Trends of HIV infection among injection drug users in Brazil in the 1990s: the impact of changes in patterns of drug use.

BACKGROUND: Santos Metropolitan Region (SMR), State of Sao Paulo, historically is well known as being one of the areas with the largest number of AIDS cases in Brazil, especially among injection drug users (IDUs). The main objective of this study was to assess the effects of changes in drug-using patterns among IDUs on trends in HIV infection among IDUs in the 1990s. METHODS: During 1991 through 1992 (wave 1; n = 214), 1994 through 1996 (wave 2; n = 135), and 1999 (wave 3; n = 108), we conducted three cross-sectional studies of IDUs. All participants were interviewed and tested for antibodies to HIV. FINDINGS: The overall sample population was 69% male, and 87% of the sample population was under 40 years old. Eighty-four percent of the population had less than 9 years of education. HIV seroprevalence was 63% in wave 1, 65% in wave 2, and 42% in wave 3 ( p <.001). Smoking of crack cocaine increased from 11% in wave 1 to 60% in wave 2 and 67% in wave 3 ( p <.001). The prevalence of frequent injections (>5 per day) decreased from 42% in wave 1 to 30% in wave 2 and 15% in wave 3 ( p <.001). INTERPRETATION: HIV prevalence decreased as injection frequency decreased and crack cocaine use increased. In SMR, patterns of drug use have been affecting the HIV epidemic more than scant public health intervention.

[Tracking indices of the blood pressure in a longitudinal study in infants and adolescents]. / Indices de tracking da pressão arterial num estudo longitudinal de crianças e adolescentes.

OBJECTIVE: The objective of this study was to assess the degree of BP Tracking from childhood to adulthood and to evaluate whether high BP levels persist over time and progress to adult hypertension. PATIENTS AND METHODS: Two hundred and twenty-two healthy schoolchildren living in the North of Portugal were assessed at 17 year intervals, starting in 1979 (cohort 1) aged 5 to 18 years, and again in 1996 (cohort 2). Tracking indices (Ti) were calculated as follows: Ti = (2x + y-z) /N/0.89, where x, y and z refer to the total number in the same, adjacent and remote trisections, respectively, and N = x + y + z. If Ti > 1 there is positive tracking. RESULTS AND CONCLUSIONS: For systolic and diastolic blood pressure, all Ti were greater than 1.0. All individuals that remained in the 3rd tertil, 17 years later, weigh more and are more obese than those of the 1st tertil. 56.6% of the individuals that belong to the 3rd tertil are now hypertensive, which means that a significant percentage of the children with high blood pressure in the first survey will be hypertensive in the future.

Factor analysis, a more accurate method to be used in epidemiological studies of blood pressure in children.

The aim of our study is to evaluate whether factor analysis is better able to explain the variability of systolic blood pressure (SBP) and diastolic blood pressure (DBP) when compared with regression analysis, which is the usual tool to study a set of variables related to blood pressure (BP). SBP, DBP, weight, height, BMI, triceps skin-fold, sexual maturation and rurality were studied in 889 children aged 5-18 years (389 boys and 500 girls). The proposed method transforms any set of variables into a set of new variables (factors) which are uncorrelated with each other. One of the factors obtained clearly explains the BP variance of the. With this method, the algorithm accepts all meaningful variables, while regressions reject most of them. This method also explains a larger amount of BP variability, losing as little information as possible. In our sample the percentage of the total variance (communality) explained by the three factors was 80.3% for SBP, 88.1% for DBP in males, 79.3% for SBP and 90.7% for DBP in females. For the same sample, regressions only explained 41.2% in males and 41.9% in females for SBP, 40.9% in males and 47.2% in females for DBP. In conclusion, this method is more accurate for epidemiological studies producing a better overall score than regression analysis, losing almost no information from the sample. Two important strengths of the proposed methodology are as follows. First, it yields a unique, easy to calculate and flexible cardiovascular index for children, thus circumventing the problem of making decisions based on two variables (SBP and DBP). Second, such an index is the result of a methodology where specific BP variability is isolated rather than explained.

