Measures of body fatness and height in early and mid-to-late adulthood and prostate cancer: risk and mortality in The Pooling Project of Prospective Studies of Diet and Cancer

BACKGROUND

Advanced prostate cancer etiology is poorly understood. Few studies have examined associations of anthropometric factors (e.g. early adulthood obesity) with advanced prostate cancer risk.

PATIENTS AND METHODS

We carried out pooled analyses to examine associations between body fatness, height, and prostate cancer risk. Among 830 772 men, 51 734 incident prostate cancer cases were identified, including 4762 advanced (T4/N1/M1 or prostate cancer deaths) cases, 2915 advanced restricted (same as advanced, but excluding localized cancers that resulted in death) cases, 9489 high-grade cases, and 3027 prostate cancer deaths. Cox proportional hazards models were used to calculate study-specific hazard ratios (HR) and 95% confidence intervals (CI); results were pooled using random effects models.

RESULTS

No statistically significant associations were observed for body mass index (BMI) in early adulthood for advanced, advanced restricted, and high-grade prostate cancer, and prostate cancer mortality. Positive associations were shown for BMI at baseline with advanced prostate cancer (HR = 1.30, 95% CI = 0.95-1.78) and prostate cancer mortality (HR = 1.52, 95% CI = 1.12-2.07) comparing BMI ≥35.0 kg/m2 with 21-22.9 kg/m2. When considering early adulthood and baseline BMI together, a 27% higher prostate cancer mortality risk (95% CI = 9% to 49%) was observed for men with BMI <25.0 kg/m2 in early adulthood and BMI ≥30.0 kg/m2 at baseline compared with BMI <25.0 kg/m2 in early adulthood and BMI <30.0 kg/m2 at baseline. Baseline waist circumference, comparing ≥110 cm with <90 cm, and waist-to-hip ratio, comparing ≥1.00 with <0.90, were associated with significant 14%-16% increases in high-grade prostate cancer risk and suggestive or significant 20%-39% increases in prostate cancer mortality risk. Height was associated with suggestive or significant 33%-56% risks of advanced or advanced restricted prostate cancer and prostate cancer mortality, comparing ≥1.90 m with <1.65 m.

CONCLUSION

Our findings suggest that height and total and central adiposity in mid-to-later adulthood, but not early adulthood adiposity, are associated with risk of advanced forms of prostate cancer. Thus, maintenance of healthy weight may help prevent advanced prostate cancer.

Abstract PD6-05: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Kehm RD, Phillips K-A, Daly MB, Andrulis IL, Liao Y, Ma X, Zeinomar N, MacInnis RJ, Dite GS, John EM, Buys SS, Milne RL, Hopper JL, Terry MB. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD6-05.

Abstract P4-09-02: Validation of iPrevent using the prospective family study cohort (ProF-SC)

Background: iPrevent (https://www.petermac.org/iprevent) provides women with highly-tailored risk management information after first estimating their breast cancer (BC) risk using the established risk prediction models, IBIS and BOADICEA. iPrevent has an internal switching algorithm that governs which model is used for each woman, depending on her risk factor data (i.e. LCIS/atypical hyperplasia status, BRCA status, and cancer family history). This study assessed the calibration and discriminatory accuracy of the 10-year BC risk estimates provided by iPrevent. Methods: Subjects were 16,574 women in the ProF-SC, aged 18-70 years and without BC or bilateral mastectomy at recruitment. After 10 years follow-up, 655 women (4%) were diagnosed with invasive BC. A “batch mode” for iPrevent is not available, so the iPrevent-assigned cumulative 10-year invasive BC risks were calculated by entering self-reported risk factors at cohort entry into either the IBIS (10,169 women) or BOADICEA (6,405 women) software packages (according to the iPrevent switching algorithm). To assess calibration, the mean iPrevent-assigned risk was compared with the mean 10-year observed invasive BC incidence, using a chi-squared goodness-of-fit statistic for the whole cohort, and by quartiles of risk. To evaluate discriminatory accuracy, the overall area under the receiver operating characteristic curve (AUC) for the development of invasive BC within 10 years was computed. Data were censored at date of invasive or in situ BC diagnosis, bilateral mastectomy, death, loss to follow-up, or at 10 years of follow-up. Results: For the whole cohort, iPrevent assigned risk was well-calibrated – 690 expected BCs (E) 655 observed (O) (E/O=1.05, 95% CI: 0.98-1.14), although for women in the highest risk quartile, i.e. &gt;6% 10-year risk, E/O=1.19, 95% CI: 1.07-1.32. The AUC was 0.70, 95% CI: 0.68-0.72. Conclusions: iPrevent is well calibrated overall and has good discriminatory accuracy for predicting 10-year BC risk, thus justifying its clinical use.

