Caesarean sections in Mexico: are there too many?

This paper seeks to quantify the magnitude of caesarean sections in Mexican public health-care institutions in recent years, to characterize the evolution of caesarean section rates (CSR) during the last decade, and to estimate the possible economic cost caused by the excess of caesareans performed in these institutions. The study is based on data obtained from the health sector, both for Mexico in the 5-year period 1993-97 and for the Mexican State of Jalisco between 1983 and 1998. Linear regression analysis was used to evaluate time series, and "excess of caesareans" was considered the number of caesarean deliveries performed above the admissible 15% CSR. The results reflect that on the national level, more than one-quarter of the deliveries handled by public institutions ended in caesarean section for each analyzed year, and if the deliveries performed in private institutions are included, the national rate is around 30%. A marked increase in CSR can be observed in Jalisco between 1983 and 1998 (almost 50%); and the cost for the nation of this CSR excess in financial terms is highly significant: several millions of dollars--obtained from public funds--are spent annually and unnecessarily by health services. The findings suggest that the increase in CSR is a public health problem that has not been satisfactorily faced by the health sector authorities. Many unnecessary caesareans would undoubtedly be avoided if the policies of these public health-care institutions were to consider, as a priority, both the known higher risk implicit in a caesarean for the health of the mother and child, and the economic impact on the country and its health institutions of the excessive number of caesareans performed yearly.

[Effects of an educational intervention on plasma levels of LDL cholesterol in type 2 diabetics]. / Efectos de una intervención educativa sobre los niveles plasmáticos de LDL-colesterol en diabéticos tipo 2.

OBJECTIVE: To prove the benefit of an educational intervention for controlling LDL cholesterol levels in LDL cholesterol. MATERIAL AND METHODS: A quasi-experimental study was conducted; diabetic patients were randomly allocated to an experimental and a control group. The experimental group consisted of 25 patients and the control group of 24 patients. The educational intervention was organized through a reflection-action process. LDL cholesterol levels were measured at baseline and monthly during the nine months of the study. The groups were controlled for age and sex. Statistical analysis included Wilcoxon's test for ordinal variables. RESULTS: The intervention group had a mean value of LDL cholesterol of 148.4 +/- 21.3, compared to 185 +/- 24.1 in the control group (p < or = 0.05). CONCLUSIONS: The participative educational intervention contributed to improving the levels of LDL cholesterol, by promoting a lifestyle change in type-2 diabetic patients.

Using logistic regression to describe the length of breastfeeding: a study in Guadalajara, Mexico.

This study seeks, through a logistic regression model, to describe the pattern of breastfeeding duration in Guadalajara, Mexico, during 1993. A multistage random sample of children under 1 year of age (n = 1036) was studied; observational data regarding breastfeeding duration, obtained through a "status quo" procedure, were compared with prevalence rates obtained from the logistic regression model. Modeling the duration of breastfeeding during the first year of life rather than only analyzing observational data helps researchers to understand this process in a dynamic and quantitative way. For example, uncommon indicators of breastfeeding were derived from the model. These indicators are impossible to obtain from observational data. The prevalence curve estimated through the logistic model was adequately fitted to observed data: there were no significant differences between the number or distribution of breastfed infants observed and those predicted by the model. Moreover, the model revealed that less than 40% of the children were breastfed in the fourth month of life; the median age for weaning was 39.3 days; 55% of the potential breastfeeding in the first 4 months did not occur; and the greatest abandonment of breastfeeding in the first 4 months was observed in the first 60 days. Thus, logistic regression seems a suitable option to construct a population-based model that describes breastfeeding duration during the first year of life. The indicators derived from the model offer health care providers valuable information for developing programs that promote breastfeeding.

