11 de Outubro, 2009
A níveis de colesterol total entre 211 e 250 mg/dl está associada menor mortalidade total numa população de 482,472 homens coreanos, ou como a chamada hipercolesterolémia (LDL mauzão elevado?) é um “problema” ficcional da medicina moderna
Quando não se consegue aceitar que a chamada hipercolesterolémia, algo que eu nem consigo entender bem o que é, não representa qualquer problema para o ser humano, bem pelo contrário, é necessariamente uma ficção pois à mesma está associada MENOR MORTALIDADE TOTAL, resolve-se o "problema" chamando-lhe paradoxo! Portanto, mais um paradoxo a juntar aos outros de quem não consegue aceitar a realidade da ciência. É compreensível que estes factos sejam pouco divulgados, porque não convém nada às indústrias estatineira e margarineira, apostadas em nos baixar o colesterol à força, que se entenda o embuste que é esta hipótese lipídica. Na realidade, níveis aumentados de LDL provavelmente nada têm a haver com doença cardiovascular, pois o facto é que doentes cardiovasculares, fora da influência de estatinas, até estão deficientes em LDL (nos EUA, por regra apresentam média de 120 mg/dl, ou mesmo 116.9 mg/dl - Nota: este último valor foi corrigido para "LDL sem estatinas") face à população em geral (valores médios de 127 mg/dl). E o "sucesso" das estatinas, poderá nada ter a haver com redução de LDL? Porventura, será a aterosclerose antes uma doença primordialmente inflamatória, e não "acumulatória" de lípidos entupidores de artérias? Sim, eu sei, nada disto encaixa na ideia (ou será antes mito urbano?!) de que doença cardiovascular é causada por LDL mauzão em excesso, pois não? Mas há muita ciência e epidemiologia em suporte destas outras hipóteses que aqui se referem. A respeito de níveis de colesterol total e de mortalidade, veja-se também o meu artigo Lowest mortality observed when total cholesterol (t-C) is 200-240 mg/dl, low t-C linked to more infectious and parasitic diseases and also low t-C maybe associated with higher CHD.
To evaluate the relation between low cholesterol level and mortality, the authors followed 482,472 Korean men aged 30-65 years from 1990 to 1996 after a baseline health examination. The mean cholesterol level of the men was 189.1 mg/100 ml at the baseline measurement. There were 7,894 deaths during the follow-up period. A low cholesterol level ( or =252 mg/100 ml). There were various relations between cholesterol level and cancer mortality by site. Mortality from liver and colon cancer was significantly associated with a very low cholesterol level (
BACKGROUND: Hypercholesterolemia is a risk factor for coronary artery disease, yet is associated with lower risk of adverse outcomes in patients with acute coronary syndromes (ACS). HYPOTHESIS: We explored this paradox in 84,429 patients with non-ST-segment elevation ACS in the Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes with Early Implementation of the American College of Cardiology/American Heart Association Guidelines registry. METHODS: We examined the association between a history of hypercholesterolemia and in-hospital mortality after adjusting for clinical covariates. After excluding patients with previously diagnosed hypercholesterolemia, we repeated the analysis, examining the association between newly diagnosed hypercholesterolemia (in-hospital low-density lipoprotein cholesterol [LDL-C] > or = 100 mg/dL) and mortality. RESULTS: A history of hypercholesterolemia was associated with lower in-hospital mortality (unadjusted odds ratio [OR]: 0.58; 95% confidence interval [CI]: 0.55, 0.62). This protective association persisted after adjusting for baseline characteristics (OR: 0.71; 95% CI: 0.66, 0.76) and prior statin use (OR: 0.74; 95% CI: 0.68, 0.80). Among 22,711 patients with no history of hypercholesterolemia, 12,809 had a new in-hospital diagnosis of hypercholesterolemia. Unadjusted mortality in these patients was lower than among those with normal LDL levels (OR: 0.58; 95% CI: 0.50, 0.67); however, this difference was not significant after multivariable adjustment (OR: 0.86; 95% CI: 0.73, 1.01). CONCLUSIONS: The association of hypercholesterolemia with better outcomes highlights a major challenge in observational analyses. Our results suggest this paradox may result from confounding due to other clinical characteristics, impact of statin treatment, and perhaps most importantly, the fact that previously diagnosed hypercholesterolemia is a marker for patients with more prior medical contact.
Lowering cholesterol concentrations and mortality: a quantitative review of primary prevention trials. (pdf)
OBJECTIVE–To determine the effects of lowering cholesterol concentrations on total and cause specific mortality in randomised primary prevention trials. DESIGN–Qualitative (meta-analytic) evaluation of total mortality from coronary heart disease, cancer, and causes not related to illness in six primary prevention trials of cholesterol reduction (mean duration of treatment 4.8 years). PATIENTS–24,847 Male participants; mean age 47.5 years. MAIN OUTCOME MEASURES–Total and cause specific mortalities. RESULTS–Follow up periods totalled 119,000 person years, during which 1147 deaths occurred. Mortality from coronary heart disease tended to be lower in men receiving interventions to reduce cholesterol concentrations compared with mortality in control subjects (p = 0.06), although total mortality was not affected by treatment. No consistent relation was found between reduction of cholesterol concentrations and mortality from cancer, but there was a significant increase in deaths not related to illness (deaths from accidents, suicide, or violence) in groups receiving treatment to lower cholesterol concentrations relative to controls (p = 0.004). When drug trials were analysed separately the treatment was found to reduce mortality from coronary heart disease significantly (p = 0.04). CONCLUSIONS–The association between reduction of cholesterol concentrations and deaths not related to illness warrants further investigation. Additionally, the failure of cholesterol lowering to affect overall survival justifies a more cautious appraisal of the probable benefits of reducing cholesterol concentrations in the general population.
