Cracking the whip on childhood mortality--role of the specialized neonatal unit in Eritrea.

UNLABELLED: Health care services in developing countries are being challenged by high childhood mortality rates. Although there have been tremendous strides made in reducing infant mortality rates largely due to vaccinations and improved standards of living, a lot remains to be done to reduce neonatal mortality. Achievement of the Millennium Development Goal (MDG) number 4 on childhood mortality will remain unattainable in most developing countries unless purpose based interventions targeted at reducing neonatal mortality are instituted. This viewpoint is based on the experiences gained in Eritrea, a country that gained independence less than twenty years ago following a protracted war that left a trail of destruction of infrastructure in general and health facilities in particular. War that broke out with Ethiopia less than 10 years into its independence and border conflicts followed by a no peace no war stalemate situation aggravated by frequent droughts have continued to throttle economic recovery, reconstruction and rehabilitative efforts. The population is estimated at 3.5 million comprising of nine ethnic groups who speak different languages. The country has a surface area of 124,000 km2 which shares borders with Sudan, Ethiopia, Djibouti and the Red Sea. CONCLUSION: Attainment of the MDG number 4 on reduction of childhood mortality can be achieved by addressing morbidities of the neonate where the bottle neck currently appears to be sited.

Continuing communicable disease burden in Eritrea.

BACKGROUND AND METHODS: A retrospective study of the national health profile of Eritreans, focusing on acute respiratory tract infection (ARTI), tuberculosis (TB), diarrhoea, sexually transmitted diseases (STDs) and HIV/AIDS, was done on data from 1998 to 2003 through a health information management system. Records were included for patients of all ages receiving outpatient and inpatient hospital services during the study period. All incidence rates were given as cases per 100,000 population. RESULTS: The incidence of ARTI increased from 6,500 cases per annum in 1998 to 8 500 in 2003, representing a 30% increase. Diarrhoea rates remained unchanged, averaging 3,000 cases. For both ARTI and diarrhoea, rates were at least 3 times higher in children under 5 years of age than in those over 5 years of age. The incidences of TB and STDs decreased from 370 and 220 in 1998 to 170 and 80 in 2003, respectively. HIV/AIDS incidence increased from 40 in 1998 to 65 in 2003, reflecting a 60% increase. The case fatality rates (CFRs) for HIV/AIDS and TB were 12% and 2% in 1998, increasing to 14% and 3%, respectively, in 2001. The CFR for ARTI and diarrhea remained low at 0.3%. CFRs were higher in children under 5 years than in those over 5 years for all the diseases but rates declined consistently, probably reflecting the positive impact of the introduction of the integrated management of childhood illness (IMCI). Although the incidence rate of HIV/AIDS was relatively low compared with rates for TB, ARTI and diarrhoea, the HIV/AIDS CFR was relatively high, posing a threat to the gains made in control of infectious diseases. The disease burden from TB and STDs declined over the 6-year study period, while that from ARTI and HIV/AIDS increased. Consequently the overall disease burden from communicable diseases remained unchanged over the study period.

The prevalence of hypertension and its relationship with obesity: results from a national blood pressure survey in Eritrea.

The prevalence of cardiovascular diseases has been shown to be on the increase in Africa based on hospital-based information and limited national surveys. A recent report on analysis of data from Health Information Management Systems (HIMS) highlighted an increasing burden of noncommunicable diseases (NCDs) in Eritrea, with the incidence of hypertension doubling in a space of 6 years. HMIS data are only a proxy of national prevalence rates, necessitating the conduct of national surveys. The WHO STEPwise approach to surveillance of NCDs was used for the national NCD risk factor survey in 2004. This report focuses on blood pressure (BP) and obesity (body mass index (BMI) > 30 kg/m2) as NCD risk factors in Eritrea. A total of 2352 people in age groups 15 to 64 years participated in the survey. The prevalence of hypertension defined as BP > 140/90 mmHg was 15.9% in the general population, with 16.4% in urban and 14.5% in rural areas, 17% of whom were males while 15% were females. BMI was positively associated with systolic (SBP), diastolic and mean arterial pressure. Although the prevalence of obesity (3.3%) was higher in females, the effect of BMI on BP was higher in males than in females (regression coefficient 0.64 and 0.38, respectively, P < or = 0.05), especially in those >45 years. BMI did not have a significant effect on BP in lean people (BMI < 19) and in those with high BMI, but was positively correlated to SBP in those with normal BMI (P < or = 0.02). BMI and age appear to play a synergistic role in creating a strong association with BP.

