Triggering of stroke by ambient temperature variation: a case-crossover study in Maputo, Mozambique.

OBJECTIVES: The effect of ambient temperature as a stroke trigger is likely to differ by type of stroke and to depend on non-transient exposures that influence the risk of this outcome. We aimed to quantify the association between ambient temperature variation and stroke, according to clinical characteristics of the events, and other risk factors for stroke. METHODS: We conducted a case-crossover study based on a 1-year registry of the hospital admissions due to newly occurring ischemic and hemorrhagic stroke events in Maputo, Mozambique's capital city (N=593). The case-period was defined as the 7 days before the stroke event, which was compared to two control periods (14-21 days and 21-28 days before the event). We computed humidity- and precipitation-adjusted odds ratios (OR) and 95% confidence intervals (95%CI) using conditional logistic regression. RESULTS: An association between minimum temperature declines higher than 2.4 °C in any two consecutive days in the previous week and the occurrence of stroke was observed only for first events (OR=1.43, 95%CI: 1.15-1.76). Stronger and statistically significant associations were observed for hemorrhagic stroke (OR=1.50, 95%CI: 1.07-2.09) and among subjects not exposed to risk factors, including smoking, high serum cholesterol or atrial fibrillation. No differences in the effect of temperature were found according to the patients' vital status 28 days after the event. CONCLUSIONS: First stroke events, especially of the hemorrhagic type, were triggered by declines in the minimum temperature between consecutive days of the preceding week.

The effect of season and temperature variation on hospital admissions for incident stroke events in Maputo, Mozambique.

BACKGROUND: Identifying locale-specific patterns regarding the variation in stroke incidence throughout the year and with atmospheric temperature may be useful to the organization of stroke care, especially in low-resource settings. GOAL: We aimed to describe the variation in the incidence of stroke hospitalizations across seasons and with short-term temperature variation, in Maputo, Mozambique. METHODS: Between August 1, 2005, and July 31, 2006, we identified 651 stroke events in Maputo dwellers, according to the World Health Organization's STEPwise approach. The day of symptom onset was defined as the index date. We computed crude and adjusted (humidity, precipitation and temperature) incidence rate ratios (IRRs) and 95% confidence intervals (CIs) with Poisson regression. RESULTS: Stroke incidence did not vary significantly with season (dry versus wet: crude IRR = .98, 95% CI: .84-1.15), atmospheric temperature at the index date, or average atmospheric temperature in the preceding 2 weeks. The incidence rates of stroke were approximately 30% higher when in the previous 10 days there was a decline in the minimum temperature greater than or equal to 3 °C between any 2 consecutive days (variation in minimum temperature -5.1 to -3.0 versus -2.3 to -.4, adjusted IRR = 1.31, 95% CI: 1.09-1.57). No significant associations were observed according to the variation in maximum temperatures. CONCLUSIONS: Sudden declines in the minimum temperatures were associated with a higher incidence of stroke hospitalizations in Maputo. This provides important information for prediction of periods of higher hospital affluence because of stroke and to understand the mechanisms underlying the triggering of a stroke event.

Low prevalence of hypertension with pharmacological treatments and associated factors.

OBJECTIVE: To assess the determinants of the lack of pharmacological treatment for hypertension. METHODS: In 2005, 3,323 Mozambicans aged 25-64 years old were evaluated. Blood pressure, weight, height and smoking status were assessed following the Stepwise Approach to Chronic Disease Risk Factor Surveillance. Hypertensives (systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg and/or antihypertensive drug therapy) were evaluated for awareness of their condition, pharmacological and non-pharmacological management, as well as use of herbal or traditional remedies. Prevalence ratios (PR) were calculated, adjusted for sociodemographic characteristics, cardiovascular risk factors and non-pharmacological treatment. RESULTS: Most of the hypertensive subjects (92.3%), and nearly half of those aware of their condition were not treated pharmacologically. Among the aware, the prevalence of untreated hypertension was higher in men {PR = 1.61; 95% confidence interval (95%CI 1.10;2.36)} and was lower in subjects under non-pharmacological treatment (PR = 0.58; 95%CI 0.42;0.79); there was no significant association with traditional treatments (PR = 0.75; 95%CI 0.44;1.26). CONCLUSIONS: The lack of pharmacological treatment for hypertension was more frequent in men, and was not influenced by the presence of other cardiovascular risk factors; it could not be explained by the use of alternative treatments as herbal/traditional medicines or non-pharmacological management. It is important to understand the reasons behind the lack of management of diagnosed hypertension and to implement appropriate corrective actions to reduce the gap in the access to healthcare between developed and developing countries.

