Effects of statin therapy on diagnoses of new-onset diabetes and worsening glycaemia in large-scale randomised blinded statin trials: an individual participant data meta-analysis

BACKGROUND

Previous meta-analyses of summary data from randomised controlled trials have shown that statin therapy increases the risk of diabetes, but less is known about the size or timing of this effect, or who is at greatest risk. We aimed to address these gaps in knowledge through analysis of individual participant data from large, long-term, randomised, double-blind trials of statin therapy.

METHODS

We conducted a meta-analysis of individual participant data from randomised controlled trials of statin therapy that participated in the CTT Collaboration. All double-blind randomised controlled trials of statin therapy of at least 2 years' scheduled duration and with at least 1000 participants were eligible for inclusion in this meta-analysis. All recorded diabetes-related adverse events, treatments, and measures of glycaemia were sought from eligible trials. Meta-analyses assessed the effects of allocation to statin therapy on new-onset diabetes (defined by diabetes-related adverse events, use of new glucose-lowering medications, glucose concentrations, or HbA1c values) and on worsening glycaemia in people with diabetes (defined by complications of glucose control, increased use of glucose-lowering medication, or HbA1c increase of ≥0·5%). Standard inverse-variance-weighted meta-analyses of the effects on these outcomes were conducted according to a prespecified protocol.

FINDINGS

Of the trials participating in the CTT Collaboration, 19 trials compared statin versus placebo (123 940 participants, 25 701 [21%] with diabetes; median follow-up of 4·3 years), and four trials compared more versus less intensive statin therapy (30 724 participants, 5340 [17%] with diabetes, median follow-up of 4·9 years). Compared with placebo, allocation to low-intensity or moderate-intensity statin therapy resulted in a 10% proportional increase in new-onset diabetes (2420 of 39 179 participants assigned to receive a statin [1·3% per year] vs 2214 of 39 266 participants assigned to receive placebo [1·2% per year]; rate ratio [RR] 1·10, 95% CI 1·04-1·16), and allocation to high-intensity statin therapy resulted in a 36% proportional increase (1221 of 9935 participants assigned to receive a statin [4·8% per year] vs 905 of 9859 participants assigned to receive placebo [3·5% per year]; 1·36, 1·25-1·48). For each trial, the rate of new-onset diabetes among participants allocated to receive placebo depended mostly on the proportion of participants who had at least one follow-up HbA1c measurement; this proportion was much higher in the high-intensity than the low-intensity or moderate-intensity trials. Consequently, the main determinant of the magnitude of the absolute excesses in the two types of trial was the extent of HbA1c measurement rather than the proportional increase in risk associated with statin therapy. In participants without baseline diabetes, mean glucose increased by 0·04 mmol/L with both low-intensity or moderate-intensity (95% CI 0·03-0·05) and high-intensity statins (0·02-0·06), and mean HbA1c increased by 0·06% (0·00-0·12) with low-intensity or moderate-intensity statins and 0·08% (0·07-0·09) with high-intensity statins. Among those with a baseline measure of glycaemia, approximately 62% of new-onset diabetes cases were among participants who were already in the top quarter of the baseline distribution. The relative effects of statin therapy on new-onset diabetes were similar among different types of participants and over time. Among participants with baseline diabetes, the RRs for worsening glycaemia were 1·10 (1·06-1·14) for low-intensity or moderate-intensity statin therapy and 1·24 (1·06-1·44) for high-intensity statin therapy compared with placebo.

INTERPRETATION

Statins cause a moderate dose-dependent increase in new diagnoses of diabetes that is consistent with a small upwards shift in glycaemia, with the majority of new diagnoses of diabetes occurring in people with baseline glycaemic markers that are close to the diagnostic threshold for diabetes. Importantly, however, any theoretical adverse effects of statins on cardiovascular risk that might arise from these small increases in glycaemia (or, indeed, from any other mechanism) are already accounted for in the overall reduction in cardiovascular risk that is seen with statin therapy in these trials. These findings should further inform clinical guidelines regarding clinical management of people taking statin therapy.

FUNDING

British Heart Foundation, UK Medical Research Council, and Australian National Health and Medical Research Council.

Long-term cardiovascular risks and the impact of statin treatment on socioeconomic inequalities: a microsimulation model

BACKGROUND

UK cardiovascular disease (CVD) incidence and mortality have declined in recent decades but socioeconomic inequalities persist.

AIM

To present a new CVD model, and project health outcomes and the impact of guideline-recommended statin treatment across quintiles of socioeconomic deprivation in the UK.

DESIGN AND SETTING

A lifetime microsimulation model was developed using 117 896 participants in 16 statin trials, 501 854 UK Biobank (UKB) participants, and quality-of-life data from national health surveys.

METHOD

A CVD microsimulation model was developed using risk equations for myocardial infarction, stroke, coronary revascularisation, cancer, and vascular and non-vascular death, estimated using trial data. The authors calibrated and further developed this model in the UKB cohort, including further characteristics and a diabetes risk equation, and validated the model in UKB and Whitehall II cohorts. The model was used to predict CVD incidence, life expectancy, quality-adjusted life years (QALYs), and the impact of UK guideline-recommended statin treatment across socioeconomic deprivation quintiles.

RESULTS

Age, sex, socioeconomic deprivation, smoking, hypertension, diabetes, and cardiovascular events were key CVD risk determinants. Model-predicted event rates corresponded well to observed rates across participant categories. The model projected strong gradients in remaining life expectancy, with 4-5-year (5-8 QALYs) gaps between the least and most socioeconomically deprived quintiles. Guideline-recommended statin treatment was projected to increase QALYs, with larger gains in quintiles of higher deprivation.

CONCLUSION

The study demonstrated the potential of guideline-recommended statin treatment to reduce socioeconomic inequalities. This CVD model is a novel resource for individualised long-term projections of health outcomes of CVD treatments.

The Interaction of a Diabetes Gene Risk Score With 3 Different Antihypertensive Medications for Incident Glucose-level Elevation

BACKGROUND

Elevations of fasting glucose (FG) levels are frequently encountered in people treated with thiazide diuretics. The risk is lower in people treated with ACE inhibitors (ACEi). To determine if genetic factors play a role in FG elevation, we examined the interaction of a diabetes gene risk score (GRS) with the use of 3 different antihypertensive medications.

METHODS

We examined 376 nondiabetic hypertensive individuals with baseline FG <100 mg/dl who were genotyped for 24 genes associated with risk of elevated glucose levels. All participants had ≥1 follow-up FG level over 6 years of follow-up. Participants were randomized to treatment with a thiazide-like diuretic (chlorthalidone), a calcium channel blocker (CCB; amlodipine), or an ACEi (lisinopril). Outcomes were an FG increase of ≥13 or ≥27 mg/dl, the upper 75% and 90% FG increase in the parent cohort from which the present cohort was obtained. Odds ratios were adjusted for factors that increase FG levels.

RESULTS

For every 1 allele increase in GRS, the adjusted odds ratios (ORs) were 1.06 (95% confidence interval (CI): 0.99, 1.14; P = 0.06) and 1.09 (95% CI: 0.99, 1.20; P = 0.08). When results were examined by randomized medications, participants randomized to amlodipine had statistically significant odds for either outcome (OR: 1.23; 95% CI: 1.03, 1.48; P = 0.01 and OR: 1.31; 95% CI: 1.06, 1.62; P = 0.01). No such risk increase was found in participants randomized to the other 2 medications.

CONCLUSIONS

A diabetes GRS predicts FG elevation in people treated with a CCB, but not with an ACEi or diuretic. These findings require confirmation.

CLINICAL TRIALS REGISTRATION

Trial number NCT00000542.

Baseline Quality of Life and Risk of Stroke in the ALLHAT Study (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial)

BACKGROUND AND PURPOSE

The visual analogue scale is a self-reported, validated tool to measure quality of life (QoL). Our purpose was to determine whether baseline QoL predicted strokes in the ALLHAT study (Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial) and evaluate determinants of poststroke change in QoL. In the ALLHAT study, among the 33 357 patients randomized to treatment arms, 1525 experienced strokes; 1202 (79%) strokes were nonfatal. This study cohort includes 32 318 (97%) subjects who completed the baseline visual analogue scale QoL estimate.