Recurrent cholera epidemics in Kano--northern Nigeria.

OBJECTIVES: The study examined the factors associated with recurrent cholera epidemics in Kano State of Northern Nigeria, the management of the epidemics and health outcomes. METHODS: Using epidemiological data from the Public Health Department of the Kano State Ministry of Health, the study examined the frequency and geographical distribution of the epidemics for the period 1995 to 2001; procedures for detection; control measures as well as results of biological and bacteriological testing of water from different sources. Mapping and testing for significance of faecal contamination of water sources were done. RESULTS: The number of cholera cases in the city was 2 630; 847 and 2 347 in 1995/6, 1997 and 1999 respectively. The State Epidemiological Unit which is responsible for surveillance detected epidemics using set thresholds and activated multi-sectoral emergency responses. Control measures encompassed accurate diagnosis at the reference laboratory, Kaduna; registration of cases; case management and public health measures targeting personal hygiene and water treatment. The cholera epidemics attracted worldwide attention with emergency responses from many agencies including WHO, UNICEF and Medicens Sand Frontiers (MSF). Case fatality rates decreased from 15% in 1995/6 to 5% in 1997 and 2% in 1999. The organism responsible for all the outbreaks was Vibrio cholerae, el-tor of inaba serotype. Water contamination of all sources was the principal cause of the epidemics. There were statistically significant differences in levels of faecal contamination of water sources, wells being most affected, followed by piped water, chi2 = 11.556, (p < 0.02). Bore holes were relatively safer sources of water. Point source epidemics always started from Kano City before fanning out to the rest of the State. CONCLUSION: Multi-sectoral Epidemic Preparedness and Response (EPR) approaches have contributed to the reduction in case fatality rates over the years and should be sustained. However, in order to prevent future cholera epidemics, there is need to introduce intervention measures that address the root problems of poor sanitation and unsafe water supplies.

Microalbuminuria in urban Zimbabwean women.

The prevalence of microalbuminuria (MAU) in African populations has not been reported, nor has the relationship between MAU and hypertension been reported for these populations. We collected spot urine samples from 370 women, 25 years and older as a part of a population-based, cross-sectional blood pressure survey in an urban community in Zimbabwe and analysed the samples for albumin and beta2-microglobulin. The age-adjusted prevalence of hypertension was 30% for women 25 years and older in this community. After excluding the samples with hematuria (11%), the prevalence of MAU (3.0 < or = albumin-to-creatinine ratio (ACR, mg/mmol) <25.0) in the study population was 9%. When age-adjusted to the population in the community, the prevalence was 8% among women 25 years and older. The prevalence of MAU was substantially higher in hypertensive (HT) than in normotensive (NT) women (16% vs 4%, P<0.001). A significantly higher level of log ACR in HT was found in each age group except the youngest age group (age 25-34). In age-adjusted multiple regression, percent fat mass was negatively associated with log ACR (beta = -1. 18, 95% CI (-0.23, -2.21), P = 0.02). In a similar regression analysis, higher log beta8-microglobulin-to-creatinine ratio was very strongly associated with higher log ACR (beta = 0.34, 95% CI (0.25, 0.43), P<0.0001) and significantly associated with lower percent fat mass (beta = -1.02, 95% CI (-0.25, -1.8), P = 0.01). These results suggest that MAU is frequently caused by hypertension, but that other diseases may contribute to its presence.

Economic development and women's blood pressure: field evidence from rural Mashonaland, Zimbabwe.

