Coronary bypass surgery in stable angina pectoris. A randomized study of the effects on morbidity, mortality and employment

The effects of coronary bypass surgery on morbidity, mortality and employment were assessed in a randomized prospective 5-year study. Exercise tolerance showed an immediate, striking improvement, which was maintained throughout the follow-up period. Corresponding patients treated with medical therapy showed no change. More than 40 percent of patients in the surgical group were free from symptoms over the five years. The annual mortality of the surgical patients was 0.8 percent as compared with 4.0 percent in the medical patients (p less than 0.05). The annual mortality of the intensively treated medical patients with multivessel disease was not significantly higher than the 3.1 percent for a group of patients with single-vessel disease followed concomitantly. The rate of work at 5 years after bypass surgery was 47 percent as compared with only 18 percent in the randomized medically treated group (p less than 0.01). It is concluded that coronary bypass surgery reduces morbidity and mortality and improves employment.

A sustained effect of coronary bypass surgery in stable angina pectoris

One hundred patients with angina pectoris were randomly allocated for medical therapy and bypass surgery in groups of 50 patients each. The effect of the respective therapies was assessed by annual exercise testing for up to five years. The surgical group was also studied by postoperative coronary angiograms at three weeks, one year and five years after the operation. The medical group was subjected to repeated coronary angiography five years after randomization. All of the variables depicting exercise tolerance were significantly improved in the surgical group but remained largely at the initial level in the medical group. A subgroup analysis of the surgical series revealed that the sustained improvement was largely confined to the completely revascularized subset of patients. The slowly increasing use of beta blocking compounds in the surgical group also contributed to the favourable results for bypass surgery.

Remnant-like lipoprotein particle cholesterol concentration and progression of coronary and vein-graft atherosclerosis in response to gemfibrozil treatment

Remnant lipoproteins such as chylomicron and very low density lipoprotein (VLDL) remnants have been implicated in the progression of coronary atherosclerosis. Recently, a novel method for the determination of the remnant-like lipoprotein particle cholesterol (RLP-C) concentration was developed based on immunoaffinity-separation of plasma. The compositional characteristics of RLP are strikingly similar to those of postprandially modified VLDL. In addition, the method also detects chylomicron remnants. We investigated the relationship between the plasma RLP-C concentration and the angiographic outcome of the 2-year, randomised, placebo-controlled Lipid Coronary Angiography Trial (LOCAT), which used gemfibrozil as lipid lowering agent. The RLP-C response to gemfibrozil treatment has not been described before. Gemfibrozil reduced the median RLP-C concentration by 34%. The on-treatment RLP-C concentration was significantly associated with the progression of the minimum lumen diameter (MLD) (P<0.004). The plasma levels of RLP-C as well as the change in response to treatment was closely associated with plasma triglycerides and the association between on-treatment RLP-C concentration and progression of MLD was not independent of plasma triglycerides. A significant relation was seen between RLP-C and the occurrence of new lesions in vein grafts. Subjects with one new lesion had an approximately 25% higher on-treatment RLP-C concentration and the four patients showing two new lesions had a 100% higher RLP-C concentration than patients without vein graft stenosis. A total of 19 out of 23 subjects having one new lesion, and all four patients showing two new lesions, were assigned to the placebo group. We conclude that the RLP-C concentration, which is likely to reflect the plasma cholesterol contained in postprandially modified VLDL and chylomicron remnants, is strongly associated with angiographically verified progression of focal coronary atherosclerosis, and that lowering of RLPs prevents vein graft stenosis.

Fibrinolytic proteins and progression of coronary artery disease in relation to gemfibrozil therapy

Impaired fibrinolytic function, mainly due to increased plasma plasminogen activator inhibitor-1 (PAI-1) activity, is common in patients with manifest coronary artery disease (CAD) and a predictor of recurrent cardiovascular events. We investigated the relationships of plasma tissue-type plasminogen activator (tPA) and PAI-1 antigen levels, plasma PAI-1 activity and PAI 4/5-guanosine (4G/5G) genotype to CAD progression in 203 middle-aged men participating in the Lopid Coronary Angiography Trial (LOCAT). A higher tPA antigen concentration, whether baseline or on-trial, was associated with a more severe global angiographic response (p < 0.05), an association mainly accounted for by progression of diffuse lesions in graft-affected segments (change in per-patient means of average diameters of segments haemodynamically related to bypass grafts). Plasma PAI-1 activity and mass concentration and 4G/5G PAI-1 genotype were unrelated to angiographic outcome measurements. tPA and PAI-1 antigen increased significantly in the gemfibrozil group (+11.3% and + 16.4%, respectively, p < 0.001), whereas there was no treatment effect on PAI-1 activity (median change 0.0%). It is concluded that fibrinolytic function does not substantially influence progression of CAD as assessed by angiography in middle-aged men. Furthermore, pronounced long-term lowering of serum triglycerides by gemfibrozil treatment does not significantly affect the plasma PAI-1 activity level but increases the plasma tPA and PAI-1 antigen concentrations.

Heart rate variability and progression of coronary atherosclerosis

Low heart rate (HR) variability is associated with increased risk of cardiovascular morbidity and mortality, but the causes and mechanisms of this association are not well known. This prospective study was designed to test the hypothesis that reduced HR variability is related to progression of coronary atherosclerosis. Average HR and HR variability were analyzed in 12-hour ambulatory ECG recordings from 265 qualified patients participating in a multicenter study to evaluate the angiographic progression of coronary artery disease in patients with prior coronary artery bypass surgery and low high-density lipoprotein cholesterol concentrations (<1.1 mmol/L). Participants were randomized to receive a placebo or gemfibrozil therapy. The progression of coronary atherosclerosis was estimated by quantitative, computer-assisted analysis of coronary artery stenoses from the baseline angiograms and from repeated angiograms performed an average of 32 months later. The progression of focal coronary atherosclerosis of the patients randomized to placebo therapy was more marked in the tertile with the lowest standard deviation of all normal to normal R-R intervals (SDNN, 74+/-13 ms; mean decrease in the per-patient minimum luminal diameter -0.17 mm; 95% confidence interval [CI], -0.23 to -0.12 mm) than in the middle tertile (SDNN, 107+/-7 ms; mean decrease -0.05 mm; 95% CI, -0.08 to -0.01 mm) or highest tertile (SDNN, 145+/-25 ms; mean change 0.01 mm; 95% CI, -0. 04 to 0.02 mm) (P<0.001 between the tertiles). This association was abolished by gemfibrozil. SDNN was lower (P<0.001) and minimum HR was faster (P<0.01) in the patients with marked progression than in those with regression of focal coronary atherosclerosis. In multiple regression analysis including HR variability, minimum HR, demographic and clinical variables, smoking, blood pressure, glucose, lipid measurements and lipid-modifying therapy, progression of focal coronary atherosclerosis was independently predicted by the SDNN (beta=0.24; P=0.0001). Low HR variability analyzed from ambulatory ECG predicts rapid progression of coronary artery disease. HR variability provided information on progression of focal coronary atherosclerosis beyond that obtained by traditional risk markers of atherosclerosis.

Associations between lipoproteins and the progression of coronary and vein-graft atherosclerosis in a controlled trial with gemfibrozil in men with low baseline levels of HDL cholesterol

BACKGROUND

Lipid-lowering secondary-prevention trials of coronary artery disease (CAD) have implicated triglyceride-rich lipoproteins as the main determinants of angiographic progression after elevated LDL cholesterol levels have been lowered with therapy. The present study focuses on the lipoprotein determinants of angiographic CAD progression in men with low HDL cholesterol concentration as their main baseline lipid abnormality who underwent 32 months of randomized therapy with gemfibrozil or placebo.