METHODS

QoL was measured on a visual analogue scale and adjusted using a Torrance transformation (transformed QoL [TQoL]). Kaplan-Meier curves and adjusted proportional hazards analyses were used to estimate the effect of TQoL on the risk of stroke, on a continuous scale (0-1) and by quartiles (≤0.81, >0.81≤0.89, >0.89≤0.95, >0.95). We analyzed the change from baseline to first poststroke TQoL using adjusted linear regression.

RESULTS

After adjusting for multiple stroke risk factors, the hazard ratio for stroke events for baseline TQoL was 0.93 (95% confidence interval, 0.89-0.98) per 0.1 U increase. The lowest baseline TQoL quartile had a 20% increased stroke risk (hazard ratio=1.20 [95% confidence interval, 1.00-1.44]) compared with the reference highest quartile TQoL. Poststroke TQoL change was significant within all treatment groups (P≤0.001). Multivariate regression analysis revealed that baseline TQoL was the strongest predictor of poststroke TQoL with similar results for the untransformed QoL.

CONCLUSIONS

The lowest baseline TQoL quartile had a 20% higher stroke risk than the highest quartile. Baseline TQoL was the only factor that predicted poststroke change in TQoL.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000542.

Abstract 100: Hip and Pelvic Fracture Risk in Adults Treated with Three Different Classes of Antihypertensive Medications: The ALLHAT Study

Observational studies suggest that thiazide-type diuretics reduce fracture risk compared to other antihypertensive medications. The effects of calcium channel blockers (CCB) and angiotensin converting-enzyme inhibitors (ACEi) on fracture risk have not been well studied. We examined the relationship of antihypertensive drug therapy and hip and pelvic fracture hospitalizations in the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial ( ALLHAT ). It included >33,000 participants randomized to the thiazide-type diuretic chlorthalidone (C), ACEi lisinopril (L), or CCB amlodipine (A) as first line hypertension (HTN) therapy. Mean follow up was 4.9 years during the randomized phase (in-trial), and 5 additional years after the conclusion of the trial (post-trial) using linkage to national data bases. Risks of hip and pelvic fractures for L and A relative to C were derived from Cox models. There were 341 hip and pelvic fractures in-trial. Participants assigned C had the lowest risk and those assigned L the highest ( Figure 1a). The adjusted risk for L compared to C was 1.33 (95% CI 1.02-1.73; p=.04). Participants assigned A had intermediate risk compared to C (HR 1.22, 95% CI 0.93-1.59). During the combined in-trial and post-trial periods ( Figure 1b ), there were 646 fractures; the results were similar to the in-trial results, although differences were not statistically significant. Participants randomized to C continued to have the lowest risk of fractures after in-trial period, suggesting a legacy effect from prior C use. These findings have public health importance given the high prevalence of HTN in older adults and the widespread use of A and L in older adults.

Hydroxycarbamide versus chronic transfusion for maintenance of transcranial doppler flow velocities in children with sickle cell anaemia-TCD With Transfusions Changing to Hydroxyurea (TWiTCH): a multicentre, open-label, phase 3, non-inferiority trial

BACKGROUND

For children with sickle cell anaemia and high transcranial doppler (TCD) flow velocities, regular blood transfusions can effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxycarbamide (hydroxyurea) in this setting is unknown; we performed the TWiTCH trial to compare hydroxyurea with standard transfusions.

METHODS

TWiTCH was a multicentre, phase 3, randomised, open-label, non-inferiority trial done at 26 paediatric hospitals and health centres in the USA and Canada. We enrolled children with sickle cell anaemia who were aged 4-16 years and had abnormal TCD flow velocities (≥ 200 cm/s) but no severe vasculopathy. After screening, eligible participants were randomly assigned 1:1 to continue standard transfusions (standard group) or hydroxycarbamide (alternative group). Randomisation was done at a central site, stratified by site with a block size of four, and an adaptive randomisation scheme was used to balance the covariates of baseline age and TCD velocity. The study was open-label, but TCD examinations were read centrally by observers masked to treatment assignment and previous TCD results. Participants assigned to standard treatment continued to receive monthly transfusions to maintain 30% sickle haemoglobin or lower, while those assigned to the alternative treatment started oral hydroxycarbamide at 20 mg/kg per day, which was escalated to each participant's maximum tolerated dose. The treatment period lasted 24 months from randomisation. The primary study endpoint was the 24 month TCD velocity calculated from a general linear mixed model, with the non-inferiority margin set at 15 cm/s. The primary analysis was done in the intention-to-treat population and safety was assessed in all patients who received at least one dose of assigned treatment. This study is registered with ClinicalTrials.gov, number NCT01425307.

FINDINGS

Between Sept 20, 2011, and April 17, 2013, 159 patients consented and enrolled in TWiTCH. 121 participants passed screening and were then randomly assigned to treatment (61 to transfusions and 60 to hydroxycarbamide). At the first scheduled interim analysis, non-inferiority was shown and the sponsor terminated the study. Final model-based TCD velocities were 143 cm/s (95% CI 140-146) in children who received standard transfusions and 138 cm/s (135-142) in those who received hydroxycarbamide, with a difference of 4·54 (0·10-8·98). Non-inferiority (p=8·82 × 10(-16)) and post-hoc superiority (p=0·023) were met. Of 29 new neurological events adjudicated centrally by masked reviewers, no strokes were identified, but three transient ischaemic attacks occurred in each group. Magnetic resonance brain imaging and angiography (MRI and MRA) at exit showed no new cerebral infarcts in either treatment group, but worsened vasculopathy in one participant who received standard transfusions. 23 severe adverse events in nine (15%) patients were reported for hydroxycarbamide and ten serious adverse events in six (10%) patients were reported for standard transfusions. The most common serious adverse event in both groups was vaso-occlusive pain (11 events in five [8%] patients with hydroxycarbamide and three events in one [2%] patient for transfusions).

INTERPRETATION

For high-risk children with sickle cell anaemia and abnormal TCD velocities who have received at least 1 year of transfusions, and have no MRA-defined severe vasculopathy, hydroxycarbamide treatment can substitute for chronic transfusions to maintain TCD velocities and help to prevent primary stroke.

FUNDING

National Heart, Lung, and Blood Institute, National Institutes of Health.

Effects of hydroxyurea treatment for patients with hemoglobin SC disease

Although hemoglobin SC (HbSC) disease is usually considered less severe than sickle cell anemia (SCA), which includes HbSS and HbS/β(0) -thalassemia genotypes, many patients with HbSC experience severe disease complications, including vaso-occlusive pain, acute chest syndrome, avascular necrosis, retinopathy, and poor quality of life. Fully 20 years after the clinical and laboratory efficacy of hydroxyurea was proven in adult SCA patients, the safety and utility of hydroxyurea treatment for HbSC patients remain unclear. Recent NHLBI evidence-based guidelines highlight this as a critical knowledge gap, noting HbSC accounts for ∼30% of sickle cell patients within the United States. To date, only 5 publications have reported short-term, incomplete, or conflicting laboratory and clinical outcomes of hydroxyurea treatment in a total of 71 adults and children with HbSC. We now report on a cohort of 133 adult and pediatric HbSC patients who received hydroxyurea, typically for recurrent vaso-occlusive pain. Hydroxyurea treatment was associated with a stable hemoglobin concentration; increased fetal hemoglobin (HbF) and mean corpuscular volume (MCV); and reduced white blood cell count (WBC), absolute neutrophil count (ANC), and absolute reticulocyte count (ARC). Reversible cytopenias occurred in 22% of patients, primarily neutropenia and thrombocytopenia. Painful events were reduced with hydroxyurea, more in patients >15 years old. These multicenter data support the safety and potentially salutary effects of hydroxyurea treatment for HbSC disease; however, a multicenter, placebo-controlled, Phase 3 clinical trial is needed to determine if hydroxyurea therapy has efficacy for patients with HbSC disease.

