Hypertension in a resource-limited setting: Is it associated with end organ damage in older adults in rural Tanzania?

Lack of Association of Vascular Risk Factors with HIV-Associated Neurocognitive Disorders in cART-Treated Adults Aged ≥ 50 Years in Tanzania

HIV-associated neurocognitive disorders (HAND) are highly prevalent in those ageing with HIV. High-income country data suggest that vascular risk factors (VRFs) may be stronger predictors of HAND than HIV-disease severity, but data from sub-Saharan Africa are lacking. We evaluated relationships of VRFs, vascular end-organ damage and HAND in individuals aged ≥ 50 in Tanzania. c-ART-treated individuals were assessed for HAND using consensus criteria. The prevalence of VRFs and end organ damage markers were measured. The independent associations of VRFs, end organ damage and HAND were examined using multivariable logistic regression. Data were available for 153 individuals (median age 56, 67.3% female). HAND was highly prevalent (66.7%, 25.5% symptomatic) despite well-managed HIV (70.5% virally suppressed). Vascular risk factors included hypertension (34%), obesity (10.5%), hypercholesterolemia (33.3%), diabetes (5.3%) and current smoking (4.6%). End organ damage prevalence ranged from 1.3% (prior myocardial infarction) to 12.5% (left ventricular hypertrophy). Measured VRFs and end organ damage were not independently associated with HAND. The only significant association was lower diastolic BP (p 0.030, OR 0.969 (0.943-0.997). Our results suggest that vascular risk factors are not major drivers of HAND in this setting. Further studies should explore alternative aetiologies such as chronic inflammation.

Compliance to hypertensive prescribing guidelines and blood pressure control in elderly patients in Namibia: findings and implications

Objective

Resources-limited countries in sub-Saharan Africa are facing a crisis of hypertensive-related morbidity, mainly due to poor blood pressure (BP) control. The study aimed to evaluate BP control and hypertensive prescribing for elderly patients in a resource-limited setting.

Methods

Hospital-based survey assessing hypertensive prescribing practices among elderly patients (age, ≥60years) at a leading ambulatory care clinic in Namibia. The primary and secondary outcomes were compliance with prescribing guidelines, prescribing patterns and BP control respectively. Data were collected using patient exit interviews and a review of their prescription records. Data were analyzed using descriptive statistics using SPSS v25.

Key findings

Of the 189 elderly patients recruited, 69.3% were females, mean age was 70.3 ± 8.5 years and 2.6% had HIV. 61.4% of the prescriptions complied with the prescribing guidelines in terms of treatment choice and 78.3% (n = 148) had a poor BP control. 61.4% had at least one comorbidity, mainly diabetes mellitus (32.2%) or cardiac disease (20%). On average, 4.5 medicines were prescribed per patient and 4.8% were out of stock. Prevalence of non-INN prescribing was 64%. Diuretics, renin-angiotensin inhibitors were the most prescribed antihypertensive, 73.9% (n = 138/189) and 51.9% (n = 98/189) respectively. 90% of patients with good BP control were on ≥3 medicines compared to 77% for patients with poor BP controlled.

Conclusion

Whilst compliance with prescribing guidelines is modest, the sub-optimal BP control, high prevalence of co-morbidities and over prescribing with non-INN products is discouraging. Pharmacist-led medication audits could improve hypertensive prescribing and BP control among elderly patients, and we will be following this up

Retinopathy in adults with hypertension and diabetes mellitus in Western Tanzania: a cross-sectional study

OBJECTIVE

Little is known about the retinal manifestations of arterial hypertension (HTN) and diabetes mellitus (DM) in Western Tanzania and how to maximise the utilisation of scarce eye health resources. To address this, we determined the prevalence of hypertensive and diabetic retinopathy (DR), associated risk factors and relevant patient knowledge.

METHODS

Adults with HTN or DM attending outpatient clinics at Bugando Medical Center (BMC) from June to August 2017 were enrolled. Fundus photographs were obtained, and data were collected on blood pressure (BP), body mass index (BMI), blood sugar, visual acuity (VA) and responses to questions about the effects of HTN and DM on the eye.

RESULTS

A total of 180 persons were screened. When only individuals with DR were considered, bivariate regression found systolic BP was significantly associated with severity of DR (P = 0.034). Receiver operating characteristic (ROC) curve analysis using the maximum Youden index revealed the optimum cut-off using duration of DM to predict any DR was 8 years (AUC = 0.75, 95% CI 0.65-0.85). Fewer persons with HTN were aware of the effect of high BP on the eye (61.6%) than persons with DM who were aware of the effect of high blood sugar on the eye (74.4%) (P = 0.048).

CONCLUSION

Efforts should be made to vigorously treat HTN among adults with DM and refer adults with duration of DM of 8 years or more for a dilated retinal examination. Additional efforts should be made to promote awareness of the sight threatening potential of HTN in resource-limited settings.

Prevalence of postural hypotension in primary, community and institutional care: a systematic review and meta-analysis

BACKGROUND

Postural hypotension (PH), the reduction in blood pressure when rising from sitting or lying 0to standing, is a risk factor for falls, cognitive decline and mortality. However, it is not often tested for in primary care. PH prevalence varies according to definition, population, care setting and measurement method. The aim of this study was to determine the prevalence of PH across different care settings and disease subgroups.

