Prevalence and incidence of arterial hypertension and its risk factors in the 7,525 person-years Congolese adult population between 2012 and 2019 : results of the Bukavu observational study.

Background: In the Sub-Saharan African region, data on Arterial Hypertension (AHT) from longitudinal studies are scattered.This work analyzes the prevalence and incidence of AHT and its associated factors in an open cohort of Congolese adults in South Kivu.

Methods: Between 2012 and 2019, 2,633 subjects aged ≥ 15 years were monitored for at least 3 years. Baseline and follow-up included blood pressure (BP) measurements. AHT was defined as BP of at least 140/90 mmHg or intake of antihypertensive medication in patients with known AHT. Cox regression was used to analyze the association between risk factors and risk of AHT.

Results: The prevalence of AHT increased from 24.8% to 29.0% and the proportion of controlled hypertensive participants rose from 46.9% to 56.6% (p=0.03). During the 7,525 person-years observation period, the incidence of AHT among 1,981 participants without AHT at baseline was 19.4/1000 person-years. The annual incidence of AHT (2.4% per year) was higher in urban (5.0% per year) than in rural areas (2.0% per year). The strongest determinants for incident AHT (p<0.05) were male gender [adjusted HR (aHR)=1.67 (1.08-2.59)], age between 40-59 years [aHR=2.26 (1.48-3.45)], age ≥ 60 years [aHR=3.53 (2.11-5.93)], urban residence [aHR=3.37 (2.07-5.50)], pre-hypertension [aHR=1.77 (1.16-2.70)], abdominal obesity [aHR=1.99 (1.29-3.07)] and smoking [aHR=2.01 (1.12-3.60)].

Conclusion: The present study shows that the prevalence and incidence of AHT are increasing in the Congolese general population. Consequently, improved strategies for the prevention and management of non-communicable diseases are very important in Sub-Saharan Africa.