Liver iron concentration measurements by MRI in chronically transfused children with sickle cell anemia: baseline results from the TWiTCH trial

Noninvasive, quantitative, and accurate assessment of liver iron concentration (LIC) by MRI is useful for patients receiving transfusions, but R2 and R2* MRI techniques have not been systematically compared in sickle cell anemia (SCA). We report baseline LIC results from the TWiTCH trial, which compares hydroxyurea with blood transfusion treatment for primary stroke prophylaxis assessed by transcranial Doppler sonography in pediatric SCA patients. Liver R2 was collected and processed using a FDA-approved commercial process (FerriScan®), while liver R2* quality control and processing were performed by a Core Laboratory blinded to clinical site and patient data. Baseline LIC studies using both MRI techniques were available for 120 participants. LICR2* and LICR2 results were highly correlated (r(2)  = 0.93). A proportional bias of LIC(R2*)/LIC(R2), decreasing with average LIC, was observed. Systematic differences between LICR2* and LICR2 were also observed by MRI manufacturer. Importantly, LICR2* and LICR2 estimates had broad 95% limits of agreement with respect to each other. We recommend LICR2 and LICR2* not be used interchangeably in SCA patients to follow individual patient trends in iron burden.

Abstract W P172: Baseline Quality of Life and Risk of Stroke in the Antihypertensive and Lipid Lowering to Prevent Heart Attack (ALLHAT) Trial

Background: Quality of Life (QoL) is an integrative health status measure that may predict medical outcomes. No prospective study assessed relationship between QoL, subsequent stroke risk, and post-stroke outcome.

Objective: Determine how baseline QoL predicted non-fatal stroke, as well as the impact of stroke risk factors on QoL in ALLHAT using visual analogue scale (VAS) – a validated QoL tool.

Methods: ALLHAT randomized hypertensive patients to Chlorthalidone (C), Amlodipine (A) or Lisinopril (L), and used VAS to measure global QoL (0.00 -1.00) at baseline, 2, 4, and 6 yrs. QoL values underwent statistical Torrance transformation (TQoL). Mean QoL and TQoL pre (baseline) and post non-fatal stroke were analyzed. Hazard ratios (HR) and Kaplan-Meier curves for each quartile of baseline QoL were calculated. Baseline QOL, TQoL, and stroke risk factors were used in a multiple linear regression model to predict post-stroke QoL. QoL changes were examined by study arm, age, gender, and race.

Results: 28,534 (86%) participants completed at least one VAS. Of the 1,517 strokes; 22% (n=322) were fatal. QoL and TQoL results were similar. Patients who experienced in-trial stroke in C and A arms had lower baseline QoL than those who did not (HR =.71 vs .74, p<0.001and .71 vs .74, p=0.004, respectively), but not in L (HR=.73 vs .74, p=0.24). A 10% increment in baseline QoL or TQoL was associated with 5% and 7% reduction in the risk of stroke respectively (adjusted HR; 95% CI = .95; .91 -.99) and .93; .89 –.98). In risk factor adjusted models, lowest baseline QoL quartile had a 20% higher stroke risk (HR =1.20; 95% CI: 1.00-1.44) than highest quartile. QoL worsened post stroke, dropping most in elderly >75 yrs (-.08 units, p<0.0001), compared to groups 55-64 (-.04, p<0.05) and 65-75 yrs, (-.07, p <0.0001), and in A arm (-.09 units, p<0.0001) compared with C (-.05, p=0.0006) and L (-.07, p< 0.0001), but did not differ by gender or race. In a multiple linear regression model, baseline QoL predicted post-stroke QoL.

Conclusions: Lower baseline QoL was associated with higher stroke risk. Qol was lower post stroke. Baseline QoL was the only factor predicting post stroke QoL, and QoL change increased with age. Investigation of factors determining QoL may be fertile ground for stroke risk reduction.

Getting clinical trial results into practice: design, implementation, and process evaluation of the ALLHAT Dissemination Project

BACKGROUND

Conventional dissemination of clinical trial results has inconsistent impact on physician practices. A more comprehensive plan to influence determinants of prescribing practices is warranted.

PURPOSE

To report the response from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial to the National Heart, Lung, and Blood Institute's requirement for dissemination and evaluation of trials with potential immediate public health applicability.

METHODS

ALLHAT's dissemination plan had two-components: (1) a traditional approach of media coverage, scientific presentation, and publication; and (2) a theory-based approach targeting determinants of clinician behavior. Strategies included: (1) academic detailing, in which physicians approach colleagues regarding blood pressure management, (2) direct patient messages to stimulate communication with physicians regarding blood pressure control, (3) approaches to formulary systems to use educational and economic incentives for evidence-based prescription, and (4) direct professional organization appeals to clinicians.

RESULTS

One hundred and forty-seven Investigator Educators reported 1698 presentations to 18,524 clinicians in 41 states and the District of Columbia. The pre- and post-test responses of 1709 clinicians in the face-to-face meetings indicated significant changes in expectations for positive patient outcomes and intention to prescribe diuretics. Information was mailed to 55 individuals representing 20 professional organizations and to eight formulary systems. Direct-to-patient messages were provided to 14 sites that host patient newsletters and Web sites such as health plans and insurance companies, 62 print mass media outlets, and 12 broadcast media sites.

LIMITATIONS

It was not within the scope of the project to conduct a randomized trial of the impact of the dissemination. However, impact evaluation using quasi-experimental designs is ongoing.

CONCLUSION

A large multi-method dissemination of clinical trial results is feasible. Planning for dissemination efforts, including evaluation research, should be considered as a part of the funding and design of the clinical trial and should begin early in trial planning.

Clinical outcomes by race in hypertensive patients with and without the metabolic syndrome: Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

BACKGROUND

Antihypertensive drugs with favorable metabolic effects are advocated for first-line therapy in hypertensive patients with metabolic/cardiometabolic syndrome (MetS). We compared outcomes by race in hypertensive individuals with and without MetS treated with a thiazide-type diuretic (chlorthalidone), a calcium channel blocker (amlodipine besylate), an alpha-blocker (doxazosin mesylate), or an angiotensin-converting enzyme inhibitor (lisinopril).

METHODS

A subgroup analysis of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), a randomized, double-blind hypertension treatment trial of 42 418 participants. We defined MetS as hypertension plus at least 2 of the following: fasting serum glucose level of at least 100 mg/dL, body mass index (calculated as weight in kilograms divided by height in meters squared) of at least 30, fasting triglyceride levels of at least 150 mg/dL, and high-density lipoprotein cholesterol levels of less than 40 mg/dL in men or less than 50 mg/dL in women.

RESULTS

Significantly higher rates of heart failure were consistent across all treatment comparisons in those with MetS. Relative risks (RRs) were 1.50 (95% confidence interval, 1.18-1.90), 1.49 (1.17-1.90), and 1.88 (1.42-2.47) in black participants and 1.25 (1.06-1.47), 1.20 (1.01-1.41), and 1.82 (1.51-2.19) in nonblack participants for amlodipine, lisinopril, and doxazosin comparisons with chlorthalidone, respectively. Higher rates for combined cardiovascular disease were observed with lisinopril-chlorthalidone (RRs, 1.24 [1.09-1.40] and 1.10 [1.02-1.19], respectively) and doxazosin-chlorthalidone comparisons (RRs, 1.37 [1.19-1.58] and 1.18 [1.08-1.30], respectively) in black and nonblack participants with MetS. Higher rates of stroke were seen in black participants only (RR, 1.37 [1.07-1.76] for the lisinopril-chlorthalidone comparison, and RR, 1.49 [1.09-2.03] for the doxazosin-chlorthalidone comparison). Black patients with MetS also had higher rates of end-stage renal disease (RR, 1.70 [1.13-2.55]) with lisinopril compared with chlorthalidone.

CONCLUSIONS

The ALLHAT findings fail to support the preference for calcium channel blockers, alpha-blockers, or angiotensin-converting enzyme inhibitors compared with thiazide-type diuretics in patients with the MetS, despite their more favorable metabolic profiles. This was particularly true for black participants.

The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases

Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.