METHODS AND RESULTS

Men who had undergone coronary bypass surgery (n=372) completed a randomized, placebo-controlled study with gemfibrozil 1200 mg/d. They were selected primarily for HDL cholesterol levels that corresponded to the lowest third for middle-aged men. Average baseline lipid and lipoprotein levels were serum triglyceride, 1.60; serum cholesterol, 5.17; ultracentrifugally separated LDL cholesterol, 3.43; HDL2 cholesterol, 0.41; and HDL3 cholesterol, 0. 61 mmol/L. In the gemfibrozil group, these levels were reduced on average by 40%, 9%, and 6% or increased by 5% and 9%, respectively. On-trial IDL and LDL triglyceride and cholesterol levels significantly predicted global angiographic progression, taking into account changes in native segments and in bypass grafts. HDL3 but not HDL2 cholesterol concentration was associated with protection against progression, especially focal disease in native coronary lesions. VLDL was the lipoprotein most predictive of new lesions in vein grafts; IDL was also significantly related.

CONCLUSIONS

This study expands the previous evidence of the triglyceride-rich lipoproteins, especially IDL, as predictors of angiographic progression of CAD but does not negate the significance of mildly elevated LDL levels. Of the HDL subfractions, only HDL3 was protective in this group of men selected for their low initial HDL levels.

The 5A/6A polymorphism in the promoter of the stromelysin-1 (MMP-3) gene predicts progression of angiographically determined coronary artery disease in men in the LOCAT gemfibrozil study. Lopid Coronary Angiography Trial

The relationship between the 5A/6A stromelysin-1 promoter polymorphism and progression of angiographically determined coronary artery disease (CAD) has been examined in men treated for 32 months with gemfibrozil or placebo in the Lopid Coronary Angiography Trial (LOCAT). The frequency of the 5A allele was 0.40 (95%, CI, 0.36-0.43), and in the sample as a whole 12% of the men were homozygous for the 5A allele. In the placebo group, diffuse progression of disease was, on average, completely prevented in men with the genotype 5A/5A as measured by a 0.30% increase in mean average diameter of the coronary artery segments (ADS), compared with a mean 1.79% decrease in the combined group with the genotype 5A6A or 6A6A (mean +/- S.E.M., +0.007 +/- 0.020 mm vs. -0.043 +/- 0.0.08 mm, P = 0.03). A similar relationship with genotype was seen for disease progression determined by the mean minimal luminal diameter (MLD); with the 5A5A group decreasing by an average of 1.72% compared with 5.54% in the 5A/6A plus 6A/6A group (-0.029 +/- 0.034 mm vs. -0.102 +/- 0.013 mm, P = 0.06). In the gemfibrozil-treated group, the effect on disease progression associated with the 5A/6A alleles was of a similar pattern as in the placebo group, but the effect was less marked and was not statistically significant. This study confirms the previously reported beneficial effect on disease progression associated with the 5A allele and raises the possibility that patients with CAD who are homozygous for the 6A allele, and who represent 25-30% of the population, may be at particular risk of rapid progression of disease and may require particularly aggressive lipid lowering therapy to prevent disease progression.

Association of variation in hepatic lipase activity with promoter variation in the hepatic lipase gene. The LOCAT Study Invsestigators

The associations between six genetic polymorphisms in the hepatic lipase (HL) gene (LIPC) and variation in postheparin HL activity and fasting serum lipoproteins were evaluated in 395 male Finnish coronary heart disease patients with HDL cholesterol concentrations </= 1.1 mmol/liter. The LIPC promoter polymorphism at position -514 was highly significantly associated with variation in HL activity (P = 0.0000008), with mean activities of 20.4, 17.5, and 13.2 mumol free fatty acid/ml per hour in subjects having C/C, C/T, and T/T genotypes, respectively. Furthermore, the triglyceride content of low density lipoprotein, intermediate density lipoprotein and HDL, and the cholesterol content of intermediate density lipoprotein were found to be associated with variation at LIPC position -514. However, there was no association of this polymorphism with coronary heart disease. These data suggest that the LIPC promoter variation is likely to be the basis for variation in HL activity, which underlies the variation in serum lipoprotein phenotypes in this sample.

Prevention of the angiographic progression of coronary and vein-graft atherosclerosis by gemfibrozil after coronary bypass surgery in men with low levels of HDL cholesterol. Lopid Coronary Angiography Trial (LOCAT) Study Group

BACKGROUND

Studies have shown that treatment of hyperlipidemia, especially lowering of plasma LDL levels, retards the progression of coronary atherosclerosis and prevents clinical cardiovascular events. No such studies have focused on subjects with low levels of HDL cholesterol.

METHODS AND RESULTS

We randomly assigned 395 post-coronary bypass men, who had an HDL cholesterol concentration < or = 1.1 mmol/L and LDL cholesterol < or = 4.5 mmol/L, to receive gemfibrozil 1200 mg/d or placebo. Coronary angiography was performed at baseline and after, on average, 32 months of therapy. Changes in coronary dimensions were assessed by computer-assisted analysis. Average on-trial serum triglyceride concentrations were 1.69+/-0.68 and 1.02+/-0.37, total cholesterol 5.48+/-0.68 and 4.83+/-0.63, LDL cholesterol 3.84+/-0.59 and 3.39+/-0.56, and HDL cholesterol 0.88+/-0.15 and 0.98+/-0.17 mmol/L in the placebo and gemfibrozil groups, respectively (mean+/-SD, each P<.001). The change in per-patient means of average diameters of native coronary segments was -0.04+/-0.11 mm in the placebo group and -0.01+/-0.10 mm in the gemfibrozil group (P=.009). The equivalent changes in minimum luminal diameters of stenoses were -0.09+/-0.18 and -0.04+/-0.15 mm, respectively (P=.002). A similar, albeit nonsignificant, trend toward treatment benefit was found in the predefined primary study end point, segments unaffected by grafts and those distal to graft insertions. In aortocoronary bypass grafts, 23 subjects (14%) assigned to placebo had new lesions in the follow-up angiogram, compared with 4 subjects (2%) assigned to gemfibrozil (P<.001).

CONCLUSIONS

Gemfibrozil therapy retarded the progression of coronary atherosclerosis and the formation of bypass-graft lesions after coronary bypass surgery in men with low HDL cholesterol as their main lipid abnormality.

A study to determine the response of coronary atherosclerosis to raising low high density lipoprotein cholesterol with a fibric-acid derivative in men after coronary bypass surgery. The rationale, design, and baseline characteristics of the LOCAT Study. Lopid Coronary Angiography Trial

Several clinical trials have shown that reducing serum cholesterol levels retards the progression of coronary atherosclerosis assessed by serial angiography. By contrast, as yet no studies have addressed the impact of increasing high density lipoprotein (HDL) cholesterol levels on progression of coronary artery disease (CAD). As HDL cholesterol is inversely related to the risk of CAD, we hypothesize that an intervention that raises low HDL cholesterol concentrations may have a beneficial effect on the course of CAD. Lopid Coronary Angiography Trial (LOCAT) was designed to test this hypothesis. Three hundred and ninety-five men, aged < or = 70 years, all of whom had previously undergone coronary bypass surgery, were randomly assigned to receive either slow-release gemfibrozil, 1200 mg once daily, or a matching placebo for on average 2 1/2 years. The lipid inclusion criteria were HDL cholesterol concentration < or = 1.1 mmol/L, low density lipoprotein (LDL) cholesterol < or = 4.5 mmol/L, and serum triglyceride < or = 4.0 mmol/L. Subjects were not accepted if they had manifest diabetes, body mass index > 30 kg/m2, uncontrolled hypertension, or if they were regular smokers. All randomized subjects underwent baseline coronary angiography, which will be repeated at the end of the study. The angiograms will be analyzed using the Cardiovascular Measurement System, a validated computer-assisted image-analysis and quantitation package. The primary endpoints are the changes in the per-patient mean of 1) the average diameter of evaluable native coronary segments, and 2) the minimal luminal diameter of evaluable stenoses, and 3) the appearance of new lesions. Extensive lipoprotein and other metabolic studies and analyses of genetic polymorphisms are carried out to study the determinants of CAD progression. At baseline, the study subjects were 59.1 +/- 6.8 (mean +/- standard deviation) years old, had a body mass index 26.4 +/- 2.2 kg/m2, and serum triglyceride, serum cholesterol, HDL cholesterol, and LDL cholesterol concentrations 1.64 +/- 0.64, 5.17 +/- 0.64, 0.82 +/- 0.14, and 3.61 +/- 0.53 mmol/L, respectively.

