Studies in preventive nephrology: blood pressure and proteinuria in the population.

The evolution of three generations of anti-hypertensive drugs has produced more than less effective therapy. Mild hypertension is a definite risk factor and it is responsible for the bulk of complications in the population and must be treated. Community control of high blood pressure is feasible and effective. The third generation drugs seem to have specific reno-protective attributes.

Studies of preventive nephrology: self-urinalysis as a feasible method for early detection of renal damage.

The ever expanding pool of ESRF patients is exerting considerable strain on the health care resources of all nations of the world. Rationing, in one form or the other has therefore become the norm for most countries. Because dialysis prolongs life and is more readily available, and because ethically acceptable donor kidneys remain in short supply, thus limiting the potential of renal transplantation, this rather exasperating situation is bound to continue unless the entry point into the pool can be actively tacked. As part of our initial effort in this direction, we have examined the feasibility of self urinalysis by the general population as an epidemiological tool for detecting evidence of early renal damage by a total population cross-sectional survey of Faizia East Primary Health District (FEPHD) of Buraidah, capital city of the Gassim region of Saudi Arabia. Out of a de facto population of 7,695, 75.37% (5,800) cooperated fully. Majority of those who could not cooperate (881 [11.44%]) were infants and children. A total of 969 subjects (12.59%), mostly males at work, were not available. Only 45 (0.58%) subjects refused to participate. Housewives were significantly more amenable to the organisation of family self-urinalysis than head of the family (92.2% vs 61.4%; chi square = 321.78; df: 3; P < 0.0001). The mean family size was 7.82 (+/- SD: 3.82). Above the age of 4 years, 66.5% of males (2108/3170) as against 81.7% of females (2,641/3232) were able to carry our self-urinalysis. 11.76% of boys and 8.5% of girls below the age of 5 years were able to carry out self-urinalysis. Only 0.05% of male subjects and 0.03% of females failed to interpret colour change for proteinuria correctly. Similar remarkable competence was demonstrated for glycosuria by the population. We conclude that self-urinalysis is quite feasible in the general population, even if illiterates, if young. It can form a sound foundation, if properly harnessed, for a renal registry.

Some aspects of the pattern of systemic hypertension in the adult population of Gassim, Saudi Arabia: age distribution of the subsets of hypertensives.

As part of our studies in prevent nephrology, we have recorded causal blood pressure during a total population cross-sectional survey of the Faizia East Primary Health District of Buraidah (FEPHD), capital of Gassim region of Saudi Arabia. Out of 5671 subjects whose blood pressure could be recorded, 2222 were above 19 years of age and constituted our adult population. For this report, hypertension have been defined as equal to and greater than 140/90 mm Hg. Total hypertensive population had been divided into three subsets, based on this basic definition, namely combined systolic and diastlic hypertension (S/DHPN), isolated systolic hypertension (ISHPN) and isolated diastolic hypertension (IDHPN), a format which is not generally clear in previous studies on the subject. The overall prevalence of systemic hypertension was found to be 23.58%, which is lower than the figure of 36% for USA (pre-primary prevention intensive campaign). It is assumed that all the three subsets mentioned above have been used in calculating the latter. Although males tended to be more hypertensive than females (OR = 1.22; Chi Square = 3.89; P = 0.05; C.I.: 1.00 < OR < 1.49), the marginal difference (25.7% vs 22.10%) was largely due to the IDHPN subset (OR = 1.73; Chi Square = 4.48; P = 0.034; C.I.: 1.01 < OR < 2.96). In both the S/DHPN and ISHPN: statistical significance was not achieved. Significantly, ISHPN subset constituted the bulk--56.68%--of the hypertensive population while IDHPN constituted the least--11.64%. When analysed into 10-year-age cohorts, ISHPN showed the steepest rise in prevalence with age. Rather suprisingly, the IDHPN did not rise with advancing age while the S/DHPN slope was in between the two. We are unable to identify this pattern in our literature search on the subject. We cannot assess its significance by this study, but we wonder whether or not it carries any prognostic significance in terms of target organ damage. It is possible that this pattern may be peculiar to the sub-region but it certainly is not spurious and in our view deserves further scrutiny. We wish to suggest that clear definition of the three subsets of hypertensive population should be mandatory when defining prevalence. This may provide some further clues in the prognosis and pathogenesis of target organ damage.