Formation of specialized propagules resistant to desiccation and cryopreservation in the threatened moss Ditrichum plumbicola (Ditrichales, Bryopsida)

BACKGROUND AND AIMS

Successful cryopreservation of bryophytes is linked to intrinsic desiccation tolerance and survival can be enhanced by pre-treatment with abscisic acid (ABA) and sucrose. The pioneer moss Ditrichum plumbicola is naturally subjected to desiccation in the field but showed unexpectedly low survival of cryopreservation, as well as a poor response to pre-treatment. The effects of the cryopreservation protocol on protonemata of D. plumbicola were investigated in order to explore possible relationships between the production in vitro of cryopreservation-tolerant asexual propagules and the reproductive biology of D. plumbicola in nature.

METHODS

Protonemata were prepared for cryopreservation using a four-step protocol involving encapsulation in sodium alginate, pre-treatment for 2 weeks with ABA and sucrose, desiccation for 6 h and rapid freezing in liquid nitrogen. After each stage, protonemata were prepared for light and electron microscopy and growth on standard medium was monitored. Further samples were prepared for light and electron microscopy at intervals over a 24-h period following removal from liquid nitrogen and re-hydration.

KEY RESULTS

Pre-treatment with ABA and sucrose caused dramatic changes to the protonemata. Growth was arrested and propagules induced with pronounced morphological and cytological changes. Most cells died, but those that survived were characterized by thick, deeply pigmented walls, numerous small vacuoles and lipid droplets in their cytoplasm. Desiccation and cryopreservation elicited no dramatic cytological changes. Cells returned to their pre-dehydration and cryopreservation state within 2 h of re-hydration and/or removal from liquid nitrogen. Regeneration was normal once the ABA/sucrose stimulus was removed.

CONCLUSIONS

The ABA/sucrose pre-treatment induced the formation of highly desiccation- and cryopreservation-tolerant propagules from the protonemata of D. plumbicola. This parallels behaviour in the wild, where highly desiccation-tolerant rhizoids function as perennating organs allowing the moss to endure extreme environmental conditions. An involvement of endogenous ABA in the desiccation tolerance of D. plumbicola is suggested.

Cardiovascular outcomes in high-risk hypertensive patients stratified by baseline glomerular filtration rate

BACKGROUND

Chronic kidney disease is common in older patients with hypertension.

OBJECTIVE

To compare rates of coronary heart disease (CHD) and end-stage renal disease (ESRD) events; to determine whether glomerular filtration rate (GFR) independently predicts risk for CHD; and to report the efficacy of first-step treatment with a calcium-channel blocker (amlodipine) or an angiotensin-converting enzyme inhibitor (lisinopril), each compared with a diuretic (chlorthalidone), in modifying cardiovascular disease (CVD) outcomes in high-risk patients with hypertension stratified by GFR.

DESIGN

Post hoc subgroup analysis.

SETTING

Multicenter randomized, double-blind, controlled trial.

PARTICIPANTS

Persons with hypertension who were 55 years of age or older with 1 or more risk factors for CHD and who were stratified into 3 baseline GFR groups: normal or increased (> or = 90 mL/min per 1.73 m2; n = 8126 patients), mild reduction (60 to 89 mL/min per 1.73 m2; n = 18,109 patients), and moderate or severe reduction (< 60 mL/min per 1.73 m2; n = 5662 patients).

INTERVENTIONS

Random assignment to chlorthalidone, amlodipine, or lisinopril.

MEASUREMENTS

Rates of ESRD, CHD, stroke, and combined CVD (CHD, coronary revascularization, angina, stroke, heart failure, and peripheral arterial disease).

RESULTS

In participants with a moderate to severe reduction in GFR, 6-year rates were higher for CHD than for ESRD (15.4% vs. 6.0%, respectively). A baseline GFR of less than 53 mL/min per 1.73 m2 (compared with >104 mL/min per 1.73 m2) was independently associated with a 32% higher risk for CHD. Amlodipine was similar to chlorthalidone in reducing CHD (16.0% vs. 15.2%, respectively; hazard ratio, 1.06 [95% CI, 0.89 to 1.27]), stroke, and combined CVD (CHD, coronary revascularization, angina, stroke, heart failure, and peripheral arterial disease), but less effective in preventing heart failure. Lisinopril was similar to chlorthalidone in preventing CHD (15.1% vs. 15.2%, respectively; hazard ratio, 1.00 [CI, 0.84 to 1.20]), but was less effective in reducing stroke, combined CVD events, and heart failure.

LIMITATIONS

Proteinuria data were not available, and combination therapies were not tested.

CONCLUSIONS

Older high-risk patients with hypertension and reduced GFR are more likely to develop CHD than to develop ESRD. A low GFR independently predicts increased risk for CHD. Neither amlodipine nor lisinopril is superior to chlorthalidone in preventing CHD, stroke, or combined CVD, and chlorthalidone is superior to both for preventing heart failure, independent of level of renal function.

Clinical outcomes in antihypertensive treatment of type 2 diabetes, impaired fasting glucose concentration, and normoglycemia: Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

BACKGROUND

Optimal first-step antihypertensive drug therapy in type 2 diabetes mellitus (DM) or impaired fasting glucose levels (IFG) is uncertain. We wished to determine whether treatment with a calcium channel blocker or an angiotensin-converting enzyme inhibitor decreases clinical complications compared with treatment with a thiazide-type diuretic in DM, IFG, and normoglycemia (NG).

METHODS

Active-controlled trial in 31 512 adults, 55 years or older, with hypertension and at least 1 other risk factor for coronary heart disease, stratified into DM (n = 13 101), IFG (n = 1399), and NG (n = 17 012) groups on the basis of national guidelines. Participants were randomly assigned to double-blind first-step treatment with chlorthalidone, 12.5 to 25 mg/d, amlodipine besylate, 2.5 to 10 mg/d, or lisinopril, 10 to 40 mg/d. We conducted an intention-to-treat analysis of fatal coronary heart disease or nonfatal myocardial infarction (primary outcome), total mortality, and other clinical complications.

RESULTS

There was no significant difference in relative risk (RR) for the primary outcome in DM or NG participants assigned to amlodipine or lisinopril vs chlorthalidone or in IFG participants assigned to lisinopril vs chlorthalidone. A significantly higher RR (95% confidence interval) was noted for the primary outcome in IFG participants assigned to amlodipine vs chlorthalidone (1.73 [1.10-2.72]). Stroke was more common in NG participants assigned to lisinopril vs chlorthalidone (1.31 [1.10-1.57]). Heart failure was more common in DM and NG participants assigned to amlodipine (1.39 [1.22-1.59] and 1.30 [1.12-1.51], respectively) or lisinopril (1.15 [1.00-1.32] and 1.19 [1.02-1.39], respectively) vs chlorthalidone.

CONCLUSION

Our results provide no evidence of superiority for treatment with calcium channel blockers or angiotensin-converting enzyme inhibitors compared with a thiazide-type diuretic during first-step antihypertensive therapy in DM, IFG, or NG.

Renal outcomes in high-risk hypertensive patients treated with an angiotensin-converting enzyme inhibitor or a calcium channel blocker vs a diuretic: a report from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

BACKGROUND

This study was performed to determine whether, in high-risk hypertensive patients with a reduced glomerular filtration rate (GFR), treatment with a calcium channel blocker or an angiotensin-converting enzyme inhibitor lowers the incidence of renal disease outcomes compared with treatment with a diuretic.

METHODS

We conducted post hoc analyses of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Hypertensive participants 55 years or older with at least 1 other coronary heart disease risk factor were randomized to receive chlorthalidone, amlodipine, or lisinopril for a mean of 4.9 years. Renal outcomes were incidence of end-stage renal disease (ESRD) and/or a decrement in GFR of 50% or more from baseline. Baseline GFR, estimated by the simplified Modification of Diet in Renal Disease equation, was stratified into normal or increased (> or =90 mL /min per 1.73 m(2), n = 8126), mild reduction (60-89 mL /min per 1.73 m(2), n = 18 109), or moderate-severe reduction (<60 mL /min per 1.73 m(2), n = 5662) in GFR. Each stratum was analyzed for effects of the treatments on outcomes.