Citation Format: Phillips K-A, Liao Y, Collins IM, Buchsbaum R, Weideman P, Bickerstaffe A, MacInnis RJ, kConFab Investigators, Cuzick J, Antoniou A, Andrulis IL, John EM, Daly MB, Buys SS, Hopper JL, Terry MB. Validation of iPrevent using the prospective family study cohort (ProF-SC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-09-02.

Abstract P6-09-04: Benign breast disease and breast cancer risk across the spectrum of familial risk using a prospective family study cohort (ProF-SC)

Background: Benign breast disease (BBD) is one of the strongest risk factors for breast cancer but it is unclear whether the strength of the association with BBD and breast cancers varies by breast cancer family history. Few studies of BBD enrich specifically for putative genetic factors by over-sampling based on family history let alone evaluate potential interactions with measures of underlying familial risk. The aim of this study was to evaluate how risk associated with BBD is modified by underlying familial risk so as to guide clinical management and risk assessment of women with BBD.

Methods: Using a prospective family study cohort of 17,154 women unaffected with breast cancer at baseline and followed by questionnaire at regular intervals, we examined the association between BBD and breast cancer risk using Cox Proportional Hazards models. We classified women as having BBD if they reported at baseline having been told by a doctor that they had BBD, such as a non-cancerous cyst or breast lump. We did not have information on histologic sub-type. We confirmed self-reported diagnosis of BBD with pathology reports in a subset of the New York cohort and found high agreement between self-reported and pathologically confirmed BBD (93.5%). We assessed multiplicative and additive interactions with underlying familial risk profile (FRP) defined as either fixed-time horizon of 1-year, or total lifetime risk, estimated from the Breast Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) model.

Results: During 176,756 person-years of follow-up (mean 10.2, maximum 23.7 years), we observed 968 incident breast cancers cases with an average age at diagnosis of 55.8 years and average age at enrollment into the cohort of 46.8 years. At baseline, 4,704 (27%) women reported having a previous diagnosis of BBD. Compared to women with no history of BBD, breast cancer risk was increased in women of all ages (HR: 1.37, 95% CI: 1.19,1.56), and in women up to age 45 years (using attained age models) (HR: 1.40, 95% CI: 1.01,1.93). In terms of recency of BBD, we found that the increased risk associated with BBD remained 21 years or more after the initial BBD diagnosis (HR: 1.37, 95% CI: 1.11, 1.68). We found no evidence for multiplicative interactions with FRP, which implies that the increase in absolute risk associated with BBD depends on a woman's FRP (Table 1).

Conclusions: Women with a history of BBD have an increased risk of breast cancer that multiplies their underlying familial risk (FRP). These results could prove to be valuable for risk counseling and clinical management.

Table 1: Cumulative Incidence of Breast Cancer to age 45, 55, and 65 by BBD and underlying FRP as measured by 10-year BOADICEA score.AgeNo BBD, &lt;3.4 %BBD, &lt;3.4%No BBD, ≥3.4%BBD, ≥3.4%454.6 (3.8, 5.6)6.1(4.7, 8.0)12.1 (10.2, 14.5)16.1 (13.1, 19.7)557.4 (6.3, 8.7)9.8 (7.5, 12.8)19.1 (16.6, 22.0)25.0 (21.7, 28.9)659.7 (8.2, 11.5)12.8 (9.9, 16.5)24.5 (21.8, 27.6)31.8 (28.3, 35.7)

Citation Format: Zeinomar N, Phillips KA, Liao Y, MacInnis RJ, Dite GS, Daly MB, John EM, Andrulis IL, Buys SS, Hopper JL, Terry MB. Benign breast disease and breast cancer risk across the spectrum of familial risk using a prospective family study cohort (ProF-SC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-09-04.

Abstract P6-09-01: Risk-reducing oophorectomy and breast cancer risk across the spectrum of familial risk using a prospective family study cohort (ProF-SC)

Background: Whether risk-reducing salpingo oophorectomy (RRSO) reduces breast cancer risk in addition to reducing ovarian cancer risk is controversial with some arguing that the previous evidence of a reduction in breast cancer risk from RRSO was due to bias. Evidence from independent prospective cohorts of high-risk women is needed to resolve this controversy.