METHODS

Systematic review, meta-analyses and meta-regression. We searched Medline and Embase to October 2019 for studies based in primary, community or institutional care settings reporting PH prevalence. Data and study level demographics were extracted independently by two reviewers. Pooled estimates for mean PH prevalence were compared between care settings and disease subgroups using random effects meta-analyses. Predictors of PH were explored using meta-regression. Quality assessment was undertaken using an adapted Newcastle-Ottawa Scale.

RESULTS

One thousand eight hundred sixteen studies were identified; 61 contributed to analyses. Pooled prevalences for PH using the consensus definition were 17% (95% CI, 14-20%; I2 = 99%) for 34 community cohorts, 19% (15-25%; I2 = 98%) for 23 primary care cohorts and 31% (15-50%; I2 = 0%) for 3 residential care or nursing homes cohorts (P = 0.16 between groups). By condition, prevalences were 20% (16-23%; I2 = 98%) with hypertension (20 cohorts), 21% (16-26%; I2 = 92%) with diabetes (4 cohorts), 25% (18-33%; I2 = 88%) with Parkinson's disease (7 cohorts) and 29% (25-33%, I2 = 0%) with dementia (3 cohorts), compared to 14% (12-17%, I2 = 99%) without these conditions (P < 0.01 between groups). Multivariable meta-regression modelling identified increasing age and diabetes as predictors of PH (P < 0.01, P = 0.13, respectively; R2 = 36%). PH prevalence was not affected by blood pressure measurement device (P = 0.65) or sitting or supine resting position (P = 0.24), however, when the definition of PH did not fulfil the consensus description, but fell within its parameters, prevalence was underestimated (P = 0.01) irrespective of study quality (P = 0.04).

CONCLUSIONS

PH prevalence in populations relevant to primary care is substantial and the definition of PH used is important. Our findings emphasise the importance of considering checking for PH, particularly in vulnerable populations, to enable interventions to manage it. These data should contribute to future guidelines relevant to the detection and treatment of PH.

PROSPERO

CRD42017075423.

Hypertension in older adults in Africa: A systematic review and meta-analysis

BACKGROUND

Hypertension is the leading driver of cardiovascular disease deaths in Africa. Its prevalence is highest in older populations. Yet, this group has received little attention in many African countries. We conducted a systematic review and meta-analysis (PROSPERO registration: CRD42017056474) to estimate the prevalence of hypertension in older adults living in Africa.

METHODS

We searched grey literature and major electronic databases including PubMed and Embase for population-based studies and published between 1 January 1980 to 28 May 2018 reporting the prevalence of hypertension for adults aged ≥50 years living in Africa. We employed a random effects model to estimate the pooled prevalence across included studies.

FINDINGS

We screened 10,719 articles and retrieved 103 full-text articles to evaluate for inclusion in the review. Thirty-four unique studies providing 37 data points on 43,025 individuals in 15 African countries were analyzed. The prevalence of hypertension ranged from 22.3% to 90.0% from the individual studies while the overall pooled prevalence was 57.0% (95% CI 52%-61%). The prevalence was not statistically significantly different by sex, residence, or African sub-region. In individual studies, older age and overweight/obesity were independently associated with hypertension. Twenty-nine (78%) data points were deemed to be of low- or moderate-risk of bias. Eliminating high-risk bias studies made little difference to the pooled estimate of hypertension. Sensitivity analyses, omitting one study at a time, identified three studies with significant but relatively small impact on the pooled estimate. We observed substantial heterogeneity (I2 = 98.9%) across the studies which was further explored by meta-regression analyses. Overall, the GRADE assessment suggested moderate quality evidence in the results.

CONCLUSION

The persistent high prevalence of hypertension among older adults in Africa, even in rural populations warrants more attention to the cardiovascular health of this group by public health authorities.

Retinal imaging to identify target organ damage in older Africans: A pilot study

By 2030, sub-Saharan Africa is forecast to see the steepest rise in the number of people with hypertension of any world region. Hypertensive retinopathy is known to be a common complication of hypertension in developed countries and some studies suggest it is associated with the presence of other hypertension-related end-organ damage (EOD) such as stroke and cardiovascular disease. In Tanzania hypertension is relatively more common than in other parts of sub-Saharan Africa, especially in the older population; however, the prevalence of hypertensive retinopathy and its association with EOD remain unknown. The authors conducted a cross-sectional study of elderly, community-dwelling, rural Tanzanians to determine the prevalence of hypertensive retinopathy and its association with hypertension and other forms of EOD. Hypertensive retinopathy was diagnosed based on retinal imaging. In a cohort of 61 patients with gradable images, the authors found the overall prevalence of hypertensive retinopathy to be 64% (n = 39), which was strongly associated with hypertension (X² [1] = 4.207, P = .004), with a significant trend towards more severe retinopathy with more severe hypertension (r = .377, P = .003). The authors did not find hypertensive retinopathy to be associated with other forms of EOD. Hypertensive retinopathy is highly prevalent in this population and is associated in most but not all cases with hypertension. These findings do not suggest that it could be used as a screening tool for EOD, but it is important to identify and educate patients with retinopathy about possible complications of the condition.