The Gln-Arg191 polymorphism of the human paraoxonase gene (HUMPONA) is not associated with the risk of coronary artery disease in Finns

The human paraoxonase gene (HUMPONA) is codominantly expressed as alleles A and G. The A allele codes for glutamine (A genotype) and the G allele for arginine (B genotype) at position 191 of the paraoxonase enzyme. This genetic polymorphism has been suggested to be associated with the predisposition to coronary artery disease (CAD). We investigated the frequency of paraoxonase A and G alleles in 380 well-characterized CAD patients and in 169 controls. The most common genotype in both the patients with CAD (211/380) and in healthy Finnish individuals (87/169) was AA (Gln/Gln). The heterozygous AM (Gln/Arg) genotype was present in 140 of the patients and in 75 controls. The frequency of the A allele was 0.74 in both patients and controls. The genotype distribution between the two groups did not differ (P = 0.12, chi2 test). The genotype distributions were also similar to those reported earlier in other caucasoid populations. In conclusion, we found no association between the Gln-Arg 191 polymorphism of the human paraoxonase gene and coronary artery disease in Finns.

Antihypertensive therapy in dyslipidemic men. Effects on coronary heart disease incidence and total mortality

To investigate the influence of antihypertensive therapy and the success of blood pressure control on coronary heart disease incidence and total mortality, we studied dyslipidemic middle-aged men participating in the placebo arm of the Helsinki Heart Study, a randomized coronary primary prevention trial with gemfibrozil. Based on blood pressure level and the presence of antihypertensive therapy at study entry, the participants were classified into four categories. Relative risks of coronary heart disease (nonfatal myocardial infarction or cardiac death) and total mortality during the 5-year trial period were calculated using Cox proportional hazards models. With subjects who were not using antihypertensive drugs and who had normal blood pressure (category I) as reference, the relative risks of coronary heart disease during the trial period were 2.1 (95% confidence interval [CI], 1.3 to 3.3) in untreated hypertensive subjects (category II), 0.9 (95% CI, 0.2 to 3.8) in subjects with successful antihypertensive therapy (category III), and 2.0 (95% CI, 1.0 to 4.1) in subjects who remained hypertensive despite drug therapy (category IV). The relative risks of death were 1.9 (95% CI, 0.9 to 3.9) in category II and 1.0 (95% CI, 0.1 to 7.3) in category III; in category IV subjects, those with unsuccessful antihypertensive therapy, the relative risk was 4.4 (95% CI, 2.0 to 9.6). The excess mortality in this category was due to cardiovascular causes and was clustered in subjects with multiple drug therapy for hypertension control. We conclude that successful antihypertensive therapy in dyslipidemic men reduced coronary heart disease incidence despite its adverse effects on high-density lipoprotein cholesterol and triglycerides.(ABSTRACT TRUNCATED AT 250 WORDS)

Accuracy and precision of quantitative arteriography in the evaluation of coronary artery disease after coronary bypass surgery. A validation study

Computer-assisted quantitative coronary arteriography (QCA) has gained widespread acceptance in assessing changes in coronary dimensions over time, but little is known about the utility of QCA in patients having undergone coronary bypass surgery. As a validation study, we analyzed the accuracy and precision of QCA in a subset of the baseline angiograms of a clinical trial in 395 post-bypass men with low HDL cholesterol concentrations who have been randomized to receive double-blind gemfibrozil or placebo for 2 1/2 years. Based on repeat measurements of the same cineframe, the average diameter of a segment (ADS) had a mean coefficient of variation (CV) of 3.1%. The mean CVs of the minimum luminal diameter (MLD), percent diameter stenosis (PDS) and stenotic flow reserve of an obstruction were 8.6, 10.2 and 9.8%, respectively, but the area of the atherosclerotic plaque had an unacceptably high CV, 24.0%. When the measurements from two contrast injections into a native coronary artery during the same angiographic session were compared, precision (standard deviation of the differences) was 0.198 mm for ADS, 0.192 mm for MLD, and 7.37% for PDS. Variability was not substantially reduced when measurements from 3 or 5 consecutive cineframes were averaged. Comparable repeatability was found when venous bypass grafts were imaged twice, whether the grafts themselves or the grafted native vessels were analyzed. We conclude that QCA has an acceptable accuracy and precision in analyzing coronary dimensions in bypass-grafted patients. A change of 0.40 mm in ADS and MLD, and 20% in PDS represent true progression or regression of coronary atherosclerosis with more than 95% confidence.

Serum ferritin and ceruloplasmin as coronary risk factors

Iron and copper catalyze lipid peroxidation in vitro, and recent epidemiological data suggest that these metal ions might also be involved in human coronary heart disease. We tested the hypothesis by investigating whether the storage proteins ferritin and ceruloplasmin were coronary risk factors. A nested case-control study was set up in middle-aged dyslipidaemic participants of the Helsinki Heart Study: a placebo-controlled coronary primary prevention trial with gemfibrozil. Of the 140 subjects with cardiac end-points (non-fatal myocardial infarction or cardiac death) 136 were matched with controls for geographical area and drug treatment (gemfibrozil-placebo). Frozen baseline serum samples were used in the analyses of ferritin and ceruloplasmin. Using logistic regression analyses no increment in coronary risk was detected with increasing ferritin levels (P = 0.8 for trend). Ceruloplasmin was higher 349 +/- 86 vs 317 +/- 77 mg.l-1 (P < 0.001) in cases than in controls and the risk in the highest tertile was two-fold (odds ratio 2.1; 95% CI 1.1-4.2) compared to the lowest (P < 0.005 for trend). The risk of high ceruloplasmin was influenced by lipoprotein cholesterol concentrations, with an odds ratio of 2.4 (95% CI 1.3-4.4) in subjects with high low density lipoprotein cholesterol and of 11.3 (95% CI 2.5-52.2) in subjects with low high density lipoprotein cholesterol. It was concluded that ferritin was not associated with coronary heart disease in dyslipidaemic, middle-aged men, while there was a continuous and graded increment in coronary risk with elevating ceruloplasmin level.