RESULTS

In 448 participants, ESRD developed. Compared with patients taking chlorthalidone, no significant differences occurred in the incidence of ESRD in patients taking amlodipine in the mild (relative risk [RR], 1.47; 95% confidence interval [CI], 0.97-2.23) or moderate-severe (RR, 0.92; 95% CI, 0.68-1.24) reduction in GFR groups. Compared with patients taking chlorthalidone, no significant differences occurred in the incidence of ESRD in patients taking lisinopril in the mild (RR, 1.34; 95% CI, 0.87-2.06) or moderate-severe (RR, 0.98; 95% CI, 0.73-1.31) reduction in GFR groups. In patients with mild and moderate-severe reduction in GFR, the incidence of ESRD or 50% or greater decrement in GFR was not significantly different in patients treated with chlorthalidone compared with those treated with amlodipine (odds ratios, 0.96 [P = .74] and 0.85 [P = .23], respectively) and lisinopril (odds ratios, 1.13 [P = .31] and 1.00 [P = .98], respectively). No difference in treatment effects occurred for either end point for patients taking amlodipine or lisinopril compared with those taking chlorthalidone across the 3 GFR subgroups, either for the total group or for participants with diabetes at baseline. At 4 years of follow-up, estimated GFR was 3 to 6 mL /min per 1.73 m(2) higher in patients assigned to receive amlodipine compared with chlorthalidone, depending on baseline GFR stratum.

CONCLUSIONS

In hypertensive patients with reduced GFR, neither amlodipine nor lisinopril was superior to chlorthalidone in reducing the rate of development of ESRD or a 50% or greater decrement in GFR. Participants assigned to receive amlodipine had a higher GFR than those assigned to receive chlorthalidone, but rates of development of ESRD were not different between the groups.

The Prevalence of Reduced Glomerular Filtration Rate in Older Hypertensive Patients and Its Association With Cardiovascular DiseaseA Report From the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial

BACKGROUND

The prevalence of reduced glomerular filtration rate (GFR) in older hypertensive patients and the relationship between level of GFR and cardiovascular disease (CVD) and its risk factors are not well known.

METHODS

We evaluated baseline renal function in 40 514 hypertensive patients 55 years or older who were enrolled in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). We used the simplified Modification of Diet in Renal Disease study equation to estimate GFR and examined the prevalence of CVD in patients with different levels of GFR.

RESULTS

Fifty-seven percent of patients had mild (60-89 mL/min per 1.73 m(2)), 17.2% had moderate (30-59 mL/min per 1.73 m(2)), and 0.6% had severe (<or=29 mL/min per 1.73 m(2)) reductions in GFR. Compared with patients with normal or mildly reduced GFR, patients with moderate or severe reductions in GFR were more likely to have had a prior myocardial infarction or stroke (19.2% and 23.4% vs 28.7% and 26.9%, respectively), have ischemic changes on electrocardiography (ECG) (16.0% and 18.9% vs 24.6% and 34.1%, respectively), and have left ventricular hypertrophy on ECG (ECG-LVH) (3.9% and 4.2% vs 6.0% and 11.2%, respectively). A decrease in GFR of 10 mL/min per 1.73 m(2) was independently associated with a 6% higher risk for CVD and 14% higher risk for ECG-LVH. The increase in risk was marked at a GFR of approximately 60 to 70 mL/min per 1.73 m(2).

CONCLUSIONS

The prevalence of reduced GFR is high in older hypertensive patients. Patients with moderate or severe reduction in GFR are more likely to have a history of CVD and ECG-LVH. Even modest reductions in GFR are independently associated with a higher prevalence of CVD and ECG-LVH.

The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT): clinical center recruitment experience

The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a randomized clinical outcome trial of antihypertensive and lipid-lowering therapy in a diverse population (including substantial numbers of women and minorities) of 42,419 high-risk hypertensives aged > or = 55 years with a planned mean follow-up of 6 years. In this paper, we describe our experience in the identification, recruitment, and selection of clinical centers for this large simple trial capable of meeting the recruitment goals outlined for ALLHAT, and we highlight factors associated with clinical center performance. Over 135,000 recruitment brochures were mailed to physicians. Requests for information and application packets were received from 9351 (6.8%) interested investigators. A total of 1053 completed applications were received and 909 sites (86%) were eventually approved to join the trial. Of the approved sites, 278 either later declined participation or were never activated, and 8 were closed within a year for lack of enrollment. The final 623 randomizing centers exceeded the trial's recruitment goal to enroll at least 40,000 participants into the trial, although the recruitment period was extended 1.5 years longer than planned. Fewer than a quarter of the sites (22.6%) were recruited from academic medical centers or Department of Veterans Affairs Medical Centers. More than half of the sites (54.7%) were private solo or group practices, which contributed 53% of randomized participants. Community health centers comprised about 8% of the ALLHAT sites and 2.9% were part of health maintenance organizations. More than 22% of the principal investigators reported that they had no previous clinical research experience. In summary, ALLHAT was successful in recruiting a diverse group of clinical centers to achieve its patient recruitment goals.

Participant recruitment in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a practice-based, randomized, multicenter clinical trial in 42,419 high-risk hypertensive patients aged 55 years and older; 10,356 of these patients are also in a lipid-lowering trial component. The purpose of the antihypertensive component is to determine whether the occurrence of fatal coronary heart disease and/or nonfatal myocardial infarction differs between patients randomized to diuretic (chlorthalidone) and those randomized to either calcium antagonist (amlodipine), angiotensin-converting enzyme inhibitor (lisinopril), or alpha-adrenergic blocker (doxazosin) therapy. (The doxazosin arm has been discontinued.) The purpose of the lipid-lowering component is to determine whether lowering low-density lipoprotein cholesterol with a 3-hydroxymethyl-glutaryl coenzyme A reductase inhibitor (pravastatin) in moderately hypercholesterolemic patients will reduce all-cause mortality compared to a control group receiving "usual care." ALLHAT recruited patients from a variety of practice settings from February 1994 through January 1998. Sites were paid for randomizations and are paid for completed follow-up visits and documented study events. Communication and monitoring were facilitated by nine regional coordinator teams. It was recognized from the outset that patient recruitment would be a very large task because of the number of participants (> 40,000) needed, the ambitious nature of the goal for recruitment of African-Americans (> 55%), and the knowledge that many investigators had limited experience recruiting participants for clinical trials. Multiple adjustments in the initial ALLHAT overall recruitment plan facilitated achievement of sample size goals for both components of the trial. The experience obtained from this large trial should be valuable for the planning and implementation of successful recruitment in future trials.

Effect of treating isolated systolic hypertension on the risk of developing various types and subtypes of stroke: the Systolic Hypertension in the Elderly Program (SHEP)

CONTEXT

The Systolic Hypertension in the Elderly Program (SHEP) demonstrated that treating isolated systolic hypertension in older patients decreased incidence of total stroke, but whether all types of stroke were reduced was not evaluated.

OBJECTIVE

To investigate antihypertensive drug treatment effects on incidence of stroke by type and subtype, timing of strokes, case-fatality rates, stroke residual effects, and relationship of attained systolic blood pressure to stroke incidence.

DESIGN

The SHEP study, a randomized, double-blind, placebo-controlled trial began March 1, 1985, and had an average follow-up of 4.5 years.

SETTING AND PARTICIPANTS

A total of 4736 men and women aged 60 years or older with isolated systolic hypertension at 16 clinical centers in the United States.

INTERVENTIONS

Patients were randomly assigned to receive treatment with 12.5 mg/d of chlorthalidone (step 1); either 25 mg/d of atenolol or 0.05 mg/d of reserpine (step 2) could be added (n = 2365); or placebo (n = 2371).

MAIN OUTCOME MEASURES

Occurrence, type and subtype, and timing of first strokes and stroke fatalities; and change in stroke incidence for participants (whether in active treatment or placebo groups) reaching study-specific systolic blood pressure goal (decrease of at least 20 mm Hg from baseline to below 160 mm Hg) compared with participants not reaching goal.