Low prevalence of hypertension with pharmacological treatments and associated factors / Baixa prevalencia de hipertensao com tratamento farmacologico e fatores associados / Baja prevalencia de hipertension con tratamiento farmacologico y factores asociados

OBJECTIVE: To assess the determinants of the lack of pharmacological treatment for hypertension. METHODS: In 2005, 3,323 Mozambicans aged 25-64 years old were evaluated. Blood pressure, weight, height and smoking status were assessed following the Stepwise Approach to Chronic Disease Risk Factor Surveillance. Hypertensives (systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg and/or antihypertensive drug therapy) were evaluated for awareness of their condition, pharmacological and non-pharmacological management, as well as use of herbal or traditional remedies. Prevalence ratios (PR) were calculated, adjusted for sociodemographic characteristics, cardiovascular risk factors and non-pharmacological treatment. RESULTS: Most of the hypertensive subjects (92.3%), and nearly half of those aware of their condition were not treated pharmacologically. Among the aware, the prevalence of untreated hypertension was higher in men {PR = 1.61; 95% confidence interval (95%CI 1.10;2.36)} and was lower in subjects under non-pharmacological treatment (PR = 0.58; 95%CI 0.42;0.79); there was no significant association with traditional treatments (PR = 0.75; 95%CI 0.44;1.26). CONCLUSIONS: The lack of pharmacological treatment for hypertension was more frequent in men, and was not influenced by the presence of other cardiovascular risk factors; it could not be explained by the use of alternative treatments as herbal/traditional medicines or non-pharmacological management. It is important to understand the reasons behind the lack of management of diagnosed hypertension and to implement appropriate corrective actions to reduce the gap in the access to healthcare between developed and developing countries. .

OBJETIVO: Analisar os determinantes da falta de tratamento farmacológico da hipertensão. MÉTODOS: Foram avaliados 3.323 moçambicanos de 25 a 64 anos em 2005. A pressão arterial, peso, altura e tabagismo foram avaliados segundo o estudo Stepwise Approach to Chronic Disease Risk Factor Surveillance . Os hipertensos (pressão arterial sistólica ≥ 140 mmHg e/ou pressão arterial diastólica ≥ 90 mmHg e/ou terapia anti-hipertensiva) foram avaliados para verificar se eram conscientes de sua hipertensão, se recebiam tratamento farmacológico ou não farmacológico e se usavam ervas ou remédios tradicionais. Foram calculadas as razões de prevalência (PR) para hipertensão não tratada, ajustadas para características sociodemográficas, fatores de risco cardiovascular e tratamento não farmacológico. RESULTADOS: A maioria dos hipertensos (92,3%) e quase metade dos conscientes de sua hipertensão não eram tratados com fármacos. Entre os que sabiam ser hipertensos, a hipertensão sem tratamento era mais frequente em homens (PR = 1,61; IC95% 0,56;1,43) e não podia ser explicada pelo uso de tratamento não farmacológico (PR = 0,58; IC95% 0,42;0,79); não havia associação significativa com os tratamentos tradicionais (PR = 0,75; IC95% 0,44;1,26). CONCLUSÕES: A falta de tratamento farmacológico da hipertensão, mais frequente em homens, não se explica por outros fatores de risco cardiovascular, nem pelo uso de tratamentos tradicionais ou tratamento não farmacológico. É importante entender as razões da falta de tratamento da hipertensão diagnosticada e implementar medidas corretivas apropriadas, para reduzir as diferenças ...