Long-term efficacy and safety of pimobendan in moderate heart failure. A double-blind parallel 6-month comparison with enalapril. The Pimobendan-Enalapril Study Group

In view of growing scepticism as to the efficacy and safety of agents with predominant phosphodiesterase inhibiting properties in heart failure, the clinical efficacy and safety of pimobendan, a calcium-sensitizing and partially phosphodiesterase-inhibiting compound, was compared with enalapril in 242 patients with mild to moderate heart failure (NYHA classification II-III) despite diuretics and digitalis, and abnormal haemodynamics at baseline. Patients were randomly assigned to either pimobendan (average 10.3 mg.day-1, n = 119), or enalapril (average 10.7 mg.day-1, n = 123) in a double-blind fashion for 6 months. Forty-two pimobendan and 37 enalapril patients stopped the treatment, five pimobendan and six enalapril due to worsening of failure without death, whereas 13 and eight patients, respectively, died from cardiac disorders (ns). Other reasons for discontinuation and adverse events not leading to discontinuation were also comparable. Although Holter analysis at 14 days, but not at 6 months, indicated increased ventricular extrasystoles in pimobendan patients, these did not lead to serious clinical events. NYHA classification improved similarly in both groups, from 2.51 to 2.16 (pimobendan) and from 2.40 to 2.06 (enalapril). The number of patients needing a change in background therapy or hospitalization did not differ between the two groups. Haemodynamic variables at rest were improved by both compounds after 6 months. In contrast, only enalapril improved haemodynamics during exercise, and reduced the cardiothoracic ratio. The primary endpoint, exercise capacity, increased significantly during the first 3 months by 45 and 53 s, under pimobendan and enalapril, respectively, but, although unchanged thereafter, the improvement was no longer statistically significant at 6 months in either group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal androgens and testosterone as coronary risk factors in the Helsinki Heart Study

We investigated the role of adrenal androgens, cortisol, testosterone and sex-hormone binding globulin (SHBG) as coronary risk factors using a nested case-control design. The study population consisted of 62 cases with cardiac end-points and 97 controls on placebo during the last 4 years in the Helsinki Heart Study. Serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulfate (DHEAS), androstenedione, androstanediol glucuronide, cortisol, testosterone, and SHBG at the first annual visit of the 5-year study period were determined by radioimmunoassays. The only significant difference was found in DHEAS, with cases having higher levels than controls (P < 0.04). DHEAS levels were positively associated with smoking (P < 0.001), alcohol consumption (P < 0.04) and triglyceride levels (P < 0.002) and with systolic (P < 0.04) and diastolic (P < 0.006) blood pressures, and negatively associated with age (P < 0.01) and HDL-cholesterol (P < 0.03). The association between DHEAS and the CHD risk was studied using logistic regression analyses with the classical risk factors--age, smoking, blood pressure, and lipid levels--as covariates in the models. Studies of the joint effects of age and DHEAS disclosed that the risk associated with elevated DHEAS was confirmed to older men (odds ratio (OR) 7.3, 95%, CI 2.3-23.3). A similar analysis with smoking revealed that the DHEAS-related risk was mainly found in smokers (OR 3.4, 95% CI 1.5-8.2). One possible explanation for these results is that some form of mild steroid biosynthetic defect of the adrenals or functional adrenal hyperplasia associated with high DHEAS levels increases the CHD risk in this population.

The Helsinki Heart Study: coronary heart disease incidence during an extended follow-up

OBJECTIVES

To confirm that coronary heart disease (CHD) can be prevented by gemfibrozil treatment and to estimate the long-term effect of the treatment.

DESIGN

All participants of the Helsinki Heart Study, a controlled 5-year CHD primary prevention trial with gemfibrozil and placebo, were offered gemfibrozil treatment and biannual follow-up for 3.5 more years.

SETTING

By the end of the multi-clinic double-blind trial, a 34% difference in definite cardiac events (56 vs. 84; P < 0.2) had developed between the gemfibrozil and placebo groups.

SUBJECTS

There were 2046 dyslipidaemic men in the gemfibrozil group at randomization, 1961 started the extended follow-up; the comparison group comprised 2035 men, and 5 years later 1928 men.

INTERVENTIONS

Gemfibrozil was selected by 66.3% of gemfibrozil and 68.5% of placebo men without previous CHD end-points.

MAIN OUTCOME MEASURES

Definite fatal and non-fatal CHD events are reported, possible CHD events were recorded but reported selectively.

RESULTS

During the post-trial period the numbers of definite CHD events in both groups (54 vs. 47; NS) were smaller than expected without treatment, namely a reduction of around 40% for the original treatment groups. The mean incidence rates were in fact similar to that in the placebo group 5 years earlier. The post-trial CHD incidence was lowest amongst the placebo group men who later selected gemfibrozil. Cardiovascular mortality over the entire study period was similar but all-cause mortality was slightly higher amongst men of the original gemfibrozil group compared to the placebo group men (P = 0.19).

CONCLUSIONS

Thus prolonged gemfibrozil treatment postpones cardiac events. This protective effect presumably involves both attenuation of atherosclerosis and mechanisms related to acute cardiac events.

The Helsinki Heart Study: an 8.5-year safety and mortality follow-up

OBJECTIVES

Earlier monitoring of all symptoms, hospital admissions, cancer diagnoses and causes of death during gemfibrozil treatment had raised some suspicions which called for further follow-up.

DESIGN

Close monitoring of selected, potentially adverse events amongst treated subjects after a placebo-controlled trial and comparing occurrences to those in various untreated groups.

SETTING

All participants of the Helsinki Heart Study (a controlled, 5-year, multi-clinic coronary heart disease (CHD) primary prevention trial with gemfibrozil and placebo) were offered gemfibrozil treatment and twice yearly follow-up for 3.5 years. Untreated groups in the source population and national cancer statistics were utilized in comparisons.

SUBJECTS

Of the 2046 dyslipidaemic men initially randomized to gemfibrozil, 2002 survivors entered the 3.5-year follow-up; of the 2035 initial placebo men, 1992 continued to be monitored.

INTERVENTIONS

Gemfibrozil was chosen for the follow-up by 66.3% of the gemfibrozil-treated and 68.5% of the placebo-treated men.

MAIN OUTCOME MEASURES

Gastrointestinal symptoms, surgery, strokes, cancer incidence, mortality by cause.

RESULTS

Gastrointestinal symptoms remained more common in the original gemfibrozil group. After 8.5 years strokes numbered 32 (gemfibrozil) vs. 37 (placebo), violent deaths 16 vs. 14, and cancers 51 in both groups. Total mortality was equal during the original 5 years, but higher in the gemfibrozil group post-trial, leading to an 8.5 year mortality of 101 vs. placebo 83 (P = 0.19). This was mainly a result of higher cancer mortality in the gemfibrozil (30) than the placebo group (18, P = 0.08). An additional 18-month post-study registry follow-up disclosed 13 placebo and five gemfibrozil cancer deaths, altering the cancer mortality to gemfibrozil 35 vs. placebo 31 at 10 years.

CONCLUSIONS

The most plausible explanation for the discrepancy between cancer incidence and cancer-specific mortality, based mainly on comparison with untreated groups, is delayed diagnosis. The increased cancer and total mortality is most probably due to chance, based on the later reversal of trends.

Cigarette smoking is associated with elevated adrenal androgen response to adrenocorticotropin

Cigarette smoking alters the pattern of endogenous steroid levels. We examined this phenomenon in two separate male groups. Group A consisted of 189 dyslipidemic men participating in the Helsinki Heart Study and group B of 100 men including patients with heart disease and healthy controls. The subjects in the latter group underwent ACTH-testing. In group A, smokers had significantly higher basal androstenedione and dehydroepiandrosterone sulfate (DHEAS) levels and androstenedione/cortisol ratios than nonsmokers. Mean concentrations of cortisol, dehydroepiandrosterone (DHEA), androstanediol glucuronide, testosterone, and sex-hormone binding globulin (SHBG) did not differ between smokers and nonsmokers. In group B, smokers had lower high density lipoprotein (HDL)-cholesterol and apolipoprotein AI and higher triglyceride levels than nonsmokers. Basal androstenedione and ACTH stimulated androstenedione and DHEA concentrations were higher in smokers. No significant differences were found in basal insulin, SHBG, estrone, estradiol, testosterone, free testosterone, and dihydrotestosterone concentrations between smokers and nonsmokers. These results suggest that smoking decreases the activity of either 21- or 11 beta-hydroxylase in the adrenal cortex, which results in increased secretion of adrenal androgens.