Prevalence of high blood pressure in children and adolescents. Influence of obesity.

Obesity is associated with high blood pressure BP, mainly in adults. It has been suggested that body fat patterning plays a role in the etiology of hypertension. This relationship also exists in children, however it is less well known. The aim of this study was to evaluate the prevalence of high blood pressure (HBP) in children and adolescents, and the influence of obesity on this population, as well as the presence of familial aggregation for these factors. Eight hundred and eighty-nine children (389 boys and 500 girls aged 5-18 years) and their parents, from the North of Portugal were studied. Systolic blood pressure, diastolic blood pressure, weight, height, triceps skinfold, body mass index and sexual maturation were measured. The criterion of high blood pressure was defined as the BP being higher than the 90th percentile. All variables were converted to age and sex in specific "Z-scores". A SPSS package was used. We found 47 (5.2%) people of both sexes to have high blood pressure. The children of this group were compared with the normotensive group. These children were heavier (p < 0.005) and more obese (p < 0.0001) than the others. No difference was found for sexual maturation or height. The parents of the group with high blood pressure were heavier (p < 0.001) and more obese (p < 0.01) than the parents of the normotensive group. In conclusion, obesity is an important factor in children with higher values. Children with HBP are more likely to come from families with history of obesity. The identification of these risk factors in children is an important contribution to the prevention of cardiovascular disease in adulthood.

[Blood pressure in a population of youngsters and adults observed after 17 years]. / Estudo da pressão arterial numa população de jovens e adultos jovens observados após um período de 17 anos.

Many studies have assessed the blood pressure tracking among children and adolescents, but the results have been controversial. This study assessed the blood pressure tracking in 224 Portuguese school children and young adults following them for 17 years. The correlations obtained for systolic and diastolic blood pressure in both sexes are not very high, although positive and statistically significant. On the other hand, there was a stronger correlation between anthropometric variables and blood pressure and indices of obesity.

Renal adenoma: identification of two histologic types.

In this paper the morphologic characteristics of renal adenoma are studied in 4 groups of kidneys from 500 unselected autopsies performed for legal reasons, 5,000 autopsies from the files of a general hospital, 16 kidneys with adenoma and without carcinoma, and 200 kidneys with carcinoma. All the tumors were classified by pattern, cytology and sclerosis of the renal nontumoral stroma. The relationship between tumor size, tumor histological type and sclerosis was evaluated by statistical analysis. The differences in frequency were significant between the parameters size and histological type (p < 0.003), namely for solitary adenomas (p < 0.001). The differences in histological type observed in multiple adenomas were not significant (p > 0.05). The differences were significant between the extent of sclerosis and histological type (p < 0.002) and tumor size (p < 0.009). This study identifies two distinct groups of adenomas according to size, histological type and extent of sclerosis, and suggests that small adenomas of the mixed tubulopapillary type and with basophilic cells have little or no malignant potential. Conversely, adenomas with a solid or papillary pattern and clear cells are potentially malignant.

Aggregation of blood pressure in families: genetic and environmental influences.

A study was undertaken to determine whether parent-child blood pressure (BP) resemblances reflect parent-child similarities in body build. Those studied were 889 children, 5-18 years old, their parents and relatives because of recognized correlations between body build and BP in individuals, along with familial clustering of these variables. To maximize the likelihood of demonstrating correlations between BP and body build in family members, BP and anthropometric variables of parents whose children were in the upper quintile (group I) and lower quintile (group II) of the same variables were compared. Variance analysis has shown that group I children were heavier (P less than or equal to 0.001) and more obese (P less than or equal to 0.01) than group II. The parents of group I had higher systolic BP (P less than or equal to 0.001), diastolic BP (P less than or equal to 0.01), were taller (P less than or equal to 0.0001), heavier (P less than or equal to 0.001) and more obese (P less than or equal to 0.01), than the parents of group II. Parent-children BP resemblances reflect parent-children similarities in body build. The study of group I children and their families may give important information about determinants of high BP in children.