A survey of 515 non-pregnant women at 12 geographically chosen research sites in rural Mashonaland shows significant differences in mean blood pressure, controlled by age cohorts. Three levels of economic development are identified: (1) the traditional economy on communal lands, with lowest blood pressure, (2) the wage economy in areas of large-scale commercial agriculture, with elevated blood pressure and (3) the wage economy in mining areas, with the highest elevation of blood pressure. The area is dominated by the primate city, Harare, up to distances of 300 km and beyond, from which forces of change and modernization emanate. It is seen that potassium, sodium and the sodium potassium ratio, are distance-related to Harare and that women's blood pressures tend to follow suit. The rise of body sodium in young persons at risk, often accompanied by declining potassium intake and other changes of modernization, suggest that more attention should be focused on rural areas in Africa, now in the throes of economic change.

Correlates of blood pressure in an urban Zimbabwean population and comparison to other populations of African origin.

We have evaluated the relationship between systolic blood pressure (SBP) and age, body mass index (BMI), waist circumference, sodium to potassium ratio (Na/K), and tobacco use in an urban African population. We conducted a random, population-based, cross-sectional survey of people 25 years and older in Marondera, Zimbabwe, with over-sampling in older age groups (n = 775), using a method comparable to that used in International Collaborative Study on Hypertension in Blacks (ICSHIB). The age-adjusted prevalences of hypertension in Marondera (SBP >/=140/DBP >/=90/antihypertensive medication) were 30% for women and 21% for men. The average BMI was 26.3 kg/m2 for women and 21.4 kg/m2 for men. The prevalence of hypertension had a steep association with age and in women ranged from 15% (25-34 years) to 63% (55 years and over) and in men from 9% to 47%. No tobacco use in women and greater Na/K ratio in spot urines in men were significantly associated with an increased SBP. In both men and women the levels of hypertension and SBP were strongly positively associated with BMI, although the relationship appeared to plateau in women with a BMI greater than >/=25 kg/m2. At a given BMI, men and women had similar SBPs and prevalences of hypertension. There is a very high prevalence of hypertension among urban Zimbabweans, particularly among women. Under the assumption the studies are comparable, the prevalence of hypertension in Zimbabwean women (41%) and men (26%) after age adjustment to the ICSHIB populations, appeared higher than almost all of the ICSHIB populations, including those with higher average body mass indexes. Journal of Human Hypertension (2000) 14, 65-73.

Lung function of Zimbabwean farm workers exposed to flue curing and stacking of tobacco leaves.

OBJECTIVES: To perform lung function tests on tobacco farm workers (TFWs) chronically exposed to flue curing and stacking of tobacco leaves and to compare them with vegetable farm workers (VFWs) who were not exposed to any known air pollutant (control). DESIGN: Comparative study. SETTING: Tobacco and vegetable farms. SUBJECTS: 20 TFWs and 30 VFWs. All subjects were male and the mean age, height and weight of the two groups were not significantly different. OUTCOME MEASURES: Lung function indices. RESULTS: Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and peak expiratory flow rate (PEFR) of the TFWs were 3.28 +/- 0.51 litres, 2.68 +/- 0.74 litres and 6.41 +/- 2.08 litres/second, respectively. These figures were significantly lower than 3.97 +/- 0.83 litres, 3.09 +/- 0.71 litres and 8.62 +/- 2.74 litres/second, respectively, for the control subjects (P < 0.01, 0.05 and 0.01, respectively). However, mean FEV1 as a percentage of the FVC (FEV1%) of the TFWs was not significantly different from that of the controls FVC of the TFWs declined with duration of service (r = 0.74; P < 0.01). CONCLUSION: The results are indicative of restrictive lung defect in the TFWs and may be attributed to long-term exposure to flue curing and stacking of tobacco leaves. The results also suggest the importance of the duration of exposure in the aetiology of lung impairment in this environment.

Effect of variation in environmental temperature on blood pressure: is it important?