OBJETIVO: Analizar los determinantes de la falta de tratamiento farmacológico de la hipertensión. METODOS: Se evaluaron 3.323 mozambicano de 25 a 64 años en 2005. La presión arterial, peso, altura y tabaquismo fueron evaluados según el estudio Stepwise Approach to Chronic Risk Factor Surveillance. Los hipertensos (presión arterial sistólica ≥ 140 mmHg y/o presión arterial diastólica 90 mmHg y/o terapia anti-hipertensiva) fueron evaluados para verificar si eran conscientes de su hipertensión, si recibían tratamiento farmacológico o no farmacológico, y si usaban hierbas o remedios tradicionales. Se calcularon los cocientes de prevalencia (PR) para hipertensión no tratada, ajustadas para características sociodemográficas, factores de riesgo cardiovascular y tratamiento no farmacológico. RESULTADOS: La mayoría de los hipertensos (92,3%) y casi la mitad de los conscientes de su hipertensión no eran tratadas con fármacos. Entre los que sabían ser hipertensos, la hipertensión sin tratamiento era más frecuente en hombres (PR =1,61; IC95% 0,56;1,43) y no podía ser explicada por el uso de tratamiento no farmacológico (PR= 0,58; IC95% 0,42;0,79); no había asociación significativa con los tratamientos tradicionales (PR= 0,75; IC95% 0,44;1,26). CONCLUSIONES: La falta de tratamiento farmacológico de la hipertensión, más frecuente en hombres, no se explica por otros factores de riesgo cardiovascular, ni por el uso de tratamientos tradicionales o tratamiento no farmacológico. Es importante entender las razones de la falta de tratamiento de la hipertensión diagnosticada e implementar medidas correctivas apropiadas, para reducir las diferencias en el acceso a ...

Determinants of early case-fatality among stroke patients in Maputo, Mozambique and impact of in-hospital complications.

The burden of stroke is increasing in developing countries that struggle to manage it efficiently. We identified determinants of early case-fatality among stroke patients in Maputo, Mozambique, to assess the impact of in-hospital complications. Patients admitted to any hospital in Maputo with a new stroke event were prospectively registered (n = 651) according to the World Health Organization's STEPwise approach, in 2005-2006. We assessed the determinants of in-hospital and 28-day fatality, independently of age, gender and education, and computed population attributable fractions. In-hospital mortality was higher among patients with Glasgow score at admission ≤ 6 (more than fivefold) or needing cardiopulmonary resuscitation during hospitalization (approximately 2.5-fold). Pneumonia and deep vein thrombosis/other cardiovascular complications during hospitalization were responsible for 19.6% (95% confidence interval, 5.3 to 31.7) of ischaemic stroke and 15.9% (95% confidence interval, 5.8 to 24.9) of haemorrhagic stroke deaths until the 28th day. Ischaemic stroke patients with systolic blood pressure 160-200 mmHg had lower in-hospital mortality (relative risk = 0.32, 95% confidence interval, 0.13 to 0.78), and, for those with haemorrhagic events (haemorrhagic stroke), 28-day mortality was higher when systolic blood pressure was over 200 mmHg (hazard ratio = 3.42; 95% confidence interval, 1.02 to 11.51), compared with systolic blood pressure 121-140 mmHg. Regarding diastolic blood pressure, the risk was lowest at 121-150 mmHg for ischaemic stroke and at 61-90 mmHg for haemorrhagic stroke. Early case-fatality was mostly influenced by stroke severity and in-hospital complications. The allocation of resources to the latter may have a large impact on the reduction of the burden of stroke in this setting.

Hypertension prevalence, awareness, treatment, and control in mozambique: urban/rural gap during epidemiological transition.

The prediction of cardiovascular risk profile trends in low-income countries and timely action to modulate their transitions are among the greatest global health challenges. In 2005 we evaluated a nationally representative sample of the Mozambican population (n=3323; 25 to 64 years old) following the Stepwise Approach to Chronic Disease Risk Factor Surveillance. Prevalence of hypertension (systolic blood pressure > or =140 mm Hg and/or diastolic blood pressure > or =90 mm Hg and/or antihypertensive drug therapy), awareness (having been informed of the hypertensive status by a health professional in the previous year), treatment among the aware (use of antihypertensive medication in the previous fortnight), and control among those treated (blood pressure <140/90 mm Hg) were 33.1% (women: 31.2%; men: 35.7%), 14.8% (women: 18.4%; men: 10.6%), 51.9% (women: 61.1%; men: 33.3%), and 39.9% (women: 42.9%; men: 28.7%), respectively. Urban/rural comparisons are presented as age- and education-adjusted odds ratios (ORs) and 95% CIs. Among women, hypertension (OR: 2.0; 95% CI: 1.2 to 3.0) and awareness (OR: 4.3; 95% CI: 1.9 to 9.5) were more frequent in urban areas. No urban/rural differences were observed in men (hypertension: OR: 1.3, 95% CI: 0.9 to 2.0; awareness: OR: 1.5, 95% CI: 0.5 to 4.7). Treatment prevalence was not significantly different across urban/rural settings (women: OR: 1.4, 95% CI: 0.5 to 4.4; men: OR: 0.3, 95% CI: 0.1 to 1.4). Control was less frequent in urban women (OR: 0.2; 95% CI: 0.0 to 1.0) and more frequent in urban men (OR: 78.1; 95% CI: 2.2 to 2716.6). Our results illustrate the changing paradigms of "diseases of affluence" and the dynamic character of epidemiological transition. The urban/rural differences across sexes support a trend toward smaller differences, emphasizing the need for strategies to improve prevention, correct diagnosis, and access to effective treatment.