Statin therapy, lipid levels, C-reactive protein and the survival of patients with angiographically severe coronary artery disease. (pdf)
OBJECTIVES: The joint predictive value of lipid and C-reactive protein (CRP) levels, as well as a possible interaction between statin therapy and CRP, were evaluated for survival after angiographic diagnosis of coronary artery disease (CAD). BACKGROUND: Hyperlipidemia increases risk of CAD and myocardial infarction. For first myocardial infarction, the combination of lipid and CRP levels may be prognostically more powerful. Although lipid levels are often measured at angiography to guide therapy, their prognostic value is unclear. METHODS: Blood samples were collected from a prospective cohort of 985 patients diagnosed angiographically with severe CAD (stenosis > or =70%) and tested for total cholesterol (TC), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and CRP levels. Key risk factors, including initiation of statin therapy, were recorded, and subjects were followed for an average of 3.0 years (range: 1.8 to 4.3 years) to assess survival. RESULTS: Mortality was confirmed for 109 subjects (11%). In multiple variable Cox regression, levels of TC, LDL, HDL and the TC:HDL ratio did not predict survival, but statin therapy was protective (adjusted hazard ratio [HR] = 0.49, p = 0.04). C-reactive protein levels, age, left ventricular ejection fraction and diabetes were also independently predictive. Statins primarily benefited subjects with elevated CRP by eliminating the increased mortality across increasing CRP tertiles (statins: HR = 0.97 per tertile, p-trend = 0.94; no statins: HR = 1.8 per tertile, p-trend
BACKGROUND: Lipid levels among contemporary patients hospitalized with coronary artery disease (CAD) have not been well studied. This study aimed to analyze admission lipid levels in a broad contemporary population of patients hospitalized with CAD. METHODS: The Get With The Guidelines database was analyzed for CAD hospitalizations from 2000 to 2006 with documented lipid levels in the first 24 hours of admission. Patients were divided into low-density lipoprotein cholesterol (LDL), high-density lipoprotein cholesterol (HDL), and triglyceride categories. Factors associated with LDL and HDL levels were assessed along with temporal trends. RESULTS: Of 231,986 hospitalizations from 541 hospitals, admission lipid levels were documented in 136,905 (59.0%). Mean lipid levels were LDL 104.9 +/- 39.8, HDL 39.7 +/- 13.2, and triglyceride 161 +/- 128 mg/dL. Low-density lipoprotein cholesterol or =60 mg/dL) in only 1.4%. High-density lipoprotein cholesterol was or =60 mg/dL. These findings may provide further support for recent guideline revisions with even lower LDL goals and for developing effective treatments to raise HDL.
CONTEXT: Serum total and low-density lipoprotein (LDL) cholesterol contribute significantly to atherosclerosis and its clinical sequelae. Previous analyses of data from the National Health and Nutrition Examination Surveys (NHANES) showed that mean levels of total cholesterol of US adults had declined from 1960-1962 to 1988-1994, and mean levels of LDL cholesterol (available beginning in 1976) had declined between 1976-1980 and 1988-1994. OBJECTIVE: To examine trends in serum lipid levels among US adults between 1960 and 2002, with a particular focus on changes since the 1988-1994 NHANES survey. DESIGN, SETTING, AND PARTICIPANTS: Blood lipid measurements taken from 6098 to 15 719 adults who were examined in 5 distinct cross-sectional surveys of the US population during 1960-1962, 1971-1974, 1976-1980, 1988-1994, and 1999-2002. MAIN OUTCOME MEASURES: Mean serum total cholesterol, LDL cholesterol, high-density lipoprotein (HDL) cholesterol, and geometric mean serum triglyceride levels, and the percentage of adults with a serum total cholesterol level of at least 240 mg/dL (> or =6.22 mmol/L). RESULTS: Between 1988-1994 and 1999-2002, total serum cholesterol level of adults aged 20 years or older decreased from 206 mg/dL (5.34 mmol/L) to 203 mg/dL (5.26 mmol/L) (P=.009) and LDL cholesterol levels decreased from 129 mg/dL (3.34 mmol/L) to 123 mg/dL (3.19 mmol/L) (P<.001 greater and significant decreases were observed in men years or older women older. the percentage of adults with a total cholesterol level at least mg> or =6.22 mmol/L) decreased from 20% during 1988-1994 to 17% during 1999-2002 (P<.001 there was no change in mean hdl cholesterol levels and a nonsignificant increase geometric serum triglyceride .06 conclusions: the decrease total level observed during ldl has continued men to years women years. target value of more than us adults with at least mg> or =6.22 mmol/L), an objective of Healthy People 2010, has been attained. The increase in the proportion of adults using lipid-lowering medication, particularly in older age groups, likely contributed to the decreases in total and LDL cholesterol levels observed. The increased prevalence of obesity in the US population may have contributed to the increase in mean serum triglyceride levels.