Blood pressure pattern in Saudi population of Gassim.

Blood pressure pattern for the Kingdom of Saudi Arabia has not been defined. In a total cross-sectional population survey of the Faizia East Primary Health District of Buraidah, capital of Gassim region, Saudi Arabia, 5671 subjects out of a de facto population of 7695 got their blood pressure recorded. The study district consisted of an urban section and a rural sector. Mean systolic and diastolic blood pressure were computed for the total population in conventional 5-year age cohorts as well as in an arbitrary functional age groups. The curve pattern and trends of the percentiles, were defined. Mean blood pressure (systolic and diastolic) was found to rise with age in both genders (male SBP: r = 0.66, P < 0.000001: female SBP: r = 0.58, P < 0.00001; male DBP: r = 0.53, P < 0.00001; female DBP: r = 0.45, P < 0.00001) and to correlate significantly with BMI. Both systolic and diastolic values were consistently higher in females than males. Overall means (+/- SD) were: for SBP, male 109.9 (+/- 21.57) vs female 114.33 (+/- 21.22) mm Hg; df: 5669: P < 0.00000; CI: -5.5, -2.0; for DBP, male 62.85 (+/- 16.89) vs female 64.67 (+/- 14.99) mm Hg; df: 5669; P < 0.0000; CI: -2.65, -0.989. Proteinuria (macroalbuminuria) was found to correlate positively and very significantly with both systolic and diastolic blood pressure: for SBP: r = 0.074, P < 0.0001; DBP: r = 0.055, P < 0.0001. Perhaps more significantly, in the context of preventive nephrology, is the observation that the intercept of the regression line with blood pressure was below the level conventionally regarded as hypertensive, suggesting that nephron damage may have occurred at this lower level. Overall mean diastolic blood pressure but not systolic was found to be significantly higher in the rural environment than the urban setting: mean rural DBP: 66.43 (+/- 15.699) vs urban: 62.78 (+/- 78); P < 0.00001; rural SBP: 113.71 (+/- 23.95) vs urban: 112.69 (+/- 19.87), P = NS. No discernible effect of consanguinity in marriage on blood pressure could be detected in this study but we believe that further details are required before a definite statement can be made on this important subject. The percentiles presented can only be regarded as foundation figures requiring further validation before they can be useful in determining cut-off levels for hypertension for the Saudi population.

Body mass index (BMI) in the Saudi population of Gassim.

In a total cross-sectional population survey of the Faizia East Primary Health District of Buraidah, Gassim region of Saudi Arabia, 6,044 (2727 male and 3317 females) subjects out of a de facto population of 7695 got their BMI computed because infants and restless or bedridden subjects could not be examined. Mean (+/- SD) and percentiles (25th & 75th) were calculated in the conventional 5-year age cohorts as well as in functional age groups, namely, 0-5, 6-12, 13-49, 50-69 and 70+ years. 5th, 10th, 25th, 50th, 75th, 90th and 95th percentiles were computed only for the functional age groups. In general, the trend was for BMI to increase with age in both genders but the curve pattern showed some plateauing from about the age of 50 with slight decline in later life. Females had significantly higher indices than males, this becoming quite prominent from the 10-14 year age cohort. This difference persisted irrespective of the types of age grouping or residential location. Overall means (+/- SD) were 20.14 +/- 5.98 vs 22.22 +/- 7.21 for males and females respectively; df: 5771; p = 0.0000; 95% CI: -2.43, -1.735. Subjects in the urban living environment had significant higher indices than their rural counterpart: (21.666.92 vs 20.446.33: df: 5771; P = 0.0000; 95% CI: 1.595, -0.840). From the age of 15 about one quarter of females are overweight (BMI at the 75th percentile > 25) and from 30 years the same proportion are frankly obese (BMI > 30). Both systolic and diastolic blood pressure were significantly positively correlated with BMI in both genders: male SBP: r = 0.22, P < 0.0001; male DBP: r = 0.21, P < 0.00001; female DBP: r = 0.18, P < 0.00001.

Thyroid function in haemodialysed patients of Gassim, Saudi Arabia: TRH stimulation.