RESULTS

A total of 85 and 132 participants in the active treatment and placebo groups, respectively, had ischemic strokes (adjusted relative risk [RR], 0.63; 95% confidence interval [CI], 0.48-0.82); 9 and 19 had hemorrhagic strokes (adjusted RR, 0.46; 95% CI, 0.21-1.02); and 9 and 8 had strokes of unknown type (adjusted RR, 1.05; 95% CI, 0.40-2. 73), respectively. Four subtypes of ischemic stroke were observed in active treatment and placebo group participants, respectively, as follows: for lacunar, n = 23 and n = 43 (adjusted RR, 0.53; 95% CI, 0.32-0.88); for embolic, n = 9 and n = 16 (adjusted RR, 0.56; 95% CI, 0.25-1.27); for atherosclerotic, n = 13 and n = 13 (adjusted RR, 0. 99; 95% CI, 0.46-2.15); and for unknown subtype, n = 40 and n = 60 (adjusted RR, 0.64; 95% CI, 0.43-0.96). Treatment effect was observed within 1 year for hemorrhagic strokes but was not seen until the second year for ischemic strokes. Stroke incidence significantly decreased in participants attaining study-specific systolic blood pressure goals.

CONCLUSIONS

In this study, antihypertensive drug treatment reduced the incidence of both hemorrhagic and ischemic (including lacunar) strokes. Reduction in stroke incidence occurred when specific systolic blood pressure goals were attained. JAMA. 2000;284:465-471

Relation of low body mass to death and stroke in the systolic hypertension in the elderly program. The SHEP Cooperative Research Group

BACKGROUND

There are scant data on the effect of body mass index (BMI) (calculated as weight in kilograms divided by the square of height in meters) on cardiovascular events and death in older patients with hypertension.

OBJECTIVE

To determine if low body mass in older patients with hypertension confers an increased risk of death or stroke.

PATIENTS

Participants were 3975 men and women (mean age, 71 years) enrolled in 17 US centers in the Systolic Hypertension in the Elderly Program trial, a randomized, double-blind, placebo-controlled clinical trial of lowdose antihypertensive therapy, with follow-up for 5 years.

MAIN OUTCOME MEASURES

Five-year adjusted mortality and stroke rates from Cox proportional hazards analyses.

RESULTS

There was no statistically significant relation of death or stroke with BMI in the placebo group (P = .47), and there was a U- or J-shaped relation in the treatment group. The J-shaped relation of death with BMI in the treated group (P = .03) showed that the lowest probability of death for men was associated with a BMI of 26.0 and for women with a BMI of 29.6; the curve was quite flat for women across a wide range of BMIs. For stroke, men and women did not differ, and the BMI nadir for both sexes combined was 29, with risk increasing steeply at BMIs below 24. Those in active treatment, however, had lower death and stroke rates compared with those taking placebo.

CONCLUSIONS

Among older patients with hypertension, a wide range of BMIs was associated with a similar risk of death and stroke; a low BMI was associated with increased risk. Lean, older patients with hypertension in treatment should be monitored carefully for additional risk factors.

Clinical trial participant satisfaction: survey of SHEP enrollees. SHEP Cooperative Research Group. Systolic Hypertension in the Elderly Program

OBJECTIVE

The purpose of this study was to determine older persons' reasons for joining a clinical trial, and to provide data that could be useful in planning and carrying out clinical trials in older and minority populations.

DESIGN

A survey.

PARTICIPANTS

The sample included 4281 men and women 60 years of age or older who were randomized to the Systolic Hypertension in the Elderly Program (SHEP).

MEASUREMENTS

A 10-item satisfaction/attitude questionnaire was designed to evaluate (1) what personal benefits people expect from participation in this trial, (2) motivation for joining, and (3) satisfaction with clinic staff and operations. Each question had a response category asking for a measure of agreement, satisfaction, or importance.

RESULTS

The most important reasons for joining the clinical trial were to contribute to science (96%), improve the health of others (96%), and improve their own health (93%). Free medical care and social aspects were less important reasons to join. There were no differences by treatment assignment, but differences in reasons for joining SHEP by age, race, gender, and education were observed.

CONCLUSION

Older adults were enthusiastic about clinical trial participation. Recruitment, participant management strategies, and allocation of resources should consider the needs of specific patient groups.

Rationale and design for the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). ALLHAT Research Group

Are newer types of antihypertensive agents, which are currently more costly to purchase on average, as good or better than diuretics in reducing coronary heart disease incidence and progression? Will lowering LDL cholesterol in moderately hypercholesterolemic older individuals reduce the incidence of cardiovascular disease and total mortality? These important medical practice and public health questions are to be addressed by the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), a randomized, double-blind trial in 40,000 high-risk hypertensive patients. ALLHAT is designed to determine whether the combined incidence of fatal coronary heart disease (CHD) and nonfatal myocardial infarction differs between persons randomized to diuretic (chlorthalidone) treatment and each of three alternative treatments--a calcium antagonist (amlodipine), an angiotensin converting enzyme inhibitor (lisinopril), and an alpha-adrenergic blocker (doxazosin). ALLHAT also contains a randomized, open-label, lipid-lowering trial designed to determine whether lowering LDL cholesterol in 20,000 moderately hypercholesterolemic patients (a subset of the 40,000) with a 3-hydroxymethylglutaryl coenzyme A (HMG CoA) reductase inhibitor, pravastatin, will reduce all-cause mortality compared to a control group receiving "usual care." ALLHAT's main eligibility criteria are: 1) age 55 or older; 2) systolic or diastolic hypertension; and 3) one or more additional risk factors for heart attack (eg, evidence of atherosclerotic disease or type II diabetes). For the lipid-lowering trial, participants must have an LDL cholesterol of 120 to 189 mg/dL (100 to 129 mg/dL for those with known CHD) and a triglyceride level below 350 mg/dL. The mean duration of treatment and follow-up is planned to be 6 years. Further features of the rationale, design, objectives, treatment program, and study organization of ALLHAT are described in this article.

Change in depression as a precursor of cardiovascular events. SHEP Cooperative Research Group (Systoloc Hypertension in the elderly)

OBJECTIVE

To determine the relationship between increasing depressive symptoms and cardiovascular events or mortality.

DESIGN

Cohort analytic study of data from randomized placebo-controlled double-blind clinical trial of antihypertensive therapy. Depressive symptoms were assessed semi-annually with the Center for Epidemiological Studies-Depression (CES-D) scale during an average follow-up of 4.5 years.

SETTING

Ambulatory patients in 16 clinical centers of the Systolic Hypertension in the Elderly Program.

PATIENTS

Generally healthy men and women aged 60 years or older randomized to active antihypertensive drug therapy or placebo who were 70% white and 53% women and had follow-up CES-D scores and no outcome events during the first 6 months (N=4367).

MAIN OUTCOME MEASURES

All-cause mortality, fatal or nonfatal stroke, or myocardial infarction.

RESULTS

Baseline depressive symptoms were not related to subsequent events; however, an increase in depression was prognostic. Cox proportional hazards regression analyses with the CES-D scale as a time-dependent variable, controlling for multiple covariates, indicated a 25% increased risk of death per 5-unit increase in the CES-D score (relative risk [RR], 1.25;95% confidence interval [CI], 1.15 to 1.36). The RR for stroke or myocardial infarction was 1.18(95%CI,1.08 to 1.30). Increase in CES-D score was an independent predictor in both placebo and active drug groups, and it was strongest as a risk factor for stroke among women (RR,1.29;95%CI,1.07 to 1.34).

CONCLUSIONS

Among elderly persons, a significant and substantial excess risk of death and stroke or myocardial infarction was associated with an increase in depressive symptoms over time, which may be a marker for subsequent major disease events and warrants the attention of physicians to such mood changes. However, further studies of casual pathways are needed before wide-spread screening for depression in clinical practice is to be recommended.

Age, race, and gender variation in the utilization of coronary artery bypass surgery and angioplasty in SHEP. SHEP Cooperative Research Group. Systolic Hypertension in the Elderly Program

OBJECTIVE

To assess variability in the use of coronary artery bypass grafting (CABG) and percutaneous transluminal angioplasty (PTCA) in the Systolic Hypertension in the Elderly Program (SHEP) cohort with incident coronary heart disease (CHD) by age, sex, and race.

DESIGN

Retrospective analysis of a multicenter prospective cohort study.

SETTING

Community-based ambulatory population in academic centers.

PATIENTS

Among 4736 subjects initially enrolled in SHEP, there were 432 incident cases of CHD, excluding those patients who experienced rapid or sudden cardiac death.

MAIN OUTCOME MEASURE

Incident cases of CHD who underwent CABG or PTCA.