Methods: Using a prospective family study cohort of 17,810 women unaffected with breast cancer at baseline, we examined the association between RRSO and breast cancer risk using Cox Proportional Hazards models. We compared results estimating RRSO as a non-time-dependent variable to results treating RRSO as a time-dependent variable, because failing to account for the time-varying nature of a covariate person- time prior to RRSO, should it exist, will incorrectly attribute the cancer-free person-time to RRSO. We separately examined the association with RRSO in BRCA1 and BRCA2 mutation carriers and non-carriers, and further performed gene-stratified analyses in women with BRCA1 and BRCA2 only. We also assessed multiplicative interactions with underlying familial risk profile (FRP), defined as total lifetime risk estimated from the Breast Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm (BOADICEA) model.

Results: During a median 10.7 years of follow-up (maximum 23.7 years), we observed 1,040 incident cases of breast cancer with an average age at diagnosis of 55.8 years and average age at enrollment into the cohort of 46.8 years. A total of 2434 (14%) women reported at baseline having a RRSO. We observed decreased risk of breast cancer associated with RRSO for both BRCA1(N= 650) and BRCA2(N=557) mutation carriers when RRSO was treated as a fixed covariate (HR= 0.60, 95% CI=0.40-0.92 and HR= 0.40, 95%CI = 0.23-0.69, respectively). In contrast, when we treated RRSO as a time-varying covariate, for both BRCA1 and BRCA2 carriers, we no longer observed a decreased risk for BRCA1 and BRCA2 carriers (HR= 1.67, 95% CI=1.05-2.67 and HR= 0.97, 95%CI = 0.53-1.80, respectively). There was no association between RRSO and breast cancer risk for non-carriers (N=16,603), whether we treated RRSO as a fixed or time varying covariate (HR= 0.88, 95% CI=0.72-1.08 and HR= 1.06, 95%CI = 0.85-1.30, respectively).

Conclusions: Our findings provide an independent replication that the reduced risk of breast cancer previously observed in BRCA1 and BRCA2 mutation carrier women may be from bias in counting person-time. Clinical management of high-risk women should counsel based on the reduced risk of ovarian cancer from RRSO, but not breast cancer.

Citation Format: Terry MB, Phillips KA, Daly MB, Andrulis IL, Liao Y, Ma X, Zeinomar N, MacInnis RJ, Dite GS, John EM, Buys SS, Hopper JL. Risk-reducing oophorectomy and breast cancer risk across the spectrum of familial risk using a prospective family study cohort (ProF-SC) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-09-01.

Novel associations between blood DNA methylation and body mass index in middle-aged and older adults

BACKGROUND/OBJECTIVES

There is increasing evidence of a relationship between blood DNA methylation and body mass index (BMI). We aimed to assess associations of BMI with individual methylation measures (CpGs) through a cross-sectional genome-wide DNA methylation association study and a longitudinal analysis of repeated measurements over time.

SUBJECTS/METHODS

Using the Illumina Infinium HumanMethylation450 BeadChip, DNA methylation measures were determined in baseline peripheral blood samples from 5361 adults recruited to the Melbourne Collaborative Cohort Study (MCCS) and selected for nested case-control studies, 2586 because they were subsequently diagnosed with cancer (cases) and 2775 as controls. For a subset of 1088 controls, these measures were repeated using blood samples collected at wave 2 follow-up, a median of 11 years later; weight was measured at both time points. Associations between BMI and blood DNA methylation were assessed using linear mixed-effects regression models adjusted for batch effects and potential confounders. These were applied to cases and controls separately, with results combined through fixed-effects meta-analysis.

RESULTS

Cross-sectional analysis identified 310 CpGs associated with BMI with P<1.0 × 10^-7, 225 of which had not been reported previously. Of these 225 novel associations, 172 were replicated (P<0.05) using the Atherosclerosis Risk in Communities (ARIC) study. We also replicated using MCCS data (P<0.05) 335 of 392 associations previously reported with P<1.0 × 10^-7, including 60 that had not been replicated before. Associations between change in BMI and change in methylation were observed for 34 of the 310 strongest signals in our cross-sectional analysis, including 7 that had not been replicated using the ARIC study.

