Detection and characteristics of hypertension patients admitted in 37 cardiology departments from 17 Sub-Saharan African countries

Background

High blood pressure (BP) is a major risk factor for several common cardiovascular (CV) disease such as stroke, heart failure or chronic kidney disease. The Sub-Saharan Africa (SSA) should face the highest rate of hypertension worldwide with an overall prevalence estimation of 46%. Due to scarce resources and inadequate healthcare provision, SSA have scarce hard data on treatment and control of high BP.

Purpose

To assess the detection and characteristics of hypertension patients admitted in hospitalizations 17 SSA countries

Methods

We conducted a transversal and longitudinal study in CV department of 37 hospitals from 23 cities in 17 SSA countries (10 low income: Niger, Guinea, Benin, Mali, Democratic Republic of the Congo, Tchad, Burkina Faso, Togo, Burundi, Ethiopia and 7 middle income: Cote d'Ivoire, Senegal, Cameroon, Congo, Soudan, Mauritania, Gabon). The February study was designed by a multidisciplinary collaborative team of epidemiologists, pharmacists and cardiologists from Africa and France. This ongoing observatory included all inpatients in February from each year since 2016. Data including socio-demographic and clinical characteristics, causes of admission, clinical, biological, complementary examinations, treatments, length of stay and discharge diagnosis were collected by the investigating physicians. Hypertension and severity of hypertension were defined according to 2018 ESC/ESH guidelines and BP was measured twice using standardized method. All analyses were performed through scripts developed in the R software (4.0.3 (2020-10-10))

Results

The study involved 4360 patients. Hypertension was measured on 1906 (43.7%) patients at admission. Proportion of patients with high BP in hospital increased from 42.2% in 2016 to 52.2% in 2021 (p<0.05) and differed significantly across countries from 77.6% in Niger to 100% in Chad. Among hypertensive patients, men represented 59.6% of patients and mean of age was 59±15.1 years. Overall, 61.4% of patients were from low income countries. The mains causes of admission among hypertensive patients were heart failure (37.8%) and stroke (18.9%). Average of systolic BP was 159±29.3 mmHg and average of diastolic BP was 96.7±16mmHg. Overall, 760 (40.3%), 525 (27.8%) and 602 (31.9%) had grade 1, grade 2 and grade 3 hypertension respectively. History of CV disease was observed in 51.5% of patients. Thus, 70.4% of patients had at least one CV risk factor other than hypertension. Angiotensin converting enzyme inhibitors and diuretics was prescribed in 56.9% and 55.8% of patients respectively. The average amount of antihypertensive drugs prescribed in hospital was 2.09±1.18. Overall, 237 (12.4%), 295 (15.5%), 640 (33.6%) and 734 (38.5%) received respectively no drug, monotherapy, two-drug strategies and three and more drug strategies.

Conclusion

In patients admitted in cardiology departments, hypertension is a huge burden in SSA.

Funding Acknowledgement

Type of funding sources: None.

Seasonal variation of ticks on cattle in Burkina Faso

Cattle of the Sahel Zebu peuhl breed from traditionally managed livestock herds in a representative area of north soudanese savana (with 400-900 mm of rainfall/year from May to September) located in the central land of Burkina Faso, were monitored over 12 months for tick and blood parasite. Two species of ticks were found: Amblyomma variegatum and Hyalomma marginatum rufipes. H. m. rufipes was found on cattle all year round with a highest infestation rate in June characterized by means of 10 +/- 4.72 male and 3 +/- 2.43 female ticks per animal. A variegatum appeared on cattle at the beginning of the rainy season in May and quickly reached its highest infestation rate in June with means of 36 +/- 3.67 male and 16 +/- 1.54 female ticks per animal. Thereafter, the infestation rate progressively decreased to reach almost zero in October at the end of the rainy season. There were three preferred body sites for attachment: the axilla area, the area of the scrotum or the udder and the teats depending on the sex of the animal, and the anal area. No blood parasites were found in blood smears. However, a higher prevalence rate of dermatophilosis was noticed on highly infested animals during the rainy season as well as wounds on teats leading to decreased milk production and feeding of calves. Effort should be done to fight against ticks of Amblyomma genus at the period of the year where they are most numerous. Manual removal of ticks could be practiced, making certain to completely detach all mouthparts of the ticks. Complete removal of ticks will avoid wounds and secondary bacterial infections as well as myiasis. During the period of highest prevalence, the rainy season, acaricides could be applied on animal either by dipping the animals or spraying on the predilection sites of the ticks which are the axilla, the scrotum or the udder and the teats, depending on the gender of the animal, and around the anus.

Etiology and prophylaxis of helminthiasis in sheep in Burkina Faso

Helminths of "Mossi" sheep from traditional livestock were investigated at three different seasons (humid, cold dry, and hot dry seasons) in the village of Donsin from the central land of Burkina Faso. Three prophylaxis plans using Fenbendazole were tested. Primary parasites identified were: Oesophagostomum sp., Trichostrongylus sp., and Haemonchus contortus. These parasites were noticed mainly during the rainy season with mean egg per gram (epg) numbers of 500 +/- 141.42 in August-September, at the end of the rainy season. At this same period, hematocrit (22%) and body weights (17 kg of live weight) (LW) were low. These values progressively increased to reach their highest levels (32% and 27 kg of LW respectively) in February. The prophylactic plan consisting of two treatments with oral drench of 5 mg/kg LW of Fenbendazole turned out to be the most efficacious and the most economical.

Comparative evaluation of the prophylactic effect of slow release devices containing homidium bromide and isometamidium on Trypanosoma congolense in rabbits

Two consecutive experiments were carried out to evaluate the prophylactic effect of biodegradable slow release devices (SRD), containing either isometamidium or homidium bromide. Rabbits subcutaneously implanted with SRD, were challenged with different Trypanosoma congolense stocks at regular intervals between 1 and 6.5 months after treatment. In a first experiment the efficacy of two types of isometamidium-SRD (poly(D,L-lactide) and poly(D,L-lactide-co-glycolide)) was compared with the classical intramuscular (i.m.) injection of the drug. Since the former polymer gave an average protection period, which was much longer than the other isometamidium formulation, a second experiment was carried out to evaluate the prophylactic effect of poly(D,L-lactide) SRD, containing either isometamidium or homidium bromide, with that of the i.m. injections of the same drugs at a dose of 1 mg kg-1. The average protection period of the homidium bromide SRD was significantly longer than that of the i.m. injected drug (112 vs. 49 days). No significant difference was obtained, however, when isometamidium was administered either as a SRD or as an i.m. injection. The average protection periods were, respectively, 106 +/- 37 days and 84 +/- 18 days. When breakthrough isolates derived from SRD-treated animals were compared with the original stocks of T. congolense, the former showed some loss of sensitivity to homidium bromide. No difference in sensitivity was observed, however, for isometamidium.