OBJECTIVES: To study the effect of variation in environmental temperature on blood pressure and pulse. DESIGN: Repeated blood pressure and pulse measurements in volunteers on two days when environmental temperatures differed by 10 degrees C. SETTING: Part of an ongoing community based study. SUBJECTS: 25 Black subjects (23 males and two females) volunteered from a population cohort participating in an ongoing longitudinal study examining cardiovascular risk factors in an urban African Black environment. MAIN OUTCOME MEASURE: Mean systolic and diastolic blood pressures and pulse rates. RESULTS: The systolic and diastolic blood pressures were significantly higher when recorded at 15 degrees C than at 25 degrees C, mean difference 32.2 +/- 4.2, p < 0.001 and 19.5 +/- 3.0 p < 0.001) for systolic and diastolic blood pressures respectively. The pulse rate per minute at 15 degrees C was significantly lower than at 25 degrees C (mean difference 11.1 +/- 3.2 p = 0.002). CONCLUSIONS: A decrease in environmental temperature by 10 degrees C appears to increase blood pressure. Awareness of this phenomenon is important, especially when surprisingly high blood pressures are observed during low ambient temperatures, to avoid over diagnosis of hypertension. This phenomenon, together with that already established of the white coat hypertension, may lead to the erroneous diagnosis of hypertension.

Salt sensitivity is not associated with hyperinsulinaemia in a sample of rural black Zimbabweans.

OBJECTIVES: To investigate the relationship between salt sensitivity and hyperinsulinaemia in rural black African subjects. DESIGN: An intervention study where 27 subjects were divided into two groups; group 1 was initially salt loaded (300 mmol Na+/day), while group 2 was salt restricted (25 mmol Na+/day), each for 4 days, after which a cross-over study was done. SETTING: Chidamoyo, a rural area 383 km north of Harare, Zimbabwe. SUBJECTS: Twenty-seven rural volunteers (16 women, 11 men). OUTCOME MEASURES: Systolic and diastolic blood pressures, salt sensitivity, insulin and glucose levels, body mass index and mean arterial pressure. RESULTS: Mean arterial pressure, which was 91 +/- 2 mmHg on a low-salt diet, increased significantly (P < 0.01) to 105 +/- 3 mmHg on high-salt diet in the salt-sensitive subjects. In the same salt-sensitive subjects, the fasting insulin level was 8.4 +/- 0.8 microU/ml on a low-salt and 6.1 +/- 1.0 microU/ml on a high-salt diet. The difference was not statistically significant. CONCLUSIONS: Although salt pressor sensitivity was demonstrated in the subjects, there was no accompanying increase but rather a decrease in fasting insulin levels, suggesting that in the short term, salt sensitivity and hyperinsulinaemia are not linked in raising blood pressure in this sample of rural Zimbabwean subjects.

Relationship between blood pressure and body mass index in lean populations.

Associations between body mass index (BMI) and blood pressure (BP) have been consistently observed, but remain poorly understood. One unresolved question is whether there is a linear relationship across the entire BMI range. We investigated this question among 11,235 adult men and women from seven low-BMI populations in Africa and the Caribbean. We used kernel smoothing and multivariate linear and spline regression modeling to examine gender differences in the relationship and to test for a threshold. Age-adjusted slopes of BP on BMI were uniformly higher in men than women, with pooled slope ratios of 2.00 and 2.20 for systolic and diastolic BPs, respectively. Men displayed no evidence of age modification or nonlinearity in the relationship, and the age-adjusted slope of systolic BP on BMI was 0.90 (95% confidence interval [CI], 0.76 to 1.04). Women demonstrated both age modification and nonlinearity. For both younger (<45 years) and older (45+ years) women, the optimal change point for a single threshold model was found to be 21 kg/m2. Slopes of systolic BP on BMI above this threshold were positive and significant: 0.68 (95% CI, 0.54 to 0.81) and 0.53 (95% CI, 0.29 to 0.76) for younger and older women, respectively. Slopes below the threshold were essentially zero for both groups of women, and the difference between the slopes above and below the threshold was significant for younger women (P=.019). In summary, we observed a threshold at 21 kg/m2 in the relationship between BMI and BP for women but not for men. This contributes to the effort to identify the mechanisms that underlie this relationship and how they differ by gender.

Evaluation of an electronic blood pressure device for epidemiological studies.

