canadians in the Community: A Pilot Randomized Controlled Trial

Numbering about 1.3 million, the Chinese compose approximately 3.9% of Canada’s population and roughly 24% of the country’s visible minorities. The hypertension prevalence rate of Chinese Canadians reaches 15.1%. Hypertension has been identified as the most important risk factor for cardiovascular diseases and accounts for a large proportion of stroke, myocardial infarction and heart failure in the Chinese population. While unhealthy diet has been identified as a modifiable risk factor for hypertension, there is a lack of culturally sensitive dietary intervention targeting Chinese Canadians. The primary research objective was to determine the feasibility of the Dietary Approach to Stop Hypertension with Sodium (Na) Reduction for Chinese Canadian (DASHNa-CC) intervention. Secondary objectives were to examine its potential effects on blood pressure, health-related quality of life, and health service utilization. This study was a pilot randomized controlled trial, with a sample size of 60, in a Chinese Canadian community in Greater Toronto Area. Self-identified Chinese Canadians, older than 45 years old and with grade one hypertension, were included in this pilot randomized controlled trial. The control group received usual care and the intervention group received usual care plus the DASHNa-CC intervention. The 8-week DASHNa-CC intervention incorporated Dietary Approach to Stop Hypertension (DASH) diet, sodium reduction with the food therapy of Traditional Chinese Medicine, and included an intervention manual, two sessions of classroom instruction delivered in Mandarin, and 20-minute telephone follow-up. Descriptive statistics and t-tests were used to analyze the data. In a Chinese community in Toronto, 618 Chinese Canadians participated in blood pressure screening, 54.5% (n = 337) had hypertension, and 17% (n =105) were eligible to participate in this pilot trial study. Among eligible individuals, 60 (57.1%) consented to participate. Participants adhered well to the DASH diet pattern, sodium reduction and TCM food therapy strategies. The lost to follow-up rate was 5%. Participants were highly satisfied with the intervention and perceived that intervention contents were helpful, delivery approaches were suitable, participation in this pilot trial brought them benefit rather burden on their lives. Compared to the control group, the intervention group had greater systolic blood pressure reduction. At week eight post randomization, while the control group decreased 6.9 mmHg and 3.1 mmHg on systolic and diastolic blood pressure, the intervention group decreased 10.7 mmHg and 5.5 mmHg respectively. Compared to the control group, the intervention group decreased 3.8 mmHg [t (55) = -1.58, p = 0.12] more on systolic blood pressure and 2.4 mmHg [t (55) = -1.22, p = 0.23] more on diastolic blood pressure. Although these blood pressure reductions were not statistically significant, they were clinical important to reduce hypertension-related mortality and morbidity. In relation to health-related quality of life, the intervention group had a significant improvement from baseline to week eight post randomization in physical component score [t (55) = 2.13, p = 0.04]. There was no group difference regarding the use of various health care services. It is concluded that it is feasible to conduct a DASHNa-CC trial in a Chinese community. The DASHNa-CC intervention has potential to decrease systolic and diastolic blood pressure, and improve health-related quality of life for Chinese Canadians. A powered randomized controlled trial should be undertaken to further investigate the effectiveness of the intervention.Ph.D