Dietary intake and barriers to dietary compliance in black type 2 diabetic patients attending primary health-care services.

Abstract

To determine the dietary intake, practices, knowledge and barriers to dietary compliance of black South African type 2 diabetic patients attending primary health-care services in urban and rural areas. A cross-sectional survey. Dietary intake was assessed by three 24-hour recalls, and knowledge and practices by means of a structured questionnaire (n = 133 men, 155 women). In-depth interviews were then conducted with 25 of the patients to explore their underlying beliefs and feelings with respect to their disease. Trained interviewers measured weight, height and blood pressure. A fasting venous blood sample was collected from each participant in order to evaluate glycaemic control. An urban area (Sheshego) and rural areas near Pietersburg in the Northern Province of South Africa. The sample comprised 59 men and 75 women from urban areas and 74 men and 80 women from rural areas. All were over 40 years of age, diagnosed with type 2 diabetes for at least one year, and attended primary health-care services in the study area over a 3-month period in 1998. Reported dietary results indicate that mean energy intakes were low (< 70% of Recommended Dietary Allowance), 8086-8450 kJ day(-1) and 6967-7382 kJ day(-1) in men and women, respectively. Urban subjects had higher (P < 0.05) intakes of animal protein and lower ratios of polyunsaturated fat to saturated fat than rural subjects. The energy distribution of macronutrients was in line with the recommendations for a prudent diet, with fat intake less than 30%, saturated fat less than 10% and carbohydrate intake greater than 55% of total energy intake. In most respects, nutrient intakes resembled a traditional African diet, although fibre intake was low in terms of the recommended 3-6 g/1000 kJ. More than 90% of patients ate three meals a day, yet only 32-47% had a morning snack and 19-27% had a late evening snack. The majority of patients indicated that they followed a special diet, which had been given to them by a doctor or a nurse. Only 3.4-6.1% were treated by diet alone. Poor glycaemic control was found in both urban and rural participants, with more than half of subjects having fasting plasma glucose above 8 mmol l(-1) and more than 35% having plasma glycosylated haemoglobin level above 8.6%. High triglyceride levels were found in 24 to 25% of men and in 17 to 18% of women. Obesity (body mass index > or = 30 kg m(-2)) was prevalent in 15 to 16% of men compared with 35 to 47% of women; elevated blood pressure (> or = 160/95 mmHg) was least prevalent in rural women (25.9%) and most prevalent in urban men (42.4%). The majority of black, type 2 diabetic patients studied showed poor glycaemic control. Additionally, many had dyslipidaemia, were obese and/or had an elevated blood pressure. Quantitative and qualitative findings indicated that these patients frequently received incorrect and inappropriate dietary advice from health educators.