Initial non-compliance with antihypertensive monotherapy is followed by complete discontinuation of antihypertensive therapy

PURPOSE: Discontinuation with treatment is a major problem in the treatment of hypertension. The objective of our study was to assess the association between non-compliance and discontinuation in patients who started using antihypertensive monotherapy. METHODS: A nested case-control study within a cohort of new users of antihypertensive drugs between 1st January 1999 and 31st December 2002 was performed. We used data from the PHARMO database, a record linkage system containing drug-dispensing records from community pharmacies and linked hospital discharge records of approximately 950,000 subjects. Cases discontinued their use of antihypertensive monotherapy and were not switched to other antihypertensive treatment, controls stayed on their initially prescribed monotherapy. Conditional logistic regression was used to calculate odds ratios (OR) and their 95% confidence intervals (CI). RESULTS: In a cohort of 39,714 new users of antihypertensive drugs, we identified 9111 cases and 9111 matched controls. The percentage of non-compliant patients (compliance < 80%) among cases and controls was 14.0% and 5.8%, respectively [OR 2.86 (95%CI: 2.52-3.24)]. Patients who used less than 90 days had a higher risk on discontinuation [OR 3.10 (95%CI: 2.67-3.59)] than patients who used more than 90 days [OR 2.28 (95%CI: 1.79-2.92)]. The association was generally similar among males and females, among the different types of antihypertensives and among the different age groups. CONCLUSION: In patients who start antihypertensive monotherapy, non-compliance is often followed by discontinuation of this antihypertensive treatment. The pharmacy medication history is a valuable tool for physicians to identify patients who have a high risk on discontinuation with antihypertensive treatment.     

Alcohol consumption, glutathione S-transferase M1 and T1 genetic polymorphisms and breast cancer risk

To evaluate the potential association between GSTM1 and GSTT1 genotypes and development of breast cancer, a hospital based case-control study was conducted in a South Korean study population consisting of 189 histologically confirmed incident breast cancer cases and their 189 age-matched control subjects with no present or previous history of cancer. A multiplex polymerase chain reaction method was used for the genotyping analyses and statistical evaluations were performed by unconditional logistic regression model. The GSTM1 null genotype was significantly associated with breast cancer risk in premenopausal women [odds ratio (OR) = 2.0, 95% confidence interval (CI) = 1-3.7], but not in the postmenopausal women (OR = 0.9, 95% CI = 0.5-1.9), nor in all women grouped together (OR = 1.3, 95% CI = 0.8-1.1). The GSTT1 null genotype posed a similar risk of breast cancer with an OR of 1.6 (95% CI = 1.0-2.5) for the total breast cancer group, OR of 1.7 (95% CI = 0.9-3.2) for pre-menopausal women, and OR of 1.3 (95% CI = 0.6-2.8) for post-menopausal women. The breast cancer risk associated with concurrent lack of both GSTM1 and GSTT1 genes was 2.2 (95% CI = 1.1-4.5), and the risk increased as the number of null genotype increased (P for trend = 0.03). When the data were stratified by the known risk factors of breast cancer, a significant interaction was observed between the GSTM1 genotypes and alcohol consumption (P for interaction = 0.03). An especially remarkable risk of breast cancer was observed for alcohol-consuming premenopausal women lacking both the GSTM1 and GSTT1 genes (OR = 5.3, 95% CI = 1.0-27.8) compared to those with both of the genes. Our findings thus suggest a novel gene-environment interaction which plays an important role in the individual susceptibility to breast cancer. p6     

The use of folic acid antagonists and the risk of colorectal cancer

PURPOSE: Since folate is associated with a reduced risk of colorectal cancer, we hypothesized that folic acid antagonists might increase the risk. We used data from a population-based case control study of medication use and colorectal cancer to evaluate the hypothesis. METHODS: Case patients with adenocarcinoma of the colon or rectum were ascertained from participating hospitals in Massachusetts and the Massachusetts cancer registry (MCR) from January 1, 2001, through November 30, 2004. Age-, sex-, and precinct-matched control subjects were chosen from Massachusetts town lists. Information on folic acid antagonist use and other relevant data were obtained from 1809 cases and 1809 matched controls by telephone interview and by a self-administered dietary questionnaire. We used logistic regression models to estimate odds ratios among 1229 case patients and 1165 control subjects who provided satisfactory dietary information and did not have Crohn's disease or ulcerative colitis. RESULTS: The odds ratio for colorectal cancer among regular users of folate-containing supplements was 0.7 (95%CI 0.6-0.9). The odds ratio for regular use of folic acid antagonists was 1.3 (95%CI 0.9-1.9). Contrary to expectation, the odds ratio was reduced in the highest category of alcohol consumption (OR = 0.5, 95%CI 0.2-1.2). The odds ratio was higher among users of drugs that inhibit dihydrofolate reductase (OR = 1.6, 95%CI 0.9-2.8) than drugs that work through other mechanisms (OR = 1.2, 95%CI 0.7-1.9). CONCLUSIONS: Our data provide little support for the hypothesis that regular folic acid antagonist use increases the risk of colorectal cancer. However, there is a suggestion that dihydrofolate reductase inhibitors specifically may increase the risk.     