Seasonal variation in high density lipoprotein cholesterol

We investigated the seasonal variation in high density lipoprotein cholesterol (HDL) in 142 dyslipidemic (non-HDL-cholesterol > or = 5.2 mmol/l) middle-aged men in the placebo group of the Helsinki Heart Study over the 5-year trial period. A seasonal pattern was found in HDL fluctuation, with a 4.5% drop during mid-winter (5-year mean 1.192 +/- 0.265 mmol/l) compared with a stable level (5-year mean 1.248 +/- 0.281 mmol/l) during the rest of the year (P < 0.001). A less pronounced seasonal variation in HDL was observed in 85 subjects receiving gemfibrozil. Although affecting pretrial HDL level in cross-sectional analyses, age, alcohol consumption, dietary adherence, physical activity and serum triglycerides had no influence on the seasonality of HDL variation. Smoking had a slight attenuating effect on the variation pattern. Pretrial HDL was influenced by relative weight, but there was also an inverse relationship between HDL and body weight variations, i.e. the annual drop in HDL coincided with the annual peak in body weight. However, seasonal HDL variation was not directly reflected in the annual variation in CHD incidence.

Efficacy of gemfibrozil in dyslipidaemic subjects with suspected heart disease. An ancillary study in the Helsinki Heart Study frame population

During screening in the Helsinki Heart Study (HHS), a 5-year coronary primary prevention trial with gemfibrozil, some 600 dyslipidaemic individuals were detected who exhibited symptoms and signs of possible coronary heart disease (CHD). These subjects were excluded from the primary study. To secure successful conduct in the HSS, an ancillary protocol was developed for the treatment of these individuals. Three-hundred and eleven subjects were randomized to receive gemfibrozil 600 mg twice daily and 317 subjects to receive a matching placebo over 5 years in a double-blind fashion. The end-point rate, consisting of fatal and non-fatal myocardial infarction and cardiac death, did not differ significantly between the placebo and gemfibrozil groups. The same was true for total mortality. Missing key prognostic factors, e.g. true prevalence of CHD, extent of coronary artery obstructions, degree of left ventricular dysfunction, and their distribution in the groups render the results less reliable and hence the data cannot be used to refute the thesis that treatment of dyslipidaemia in manifest CHD in successful.

Coronary heart disease incidence in NIDDM patients in the Helsinki Heart Study

OBJECTIVE

To determine coronary heart disease (CHD) incidence among dyslipidemic subjects with non-insulin-dependent diabetes mellitus (NIDDM) and to assess the effect of lipid-modifying treatment on serum and lipoprotein lipids and the CHD incidence in these patients.

RESEARCH DESIGN AND METHODS

Of the 4081 men participating in the Helsinki Heart Study, a coronary primary prevention trial with gemfibrozil in middle-aged men with high non-high-density lipoprotein (HDL) cholesterol (greater than 5.2 mM; 200 mg/dL), 135 had NIDDM at entry. The incidence of definite myocardial infarction and cardiac death and changes in serum and lipoprotein lipids were determined during the 5-yr trial in the NIDDM patients and compared with those observed in nondiabetic trial participants.

RESULTS

Compared with nondiabetic subjects, NIDDM patients had lower HDL cholesterol (P less than 0.001), higher triglyceride concentration (P less than 0.0001), and greater body mass index (P less than 0.001), there were more hypertensive patients (P less than 0.001) among them. The incidence of myocardial infarction and cardiac death was significantly higher among diabetic than nondiabetic participants (7.4 vs. 3.3%, respectively, P less than 0.02). CHD incidence in the gemfibrozil-treated diabetic men (n = 59) was 3.4% compared with 10.5% in the placebo group (NS). In multivariate analysis, diabetes (P less than 0.05), age (P less than 0.0001), smoking (P less than 0.0001), low HDL cholesterol (P less than 0.05), and high low-density lipoprotein cholesterol (P less than 0.005) were independently related to CHD incidence. Gemfibrozil-induced serum and lipoprotein lipid changes in diabetic patients were similar to those observed in nondiabetic subjects.

CONCLUSIONS

Compared with similarly dyslipidemic nondiabetic subjects, patients with NIDDM are at markedly increased risk of CHD. This elevated risk can be somewhat reduced by gemfibrozil.

Effects of gemfibrozil treatment on serum levels of androstanediol glucuronide and adrenal androgens

We have prospectively investigated the role of adrenal cortical androgens as a risk factor for coronary heart disease in the Helsinki Heart Study population. Simultaneously we studied the effects of gemfibrozil treatment on the serum levels of dehydroepiandrosterone (DHEA), its sulfate (DHEAS), and their metabolite androstanediol glucuronide (3 alpha AdiolG) with those of placebo. Gemfibrozil (n = 133) vs placebo (n = 159) treatment was associated with significant elevation of mean (SD) DHEAS (mumol/l) 8.35 (5.31) vs 6.98 (3.85); P less than 0.02, and of 3 alpha AdiolG (nmol/l) 17.45 (7.57) vs 8.62 (3.56); P less than 0.001), and of almost significant elevation of DHEA (nmol/l) 10.12 (6.64) vs 8.78 (5.86); P less than 0.07). These new observations suggest that gemfibrozil treatment increases the production and turnover of DHEA and DHEAS and may in addition stimulate the 5 alpha-reduction of androgens.

Leukocytes as a coronary risk factor in a dyslipidemic male population

The role of an elevated serum leukocyte count (WBC) as a coronary risk factor was investigated using a nested case-control design in dyslipidemic middle-aged men (n = 420) participating in the Helsinki Heart Study, a coronary primary prevention trial. Baseline WBC was significantly higher, 6.93 (2.11) x 10(9)/L in subjects with cardiac events, than in controls, 6.26 (1.88) x 10(9)/L; p less than 0.002. This association was time-dependent, however, since the difference was not significant for events occurring during the second half of the 5-year study. Using nonsmokers in the lowest WBC tertile as the reference sample, the relative risks in the highest WBC tertile were 1.86 (95% confidence intervals [CI] 0.81 to 4.28) for nonsmokers and 3.07 (95% CI 2.23 to 8.19) for smokers. Logistic regression analysis including smoking in the model disclosed an independent contribution of elevated WBC to coronary heart disease. We conclude that elevated leukocyte count was a coronary risk factor even in this dyslipidemic population.

Chronic Chlamydia pneumoniae infection as a risk factor for coronary heart disease in the Helsinki Heart Study

OBJECTIVE

To investigate in the prospective Helsinki Heart Study, whether chronic Chlamydia pneumoniae infection, indicated by elevated antibody titers against the pathogen, chlamydial lipopolysaccharide-containing immune complexes, or both, is a risk factor for coronary heart disease.

DESIGN AND SETTING

The Helsinki Heart Study was a randomized, double-blind, 5-year clinical trial to test the efficacy of gemfibrozil in reducing the risk for coronary heart disease. Participants were randomized to receive either gemfibrozil (2046 patients) or placebo (2035 patients). Fatal and nonfatal myocardial infarction and sudden cardiac death were the main study end points. Serum samples were collected at 3-month intervals from all patients.

PATIENTS

One hundred forty cardiac events occurred during the follow-up period. Serum samples from 103 case patients obtained 3 to 6 months before a cardiac end point were matched with those from controls for time point, locality, and treatment. Samples were tested for markers of chronic chlamydial infection.

MEASUREMENTS

Immunoglobulin A (IgA) and G (IgG) antibodies to C. pneumoniae were measured using the microimmunofluorescence method. Lipopolysaccharide-containing immune complexes were measured using two antigen-specific enzyme immunoassays, the lipopolysaccharide-capture and immunoglobulin M (IgM)-capture methods.

