Factors influencing the development of malignant hypertension in Nigeria.

Hypertension prevalence rates remain comparatively low in Nigeria, although the associated morbidity and mortality including that due to malignant hypertension (MHT) is considerable. To determine the factors that may be associated with the development of MHT we compared 74 patients with essential MHT (age 48 +/- 9 years, 59 male, blood pressure (BP) 234 +/- 31/140 +/- 17 mm Hg) with 74, age, gender and BP-matched patients with essential benign hypertension (BHT) (49 +/- 8 years, 60 male, 227 +/- 26/136 +/- 15 mm Hg). Body mass index was higher in the BHT [corrected] group by 1.3 (95% Cl: 0.5 to 2.1, P < 0.01). In the subset (25 MHT, 43 BHT) in whom hypertension had been diagnosed before presentation, duration of hypertension was shorter (P < 0.05) in the MHT group. Patients with MHT, were more likely to have been receiving inadequate therapy in the months before (OR 2.7, 95% Cl: 1.4 to 5.4), showed a decreasing proportion with increasing socio-economic class (chi2 = 5.79, P < 0.02) and had been exposed to a greater degree of stress (OR 3.5, 95% Cl: 1.7 to 7. 1). Smoking (OR 1.1, 0.6 to 2.3), alcohol use (OR 0.9, 0.5 to 1.8) and contraceptive pill use (OR 0.9, 0.1 to 8.6) did not impart excess risk. MHT is associated with the underprivileged and measures aimed at raising the general awareness and the socio-economic level of the people are expected to produce a decline in the incidence of MHT. Journal of Human Hypertension (2000) 14, 171-174.

Racial differences in ambulatory blood pressure and echocardiographic left ventricular geometry.

We examined the racial differences in left ventricular (LV) geometric pattern in relation to 24-hour ambulatory blood pressure (BP) monitoring and the presence or absence of a nocturnal BP dip. Our study confirms the blunting of nocturnal BP dip among black hypertensives. Body mass index, rather than race, was a major determinant of left ventricular hypertrophy. We did not observe a difference in prevalence of left ventricular hypertrophy by race. However, left ventricular adaptation to hypertension differed in hypertensive black and white individuals; whereas most of the white patients with Stage 1-2 hypertension had a normal ventricular pattern, LV concentric remodeling and concentric hypertrophy were the most common adaptive ventricular patterns in blacks with Stage 1-2 hypertension. A six-fold higher prevalence of concentric remodeling was observed in blacks as compared with whites. The impaired nocturnal BP dip in blacks may contribute to the different hemodynamic pattern. Determinants of myocardial oxygen consumption were significantly higher in black hypertensives.

Short-term course of renal function in accelerated hypertension.

Thirty-four patients with primary accelerated hypertension were studied regarding the effect of BP on renal function and the association between fundal grade and renal function before treatment; and the changes in renal function on normalization of BP in 12 patients. Mean arterial pressure was negatively correlated with serum creatinine (r = -0.44, P < 0.02) and there was no significant difference in serum creatinine or in the occurrence of renal failure between patients with grade III (n = 21) and grade IV (n = 13) retinopathy, (P = n.s. and X2 = 0.172 P = n.s. respectively). Twenty-two patients required dialysis at presentation. Serum creatinine rose in 12 other patients on reduction of BP; 7 patients with serum creatinine level < or = 3.2 mg/dL (283 umol/L) at presentation never required dialysis in the 3 months following reduction of BP while those with levels > or = 3.6 mg/dL (319 umol/L) did. In accelerated hypertension, renal function is partly maintained by the blood pressure and dialysis may be required soon after presentation or normalization of BP.

Pattern of adrenocortical response to the stress of severe illness in Nigerians.

Twenty-eight severely ill, hospitalized Nigerian patients, 18 males and 10 females with a median age of 41 years (group I) and 20 stable ambulatory patients, 11 males and 9 females with a median age of 42.5 years (group II), had early morning plasma cortisol measurements. Ten healthy young Nigerian males with a mean age of 22.1 years (group III) had plasma cortisol estimations during insulin tolerance test. The mean (+/- SD) cortisol values for the three groups in nmols/l were as follows: group I--389.3 (202.4), group II--267.1 (67.4), group III-624.5 (81.1). The results for the group III healthy controls represent the peak (60 mins) value during insulin induced hypoglycemic stress. A one way analysis of variance (ANOVA) demonstrated a statistically significant difference between the three mean cortisol values, P < 0.001. A pair-wise comparison using the t-test also showed significant differences between the groups, P < 0.05 in each case. An important observation was the variable pattern of cortisol stress response in different types of illnesses. Cases of stroke appeared to be associated with increased cortisol stress values (Z-score + 5.67) while patients with hypotension (B.P. < or = 90/60) and those on Rifampicin had reduced cortisol responses (Z-scores - 3.66 and 3.51 respectively). However, no firm recommendations can as yet be made regarding the usefulness of corticosteroids in life-threatening illnesses among Nigerians, other than those for which steroids are known to beneficial.

Neurological complication following tetanus toxoid immunization. A case report.

A 33-year-old Nigeria male developed fever, malaise, headache, muscle weakness and polyneurutis 24 hours after administration of tetanus toxoid. These manifestations however cleared within 72 hours. No other identifiable agents or predisposing factors were identified to explain this phenomenon.

The clinical presentation of malignant hypertension in Nigerians.

To document the clinical presentation of malignant accelerated hypertension in Nigerians, 56 patients were studied between 1987 and 1989 (30 months). Age range was 16 to 55 years with 59% in the range of 30-49 years; 47 were male. Mean systolic and diastolic blood pressures were 217 mmHg and 146 mmHg, respectively. Thirty patients had grade III and 26 grade IV hypertensive retinopathy. Mean body mass index was only 22.4 in the 21 patients who had no evidence of fluid retention. Seventy-five percent of patients had no awareness of hypertension. Essential hypertension accounted for 66%, chronic renal disease 32% and renal artery stenosis 2% of cases. The most common clinical features were headaches (80%), fatigue (68%), oliguria (52%), heart failure (46%), weight loss (41%), and poor vision (21%). Multiple symptoms were common and 24 patients had both renal and cardiac failure. Laboratory features included microscopic haematuria (100%) and proteinuria (100%). In 37 patients with essential hypertension, renal failure was a complication in 60%. Microangiopathic haemolytic anaemia was present in 23 patients. In addition to eight deaths from renal failure in the acute stage, 23 of these patients required long-term dialysis. Thus, malignant accelerated hypertension was associated with high morbidity, especially renal failure; it primarily afflicted patients in their prime years. Known survival at one year was 37.5%, but some patients were lost to follow-up.