The prevalence ofpsychiatric disorders at a primary care clinic in Soweto, Johannesburg

A pilot study to assess the prevalence of psychiatric disorders in a primary care clinic in Soweto was carried out at the Zola Community Health Centre in May 1991. Interviews were carried out by trained primary care clinic staff. The findings were reviewed and analysed by the authors. The prevalence of psychiatric disorders was found to be 14,38%. Methodological problems are listed and the results are discussed

An evaluation of late attenders in labour in Alexandra

To study why women present in late labour we interviewed 70 parturients in our labour worn for a period of 8 days in March 1990

Platelet and erythrocyte Mg²⁺, Ca²⁺, Na⁺, K⁺ and cell membrane adenosine triphosphatase activity in essential hypertension in blacks

<p>Objective: To assess the relationship between intracellular Mg2+, Ca2+, Na+ and K+ and cell membrane adenosine triphosphatase (ATPase) activity in normotensive and hypertensive blacks.</p> <p>Design: Intracellular cations and cell membrane ATPase activity were studied in black patients with untreated essential hypertension and age-, weight- and height-matched normotensive controls. Platelet, erythrocyte and serum Mg2+, Ca2+, Na+ and K+ levels as well as platelet and erythrocyte membrane Na+, K+ -ATPase, Ca2+ -ATPase and Mg2+-ATPase activities were measured in all subjects.</p> <p>Methods: Intracellular Na+ and K+ were measured by flame photometry and Mg+ and Ca+ by atomic absorption spectrophotometry. Cell membrane ATPase activity was determined by a colorimetric method.</p> <p>Results: The hypertensive group consistently demonstrated depressed activity of each ATPase studied, with significantly lower serum Mg2+, serum K+, erythrocyte Mg2+ and platelet Mg2+ levels compared with the normotensive group. Platelet Na+ and Ca2+ and erythrocyte Ca2+ were significantly elevated in the hypertensive group. In the hypertensive group, mean arterial pressure (MAP) was inversely correlated with platelet and erythrocyte membrane Na+, K+ -ATPase, Ca2+-ATPase and Mg2+-ATPase. Serum Mg2+, serum Ca2+ and platelet Mg2+ were negatively correlated with MAP in the hypertensive group whilst erythrocyte and platelet Ca2+ were positively correlated. In the normotensive group, platelet Mg2 + and MAP were negatively, and erythrocyte Ca2+ and MAP, positively correlated.</p> <p>Conclusions: Black patients with essential hypertension have widespread depression of cell membrane Na+, K+ -ATPase, Ca2+-ATPase and Mg2+-ATPase activities with serum and intracellular Mg2+ depletion and cytosolic Na+ and Ca2+ overload, which may reflect an underlying membrane abnormality in essential hypertension. These cellular abnormalities may be related to the defective transport mechanisms that in turn may be aggravated by Mg2+ depletion.</p&gt

Twenty-four hour ambulatory blood pressure in therapeutically resistant hypertensive patients

Circadian blood pressure and heart rate rhythms were determined in essential and renal hypertensive patients who failed to respond to drug therapy. Indirect ambulatory blood pressure and heart rate recordings were measured in 31 subjects for 24 hours. Essential hypertensive patients exhibit 'white coat hypertension', are normotensive outside the clinic and have a higher awake than sleep blood pressure. Blood pressure and heart rate of renal hypertensive patients do not increase in the presence of a physician and there is no difference between awake and sleep values. In contrast to patients with essential hypertension, the circadian fluctuations of blood pressure were depressed in renal hypertensive patients. We conclude that essential hypertensive patients who appear clinically uncontrolled are in fact well controlled in their domestic environment, whereas renal hypertensive patients are consistently uncontrolled. Ambulatory monitoring may help in differentiating the various types of patient and in the evaluation of antihypertensive therapy

Prevalence of biochemical and immunological abnormalities in rheumatoid arthritis

Tile prevalence of biochemical and immunological abnormalities was studied in a group of 256 patients with rheumatoid arthritis (104 coloureds, 100 whites and 52 blacks). The most common biochemical abnormalities detected were a reduction in the serum creatinine value (43,4%), raised globulins (39,7%), raised serum alkaline phosphatase level (42,3%), reduction in serum albumin value (8,1%), a mild rise in serum creatinine value (6,6%), and a raised serum y-glutamyltranspeptidase (GGT) level (6,5%). The prevalence of a rise in the GGT was less frequent than reported in other published studies. The immunological abnormalities noted were a positive rheumatoid factor (78,9%), positive anti-nuclear factor (36%), raised serum IgG (43,3%) and IgA (10,5%) values, positive smooth-muscle antibody (12,5%) and elevated double-stranded anti-DNA antibody levels (2,3%). Inter-group comparisons showed that the serum IgG and IgA and total globulins were significantly higher in blacks and coloureds than whites; these findings may be related to a higher prevalence of malnutrition and infection in childhood in these communities. There were no significant inter-group differences that could be attributed to rheumatoid arthritis

Altered calcium binding to erythrocyte membranes in essential hypertension: relation to magnesium