MAIN RESULTS

Using a conditional logistic regression model, odds ratios for the development of coronary heart disease were 2.7 (95% CI, 1.1 to 6.5) for elevated IgA titers, 2.1 (CI, 1.1 to 3.9) for the presence of immune complexes, and 2.9 (CI, 1.5 to 5.4) for the presence of both factors. If we adjusted for other coronary heart disease risk factors such as age, hypertension, and smoking, the corresponding values would be 2.3 (CI, 0.9 to 6.2), 1.8 (CI, 0.9 to 3.6), and 2.6 (CI, 1.3 to 5.2), respectively.

CONCLUSION

The results suggest that chronic C. pneumoniae infection may be a significant risk factor for the development of coronary heart disease.

Efficacy of conventional and sustained-release verapamil in stable angina pectoris

The efficacy of sustained-release (s.r.) verapamil and conventional verapamil were compared in a double blind, crossover study in 20 patients (age 53 +/- SD6 years) who had stable effort angina and had used betablockers and long acting nitrates for at least two weeks. All patients received s.r. verapamil 200 mg b.i.d. and conventional verapamil 120 mg t.i.d. in a randomised order for two weeks. A symptom limited bicycle exercise test was performed at the end of the patients' previous medication period with betablocker plus long acting nitrate and at the end of both verapamil treatments in the morning before drug administration and three hours thereafter. All the patients improved subjectively during both verapamil regimens according to NYHA classification and they had fewer anginal attacks. The time to onset of ST-segment depression during exercise remained shorter during beta-blockade and long acting nitrates than during both verapamil regimens (P less than 0.05). During the peak action three hours after drug administration conventional verapamil was most effective at comparable workloads (P less than 0.05), whereas the exercise time was slightly prolonged with s.r. verapamil before drug administration.

Joint effects of serum triglyceride and LDL cholesterol and HDL cholesterol concentrations on coronary heart disease risk in the Helsinki Heart Study. Implications for treatment

BACKGROUND

We studied the joint effect of baseline triglyceride and lipoprotein cholesterol levels on the incidence of cardiac end points in the trial group (n = 4,081) of the Helsinki Heart Study, a 5-year randomized coronary primary prevention trial among dyslipidemic middle-aged men. The relative risks (RR) were calculated using Cox proportional hazards models with a dummy variable technique that allows simultaneous study of subgroup combinations from the placebo and treatment groups.

METHODS AND RESULTS

In the placebo group (n = 2,045), the low density lipoprotein cholesterol (LDL-C)/high density lipoprotein cholesterol (HDL-C) ratio was the best single predictor of cardiac events. This ratio in combination with the serum triglyceride level revealed a high-risk subgroup: subjects with LDL-C/HDL-C ratio greater than 5 and triglycerides greater than 2.3 mmol/l had a RR of 3.8 (95% CI, 2.2-6.6) compared with those with LDL-C/HDL-C ratio less than or equal to 5 and triglyceride concentration less than or equal to 2.3 mmol/l. In subjects with triglyceride concentration greater than 2.3 mmol/l and LDL-C/HDL-C ratio less than or equal to 5, RR was close to unity (1.1), whereas in those with triglyceride level less than or equal to 2.3 mmol/l and LDL-C/HDL-C ratio greater than 5, RR was 1.2. The high-risk group with LDL-C/HDL-C ratio greater than 5 and triglyceride level greater than 2.3 mmol/l profited most from treatment with gemfibrozil, with a 71% lower incidence of coronary heart disease events than the corresponding placebo subgroup. In all other subgroups, the reduction in CHD incidence was substantially smaller.

CONCLUSIONS

Serum triglyceride concentration has prognostic value, both for assessing coronary heart disease risk and in predicting the effect of gemfibrozil treatment, especially when used in combination with HDL-C and LDL-C.

Relationship of skeletal muscle fiber type to serum high density lipoprotein cholesterol and apolipoprotein A-I levels

We measured the percentage of slow-twitch (ST) muscle fibers in the lateral portion of the quadriceps femoris muscle in 41 healthy sedentary male controls, 35 active male joggers, and 26 male coronary heart disease (CHD) patients. We then compared these percentages with serum levels of total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C) and apolipoprotein A-I (apo A-I) found in these 102 middle-aged men. The percentage of ST muscle fibers in all men correlated positively with serum HDL-C (r = 0.57, P less than 0.001) and with apo A-I (r = 0.60, P less than 0.001) and negatively with triglycerides (r = -0.43, P less than 0.001). The proportion of ST fibers in joggers (65%; 61-69%, 95% confidence interval) was higher (P less than 0.001) than in sedentary controls (48%; 44-52%) or in CHD patients (44%; 39-49%). Moreover, 89% of the joggers had a proportion of ST fibers higher than 50%, whilst in sedentary controls and in CHD patients these values were 46% and 38%, respectively. Positive correlations were found between the percentage of ST fibers and both HDL-C and apo A-I in controls (r = 0.33, P less than 0.05 and r = 0.34, P less than 0.05) and in joggers (r = 0.46, P less than 0.01, and r = 0.40, P less than 0.05), respectively. Negative correlations in controls (r = -0.34, P less than 0.05) and in CHD patients (r = -0.43, P less than 0.05) were also found between the percentage of ST fibers and serum TG.(ABSTRACT TRUNCATED AT 250 WORDS)

Lipoprotein (a) and coronary heart disease risk: a nested case-control study of the Helsinki Heart Study participants

To prospectively assess the role of lipoprotein(a) (Lp(a)) as a risk factor for coronary heart disease, the serum Lp(a) concentration was determined in 130 subjects without coronary events and in 138 patients in whom coronary events (i.e. fatal and non-fatal myocardial infarction and cardiac death) occurred during the 5-year Helsinki Heart Study. The participants of this study (n = 4081) were 40-55-year-old men who were devoid of coronary heart disease at the beginning of the trial; half were randomized to gemfibrozil and the other half to placebo treatment. In patients with coronary events blood pressure and total cholesterol were not significant predictors of the events but their LDL cholesterol was higher than compared to the control group in this cohort (P less than 0.05). The serum Lp(a) concentration was determined by immunoassay from samples obtained 3 months after the beginning of the trial and then stored at -20 degrees C until analysed. Studies on the effect of long term storage at -20 degrees C on serum Lp(a) levels did not reveal significant changes in Lp(a) concentration in sera stored for up to 8.5 years. The distribution of Lp(a) concentrations were similar in the men with coronary events and the controls. Nor did the mean or median levels of Lp(a) differ significantly between the two groups. Measurements of Lp(a) levels in fresh samples using 2 different immunoassays did not reveal any significant difference between the participants who had survived a myocardial infarction or participants without cardiac events. Thus, we conclude that in the Helsinki Heart Study cohort the serum Lp(a) level was not a predictor of future coronary events.

The Helsinki Heart Study: central findings and clinical implications

This paper describes the central findings and discusses the clinical implications of the Helsinki Heart Study. This was a controlled primary prevention trial to test the hypothesis that using gemfibrozil to lower the concentrations of serum low density lipoprotein (LDL) and very low density lipoprotein (VLDL) and to raise that of high density lipoprotein (HDL) protects subjects against coronary heart disease.