RESULTS

Of those participants > or = 60 and < 75 years of age, 7.3% underwent PTCA, compared with 3.9% of those > or = 75 years (P = 0.14). 15.4% of those < 75 underwent CABG surgery, compared with 7.8% of those 75 and older (P = 0.018). When both of these endpoints, CABG and PTCA, were combined, 22.4% of those < 75 underwent a procedure, while only 11.7% of the older cohort did (P = 0.005). Twenty-six percent of men underwent either CABG or PTCA, while only 9.1% of women did (P < 0.001). Of those < 75 years of age, 31.1% of men and 12.3% of women underwent CABG or PTCA (P < 0.001). In the 75 and older age category, 19.5% of men underwent these interventions, compared with 5.9% of women (P = 0.005). Active treatment group was significantly associated with decreased use of procedures in participants < 75 year old with CHD. Race, activity limitations, number of comorbid conditions, education level, marital status, employment status, and social support were not significantly associated with CABG or PTCA use. When the variables studied were entered into a logistic regression model, increased age and female sex remained independently associated with decreased CABG and PTCA use.

CONCLUSION

In the SHEP trial older patients and women, regardless of comorbid conditions, socioeconomic status, and social support, underwent less intensive cardiovascular interventions than did younger patients and men when they developed CHD.

Impact of the treatment of isolated systolic hypertension on behavioral variables. Results from the systolic hypertension in the elderly program

BACKGROUND

Little information has been published on the impact of antihypertensive medications on quality of life in older persons. Particular concern has existed that lowering systolic blood pressure in older persons might have adverse consequences on cognition, mood, or leisure activities.

METHODS

A multicenter double-blind randomized controlled trial was conducted over an average of 5 years' followup involving 16 academic clinical trial clinics. Participants consisted of 4736 persons (1.06%) selected from 447,921 screenees aged 60 years and older. Systolic blood pressure at baseline ranged from 160 to 219 mm Hg, while diastolic blood pressure was less than 90 mm Hg. Participants were randomized to active antihypertensive drug therapy or matching placebo. Active treatment consisted of 12.5 to 25 mg of chlorthalidone for step 1, while step 2 consisted of 25 to 50 mg of atenolol. If atenolol was contraindicated, 0.05 to 0.10 mg of reserpine could be used for the second-step drug. The impact of drug treatment on measures of cognitive, emotional, and physical function and leisure activities was assessed.

RESULTS

Our analyses demonstrate that active treatment of isolated systolic hypertension in the Systolic Hypertension in the Elderly Program cohort had no measured negative effects and, for some measures, a slight positive effect on cognitive, physical, and leisure function. The positive findings in favor of the treatment group were small. There was no effect on measures related to emotional state. Measures of cognitive and emotional function were stable in both groups for the duration of the study. Both treatment groups showed a modest trend toward deterioration of some measures of physical and leisure function over the study period.

CONCLUSIONS

The overall study cohort exhibited decline over time in activities of daily living, particularly the more strenuous ones, and some decline in certain leisure activities. However, mood, cognitive function, basic self-care, and moderate leisure activity were remarkably stable for both the active and the placebo groups throughout the entire study. Results of this study support the inference that medical treatment of isolated systolic hypertension does not cause deterioration in measures of cognition, emotional state, physical function, or leisure activities.

Statistical considerations in monitoring the Systolic Hypertension in the Elderly Program (SHEP)

The Systolic Hypertension in the Elderly Program (SHEP), a randomized, double-masked, placebo-controlled trial of 4736 persons, was designed to assess the efficacy of antihypertensive drug treatment to reduce the risk of fatal and nonfatal strokes among people age 60 and over with isolated systolic hypertension. The statistical method used in interim monitoring of results was conditional power (or stochastic curtailment). The findings did not become conclusive until near the completion of the trial, and therefore SHEP was continued to its scheduled closing date. The trial demonstrated a 36% reduction in the incidence of stroke in the active treatment group (P = .0003). In addition to evaluating overall efficacy of treatment, the monitoring process considered such other issues as nonstroke outcomes, lag time between first report of stroke and final confirmation of stroke diagnosis, consistency of results across subgroups, and completeness of follow-up. The purpose of this article is to review these factors with primary emphasis on the statistical aspects.

Effect of thiazide-based therapy on serum alkaline phosphatase. Hypertension Detection and Follow-up Group

This study reports a correlation of alkaline phosphatase (AP) with diastolic blood pressure (DBP), and a reduction of alkaline phosphatase after chlorthalidone therapy that reached a nadir at three years of therapy, then gradually returned toward, but not reaching, baseline values. The data is from the baseline examination and follow-up of 3928 initially untreated stepped-care patients in the Hypertension Detection and Follow-up Program. In multiple regression analysis, both age and DBP were significantly correlated with increased AP in males and females. After initiation of therapy with chlorthalidone, AP levels fell progressively until the third year, when they were reduced by 11 +/- 15 IU in the males and 14 +/- 15 IU in the females. The data are compatible with the interpretation that thiazide-induced reduction in urinary calcium excretion has led to a more positive calcium balance and reduction of bone turnover, and suggests that a beneficial effect of thiazide-based antihypertensive therapy could be decreased osteoporosis.

Is thiazide-produced uric acid elevation harmful? Analysis of data from the Hypertension Detection and Follow-up Program

Interaction of thiazide diuretics and the serum uric acid and creatinine levels was studied in 3693 stepped care participants in the Hypertension Detection and Follow-up Program not receiving treatment at baseline. Among men grouped into quartiles by their level of uric acid at baseline, the upper quartile (average uric acid, 7.7 mg/dL [458 mumol/L]) had an average serum creatinine level of 1.2 mg/dL (106 mumol/L) and the lowest quartile (uric acid, 4.9 mg/dL [291 mumol/L]) had an average serum creatinine level of 1.1 mg/dL (97 mumol/L). Similar findings were present in women. Therapy with chlorthalidone or other thiazide-type diuretics tended to increase levels of uric acid and creatinine, but the increase in both was less in the upper quartile than in the lower quartile. Among individuals who were prescribed uric acid-lowering drugs, the level of serum creatinine increased just as much as in those whose uric acid level was not pharmacologically lowered. Baseline uric acid level was a weak predictor of mortality in men; the introduction of an interaction term for creatinine suggested that this effect was primarily restricted to those with elevated levels of both uric acid and creatinine at baseline. Change in uric acid level at one year after therapy was inversely correlated with mortality in men. There were few episodes of gout (only 15 recorded in five years among 3693 participants at risk). These results suggest that neither the baseline uric acid level nor the change in uric acid level produced by therapy injures the kidney. These results suggest no reason to lower uric acid levels pharmacologically in the treated hypertensive patient who is not gouty. They leave unanswered whether there is a predictive value to baseline uric acid level not explainable by other correlated cardiovascular risk factors.

Prediction of response to sodium intervention for blood pressure control

In the Dietary Intervention Study of Hypertension (DISH) we found that patients formerly treated with drugs and assigned to sodium-reduction intervention were twice as likely to remain off medication for up to 56 weeks as were the controls assigned to no-diet intervention, after adjusting for covariates. Within the sodium-restriction group approximately 60% of 131 people were Intervention Successes (IS) (urinary sodium less than or equal to 100 mmol/day at 8 weeks). The rest were classed as Non-Intervention Successes (NIS). Of the IS group, 54% were responders (drug-free for at least 56 weeks), but about 56% of the NIS group also remained drug-free. Multiple logistics showed that no one factor was able to predict response among the IS. We conclude that the IS likely to respond to sodium reduction are not readily identifiable a priori. Furthermore, since both IS and NIS showed similar blood-pressure effects from the sodium-restriction regimen compared with controls, the questions arise: whether a factor other than sodium reduction affects the blood pressure response for the sodium-restriction group; or whether the measurement of sodium intake and excretion is sufficiently precise to distinguish compliers from non-compliers.