CONCLUSIONS

Together, these findings suggest that BMI is associated with blood DNA methylation at a large number of CpGs across the genome, several of which are located in or near genes involved in ATP-binding cassette transportation, tumour necrosis factor signalling, insulin resistance and lipid metabolism.

Study protocol for a natural experiment in a lower socioeconomic area to examine the health-related effects of refurbishment to parks including built-shade (ShadePlus)

INTRODUCTION

Parks in disadvantaged suburbs often have low quality and few amenities, which is likely to result in them being underutilised for recreation and physical activity. Refurbishment of parks, including shade, walking paths and other amenities, may have broad health-related benefits.

METHODS AND ANALYSIS

The study design, methods and planned analyses for a natural experiment examining the effects of refurbishments including built-shade added to parks in disadvantaged outer suburbs of Melbourne are described. Three intervention parks and three comparison parks matched for equivalence of park and neighbourhood characteristics were selected. Using mixed methods, the outcomes will be assessed during three consecutive spring-summer periods (T1: 2013-2014; T2: 2014-2015: T3: 2015-2016). Primary outcomes included: observed park use, physical activity and shade use. Self-reported social connectedness, community engagement and psychological well-being were assessed as secondary outcomes.

ETHICS AND DISSEMINATION

This study was approved by Cancer Council Victoria's Human Research Ethics Committee. Studies such as ShadePlus can improve understanding of the broader effects of park refurbishments (including physical activity levels and sun protection behaviours, as well as social connectedness and psychological well-being). The study findings will be disseminated through established urban planning and parks and recreation networks, peer review publications and conference presentations.

Abstract P2-06-01: Non-genetic risk factors improve accuracy of breast cancer risk assessment for women at high familial risk: Comparison of risk estimation models using the prospective family study cohort (ProF-SC)

This abstract was withdrawn by the authors.

The Influence of Age the BMI and All-Cause Mortality Association: A Meta-Analysis

OBJECTIVES

To assess BMI range with the lowest mortality for those aged <65 years and those ≥65 years, utilising cohort studies that spanned the entire adult age range.

DESIGN

A two-stage random effects meta-analysis of studies that reported mortality in cohorts both ≥65 years and <65 years. Setting / Participants: Community living adults aged ≥65 and <65 years.

RESULTS

Eight studies were included with a total of 370 416 subjects (306 340 aged <65 years; 64 076 ≥65 years). In the older age group, mortality risk increased at BMIs lower than 22 (BMI range 21.0-21.9: hazard ratio (HR) (95% confidence interval (CI)): 1.05 (1.03, 1.07)), which was not seen in younger adults. In the younger group, mortality increased from BMI range 28.0-28.9 (HR (95% CI): 1.13 (1.00, 1.29)), but mortality did not tend to increase significantly in the older group at BMIs above 23.

CONCLUSION

The recommended healthy weight range is appropriate for younger and middle aged adults but a higher BMI range should be recommended for older adults based on mortality.

Presence and potential for horizontal transfer of antibiotic resistance in oxidase-positive bacteria populating raw salad vegetables

To assess whether domestically grown fresh salad vegetables constitute a possible reservoir of antibiotic resistance for Canadian consumers, aerobic bacteria capable of forming colonies at 30 degrees C on nutrient-limited media were recovered from a single sampling of Romaine lettuce, Savoy spinach and alfalfa sprouts, then examined for their susceptibility to ten antibiotics and the carriage of potentially mobile R-plasmids and integrons. Of the 140 isolates resistant to one or more antibiotic, 93.5 and 90.0% were resistant to ampicillin and cephalothin; 35.7% to chloramphenicol, 10.0% to streptomycin, 4.2% to nalidixic acid, 4.2% to kanamycin, and 2.8% to gentamicin. Gram-positive isolates accounted for less than 4% of the antibiotic resistant strains. A small portion (23.1%) of the predominant oxidase-positive, gram-negative isolates was resistant to two or more antimicrobials. Members of the Pseudomonas fluorescens/putida complex were most prevalent among the 34 resistant strains identified. Sphingobacterium spp. and Acinetobacter baumanni also were detected. Ten of 52 resistant strains carried plasmids, 3 of which were self-transmissible and bore resistance to ampicillin and kanamycin. Eighteen of 48 gave PCR evidence for integron DNA. Class 2 type integrons were the most prevalent, followed by class 1. We conclude that the foods examined here carry antibiotic resistant bacteria at the retail level. Further, our determination that resistant strains contain integron-specific DNA sequences and self-transmissible R-plasmids indicates their potential to influence the pool of antibiotic resistance in humans via lateral gene transfer subsequent to ingestion.