PIP: This study describes the pattern of breast-feeding duration in Guadalajara, Mexico, in 1993, using a logistic regression model. A multistage random sample of children under 1 year of age (n = 1036) was studied; observational data regarding breast-feeding duration, obtained through a "status quo" procedure, were compared with prevalence rates obtained from the logistic regression model. Modeling the duration of breast-feeding during the first year of life rather than only analyzing observational data helps researchers to understand this process in a dynamic and quantitative way. For example, uncommon indicators of breast-feeding were derived from the model. These indicators are impossible to obtain from observational data. The prevalence curve estimated through the logistic model was adequately fitted to observe data: there were no significant differences between the number or distribution of breast-fed infants observed and those predicted by the model. Moreover, the model revealed that less than 40% of the children were breast-fed in the fourth month of life. The median age for weaning was 39.3 days and about 55% of potential breast-feeding in the first 4 months did not occur. Lastly, the highest abandonment of breast-feeding in the first 4 months was observed in the first 60 days. Thus, logistic regression seems a suitable option to construct a population-based model that describes breast-feeding duration during the first year of life.

[The study of the smoking-related mortality in Jalisco, Mexico]. / Estudio de la mortalidad atribuible al tabaquismo en Jalisco, México.

BACKGROUND: In recent years, tobacco consumption its associated health problems have increased in Mexico. This study aims to describe the effects of tobacco use on mortality in the State of Jalisco, Mexico, in 1990. METHODS: 22 smoking-related diseases, for which there are estimates of relative risks of death were selected; smoking-attributable mortality fractions for each disease per sex, were calculated. This made it possible to estimate smoking-attributable mortality rates, years of potential life lost (YPLL), due to tobacco uses and life expectancy at birth (LEB), excluding mortality due to smoking. RESULTS: Smoking-attributable deaths represent 8.7% of all registered deaths in 1990. Ab high proportion of theses deaths belonged to ancient people. The smoking-attributable rate was 4.91 per 10,000 inhabitans (6.33 for males and 3.58 for females); YPLL rates, due to tobacco use was 2.98 per 1,000 inhabitans younger than 65 years (3.99 for men and 2.02 for women). CONCLUSIONS: Smoking-attributable mortality PYLL rates were higher than those rates observed for infectious and parasitical diseases, and for endocrinal and digestive system disorders. Due to tobacco use, men die more frequently and at a younger age than women. In the absence of tobacco use, the LEB increase would be notorious.

[Risk factors for unfavorable birth weight in areas surrounding Guadalajara, Mexico]. / Factores de riesgo del peso al nacer desfavorable en áreas periféricas de Guadalajara, México.

This study seeks to identify the incidence of unfavorable birth weight (UBW) -< 3000 grams, the factors associated with this condition, and the probability that a child has an UBW in the presence or absence of identified risk factors, in Tlaquepaque and Tonal , outlying areas of Greater Metropolitan Guadalajara, Mexico. A sample of live-born infants in 1991, children of mothers covered by the Mexican Institute of Social Security were selected from the study area; through multistage probabilistic sampling, random selection was made of Family Medical Units within the study areas, and of physicians' offices within those selected units; finally, all the liveborn infants in 1991 from these selected physicians' offices were studied: a total of 141 newborns were studied Mothers of the newborns chosen were interviewed; a questionnaire with different biomedical, socioeconomic, and demographic items was applied by social workers specially trained for the purpose. Logistic regression models were used lo estimate odds ratios (OR), with 95% confidence intervals (CI). The probability that a child would have UBW in the presence or absence of identified risk factors were also calculated. The results show that 22% of the infants studied were born weighing less than 3000 grams; four risk factors were statistically associated with UBW: mother's age of 35 or older (OR=18.47, CL 1.86-83.54); mother worked outside the home (OR= 3.14, C1:1.15-8.59); mother's pre-pregnancy low weight (OR= 5.04, CL1.04-24.47); and late detection of pregnancy (OR=2.64, CI: 1.02-6.84). In the presence of all the risk factors identified, there is a very high probability (0.97) that a child be born with birthweight less than 3000 g, and in the absence of these factors the probability is reduced substantially (0.04). The findings indicate the magnitude of the problem studied, but also the possibility of health services acting in a timely fashion, since the identified risk factors make it possible lo predict, with relative certainty, the birth of a child weighing less than 3000 g.