An objective method for measuring blood pressure would enhance the usefulness of comparative survey research in hypertension. Previous studies have demonstrated that inexpensive, commercially available machines can achieve satisfactory levels of precision. We evaluated one such device in three field settings. Among 64 untreated hypertensive patients, electronic readings both in the clinic and at home were well correlated with 24 h ambulatory readings (correlation ranged from 0.6 to 0.8), consistently better than measurements obtained by human observers. Evaluation as part of a quality control exercise in an ongoing random population surveys from four countries demonstrated average correlations of 0.92 for systolic and 0.85 for diastolic between human and electronic readings. Subsequent use in survey research involving 4000 individuals in three African communities demonstrated consistency of the electronic devices. These cross-sectional surveys, in which measurements were made by non-professionals, provided qualitative estimates of rural-urban variation in blood pressure, demonstrating the practical utility of the technique. If verified by other evaluative studies, the new generation of semi-automatic electronci blood pressure devices could markedly enhance the comparability of hypertension prevalence studies.

Comparison of the Omron HEM-713C automated blood pressure monitor with a standard ausculatory method using a mercury manometer.

OBJECTIVES: To compare the Omron HEM-713C automated blood pressure machine with the standard ausculatory method using a mercury manometer. DESIGN: Blood pressures of randomly selected subjects were measured using both the Omron HEM-713C and the mercury manometer. SETTING: Dombotombo surburb in Marondera, Zimbabwe. SUBJECTS: One hundred and sixteen subjects 25 years and above (47 males and 69 females) randomly selected in Marondera. MAIN OUTCOME MEASURE: Systolic blood pressure and diastolic blood pressure. RESULTS: The Omron HEM-713C passed with a grade B for both systolic and diastolic blood pressures when using the British Hypertension Society protocol. It also passed both systolic and diastolic criteria for Association of the Advancement of Medical Instrumentation. CONCLUSION: The Omron HEM-713C compares well with the standard mercury manometer, we therefore recommend its use in both research and clinical applications which require blood pressure measurements.

Ethnic differences of renin-sodium profile and renal prostaglandins in the pathogenesis of systemic arterial hypertension.

OBJECTIVE: To compare renin-sodium profile and renal prostaglandins (PGs) of Black normotensive and hypertensive patients, with the same parameters of Caucasian normotensives and hypertensives, e.g. to reveal some of the ethnic differences in the pathogenesis of systemic (essential) hypertension. SUBJECTS: 27 Black Zimbabwean normotensive and 27 hypertensive patients were matched by age, sex and number to Caucasian normotensives and hypertensives (systolic blood pressure > 160 mm Hg or diastolic blood pressure > 95 mm Hg, or both). All were examined during two protocols producing sodium depletion (less than 40 mmol sodium diet/day) for five days, followed by sodium loading (300 mmol sodium diet/day) for another five days. Changes in plasma renin activity (PRA), urinary aldosterone (Aldo), prostaglandin E2(PGE2) and prostaglandin F2 alpha (PGF2 alpha) excretions were simultaneously assessed by radioimmunoassay. RESULTS: Compared to caucasians the Blacks showed similar basal aldosterone and Na+ excretion but significant Na+ retention (30pc) during Na+ loading. Their basal PRA was lower (32pc) and poorly responding to sodium depletion/loading. They had suppressed PG synthesis, the PGE2/PGF2 ratio being significantly decreased 11pc. Renin profiles, obtained by plotting PRA against urinary Na+ excretion showed prevalence of low renin hypertension (62pc) in Black patients. All Caucasian patients had normal renin hypertension. At basal level the Black hypertensives had suppressed synthesis of vasodilator PGF2/PGF2 alpha ratio by 32pc. This finding was in accordance with their low renin hypertension. During sodium depletion the PGs excretion was increased in both hypertensive groups. The opposite effect was found during sodium loading. CONCLUSION: This study shows ethnic differences in renin-sodium profile and renal PG synthesis, during changes in dietary sodium. It addresses an old medical controversy about the usefulness of renin profiling in identifying hypertensive patients who are at increased risk for heart attack (Whites with normal/high renin hypertension) or increased risk of stroke (Blacks with low renin, sodium mediated hypertension).

Prevalence of hypertension among women in rural Zimbabwe: a comparison of pregnant and non-pregnant women.