A comparison of estradiol levels between women with a hysterectomy and ovarian conservation and women with an intact uterus

OBJECTIVES

To compare the distribution of estradiol levels between women with a hysterectomy and ovarian conservation and women with an intact uterus.

METHODS

A large cross-sectional study of women aged between 40 and 69 years, residing in Melbourne, Australia. Estradiol levels were available for 152 women with a hysterectomy and ovarian conservation and 1423 women with an intact uterus. All of the women were 'never-users' of hormone replacement therapy.

RESULTS

For women under 55 years of age, we observed that those with a hysterectomy and ovarian conservation had slightly higher estradiol levels compared with those with an intact uterus after adjustment for age, body mass index, smoking status and alcohol intake (ratio of geometric means of estradiol levels = 1.24; 95% confidence interval = 1.00-1.53). For women who were 55 years or greater, the distribution of estradiol levels varied little by hysterectomy status.

CONCLUSIONS

Our data do not suggest that women with hysterectomy and ovarian conservation have markedly different estradiol levels compared to women with an intact uterus.

Determinants of bone density in 30- to 65-year-old women: a co-twin study

Reported effects of body composition and lifestyle on bone mineral density in pre-elderly adult women have been inconsistent. In a co-twin study, we measured bone mineral density, lean and fat mass, and lifestyle factors. Analyzing within pair differences, we found negative associations between bone mineral density and tobacco use (2.3-3.3% per 10 pack-years) and positive associations with sporting activity and lean and fat mass.

INTRODUCTION

Reported effects of body composition and lifestyle of bone mineral density in pre-elderly adult women have been inconsistent.

METHODS

In a co-twin study of 146 female twin pairs aged 30 to 65 years, DXA was used to measure bone mineral density at the lumbar spine, total hip, and forearm, total body bone mineral content, and lean and fat mass. Height and weight were measured. Menopausal status, dietary calcium intake, physical activity, current tobacco use, and alcohol consumption were determined by questionnaire. Within-pair differences in bone measures were regressed through the origin against within-pair differences in putative determinants.

RESULTS

Lean mass and fat mass were associated with greater bone mass at all sites. A discordance of 10 pack-years smoking was related to a 2.3-3.3% (SE, 0.8-1.0) decrease in bone density at all sites except the forearm, with the effects more evident in postmenopausal women. In all women, a 0.8% (SE, 0.3) difference in hip bone mineral density was associated with each hour per week difference in sporting activity, with effects more evident in premenopausal women. Daily dietary calcium intake was related to total body bone mineral content and forearm bone mineral density (1.4 +/- 0.7% increase for every 1000 mg). Lifetime alcohol consumption and walking were not consistently related to bone mass.

CONCLUSION

Several lifestyle and dietary factors, in particular tobacco use, were related to bone mineral density. Effect sizes varied by site. Characterization of determinants of bone mineral density in midlife and thereafter may lead to interventions that could minimize postmenopausal bone loss and reduce osteoporotic fracture risk.

A PCR-RFLP method to identify the RN– gene in retailed pork chops

The RN– phenotype in swine is associated with an increase in muscle glycogen. The increased glycogen leads to increased drip and cooking loss and inferior ham quality. RN– type pork was usually identified by a biochemical measure of glycolytic potential (GP), which is an estimated sum of 2(glycogen, glucose, glucose-6-phosphate) + lactate. Recently, a mutation in the PRKAG3 gene was reported to be the cause of the dominantly inherited RN– phenotype. This note describes a new BsrB1 PCR-RFLP technique used to rapidly identify the PRKAG3 mutation and its correlation with biochemical markers for RN– type pork. The PRKAG3 BsrB1 mutation was not found in 27% of retail pork chop samples that had high GP values. Key words: Pigs, RN–, PRKAG3, glycogen potential.