Influence of two doses of irbesartan on non-dipper circadian blood pressure rhythm in salt-sensitive black hypertensives under high salt diet.

The authors examined whether the blockage of angiotensin II receptors by irbesartan (IRB) can reverse the "non-dipper" circadian rhythm of blood pressure (BP) to a "dipper" pattern in black salt-sensitive hypertensive patients submitted to a high-sodium loading. Twelve black salt-sensitive hypertensive patients (seven men; age, 35-58 years) on a high-sodium diet (300 mmol Na+ per day) were followed for 8 weeks. A placebo was given during the first 2 weeks, followed by 2 weeks on IRB 150 mg/d, 2 weeks on placebo, and 2 weeks on IRB 300 mg/d. On the last day of placebo, IRB 150 mg/d, and IRB 300 mg/d treatments, 24-hour BP and urinary 24-hour excretion of Na+ and potassium were measured. On placebo, ambulatory mean arterial pressure (MAP) was 112 mm Hg+/-2 (24 h), 112 mm Hg+/-2 (daytime), and 111 mm Hg+/-2 (nighttime), showing a clear circadian non-dipper profile. Versus placebo, IRB 150 mg/d reduced MAP by 4.2 mm Hg+/-1.1 (24 h), 2.6 mm Hg+/-0.8 (daytime) and 6.0 mm Hg+/-1.3 (nighttime; P<0.05 vs. placebo) and IRB 300 mg/d reduced MAP by 7.8 mm Hg+/-1.4 (24 h), 3.9 mm Hg+/-1.1 (daytime), and 11.8 mm Hg+/-2.1 mm Hg (all P<0.02 vs. placebo); nighttime/daytime MAP decrease was 0.7+/-0.8% on placebo, 3.5+/-2.1% on IRB 150 mg/d, and 7.0+/-1.2% on IRB 300 mg/d (P<0.02 for trend). Compared with placebo, IRB significantly increased serum potassium and plasma renin activity and reduced fractional excretion of potassium and plasma aldosterone levels in a dose-dependent manner. Body weight and urinary sodium excretion did not change throughout the study. It was concluded that the angiotensin receptor blocker IRB can reverse the BP non-dipper profile in salt-sensitive hypertensive patients on a high-salt diet, restoring nocturnal BP decline by a predominantly dose-dependent reduction of nighttime BP. Although the increment of potassium balance and reduction of aldosterone may account for this effect, it occurs independently of increased natriuresis. It is speculated that blunting of nighttime BP decrease in black salt-sensitive hypertensive patients may be related to a deficient suppression of the renin-angiotensin system during the night.

Evaluation of the antiurolithiatic activity of the extract of Costus spiralis Roscoe in rats.

The antiurolithiatic activity of the water extract of Costus spiralis Roscoe was tested on formation of calculi on implants of calcium oxalate crystals or zinc disc in the urinary bladder of rats. The plant is a species from the family Zingiberaceae used in Brazilian folk medicine in urinary affections and for expelling urinary stones. Implantation of the foreign body in the urinary bladder of adult rats induced formation of urinary stones and hypertrophy of the smooth musculature. Oral treatment with the extract of Costus spiralis Roscoe (0.25 and 0.5 g/kg per day) after 4 weeks surgery reduced the growth of calculi, but it did not prevent hypertrophy of the organ smooth musculature. The contractile responses of isolated urinary bladder preparations to the muscarinic agonist bethanecol, in the presence and absence of the extract (0.3-3 mg/ml) or atropine (0.3-3 nM) did not differ among the experimental groups. The results indicate that the extract of Costus spiralis Roscoe is endowed with antiurolithiatic activity confirming thus folk information. The effect, however, was unrelated to increased diuresis or to a change of the muscarinic receptor affinity of the bladder smooth musculature to cholinergic ligands.