Coronary collateral circulation

The occurrence and influence of coronary collateral circulation and obstruction of the supplying coronary arteries on left ventricular contractility, prevalence of myocardial infarction, and bicycle exercise ergometer test were studied in a random sample of 286 patients with angiographically documented coronary artery disease. Collaterals appeared increasingly in all three main coronary arteries with grade of obstruction. The highest prevalence of collaterals occurred in stenosis of the right coronary artery (60%), followed by the left descending artery (45%); they occurred least in the left circumflex artery (21%) (p less than 0.001). The frequency of intra-arterial collateral circulation was 42%, 11%, and 12%, respectively (p less than 0.001). With total occlusion of the left anterior descending coronary artery, 22% of the patients had normokinetic anterior and apical left ventricular wall when collaterals were present. More often, the inferior wall showed normal contraction with total occlusion of the right coronary artery and collaterals [52%, p less than 0.001 compared with left anterior descending artery (LAD)]. The prevalence of inferior myocardial infarction was 39%, with collateral circulation to the totally occluded right coronary artery. The respective prevalence of anterior infarction and total occlusion in the left coronary artery was 58% (p less than 0.02). The presence or absence of collaterals had no obvious influence on ST-segment response during bicycle ergometer test. In triple-vessel disease, peak work capacity was better when collaterals to LAD were not jeopardized (427 kpm) than when jeopardized (321 kpm) (p less than 0.02).

Lipoproteins and coronary heart disease in the Helsinki Heart Study

The changes in serum lipids in men treated with gemfibrozil in the Helsinki Heart Study, a controlled primary prevention trial of coronary heart disease, varied according to baseline lipid levels, type of dyslipidaemia, and treatment compliance. In subjects with the best treatment compliance, gemfibrozil induced mean decreases of 14% in total cholesterol, 15% in low density lipoprotein (LDL)-cholesterol, and 45% in triglycerides, and a mean increase of 14% in high density lipoprotein (HDL)-cholesterol, compared with placebo. These changes were significantly greater than those observed in the entire cohort. There was a strong association between baseline levels and the response to treatment (expressed as the difference in mmol l-1 between the gemfibrozil- and placebo-treated groups) for LDL-cholesterol and triglycerides. In contrast, the corresponding change in HDL-cholesterol was not dependent on the baseline level. Ultracentrifuge analysis in a subsample of the cohort revealed that gemfibrozil raised the level of HDL3-cholesterol but had little effect on HDL2-cholesterol. The gemfibrozil-associated reduction in the incidence of definite coronary events varied according to lipid values at baseline and their changes during treatment. The greatest reductions were seen in subjects with low initial HDL-cholesterol and high initial triglycerides. In the gemfibrozil group, the increase in HDL-cholesterol and decrease in LDL-cholesterol were associated with significantly lower risk of coronary events.

Reduction in Q wave myocardial infarctions with gemfibrozil in the Helsinki Heart Study

The Helsinki Heart Study demonstrated a 34% (p less than 0.02) reduction in the incidence of cardiac end points (myocardial infarction and cardiac death) with the use of gemfibrozil compared with the use of a placebo in dyslipidemic middle-aged men. The major effect was confined to nonfatal myocardial infarctions. In this study we analyzed the effect of gemfibrozil therapy on the incidences of Q wave and non-Q wave infarctions, since the long-term prognoses of these two types of myocardial infarction may be different. The analyses indicated a 45% reduction (P less than 0.02, log-rank test) in the cumulative incidence of Q wave infarctions in the gemfibrozil group without a statistically significant effect on either the rate of non-Q wave infarctions or of coronary deaths. The reduction in the incidence of Q wave infarctions became evident during the second half of the 5-year study period.

HDL-cholesterol as a risk factor in coronary heart disease. An update of the Helsinki Heart Study

The aim of the Helsinki Heart Study, a 5-year primary prevention placebo-controlled study involving 4081 dyslipidaemic men (aged 40 to 55 years), was to investigate if increasing high density lipoprotein (HDL)-cholesterol plasma levels and decreasing low density lipoprotein (LDL)-cholesterol levels would reduce the incidence of coronary heart disease. Gemfibrozil 600mg twice daily was administered to induce these changes in lipoprotein levels. Baseline HDL-cholesterol levels in the study group were similar to those in the general population. Data from patients treated with placebo were analysed to investigate the influence of HDL-cholesterol levels on the incidence of coronary heart disease. Using the number of cardiac end-points per 1000 person-years to indicate the risk of coronary heart disease, it was clear that elevated HDL-cholesterol levels reduced the risk of coronary heart disease while the incidence increased at low HDL-cholesterol levels. This relationship was not altered when the effect of HDL-cholesterol levels was analysed jointly with other coronary risk factors (age, smoking or blood pressure). A weaker association was seen between LDL-cholesterol and risk of coronary heart disease, and triglycerides appeared to have no significant effect on the incidence of the disease. The data clearly suggest that HDL-cholesterol is a strong predictor of the incidence of coronary heart disease in the placebo group of the Helsinki Heart Study.

Relation between baseline lipid and lipoprotein values and the incidence of coronary heart disease in the Helsinki Heart Study

A 34% reduction in the incidence of definite coronary heart disease events was observed in dyslipidemic men treated with gemfibrozil in the Helsinki Heart Study, a controlled 5-year, double-blind primary prevention trial for coronary heart disease. Over the entire study period, gemfibrozil therapy induced mean decreases of 10% in serum total cholesterol levels, 11% in low-density lipoprotein (LDL) cholesterol, 35% in triglyceride levels, and a mean increase of 11% in high-density lipoprotein (HDL) cholesterol level, compared with placebo. The differences in percentage changes in LDL cholesterol between gemfibrozil- and placebo-treated men varied among Fredrickson hyperlipoproteinemia types; after 1 year of treatment the difference was greatest for type IIA hyperlipoproteinemia (14 percentage units) and smallest for IIB hyperlipoproteinemia (3 percentage units). The treatment-associated changes in HDL cholesterol and triglycerides did not differ materially between the 3 hyperlipoproteinemia types, when calculated in the same way. The gemfibrozil-associated reduction in incidence of definite coronary events varied among Fredrickson types and among tertiles of baseline HDL cholesterol and triglycerides. The greatest rate reductions were seen in subjects with type IIB hyperlipoproteinemia, low initial HDL level or high initial triglycerides. These results suggest that subjects with low HDL cholesterol and type IIB hyperlipoproteinemia (and possibly type IV hyperlipoproteinemia) would benefit from treatment with gemfibrozil.

Angiographic findings in patients exhibiting ischemia after oral dipyridamole

We have assessed the angiographic features of a group of 37 patients given oral dipyridamole and 37 patients given matching placebo. Both groups represented severe coronary arterial disease and were studied prior to bypass surgery. Six patients (16%) had angina and 13 patients (35%) had electrocardiographic changes after dipyridamole. All the patients in the control group were nonresponders. In the group given dipyridamole the patients responding with angina had significantly more compromised collaterals than the patients without chest pain (P = 0.021). The same applied to the patients with electrocardiographic changes versus those with no electrocardiographic changes (P = 0.034). No differences between responders and nonresponders could be found in terms of the severity of coronary arterial disease, severity of anginal symptoms, exercise tolerance, antianginal medication, number of past myocardial infarctions, and left ventricular ejection fraction. In conclusion, the data strongly suggest that ischaemic responses to dipyridamole originate from myocardial steal accentuated by compromised flow in collateral vessels.

A dose-response study of amlodipine in mild to moderate hypertension

The antihypertensive efficacy and suitability for once daily dosing of amlodipine, a new calcium antagonist, was studied in a series of 205 patients with mild to moderate hypertension. The study was conducted double-blind in 13 centres. The starting doses of amlodipine were 1.25, 2.5 and 5 mg, respectively, which were doubled after 4 weeks if normotension or a preset target blood pressure was not reached. Target blood pressure was reached in 25% of patients with placebo, 41% with 2.5 mg of amlodipine, 56% with 5 mg of amlodipine and 73% with 10 mg of amlodipine once daily. The drug was well tolerated at all dose levels and no changes occurred in heart rate, body weight or electrocardiogram during treatment. Amlodipine is a useful new calcium antagonist for the treatment of hypertension producing smooth, dose-dependent blood pressure reductions with convenient once daily dosing.