To study the hypophysical-pituitary-thyroid axis in Saudi patients on (RDT), 200 units of TRH were given intravenously predialysis to each of 21 such subjects. As expected (TSH) rose promptly within 30 minutes followed by a gentle decline at 60 minutes. A more gentle rise was also noted in T3 which continued for the 60 minutes of observation. Rather unexpectedly, T4 level was noted to show a reciprocal decline. To our knowledge, this pattern has not been defined in literature. In 12 patients (GH) was noted to rise promptly within 30 minutes followed by a gentle decline at 60 minutes. (LH) and (FSH) did not follow any definite pattern as observed for T3 and T4. Since the oral preparation of TRH is now available, can (TRH) be effectively used to treat renal dwarfism?

Studies on preventive nephrology: Systemic hypertension in the pediatric and adolescent population of Gassim, Saudi Arabia.

Casual blood pressure was recorded for subjects of Faizia East Primary Health District during a cross-sectional population survey. Valid information was obtained from 5671 subjects, out of which 3299 (1561 males and 1738 females) were between the ages of three and 18, constituting therefore the pediatric/adolescent (P/A) sector of our study population. The prevalence of hypertension (HPN), defined as A(3) 95th percentile for total HPN population (mild and severe) and A(3) 99th percentile for severe, was calculated for the three-year age cohorts suggested by the Task Force on Blood Pressure Control in Children (1987). The three subsets of HPN were derived from the suggested cut-off levels without any modifications. Overall prevalence of HPN was, for the P/A, found to be 10.65% (351/3299). Females in all the age cohorts were significantly more hypertensive than males, overall gender prevalence being 7.94% (124/1561) for males against 13.06% (227/1738) for females: P=0.0000019; CI: 0.45

Contrasting influence of the living environment and gender on systemic hypertension in Saudi population of Gassim, Saudi Arabia.

In a cross-sectional total population survey of Faizia East Primary Health District of Buraidah, which is divided into an "urban" and "rural" sections, casual blood pressure was recorded in 5671 subjects. 2222 (910 males) were adults (> 19 years). 3299 (1561 males) were between 3-18 years, making the paediatric/adolescent cohort of the population. The rest were below 3 years and were not included for calculations in this report. For adults, HPN was defined as > or = 140/90 mm Hg and P/A it was > or = 95th percentile for the age cohorts 3-5, 6-9, 10-12, 13-15 and 16-18 years as recommended by The Task Force for Blood Pressure Control in Children (1987). Each of the three subsets of HPN were derived from these basic definitions without modification. In the adults population, overall prevalence (S/DHPN + ISHPN + IDHPN) was 23.58% (524/2222) and gender prevalence was marginal in favour of males (25.71 vs 22.1% for males and females respectively; OR: 1.22, chi square = 3.89; p = 0.05; CI: 1.00 < OR < 1.49). By contrast, overall HPN prevalence in P/A was 10.64% (351/3299) and in all the age cohorts, girls were very significantly more hypertensive than boys. Overall figures were 13.06 vs 7.94% respectively for girls and boys; OR: 0.57; chi square = 22.65; p < 0000019; CI: 0.45 < OR < 0.73. Only in severe HPN (> or = 99th percentile) in 16-18 year age cohort did male preponderance become obvious. When the influence of the living environment was examined, in adult population (urban: 40,001; rural: 1670 subjects), for all age cohorts the rural environment which is largely inhabited by the unsophisticated Bedouins living close to their livestock, significantly predisposed to HPN as compared to the urban setting. Overall figures are 19.95 vs 32.60%, urban vs rural respectively: OR: 0.52; chi square = 40.4; p < 0.000000; CI: 0.42 < OR < 0.64. On the other hand, in the P/A population (2301 urban, 998 rural) for the age cohorts 3-5 and 6-9 years the urban environment significantly predisposed to HPN. At 10-12 years the prevalence was virtually even (12.65 vs 12.71%; OR: 0.99; p: NS). Thereafter, i.e. 13-15, 16-18 year cohorts, the rural environment became more dominant, just like the adult pattern. In other words whatever the factors in the unsophisticated Bedouin "rural" setting which predisposes to HPN does not become operative until after childhood--after 12 years. This contrasting gender and environmental influence in our study population seems unique, being reported for the first time. It may be pointing us in new direction in the elucidation of the pathogenesis of HPN and should deserve further studies.

