Caffeine statistics

In 1990, Vatten et al.51 in Norway subsequently reviewed data on breast cancer risk from a cohort of 14,593 women with 152 cases of breast cancer during a follow up of 12 years on subjects who were between 35 and 51 years old at the beginning of the study and between 46 and 63 years at the end. They reported no overall statistically significant correlation between breast cancer and coffee consumption, but when body mass index was taken into account, lean women who consumed >5 cups per day had a lower risk than women who drank two cups or less. In obese women, however, there was a positive correlation between coffee intake and breast cancer. In a 1993 study, though, Folsom and associates52 failed to find an association between caffeine and postmenopausal breast cancer in 34,388 women in the Iowa Women s Health Study, with a median caffeine intake of 212 mg/day in women who developed breast cancer and 201 mg/day for women who did not and in Denmark, Ewertz53 studied... 

Higuchi and Lachman [122] pioneered the approach of improving drug stability by complexation. They showed that aromatic esters can be stabilized in aqueous solutions in the presence of xanthines such as caffeine. Thus, the half-lives of benzocaine, procaine hydrochloride, and tetracaine are increased by approximately two- to fivefold in the presence of 2.5% caffeine. This increase in stability is attributed to the formation of a less reactive complex between caffeine and the aromatic ester. Professor K. A. Connors has written a comprehensive textbook that describes methods for the measurement of binding constants for complex formation in solution—along with discussions of pertinent thermodynamics, modeling statistics,... 

Figure 7.55 shows a plot of over 2000 2%DOPC/dodecane Pe measurements (10-6 cm/s units), each representing at least three intra-plate replicates, vs. the estimated standard deviations, o(Pe). Over 200 different drug-like compounds were measured. The %CV (coefficient of variation 100 x a(Pe)/Pe) is about 10% near Pe 10 x 10 6 cm/s, and slightly increases for higher values of permeability, but rapidly increases for Pe< 0.1 x 10 6 cm/s, as shown in Table 7.21. These statistics accurately reflect the errors that should be expected in general. For some molecules, such as caffeine and metoprolol, %CV has been typically about 3-6%. 

The suggested derivative spectrophotometric method and PLS-1 were applied to determirration of caffeine in energy drirrks (Table 31.2). The assay results obtained by both methods were statistically compared at the 5% level. As shown in Table 31.2 there was no sigrrifrcant differences between the mean values and precisiorrs of two methods. 

Chronic use of large amounts of caffeine has been associated with an increased risk of cardiovascular disease. However, this finding is debated because statistically adjusting for other risk factors shows a minimized added risk for caffeine (Grobbee et al. 1990). Nonetheless, a lipid fraction of boiled coffee dose-dependently elevates cholesterol and low density lipoproteins, which is prevented by the filtered preparation of coffee (Pirich et al. 1993). Another potential influence on cardiovascular disease is an elevation of homocysteine levels, which also occurs in drinkers of filtered coffee (Nyg rd et al. 1997). Genotoxicity... 

Taste. Of the fundamental tastes, bitter is unique in showing human genetic differences in sensitivity. Six decades ago, it was reported tiiat phenylthiocarbamide (PTC) tasted extremely bitter to some individuals while being almost tasteless to others (45). Tlie ability to taste PTC was found to be a dominant genetic trait which occurs across gender, age and culture, with 70% of the American pulation carrying the dominant trait (46). Sensitivity to PTC and propylthiouracil (PROP) are correlated with sensitivities to otiier bitter tasting compounds, such as caffeine, saccharin (after-taste) and salts of i tassium cations and benzoate anions (47,48,49 0). However, in a reexamination of the sensitivity to NaQ and KQ, no differences were found between tasters and nontasters to non-PTC type compounds, and the statistical methods that showed differences were questioned (51). Individuals who do not respond to PTC are not necessarily insensitive to quinine, another intensely bitter compound (49,50,52). 

Effects of caffeine on the heart can be considerable. Rapid or irregular heartbeats can result from ingesting large amounts of caffeine. People at risk for heart attacks might be ill advised to drink coffee or indulge in other sources of caffeine. Caffeine intake exceeding the amount found in five or more cups of drip coffee a day results in a statistically increased risk of cardiac arrest. 

Although statistical comparisons were not performed on data other than the catecholamine levels, it was found that adrenaline levels were consistently higher 60-240 min after the 600-mg dose relative to placebo, and higher 60-150 min after the 600-mg dose relative to the 150-mg dose. Sleep latencies, sleepiness scores, and reaction times correlated with serum caffeine levels in the predicted direction, showing that caffeine improved alertness in a dose-dependent fashion. 

Figure 2.9 The figure is a binary image in which the caffeine domains created using particle statistics are visualized. Other sample components are set to zero, so only the caffeine domains are apparent.

Some studies have reported that a caffeine consumption of over 150 mg/day during pregnancy may be associated with a small but statistically significant increase in the risks of spontaneous abortion and low birth weight, although the authors could not rule out contributions of... 

Kiersch TA, Minic MR. The onset of action and the analgesic efficacy of Saridon (a propyphenazone/paracetamol/caffeine combination) in comparison with paracetamol, ibuprofen, aspirin and placebo (pooled statistical analysis). Curr Med Res Opin 2002 18(l) 18-25. 

We begin our review of caffeine by presenting the sources of caffeine and a brief history of its use. We then discuss current prevalence statistics. Following that we describe caffeine s pharmacological action, development of tolerance to and physical dependence on caffeine, and caffeine s acute and chronic effects. We conclude with a review of some therapeutic uses of caffeine and other major methylxanthine drugs. 

None of the widely quoted statistics embrace all those individuals dependent on drugs and medicaments, but always only those who attract attention because of crime, their lifestyle, or their social environment. In the case of benzodiazepines, appetite-suppressants and combinations of analgesics with caffeine, the low-dose dependence of the patient is often associated with social conditions, so that the problem is often seen in the context of the particular decade in which the abuse occurs. The same is true of the experimental drug-taker who discontinues his or her consumption after a short time and is not noticed. For this reason, exact national statistics on consumption behavior are difficult to obtain. Moreover, it is possible to detect trends, e.g. the appearance of new dependence phenomena, patterns of abuse, drug combinations or methods of application, and the analyst must arrange his work accordingly. 

Hawkins and Reifenrath made in vitro percutaneous absorption measurements using neat compoimds applied to skin and allowed to evaporate to air circulated over the apphed dose. For studies on benzo(a)pyrene absorption without sodium azide (NaNj), they foimd that mouse skin (6% of dose absorbed) was more permeable than human skin (1% of dose absorbed), which was more permeable than pig skin (0.6% of dose absorbed). In a similar study using 11 compounds [DDT, benzo(a)pyrene, fluocinonide acetonide, progesterone, hndane, testosterone, par-athion, diisopropyl fluorophosphonate, malathion, benzoic acid, and caffeine], they found that there was no statistically significant difference between human and pig skin. 

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