Dietary factors and hypertension risk in West Africa: a systematic review and meta-analysis of observational studies

Abstract

Background: Contrary to North America and Europe, the prevalence of hypertension is rising in West Africa. Although diet is implicated as a contributor to this trend, nutritional guidelines in West Africa are not tailored to address this concern. This study aimed to address this limitation by investigating dietary factors common to West Africa and evaluating their association with hypertension. Methods: PubMed, Scopus, Web of Science, and Medline were searched to identify studies that investigated diet and hypertension in West African adults. All meta-analyses used a generic inverse-variance random effects model, with subgroup analyses by age, BMI, and study location, and were performed in R. Results: Three thousand, two hundred ninety-eight studies were identified, of which 31 (n = 48 809 participants) satisfied inclusion criteria – all cross-sectional. Meta-analyses of the association between dietary factors and hypertension included dietary fat [odds ratio (OR) = 1.76; 95% confidence interval (95% CI) 1.44–2.14; P < 0.0001], red meat (OR = 1.51; 95% CI: 1.04–2.18; P = 0.03), junk-food (OR = 1.41; 95% CI: 1.19–1.67; P < 0.0001), dietary salt (OR = 1.25; 95% CI: 1.12–1.40; P < 0.0001), alcohol (OR = 1.17; 95% CI: 1.03–1.32; P = 0.013), and ‘fruits and vegetables’ (OR = 0.80; 95% CI: 0.24–1.17; P < 0.0001). Subgroup analyses suggested that ‘fruit and vegetable’ consumption is less protective in the elderly. Conclusion: High consumption of dietary salt, red meat, dietary fat, junk food, and alcohol are associated with increased odds of hypertension, whereas high fruit and vegetable appear protective. This region-specific evidence will support the development of nutritional assessment tools for clinicians, patients, and researchers aiming to reduce hypertension in West Africa.

Validity and reproducibility of a culturally tailored dietary screening tool for hypertension risk in Nigerian healthcare

“…Furthermore, the Bland-Altman analysis was used to assess the level of agreement between the FFQ and 24DR ( S3 Table ). Fig 3A-F presents the Bland-Altman plots for the 3 healthy food groups of the DASH diet (e.g., fruits, vegetables, and nuts and seeds) [42] and 3 less healthy food groups/items identified by our recent meta-analysis of foods associated with hypertension in West African countries, including Nigeria [12] (e.g., salt, fried/fast foods, and fats and oils). The plots for the remaining food groups are provided in supplementary materials ( S1 Fig).…”

“…The validity and reproducibility of our study data provide compelling evidence to further investigate the implementation and use of our novel FFQ as a practical clinical tool to screen and evaluate patient-mediated dietary risk for hypertension. The FFQ was able to rank intakes in food groups associated with hypertension [11, 12], including fruits, vegetables, grains, dairy, salt and fats and oil-based foods (soups and stew), to a similar degree of accuracy as 24DR, but was able to be completed in < 20 minutes. The results indicate that the FFQ can identify patients with high-risk dietary patterns who may benefit from prioritised education and support around dietary modification for blood pressure management.…”

“…The dietary screening tool was a newly developed, 27-food group semi-quantitative food frequency questionnaire (FFQ) that was designed to capture the usual food intake over the past month. The initial list of commonly consumed foods was created through guidance from the Nigerian and Ghana National Nutritional Guideline on Non-Communicable Disease Prevention, Control and Management [27, 28] and supported by our prior systematic review and meta-analysis the investigated dietary factors associated with hypertension in the West Africa [12]. Designed to be completed in less than 20 minutes, the final FFQ comprised 26 questions on major food groups and an additional 6 questions related to salt ( S1 Table ).…”

“…Moreover, deficiencies in vital dietary components like fruits, vegetables, nuts, legumes, and omega-3 fatty acids from seafood correlate with elevated blood pressure levels [11]. In our prior research, we highlighted a significant association between high consumption of diets rich in dietary salt, red meat, processed foods, fried foods, dietary fat, and alcohol and an elevated risk of hypertension with a mean overall risk increase of 1.42 not only in Nigeria but also in various West African countries [12]. The average daily sodium intake in Nigeria ranges from 9-12 grams, which exceeds the World Health Organization’s (WHO’s) recommended limit of 5 grams [13].…”

Dietary patterns and the risk of cardiovascular diseases

“…However, mixing fruit juice with sugar-sweetened beverages (up to ∼23%) moderately increases blood pressure while removal of sugar-sweetened beverages decreases blood pressure irrespective of the presence or absence of hypertension (Liu et al, 2023). Consistently, another observational study from West African countries reported that higher consumption of red meat, dietary fat, salt, junk food, and alcohol are linked with increased blood pressure and hypertension while higher consumption of fruit and vegetables was protective against hypertension (Batubo et al, 2023).…”