Prolonged dietary treatment with conjugated linoleic acid stimulates porcine muscle peroxisome proliferator activated receptor gamma and glutamine-fructose aminotransferase gene expression in vivo

Peroxisome proliferator activated receptors (PPARs) represent a family of DNA binding proteins that are activated by a variety of dietary and endogenous fatty acids. The PPAR proteins are expressed throughout the body and are the target of a variety of lipidaemic and insulin sensitizing drugs. Conjugated linoleic acid (CLA) is a collective name for octadecadienoic acid isomers with conjugated double bonds, which can also act as ligands for some of the PPAR family. To gain better understanding of the long-term effects of PPAR activation, CLA was fed at 11 g/kg of feed for 45 days to castrated male pigs (barrows). These barrows had a significant repartitioning of subcutaneous fat to lean tissue in the carcass: fat was reduced by 9 x 2% and lean muscle was increased by 3 x 5%, but intramuscular fat content was also increased by 14% (P<0 x 05). PPARgamma, glutamine-fructose aminotransferase (GFAT), adipocyte fatty acid binding protein (AFABP), but not PPARalpha mRNA levels were significantly increased (P<0 x 05) in the CLA-fed pigs. The increased expression of PPARgamma and AFABP indicates that CLA induced the development of preadipocytes from stromal-vascular (s-v) stem cells to promote intramuscular fat content. The increase in the expression of GFAT mRNA indicates that the glucose supply of the muscle cells had been increased with the CLA diet, possibly sparing intramuscular fatty acid reserves.

Association of birth weight and current body size to blood pressure in female twins

It has been proposed that low birth weight is associated with high levels of blood pressure in later life. The aim of this study was to assess the relationship of blood pressure to birth weight and current body size during growth and adulthood. A total of 711 female multiple births, with one group of 244 in their growth phase mean age 12.0 (2.3)(SD) years and the other of 467 adults (mean age 35.2 (12.6) years), had height, weight and both systolic (SBP) and diastolic (DBP) blood pressures measured, and self-reported their birth weight. Regression analyses were performed to assess the cross-sectional and within-pair associations of blood pressure to birth weight, with and without adjustments for current body size. Within-pair analysis was based on 296 twin pairs. Cross-sectionally, a reduction in birth weight of 1 kg was associated with 2 to 3 mm Hg higher age-adjusted SBP, which was of marginal significance and explained about 2% of the population variance. Adjustment for body mass index did not significantly change this association. Within-pair analyses found no association between birth weight and SBP or DBP,even after adjusting for current body size. After age, current body size was the strongest predictor of systolic BP. The weak association of blood pressure to birth weight cross-sectionally is of interest, but any within-pair effect of birth weight on blood pressure must be minimal compared with the effect of current body size.

ACE inhibitors, beta-blockers, calcium blockers, and diuretics for the control of systolic hypertension

The objective of this study was to determine which of the common groups of antihypertensive drugs is most effective at lowering systolic blood pressure (SBP) in elderly patients with previously untreated hypertension and the percentage of patients controlled with single or sequential monotherapy. Subjects were recruited from patients attending other outpatient clinics and entered into the study if their SBP was more than 150 mm Hg after three visits. Patients were given a low and high dose of each of the main classes of drugs or placebo for 1 month each. The study was a balanced, randomized crossover design with five periods: placebo; angiotensin converting enzyme inhibitors; beta-blocking drugs; calcium-blocking drugs; and thiazide diuretics. Blood pressure (BP) was measured 24 to 26 h after the previous dose. A questionnaire for side effects was administered at each visit. Seventy-four patients entered the study. beta-Blockers could not be used in 15 patients because of asthma or bronchospasm and these had two placebo periods. There were 9 of 66 patients on P, 9 of 46 on beta-blockers, 4 of 65 on calcium-blocking drugs, 4 of 65 on diuretic, and 1 of 62 patients on ACE inhibitors who did not progress to the higher dose because of side effects. Decreases in SBP compared to randomized placebo were calcium-blocking drugs 15 mm Hg = diuretic 13 mm Hg > ACE inhibitors 8 mm Hg = beta-blockers 5 mm Hg. Blood pressure decrease correlated with placebo BP (P < .0005, r = 0.53 to 0.70). When corrected for placebo, target SBP (<140 mm Hg) was reached in between 6% to 15% of patients on monotherapy. Sequential monotherapy achieved target in 29%. Angiotensin converting enzyme inhibitors, calcium-blocking drugs, and diuretics had no more side effects than placebo. Patients on beta-blockers had more side effects and the well-being score was reduced. Diuretics and calcium-blocking drugs are more effective in elderly patients at lowering SBP pressure. beta-Blockers were relatively ineffective, were frequently contraindicated, and had more side effects. Monotherapy achieved control in only a small number of patients. In elderly people with essential hypertension, therapy should be instituted with diuretics or calcium-blocking drugs, but combination therapy will usually be required to achieve goal.