Systolic blood pressure as an independent predictor of mortality in the Hypertension Detection and Follow-up Program

The Hypertension Detection and Follow-up Program (HDFP) findings demonstrate the predictive value of baseline systolic blood pressure (SBP) and of pulse pressure (PB) in five-year mortality from all causes. Grouping participants into four SBP strata revealed an approximately two-fold increase in age-adjusted mortality rate from SBP stratum I to SBP stratum IV. This effect remained after the contributions of other risk factors were controlled by multivariate analysis. In contrast, baseline diastolic blood pressure (DBP) had little demonstrable effect on mortality in this particular population. The predictive power of pulse pressure was similar to that of SBP. The group mean SBP of every stratum fell progressively during the trial, the change being of greater magnitude in the stepped care (SC) group than in the referred care (RC) group. Also, the reduction in all-cause mortality associated with SC treatment was observed at all levels of baseline SBP. An analysis using life table regression with SBP as a time-dependent variable showed that the postrandomization reduction in SBP was a significant factor in reducing mortality. Similarly, reduced DBP was also contributory. Prospective studies are required to answer definitively the question of the efficacy of treatment of systolic hypertension. Nevertheless, the present analysis of the HDFP data, despite design limitations, supports the advisability of reducing elevated systolic blood pressure.

Ascertainment of vital status through the National Death Index and the Social Security Administration

Ascertainment of the vital status of individuals is of central importance to epidemiologic studies which monitor mortality as an end point. Utilizing identifying information collected in 1973-1974, the Hypertension Detection and Follow-up Program, a prospective, multicenter study, followed 25,362 individuals to determine eight-year mortality. In the most recent follow-up, there were 617 individuals whose vital status was not known. Available identifying information on these and on all 1,322 participants known to have died in 1979-1981 was submitted to the National Death Index (NDI) for possible confirmation of vital status. A subset of individuals who had Social Security numbers (490 lost to follow-up and 1,154 known deaths) was also submitted to the Social Security Administration (SSA). The NDI correctly identified 87.0% of the known deaths. Of the 1,154 known deaths (those with known Social Security numbers) submitted to both agencies, the NDI identified 93.1% and the SSA 83.6%. Significant variations by race and sex were noted in the identification rates, in part because of Social Security number discrepancies. False matches through the NDI matching process occurred for 10.4% of the known deaths. In the more restrictive SSA search, only 0.5% false matches resulted. For those lost to follow-up, vital status was ascertained in 57.1%. This paper describes the relative efficacy and attributes of the use of these systems to ascertain vital status.

Effective dietary intervention in hypertensives: sodium restriction and weight reduction

A Dietary Intervention Study of Hypertension (DISH) was undertaken to determine whether patients whose high blood pressure had been controlled pharmacologically for a period of more than 5 years could maintain that control with sodium restriction or weight reduction instead of drugs. Four hundred ninety-six patients, classified by degree of overweight, were randomly assigned into one of seven groups. Included were those who would be withdrawn from antihypertensive medication and receive intervention for either sodium restriction or weight reduction. After 8 weeks of intervention, an average reduction of 24-hour urinary sodium output from a baseline of 158 mEq to 106 mEq (p less than .001) and from 130 mEq to 96 mEq (p less than .01) was achieved for the overweight and nonoverweight groups, respectively. That decline was still maintained at 56 weeks. Dietary estimates, obtained by analysis of 3-day food records, underestimated urinary output by an average of 12%, with blacks more likely to underestimate than whites, and the overweight more likely to underestimate than the nonoverweight. An average 10-lb weight loss was achieved, with no difference between men and women. Weight declined for 32 weeks, then leveled off and was maintained up to 56 weeks, indicating that sodium intake modification can be accomplished faster than weight reduction. Modest sodium restriction and weight reduction are feasible and achievable in a free-living population and have a positive effect on control of hypertension.

Dietary therapy slows the return of hypertension after stopping prolonged medication

This study asks whether prolonged antihypertensive therapy will "cure" a substantial percent of rigorously treated hypertensive patients and whether nutritional change will add an antihypertensive effect and reduce the relapse rate. Of 584 eligible patients normotensive while receiving therapy, 496 were randomized into control and discontinued-medication groups with and without dietary intervention. At 56 weeks, 50% of those who were no longer receiving medication remained normotensive by study criteria. Randomization either to weight-loss group (mean loss of 4.5 kg [10 lb]) or to sodium-restriction group (mean reduction of 40 mEq/day) increased the likelihood of remaining without drug therapy, with an adjusted odds ratio of 2.17 for the sodium group and 3.43 for the weight group. Highest success rates were in the nonoverweight mild hypertensives with sodium restriction (78%) and the overweight mild hypertensives who were reducing their weight (72%). These data demonstrate that weight loss or sodium restriction, in hypertensives controlled for five years, more than doubles success in withdrawal of drug therapy.

Relation of serum vitamins A and E and carotenoids to the risk of cancer

Epidemiologic studies suggest that low carotene intake and low levels of serum retinol may be associated with an increased risk of cancer. Likewise, in some animal studies vitamin E has been associated with a reduced rate of induced cancers. Therefore, we measured retinol, retinol-binding protein, vitamin E (alpha-tocopherol), and total carotenoids in serum collected in 1973 from 111 participants in the Hypertension Detection and Follow-up Program who were free of cancer at the time but were diagnosed as having cancer during the subsequent five years. These measurements were compared with those in 210 controls who were matched for age, sex, race, and time of blood collection, and who remained free of cancer. Mean values for retinol were similar for cases and controls (67.3 and 68.7 micrograms per deciliter, respectively [95 per cent confidence limits for case-control difference, -6.7 to 3.5]). Values were also similar for retinol-binding protein (6.01 and 5.94 mg per deciliter [-0.42 to 0.56]), and carotenoids (114.5 and 111.6 micrograms per deciliter [-9.1 to 15.9]). The mean base-line retinol level in the 18 subjects with subsequent lung cancer was higher than that in their matched controls (79.0 vs. 71.4 micrograms per deciliter, -4.9 to 19.7). Serum vitamin E levels were somewhat lower in subjects who later had cancer than in controls (1.16 and 1.26 mg per deciliter, -0.22 to 0.02), in part because of the confounding effect of serum cholesterol levels (when adjusted for lipid levels, the case-control difference was -0.05 mg per deciliter; -0.17 to 0.07). These data do not support hypotheses relating intake or serum levels of antioxidant vitamins to a reduced cancer risk.

Prediagnostic serum selenium and risk of cancer

Selenium levels in serum samples collected in 1973 from 111 subjects in whom cancer developed during the subsequent 5 years were compared with those in serum samples from 210 cancer-free subjects matched for age, race, sex, and smoking history. The mean selenium level of cases (0.129 +/- SEM 0.002 micrograms/ml) was significantly lower than that of controls (0.136 +/- 0.002 micrograms/ml). The risk of cancer for subjects in the lowest quintile of serum selenium was twice that of subjects in the highest. Multivariate adjustment for geographical area and serum levels of lipids, vitamins A and E, and carotene, did not alter this relation. The association between low selenium level and cancer was strongest for gastrointestinal and prostatic cancers. Serum levels of vitamins A and E compounded the effect of low selenium; relative risks for the lowest tertile of selenium were 2.4 and 3.9 in the lowest tertiles of vitamins E and A, respectively.

Nosological coding of cause of death

Death certificates representing 766 decedents who had participated in the Hypertension Detection and Follow-up Program (1973-1979) at one of 14 US centers were given to three nosologists for purposes of coding underlying cause of death. Analyses examined interobserver variability among the three nosologists as well as intraobserver variability for each of the three nosologists. All three nosologists agreed on a three-digit International Classification of Diseases, Adapted (ICDA) code in 90.2% of the cases and at least two out of three agreed in 99.7% of the death certificates examined. Agreement rates improved when disease codes were collapsed into broader categories utilized in the Hypertension Detection and Follow-up Program. When particular disease classifications (e.g., cerebrovascular, ischemic heart disease, myocardial infarction, and neoplasms) were examined, three out of three agreement rates were highest for neoplasms (97.8%) and lowest for myocardial infarction (86.5%). Similarly, two out of three agreement was highest for neoplasms (98.5%) and lowest for myocardial infarction (88.0%). Intranosologist agreement rates were based on a recoded 20% sample of death certificates. Agreement rates for three-digit ICDA codes ranged from 94.8% to 96.1% for the three nosologists. The agreement rates for the general disease categories ranged from 96.7% to 97.4%.