Hepatitis C antibodies in haemodialysis and pattern of end-stage renal failure in Gassim, Saudi Arabia.

As by the end of 1992, 96 (47 females; 49 females) patients were on regular dialysis treatment for end stage renal failure (ESRF) in 5 haemodialysis HD units, the Gassim region of Saudi Arabia. Because of lack of facilities, paediatric patients were under-represented, age range being 11 to 80 years. Systemic hypertension (47%), followed by hereditary/congenital conditions (23%) and non-insulin dependent diabetes mellitus NIDDM (19%) were the most common causes of ESRF in the region. One patients developed ESRF 14 years after donor nephrectomy. Overall prevalence of HCAb was 50% with a range of 17.24% to 83%. Based, especially, on the findings in two of the units which between them handle 57% (55/96) of the patients, we believe that the practice of machine isolation policy (MIP) rather than blood transfusion is largely responsible for this wide variation in prevalence between the centres. Considering the very high overall prevalence of the Kingdom, we suggest the MIP should no longer be optional and should be part of the universal infection precautions for HD patients. Comparing Gassim with findings from Taif, there may be some variation in the pattern of ESRF between different parts of the Kingdom. More reports will be needed to document this. Donor nephrectomy as a cause of ESRF is being recorded for the first time in the Kingdom. Vigilance is important. Similarly, we believe that sexual intercourse as a probable route of hepatitis C virus HCV transmission is being recorded for the first time in the Kingdom.

Studies on preventive nephrology: pattern of the subsets of hypertension in the paediatric, adolescent and adult population of Gassim, Saudi Arabia.

As part of our studies in preventive nephrology, we have recorded the casual blood pressure during a total population cross-sectional survey of the Faizia East Primary Health District (FEPHD). A total of 5671 subjects had adequate records. Of these 2222 were adults (> 19 years). The prevalence of systemic hypertension (HPN) was calculated, using as cut-off levels, > or = 140/90 for the adult population and > or = 95th percentile as recommended by the Task Force for Blood Pressure Control in Children (1987) for the paediatric and adolescents (3-18 years). Using these definitions without modification, the three subsets of HPN viz. combined systolic/diastolic (S/DHPN), isolated systolic (ISHPN) and isolated diastolic (IDHPN) were derived for each of the age cohorts studied-10-year age cohorts for the adults and the Task Force 3-year age cohorts for the paediatric/adolescent (P/A) population. In both adult and P/A population ISHPN constituted the bulk of the hypertensive population (56.68% for the adults and 51.57% for P/A). the IDHPN subset was the least for adults making up 11.64% while the S/DHPN was in between constituting 31.68%: For the P/A population S/DHPN was the least, 15.95% and IDHPN (32.48%) was in between. When distributed into 10-year age cohorts for the adults, ISHPN showed the steepest gradient depicting increasing prevalence with advancing age. On the other hand, IDHPN did not rise with age; if at all, it tended to fall. The slope for S/DHPN was sandwiched in between. For the P/A population, for all the 3-year age cohorts, and for all the three subsets, there was an initial peak in childhood followed by a decline in adolescence. However, some variations were discernible in each subset. ISHPN in girls peaked at 10-12 before declining but in boys it virtually followed an even keel. IDHPN, in both boys and girls peaked sharply at 6-9 before a rapid decline in prevalence into adolescence. S/DHPN also peaked at 6-9 but both the upward slope and the subsequent decline were more gentle than the other subsets. When viewed together for our study population, assuming equivalence in cut-off levels for HPN, both ISHPN and S/DHPN seem to exhibit a bimodal curve, with one peak in childhood and a second rise in adulthood continuing into old age. IDHPN showed a unimodal curve, with the one peak in childhood followed by a continuing decline through adolescence into adulthood to virtual disappearance in old age. We believe these slopes may have prognostic significance which are not entirely clear at the moment but our findings reinforce the importance of the systolic blood pressure and that diastolic blood pressure alone should no longer be used as the index treatment or complication of high blood pressure.

Studies on the prevalence of renal disease and hypertension in relation to schistosomiasis. III. Proteinuria, haematuria, pyuria and bacteriuria in the rural community of Nigeria.

