Systematic Review of Hypertension and Diabetes Burden, Risk Factors, and Interventions for Prevention and Control in Malawi: The NCD BRITE Consortium.

Recent studies have found an increasing burden of noncommunicable diseases in sub-Saharan Africa. A compressive search of PubMed, Medline, EMBASE, and the World Health Organization Global Health Library databases was undertaken to identify studies reporting on the prevalence, risk factors, and interventions for hypertension and diabetes in Malawi. The findings from 23 included studies revealed a high burden of hypertension and diabetes in Malawi, with estimates ranging from 15.8% to 32.9% and from 2.4% to 5.6%, respectively. Associated risk factors included old age, tobacco smoking, excessive alcohol consumption, obesity, physical inactivity, high salt and sugar intake, low fruit and vegetable intake, high body mass index, and high waist-to-hip ratio. Certain antiretroviral therapy regimens were also associated with increased diabetes and hypertension risk in human immunodeficiency virus patient populations. Nationwide, the quality of clinical care was generally limited and demonstrated a need for innovative and targeted interventions to prevent, control, and treat noncommunicable diseases in Malawi.

Accessing clinical services and retention in care following screening for hypertension and diabetes among Malawian adults: an urban/rural comparison.

OBJECTIVE: Interventions to impact on the burden of chronic noncommunicable diseases, such as hypertension and diabetes, include screening of asymptomatic adults, but little is known about the subsequent course of clinical care. We report on the uptake of referral for clinical assessment and retention in care, following a large urban/rural population screening program in Malawi. METHODS: Adult residents were screened for raised blood pressure and raised fasting blood glucose at a demographic surveillance site in rural Karonga District and in urban Area 25, Lilongwe with well supported chronic care clinics. Successful uptake was defined as presenting for clinical assessment within 6 weeks of referral, and nonattenders were followed at home. Logistic regression was used to examine association of uptake with demographic and clinical factors. Retention was assessed using survival analysis techniques. RESULTS: A total of 27 305 participants were screened for hypertension and diabetes between May 2013 and September 2015. Of these, 4075 (14.9%) were referred for suspected hypertension (3640), diabetes (172), or both (263). Among those referred, 2480 (60.9%), reported for clinical assessment. Factors associated with uptake of care included being female, rural residency, older age, unemployment, prior medication, and diabetes. Retention, for those enrolled in care following a formal clinical assessment, was associated with the final diagnosis following clinical assessment, rural residency, and older age. CONCLUSION: Screening for hypertension and diabetes identifies large numbers of individuals who need further clinical assessment, but strategies are needed to ensure better linkage and retention into care.

Non-communicable diseases in sub-Saharan Africa: understanding the drivers of the epidemic to inform intervention strategies.

Sub-Saharan Africa is experiencing a rapidly increasing epidemic of non-communicable diseases (NCDs), while it continues to face longstanding challenges from infectious diseases. This double burden of disease could have a devastating impact on a continent that already has significant resource constraints, emphasizing the urgent need for appropriate interventions in the region. However, it is crucial to have a careful understanding of the local drivers of NCDs. This should not only include study of the traditional lifestyle risk factors, but also an examination of emerging risk factors (such as the influence of insults early in life or interactions with infection), which may be of particular importance in Africa.

Noncommunicable Lung Disease in Sub-Saharan Africa. A Community-based Cross-Sectional Study of Adults in Urban Malawi.

RATIONALE: Noncommunicable diseases are major causes of morbidity and mortality in sub-Saharan Africa (sSA). Valid burden of disease estimates are lacking for noncommunicable lung disease in sSA. OBJECTIVES: We performed a community-based survey to determine the prevalence of chronic lung disease among adults 18 years or older in Malawi, using American Thoracic Society standard spirometry, internationally validated respiratory symptom and exposure questionnaires, and an assessment of HIV status. METHODS: An age- and sex-stratified random sample of 2,000 adults was taken from the population of the Chilomoni district of Blantyre, Malawi. Fieldworkers collected questionnaire data, conducted HIV testing, and performed pre- and post-bronchodilator spirometry on eligible participants. Survey-weighted population prevalence estimates of respiratory symptoms and spirometric abnormalities were computed, and bivariate and multivariable regression were used to identify associated variables. MEASUREMENTS AND MAIN RESULTS: Questionnaire data, HIV status, and standard spirometry were obtained from 1,059, 933, and 749 participants, respectively. Current respiratory symptoms, exposure to biomass, and ever-smoking were reported by 11.8, 85.2, and 10.4% of participants, respectively. HIV prevalence was 24.2%. Moderate to severe airway obstruction was seen in 3.6%. The prevalence of spirometric restriction was 38.6% using National Health and Nutrition Examination Survey III reference ranges and 9.0% using local reference ranges. Age was positively associated with obstruction, whereas low body mass index was associated with restriction. CONCLUSIONS: More than 40% of the Malawian adults in our urban population sample had abnormal lung function (mostly restrictive) in the context of widespread exposure to biomass smoke and a high prevalence of HIV. These findings potentially have major public health implications for Malawi and the broader sSA region.

