Leia atentamente os seguintes "Abstracts":
Coffee
use prior to myocardial infarction restudied: heavier intake may increase the
risk.
Klatsky AL, Friedman GD, Armstrong MA. Am J Epidemiol 1990 Sep;132(3):479-88
Because
of conflicting evidence about the relation of coffee use to coronary artery
disease, the authors conducted a new cohort study of hospitalizations among
101,774 white persons and black persons admitted to Kaiser Permanente hospitals
in northern California in 1978-1986. In analyses controlled for eight covariates,
use of coffee was associated with higher risk of myocardial infarction (p =
0.0002). Compared with nondrinkers of coffee, the following relative risks (RRs)
were found: at 1-3 cups/day, RR = 1.14 (95% confidence interval (CI) 0.91-1.42);
at 4-6 cups/day, RR = 1.42 (CI 1.10-1.84), p = 0.007; and at greater than 6
cups/day, RR = 1.41 (CI 1.00-1.99), p = 0.05. The relation remained significant
when also controlled for blood cholesterol, blood glucose, blood pressure, and
adiposity, singly or combined. Tea use was unrelated to myocardial infarction;
neither coffee nor tea was related to other coronary diagnoses. Although causality
remains unestablished and uncertainty remains, the authors conclude that 1)
these data suggest a weak independent relation of coffee use to acute myocardial
infarction, not mediated by an effect on blood cholesterol; and 2) persons at
risk of myocardial infarction should consider limitation of coffee intake to
less than 4 cups/day.
Coffee
drinking and nonfatal myocardial infarction in men under 55 years of age.
Rosenberg L, Palmer JR, Kelly JP, Kaufman DW, Shapiro S. Am J Epidemiol 1988
Sep;128(3):570-8
The relation of coffee consumption to the risk of nonfatal first myocardial infarction in men under 55 years of age was assessed in a hospital-based case-control study conducted from 1980 to 1983 in hospitals in Massachusetts, Rhode Island, Connecticut, and New York: 1,873 men with first nonfatal myocardial infarctions were compared with 1,161 controls admitted for conditions unrelated to coffee ingestion. After allowance for major risk factors for myocardial infarction, the relative risk estimate for recent consumption of caffeine-containing coffee increased with increasing level of daily intake, from 1.4 for one to two cups per day to 1.6 for three to four cups, 1.8 for five to nine cups, and 2.9 for greater than or equal to 10 cups, relative to consumption of no coffee (p less than 0.001 for trend). The association was apparent in each age group and in both smokers and nonsmokers. For those who drank decaffeinated coffee only, on the basis of small numbers, there was a suggestion of an increased risk among men who had consumed at least five cups daily for less than five years but not among those who had drunk this amount for at least five years; whether the apparent association among the shorter-term drinkers was due to previous consumption of caffeine-containing coffee could not be determined. The findings suggest that caffeine-containing coffee increases the risk of myocardial infarction and that men who drink at least five cups daily may increase their risk by about twofold or more.
A
meta-analysis of coffee, myocardial infarction, and coronary death.
Greenland
S. Epidemiology 1993 Jul;4(4):366-74
This paper presents a meta-analysis of 22 studies of coffee use and myocardial infarction or coronary death. In the eight case-control studies, a fairly homogeneous increased risk was found among coffee users (geometric mean rate ratio of 1.42 for 5 cups per day vs none, with 95% confidence limits of 1.30, 1.55, homogeneity P-value of 0.89). The 14 cohort studies tended to exhibit lower but very heterogeneous rate ratios, with a trend toward larger rate ratios in studies with longer follow-up periods and later publication dates (geometric mean rate ratio of 0.92 for the five cohort studies published up to 1981, 1.27 for the nine cohort studies published in 1986 or later; overall homogeneity P-value of 0.0008). The evidence thus remains ambiguous regarding both the existence and size of a coffee effect, and although a rate ratio of over 1.5 for 5 cups per day appears unlikely, stronger effects for 10-cup-per-day drinkers cannot be ruled out.
Nestes três estudos tenta responder-se a uma mesma questão utilizando três metodologias diferentes.
1.Indique a questão
que estes estudos pretendem responder.
2. Identifique
as diferentes metodologias usadas em cada um dos três estudos.
3. Aponte vantagens e desvantagens destes três tipos de estudos.