Midstream specimen of urine was collected from the total population of two rural communities in the immediate environs of Ibadan. One has a higher and the other a low endemicity of urinary schistosomiasis. Proteinuria, haematuria, pyuria and bacteriuria were found to be significantly more frequent in the area of high than low endemicity.

PIP: A clinical epidemiological study was conducted to determine the association, if any, between the incidence of urinary schistosomiasis and urinary tract infection. The urinary excretion of protein and cells was also studied. Data was collected from 2 rural Nigerian communities--1 with a low level of endemic urinary schistosomiasis and the other with a high level. Midstream urine specimens were collected from the 2 populations. The laboratory procedures are described and the findings are presented in detailed tables. Proteinuria, haematuria, pyuria and bacteriuria were found to occur at significantly higher levels in the area of high than low schistosomiasis endemicity.

Studies on the prevalence of renal disease and hypertension in relation to schistosomiasis. V. Radiological findings: plain X-ray abdomen and intravenous pyelogram.

After studying two rural communities with varing endemicity of urinary schistosomiasis by total cross-sectional population survey, a stratified sample was obtained using defined criteria. Plain X-ray abdomen and intravenous pyelogram were carried out on the sample. Findings on plain X-ray of the abdomen, using the usual parameters of psoas and kidney shadows in the Nigerian, indicate that the two communities studied are similar but urinary calculi and urinary tract distortion are significantly more prominent in the community with the higher endemicity of urinary schistosomiasis.

PIP: Radiologic findings are reported from 2 communities, 1 with high and the other with low endemicity of urinary schistosomiasis, of Ibadan. After studying the 2 rural communities with varying endemicities of urinary schistosomiasis by total cross-sectional population survey, a stratified sample was obtained using defined criteria (all cases of proteinuria of 100 mg%; all cases of diastolic blood pressure of 90 mm or greater; all cases with significant bacteriuria; 20% of cases with history of nocturia; and age-selected trace and absent proteinuria for 20% of cases). Plain X-ray abdomen and intravenous pyelogram were carried out on this defined sample population. Findings on plain abdominal X-ray, using the usual parameters of psoas and kidney shadows in the Nigerian, indicated that the 2 communities studied were similar, but urinary calculi and urinary tract distortion were significantly more prominent in the community with the higher endemicity of urinary schistosomiasis. X-rays are not included in the text, instead tabular information on the morphology of renal areas is presented.

Studies on the prevalence of renal disease and hypertension in relation to schistosomiasis. IV. Systemic blood pressure hypertension and related features.

Two comparable rural communities but with varying endemicity of urinary schistosomiasis in environs of Ibadan, Nigeria, have been studied by a total cross-sectional population survey. It has been found that:- (i) schistosomiasis does not predispose to raised blood pressure (ii) both diastolic and systolic blood pressure increase with age. (iii) prevalence of systemic hypertension is higher in females than males (iv) body weight and height are related to hypertension in both males and females (v) parity would seem to be related to hypertension in the females (vi) except in the younger female group (1--19 years) where polyuria, frontal headache, palpitations appear related to systolic hypertension, raised blood pressure would appear to have no symptoms. In particular headache in any part of the head bears no clear relationship. (vii) The majority of hypertensives would appear to belong to the primary variety but proteinuria among females has been found to be significantly related to hypertension.

PIP: A clinical epidemiological study was conducted to examine systemic blood pressure, hypertension, related features, and the possible influences of urinary schistosomiasis. Data was collected from 2 Nigerian communities--1 with a low level of endemic urinary schistosomiasis and the other with a high level. All data is graphed and tabulated. The study showed that no differences in systolic or diastolic blood pressure could be attributed to urinary schistosomiasis. In fact, hypertension was more common among the population with the low levels of schistosomiasis endemicity. This does not suggest that schistosomiasis protects against hypertension; other factors, especially age and parity in that population, might contribute to hypertension. The study showed that age causes an increase in both systolic and diastolic pressure. Females were more susceptible to systemic hypertension than males. Body weight and height in both males and females and parity in females seemed to be related to hypertension. A headache symptom was not found to be related to hypertension.

Further details of third recorded case of redwater (Babesiosis) in man.

Clinical details and laboratory and postmortem findings of a human case of redwater (piroplasmosis or babesiosis) caused by Babesia divergens. This is the third proved case in man. All three patients had had splenectomies.