[Maternal factors associated with the duration of breast-feeding in peripheral areas of Guadalajara, Mexico]. / Factores maternos asociados a la duración de la lactancia en áreas periféricas de Guadalajara, México.

The aim of the present study is to determine the duration of breast-feeding by mothers covered by the Mexican Social Security Institute and living in Tlaquepaque and Tonalá, outlying areas of the city of Guadalajara, Mexico; to identify possible maternal factors associated with early weaning; and to consider the social importance of this phenomenon. A sample of live-born infants and their mothers were selected from the study area. The children had reached at least one month of age between May 1990 and April 1991. Through multistage probabilistic sampling, random selection was made of primary health care units within the study areas, of family physicians' offices within those units, and finally, of all children meeting the study criteria in each of those offices. After visits to 166 dwellings, 141 mothers were interviewed, or 91% of the projected sample size (155). A 33-item questionnaire was prepared for the interviews. The interviewers were social workers trained to do this work, which they carried out between June and July 1991. Logistic regression models were used to estimate the relative risk (RR) associated with each variable and the probability that the infant was weaned early because of the presence or absence of certain variables. To ensure valid results, several regression models were developed with a view to selecting the one that best fit the data. The population attributable risk (PAR) was also calculated. The findings indicate that few mothers breast-feed their children in these areas, since 34.8% of the children were breast-fed for less than one month. Three maternal risk factors were statistically associated with early weaning (p < 0.05): maternal age under 20 years (RR = 3.75; CI 95%: 1.53-9.19); single marital status (RR = 2.88; CI 95%: 1.08-7.69); and social class, i.e., the mother's belonging to a "non-worker" social group (RR = 2.72; CI 95%: 1.17-6.28). The probability of an infant being breast-fed for less than one month was 0.84 when the three maternal risk factors were present, and 0.15 when they were absent. The high estimated PAR reflects the high proportion of mothers who were under the age of 20 or did not belong to the working class. The results underscore the importance of reducing the effect of these risk factors so that breast-feeding can become more widely practiced in the population studied.

Maternal factors relating to breast-feeding duration in areas around Guadalajara, Mexico.

To investigate breast-feeding patterns and factors encouraging early weaning, a survey was conducted in Tonalá and Tlaquepaque, two suburbs within Guadalajara's metropolitan area, in 1991. For this purpose a multiphase probabilistic sample of infants born in these areas from May 1990 through April 1991 was selected. This was done by choosing at random primary health care units in the study areas, health posts associated with these units, and all infants meeting the above criteria at each selected post. A total of 166 homes was visited and interviews were conducted with 141 mothers (91% of the 155 predicted) in June and July 1991. These interviews made use of a 33-item questionnaire developed for the purpose; the interviewers were social workers previously trained in such activities. Logistic regression models were used to calculate the relative risk (RR) and probability of early weaning being associated with certain variables. To help ensure the validity of the results, several regression models were constructed for the purpose of selecting the one best fitting the data. In addition, the attributable population risk (APR) was calculated. The results indicate that failure to breast-feed and early weaning were prevalent in the study population, 34.8% of the study infants being breast-fed less than 1 month. Three risk factors were associated statistically (P < 0.05) with early weaning, these being maternal age < 20 years (RR = 3.75; 95% CI = 1.53-9.19), maternal marital status single (RR = 2.88; 95% CI = 1.08-7.69), and social status of the main family provider other than "worker"--i.e., employee, professional (RR = 2.72; 95% CI = 1.17-6.28). The likelihood that a study infant would have been breast-fed less than a month was 0.84 if the infant was exposed to all three of these identified risk factors and 0.15 if he or she was exposed to none of them. The high percentages of study mothers less then 20 years old and with a social status other than "worker" were reflected in high attributable population found for these variables. In general, the findings point up a need to reduce the influence of these risk factors and to prolong maternal breast-feeding in the study population.