Metabolic pathways promoting intrahepatic fatty acid accumulation in methionine and choline deficiency: implications for the pathogenesis of steatohepatitis.

The pathological mechanisms that distinguish simple steatosis from steatohepatitis (or NASH, with consequent risk of cirrhosis and hepatocellular cancer) remain incompletely defined. Whereas both a methionine- and choline-deficient diet (MCDD) and a choline-deficient diet (CDD) lead to hepatic triglyceride accumulation, MCDD alone is associated with hepatic insulin resistance and inflammation (steatohepatitis). We used metabolic tracer techniques, including stable isotope ([¹³C4]palmitate) dilution and mass isotopomer distribution analysis (MIDA) of [¹³C2]acetate, to define differences in intrahepatic fatty acid metabolism that could explain the contrasting effect of MCDD and CDD on NASH in C57Bl6 mice. Compared with control-supplemented (CS) diet, liver triglyceride pool sizes were similarly elevated in CDD and MCDD groups (24.37 ± 2.4, 45.94 ± 3.9, and 43.30 ± 3.5 µmol/liver for CS, CDD, and MCDD, respectively), but intrahepatic neutrophil infiltration and plasma alanine aminotransferase (31 ± 3, 48 ± 4, 231 ± 79 U/l, P < 0.05) were elevated only in MCDD mice. However, despite loss of peripheral fat in MCDD mice, neither the rate of appearance of palmitate (27.2 ± 3.5, 26.3 ± 2.3, and 28.3 ± 3.5 µmol·kg⁻¹·min⁻¹) nor the contribution of circulating fatty acids to the liver triglyceride pool differed between groups. Unlike CDD, MCDD had a defect in hepatic triglyceride export that was confirmed using intravenous tyloxapol (142 ± 21, 122 ± 15, and 80 ± 7 mg·kg⁻¹·h⁻¹, P < 0.05). Moreover, hepatic de novo lipogenesis was significantly elevated in the MCDD group only (1.4 ± 0.3, 2.3 ± 0.4, and 3.4 ± 0.4 µmol/day, P < 0.01). These findings suggest that important alterations in hepatic fatty acid metabolism may promote the development of steatohepatitis. Similar mechanisms may predispose to hepatocyte damage in human NASH.

Prenatal glucocorticoid exposure and physiological programming of adult disease.

Compelling epidemiological evidence suggests that the early environment is an important determinant of later risk of disease. In particular, low birth weight has been associated with an increased risk of cardiovascular and metabolic disorders, including hypertension, Type 2 diabetes mellitus and ischemic heart disease, independent of classical adult lifestyle risk factors such as smoking, adult weight, social class, excess alcohol intake and sedentary lifestyle. These observations have led to a revolutionary concept of early life physiological programming. The molecular mechanisms that underlie this relationship remain unclear, but one major hypothesis implicates fetal overexposure to glucocorticoid stress hormones. This article will review evidence for this hypothesis.

Thyroid disease and increased cardiovascular risk.

The effects of thyroid dysfunction are thought to be reversible on restoration of euthyroidism, but postmortem and epidemiologic data suggest that subclinical or treated thyroid disease is associated with increased vascular risk. In order to determine the extent of this risk, and to explore whether the nature and/or treatment of thyroid disease are critical in this relationship, we used medical record linkage to match patients with treated thyroid disease of various etiologies with routinely collected national inpatient and daycase hospital discharge records and death records, and assessed the number of hospitalizations from cardiovascular or cerebrovascular disease or death in patients with thyroid disease and control patients. Patients treated for Graves' disease had more hospitalizations from cardiovascular disease than controls (relative risk, 1.42; 95% confidence interval, 1.20 to 1.67; p < 0.001). Toxic multinodular goiter was also associated with significantly higher rates of cardiovascular disease (relative risk, 1.50; 95% confidence interval, 1.11 to 2.02; p = 0.008). Patients with Hashimoto's thyroiditis aged over 50 years had a threefold increase in cardiovascular admissions compared to controls (23.5% and 6.5%, respectively; 95% confidence interval for difference, 6.0% to 27.9%; p = 0.003). Thus, different forms of thyroid disease were associated with increased long-term vascular risk despite restoration of euthyroidism. The mechanisms that mediate this risk are unclear but may not involve thyroid hormone abnormality.