Lipid alterations and decline in the incidence of coronary heart disease in the Helsinki Heart Study

In the Helsinki Heart Study, a randomized five-year, double-blind trial, a 34% reduction in the incidence of coronary heart disease (CHD) was observed in dyslipidemic men treated with gemfibrozil. Averaged over the five years of the trial, gemfibrozil therapy produced, compared with placebo, mean decreases of 10% in serum total cholesterol level, 14% in non-high-density lipoprotein (HDL) cholesterol level, 11% in low-density lipoprotein (LDL) cholesterol level, 35% in triglyceride level, and a mean increase of 11% in HDL cholesterol level from baseline levels measured prior to treatment. While changes in HDL cholesterol level were similar in all Fredrickson types, the effect on concentrations of total cholesterol and LDL cholesterol was largest in type IIA and on LDL minimal in type IV. The reduction of CHD incidence over placebo was largest in type IIB and smallest in type IIA. The lipid changes were dependent on lipid levels prior to treatment and on compliance with the medication regimen. When risk factors for CHD, including age, blood pressure, smoking and drinking habits, baseline lipid levels, and exercise and relative weight, were controlled by applying the Cox proportional hazards model, the changes in serum HDL and LDL cholesterol levels were both statistically significantly associated with the decline in CHD incidence within the gemfibrozil-treated group. The large decrease in serum triglyceride levels had relatively small effect on CHD incidence. Thus, the results of this study, together with earlier observations, suggest that both elevating HDL and lowering LDL cholesterol levels are effective in the primary prevention of CHD.

Helsinki Heart Study. New perspectives in the prevention of coronary heart disease

The Helsinki Heart Study tested the effect of modifying plasma low density lipoprotein (LDL)- and high density lipoprotein (HDL)-cholesterol on the primary prevention of coronary heart disease in middle-aged men with non-HDL-cholesterol greater than or equal to 5.2 mmol/L (200 mg/dl). One group (2046 men) received 600mg of gemfibrozil twice daily, and the other (2035 men) received placebo. Averaged over the 5-year trial period, gemfibrozil induced mean decreases of 11% in LDL-cholesterol and 35% in triglycerides and a mean increase of 11% in HDL-cholesterol compared with placebo. These changes were accompanied by a 34% reduction (number of end-points; 56 vs 84) in the incidence of coronary heart disease. The reduction was largest in subjects with type IIB hyperlipoproteinaemia and smallest in subjects with type IIA hyperlipoproteinaemia. The changes in serum HDL- and LDL-cholesterol during the trial were associated (p less than 0.02 and p less than 0.05, respectively) with the risk of coronary heart disease in the gemfibrozil group, but not in the placebo group.

Helsinki Heart Study: primary-prevention trial with gemfibrozil in middle-aged men with dyslipidemia. Safety of treatment, changes in risk factors, and incidence of coronary heart disease

In a randomized, double-blind five-year trial, we tested the efficacy of simultaneously elevating serum levels of high-density lipoprotein (HDL) cholesterol and lowering levels of non-HDL cholesterol with gemfibrozil in reducing the risk of coronary heart disease in 4081 asymptomatic middle-aged men (40 to 55 years of age) with primary dyslipidemia (non-HDL cholesterol greater than or equal to 200 mg per deciliter [5.2 mmol per liter] in two consecutive pretreatment measurements). One group (2051 men) received 600 mg of gemfibrozil twice daily, and the other (2030 men) received placebo. Gemfibrozil caused a marked increase in HDL cholesterol and persistent reductions in serum levels of total, low-density lipoprotein (LDL), and non-HDL cholesterol and triglycerides. There were minimal changes in serum lipid levels in the placebo group. The cumulative rate of cardiac end points at five years was 27.3 per 1,000 in the gemfibrozil group and 41.4 per 1,000 in the placebo group--a reduction of 34.0 percent in the incidence of coronary heart disease (95 percent confidence interval, 8.2 to 52.6; P less than 0.02; two-tailed test). The decline in incidence in the gemfibrozil group became evident in the second year and continued throughout the study. There was no difference between the groups in the total death rate, nor did the treatment influence the cancer rates. The results are in accord with two previous trials with different pharmacologic agents and indicate that modification of lipoprotein levels with gemfibrozil reduces the incidence of coronary heart disease in men with dyslipidemia.

The Helsinki Heart Study: basic design and randomization procedure

The Helsinki Heart Study is a coronary primary prevention trial in a group of middle aged men with lipid abnormalities. Its aim is to investigate the effects on the incidence of coronary heart disease of simultaneously lowering serum total and low density lipoprotein (LDL)-cholesterol and elevating high density lipoprotein (HDL)-cholesterol with gemfibrozil, over a period of 5 years. Participants were selected from a population of 23 531 men between 40 and 55 years of age. The mean serum total cholesterol among 18 966 screened subjects was 6.3 mmol l-1 (245 mg dl-1) and the mean HDL-cholesterol 1.3 mmol l-1 (50.3 mg dl-1). All subjects meeting the lipid acceptance criterion of non-HDL-cholesterol (i.e. total cholesterol minus HDL-cholesterol) greater than 5.2 mmol l-1 (200 mg dl-1) on two separate occasions two to three months apart, who were free from coronary heart disease or other major illness, were invited to participate. The total cholesterol level for the final 4081 study participants was 7.5 mmol l-1 (290 mg dl-1) and HDL-cholesterol was 1.23 mmol l-1 (47.6 mg dl-1). Mean systolic and diastolic blood pressures were 141.7 and 91.3 mmHg. About 15% of participants were hypertensive and 36% were smokers. A total of 2051 men were randomly allocated to receive gemfibrozil 600 mg twice daily and 2030 matching placebo capsules. A cholesterol-lowering diet was also prescribed for all participants. The randomized treatment groups were well balanced. Equal distribution of major risk factors was achieved in relevant sub-groups. This report describes the procedures involved in setting up the study, summarizes the baseline data obtained and reviews the success of the randomization procedure. Finally, it compares the design of this study with that of some other major preventive trials.

Serum lipid changes in a one-year, multicenter, double-blind comparison of doxazosin and atenolol for mild to moderate essential hypertension

Proatherogenic changes in serum lipid concentrations have been implicated as one of the major risk factors in the development of coronary artery disease. In a double-blind study, the new alpha 1-adrenoceptor inhibitor, doxazosin, was compared with atenolol for effects on the serum lipid profile. Ninety-six hypertensive patients were treated for up to 1 year with either doxazosin or atenolol once daily. There were statistically significant differences (p less than or equal to 0.01) between doxazosin and atenolol after 20 to 52 weeks of treatment in changes from baseline total triglyceride levels, high density lipoprotein (HDL) cholesterol levels and HDL/total cholesterol ratio. The percentage of change from baseline and the statistical significance of the difference between treatment groups were: total triglycerides, doxazosin -5.9%, atenolol +32.4% (p = 0.01); HDL cholesterol, doxazosin +7.2%, atenolol -5.6% (p = 0.007) and HDL/total cholesterol ratio: doxazosin +8.7%, atenolol -6.2% (p = 0.006). All mean changes were in favor of doxazosin therapy. In addition, doxazosin treatment beneficially decreased total serum cholesterol levels (-1.6%) compared with atenolol (+0.6%), although not to a significant degree. The differences were maintained in the cohort of 67 patients treated for a full year. The favorable change exerted by doxazosin on the lipid profile suggests that it may have a beneficial influence on the lipid risk factor. These results, together with the sustained decrease in blood pressure achieved for up to 1 year of therapy, suggest that doxazosin may reduce the risk of coronary artery disease in susceptible patients.