OBJECTIVES: To determine the prevalence of pregnancy induced hypertension (PIH) in rural Zimbabwe. DESIGNS: A blood pressure survey conducted in three socio-economic strata of rural Zimbabwe, communal lands, commercial farms and mining areas. SETTING: Rural Zimbabwe, Mashonaland West Province. SUBJECTS: 627 pregnant (> 20 weeks gestation) and 483 non pregnant (ages 16 to 45) women. MAIN OUTCOME MEASURE: Prevalence of PIH. RESULTS: PIH was defined in two ways: 1. A combination of > or = 2+ proteinuria and systolic and/or diastolic pressure > or = SD above the mean for all pregnant women (> or = 123/75 mmHg). 2. > or = 1+ proteinuria and blood pressure of 140 and/or 90 mmHg. Eight women met definition 1 and seven met definition 2, giving a prevalence of 0.8pc; 1.3pc and 3.2pc in communal lands, commercial farms and mines respectively. In non-pregnant women the prevalence of hypertension (> or = 160 and/or 95 mmHg) was 3.5pc; 5.4pc and 15.1pc in communal lands, commercial farms and mines respectively. CONCLUSION: PIH is rare in rural Zimbabwe. Hypertension among non-pregnant women of child bearing age is most common in mining communities which have many similarities to urban environments.

Renin-sodium profile and renal prostaglandins in the pathogenesis of systemic arterial hypertension in blacks.

Thirteen black women with systemic (essential) arterial hypertension, age-matched with normotensives, were examined during two protocols inducing sodium depletion and sodium loading respectively. Changes in plasma renin activity (PRA), urinary aldosterone values and prostaglandin E2 (PGE2) and F2a (PGF2a) excretion were simultaneously assessed. Renin profiles, obtained by the plotting of PRA against the urinary excretion of sodium, showed a 62% prevalence of low-renin hypertension, the remaining 38% of the patients having normal-renin hypertension. At basal level the hypertensives had suppressed renal synthesis of vasodilator PGE2 and a non-significant increase in venopressor PGF2a. This was reflected in the significant 32% decrease in the PGE2/PGF2a ratio. This finding was in keeping with their low-renin hypertension. During sodium depletion PG excretion was increased in both normotensive and hypertensive groups. The opposite effect was found during sodium loading. The results of this study do not support a natriuretic role for renal PGE2, but do support the hypothesis that there is decreased renal vasodepressor PGE2 synthesis in black hypertensive patients.

Aspects of insulin resistance in urbanisation-related hypertension in Zimbabwe: a preliminary report.

Insulin resistance has been associated with essential hypertension, obesity and old age. Likewise high blood pressure has been observed to develop in some rural people who migrate to urban areas in developing countries like Zimbabwe. The pathogenesis of this urbanisation-related hypertension is still unknown. We therefore investigated aspects of insulin resistance in urbanisation-related hypertension in Zimbabwean blacks using oral glucose tolerance tests. Thirty normotensive subjects and 30 newly diagnosed hypertensive patients participated in this study. All subjects had blood pressures measured by random zero sphygmomanometry. Fasting blood samples were taken before a 75 g oral glucose load was given. Four other blood samples were subsequently collected at 30 minute intervals and determination of blood glucose and insulin levels was made. Fasting glucose (mmol/l) and fasting insulin (in microU/ml) levels were, respectively, 4.8 +/- 0.2 and 19 +/- 2 in hypertensive patients which were significantly higher than 4.0 +/- 0.2 and 13 +/- 1.6 in normotensive patients (P < 0.05). In addition the area under the insulin curve was significantly higher in hypertensive than in normotensive patients (P < 0.05). These findings suggest that insulin resistance may play a role in urbanisation-related hypertension.

Factor VII, antithrombin III, leukocyte and platelet counts in a sample of black and white Zimbabwean blood donors.

Studies in Southern Africa have shown that whites have significantly greater morbidity and mortality from coronary heart disease than blacks. This study investigated the distribution of some haemostatic variables known or suspected to be correlated with greater risk for coronary heart disease in healthy black and white Zimbabwean men. Factor VII, antithrombin III, leukocyte and platelet counts were measured in 56 blacks and 29 whites aged between 20 and 50 years. We found significantly greater factor VII and leukocyte counts in the whites compared to the blacks. The other variables measured were similar in the two ethnic groups. These results suggest that the greater prevalence of coronary heart disease in whites is consistent with high levels of factor VII and white blood cell counts previously identified as risk factors for this condition.