Abnormal cellular ion transport resulting in altered membrane control over intracellular calcium may be aetiologically related to essential hypertension. Cell membrane calcium binding, which is influenced by magnesium, is an important membrane system involved in cellular calcium regulation. In this study the relationships between erythrocyte calcium binding and extra- and intracellular calcium and magnesium concentrations were determined in essential hypertensive patients (52 black, 24 white) and normotensive controls (52 black, 26 white). Calcium depletion of the erythrocytes by MgCl2 and EDTA resulted in the removal of more calcium ions from the outer erythrocyte membrane in the hypertensive group compared with the normotensive group. This may be considered as evidence of increased calcium binding to the outer cell membrane in essential hypertension. Calcium binding was greater in the hypertensive males compared with the females. In black hypertensives, serum and erythrocyte magnesium concentrations were significantly increased. In white hypertensives, serum calcium was significantly decreased and erythrocyte calcium significantly raised. Serum and erythrocyte magnesium correlated inversely with the amount of calcium released from the membranes in the black hypertensive group. The results of this study suggest that changes in magnesium levels may contribute to altered cell membrane calcium binding in essential hypertension

Racial differences in cell membrane ATPases and cellular cation content in urban South African normotensive and hypertensive subjects

Platelet and erythrocyte membrane Na+,K(+)-ATPase, Ca(2+)-ATPase and Mg(2+)-ATPase activities and platelet, erythrocyte and serum magnesium, calcium, sodium and potassium concentrations were determined in black (n = 52) and white (n = 24) essential hypertensive patients from the city of Johannesburg in South Africa. The hypertensive groups were matched for age and body mass with black (n = 52) and white (n = 26) normotensive controls. In the black group, platelet and erythrocyte membrane ATPase activities were significantly depressed in the hypertensive subjects. In the white group, there were no significant differences for any of the ATPases studied between the normotensive and hypertensive subjects. Platelet sodium and calcium were significantly increased and serum magnesium, serum potassium, platelet magnesium and erythrocyte magnesium significantly decreased in the black hypertensive group compared to the black normotensive group. In the white hypertensive patients, platelet sodium and calcium were significantly raised and platelet magnesium significantly decreased compared to the normotensive controls. In blacks, platelet magnesium and ATPase activity were negatively correlated with mean arterial pressure. Unlike whites, black hypertensives have widespread magnesium changes with associated cell membrane ATPase depression and cytosolic sodium and calcium accumulation. These results suggest possible racial differences in cellular cation regulation in essential hypertension

Intracellular Mg²⁺, Ca²⁺, Na⁺ and K⁺ in platelets and erythrocytes of essential hypertensive patients: relation to blood pressure

Alterations in intracellular cation metabolism have been implicated in the pathophysiology of essential hypertension. Total magnesium, calcium, sodium and potassium levels were studied in serum erythrocytes and platelets, from 154 subjects (76 hypertensive and 78 normotensives; 104 blacks and 50 whites). In the combined black and white hypertensive group, platelet sodium and calcium and erythrocyte calcium were elevated and serum potassium, serum magnesium and platelet magnesium decreased. In the black hypertensive patients, platelet sodium and calcium and erythrocyte calcium were increased, whereas serum magnesium, serum potassium, platelet magnesium and erythrocyte magnesium were decreased. In the white hypertensive group, platelet sodium and erythrocyte calcium were raised and platelet magnesium was decreased. In the black hypertensive patients, serum and platelet magnesium and serum calcium were negatively and erythrocyte and platelet calcium positively correlated with mean arterial pressure. In the white hypertensive patients platelet sodium was directly related to mean arterial pressure. These results suggest that intracellular sodium and calcium overload and magnesium depletion may be important in the pathophysiology of hypertension. Magnesium disturbances are more consistent and widespread in black hypertensive patients than in white hypertensive patients

Magnesium, calcium, sodium and potassium status in normotensive and hypertensive Johannesburg residents

Serum magnesium, calcium, sodium and potassium, and erythrocyte magnesium, sodium and potassium levels were measured in a selected group of 296 urbanised black male labourers in Johannesburg. Of these, 214 subjects were normotensive and 82 were hypertensive. The aim of the study was to examine the relationship between serum and erythrocyte electrolytes, specifically magnesium and calcium, and blood pressure in this population sample. The results showed a significant decrease in serum magnesium, calcium and potassium in the hypertensive subjects. Red blood cell magnesium was significantly lowered and red blood cell sodium was significantly raised in this group. A significant inverse correlation was found between serum magnesium and blood pressure, erythrocyte magnesium and blood pressure, serum calcium and blood pressure, and serum potassium and blood pressure. A positive correlation was observed between erythrocyte sodium and blood pressure. Of all the electrolytes assessed, magnesium (serum and erythrocyte) correlated most closely with blood pressure. The data reported here suggest that body magnesium and its interactions with calcium, sodium and potassium may, in certain groups of individuals, play an important role in the development and maintenance of high blood pressure

Hypertension, alcohol and cations in urban black and coloured South Africans

Epidemiological evidence shows a positive relationship between alcohol consumption and blood pressure. High alcohol intake and hypertension are common in urban South African men. Relationships between mean arterial pressure (MAP), serum gamma-glutamyltransferase (GGT) as an index of alcohol intake, age, mass and levels of cations in the serum and erythrocytes were investigated in normotensive and hypertensive black and coloured men. Serum levels of potassium, magnesium and calcium and the red blood cell magnesium level were found to be significantly decreased in the black hypertensives. Serum GGT was equally raised in normotensive and hypertensive blacks and was positively correlated with systolic blood pressure in the hypertensive subjects. The coloured hypertensives were heavier, older and had significantly higher serum GGT levels than their normotensive counterparts. Serum GGT was positively correlated with MAP in the coloured subjects. No consistent relationships were found between GGT and blood cations. These data suggest that in younger black subjects alcohol is associated with systolic blood pressure only once hypertension has developed. Other factors, such as cations, may be more important than alcohol in the pathogenesis of hypertension in this group. Alcohol consumption is an important risk factor in coloured hypertensives