Vitamin D receptor gene polymorphism as an important modifier of positive family history related breast cancer risk

The association between vitamin D receptor (VDR) gene polymorphisms and diseases such as breast cancer, prostate cancer and osteoporosis has been extensively investigated during recent years. To date, several polymorphisms have been found in the VDR gene. In this Finnish case-control study, comprising 483 breast cancer patients and 482 healthy population controls, we investigated the association between altered breast cancer risk and two polymorphisms in the 3' end of the gene detectable with ApaI and TaqI restriction enzymes. A statistically significant difference was observed in the ApaI genotype distribution between cases and controls. Women with the VDR variant a allele containing genotypes showed a decreased risk for breast cancer [odds ratio (OR) 0.73, 95% confidence interval (CI) 0.54-0.98] compared to women with the AA genotype. This association was especially strong among women with a positive family history of breast cancer (OR 0.14, 95% CI 0.03-0.76). Moreover, there was a trend (P for trend = 0.0007) for decreased risk with increasing number of variant alleles. The lowest risk of breast cancer was seen for the women with the aa genotype (OR 0.03, 95% CI 0.003-0.31) compared to women with the AA genotype. A tendency of decreased risk of breast cancer was also observed for the TaqI T allele containing genotypes (Tt and TT) (OR 0.68, 95% CI 0.41-1.12), but because the distribution of Taql alleles in the controls missed the Hardy-Weinberg equilibrium (P = 0.01), we were unable to properly assess the potential impact of the TaqI polymorphism in breast cancer susceptibility. In conclusion, our results suggest that the VDR ApaI genotype may be an important modifier of individual breast cancer risk among Finnish women, especially if they have a positive family history of breast cancer.     

NAT2 slow acetylation and GSTM1 null genotypes may increase postmenopausal breast cancer risk in long-term smoking women

N-acetyltransferase (NAT) 1 and 2 and glutathione S-transferase (GST) M1 and T1 are phase II enzymes that are important for activation and detoxification of carcinogenic heterocyclic and aromatic amines, as present in cigarette smoke. We studied whether genetic polymorphisms in these genes modifies the relationship between smoking and breast cancer. A nested case-control study was conducted among participants in a Dutch prospective cohort. Breast cancer cases (n=229) and controls (n=264) were frequency-matched on age, menopausal status and residence. Compared to never smoking, smoking 20 cigarettes or more per day increased breast cancer risk statistically significant only in postmenopausal women [odds ratio (OR)=2.17; 95% confidence interval (CI) 1.04-4.51]. Neither NAT1 slow genotype, or GSTT1 null genotype, alone or in combination with smoking, affected breast cancer risk. However, compared to individuals with rapid NAT2 genotype, women with the very slow acetylator genotype (NAT2*5), who smoked for 20 years showed an increased breast cancer risk (OR=2.29; 95% CI 1.06-4.95). Similarly, the presence of GSTM1 null genotype combined with high levels of cigarette smoking (OR=3.00; 95% CI 1.46-6.15) or long duration (OR=2.53; 95% CI 1.24-5.16), increased rates of breast cancer. The combined effect of GSTM1 null genotype and smoking high doses was most pronounced in postmenopausal women (OR=6.78; 95% CI 2.31-19.89). In conclusion, our results provide support for the view that women who smoke and who have a genetically determined reduced inactivation of carcinogens (GSTM1 null genotype or slow NAT2 genotype (especially very slow NAT2 genotype)) are at increased risk of breast cancer.     

Serum levels of polychlorinated biphenyls in Mexican women and breast cancer risk

The most prevalent female cancer across the world is breast cancer. Current established breast cancer risk factors explain only a fraction of the breast cancer cases diagnosed, and for this reason, other environmental factors have been studied. Exposure to organochlorine compounds has been linked to an increased incidence of breast cancer, although not all data have been consistent. This study was designed to evaluate the relation between polychlorinated biphenyls (PCB) exposure and breast cancer risk in Mexican women. We recruited 140 women from the General Hospital. The cases were 70 newly diagnosed women. We collected environmental and reproductive information by questionnaire. Blood samples were taken for measurement of serum levels of 20 PCB congeners. Risk of breast cancer was found to be positively associated with heavy congeners, age, postmenopausal status, family history of breast cancer and living close to an industrial facility. When PCB were grouped by structure–activity relationships, the risk of breast cancer was positively associated with groups 2b (odds ratio, OR = 1.90, 95% confidence interval, CI, 1.25–2.88), 3 (OR = 1.81, 95% CI 1.08–3.04) and group 4 (OR = 1.57, 95% CI 1.20–2.07). Among postmenopausal women, PCB levels from groups 1a, 2b, and 4 and total PCB were higher in cases, and an association between risk of breast cancer with groups 1a (OR = 7.59, 95% CI 1.1–51.4), 2b (OR = 3.7, 95% CI 1.2–11.2) and 4 (OR = 1.8, 95% CI 1.1–3.1) was found in this group of women. This study showed an association between heavy and potentially estrogenic PCB congeners and breast cancer risk. Copyright © 2011 John Wiley & Sons, Ltd.     

Effectiveness of statins in the reduction of the risk of myocardial infarction is modified by the GNB3 C825T variant

INTRODUCTION: The GNB3 C825T polymorphism has been shown to affect lipid parameters, atherosclerosis progression, and incidence of myocardial infarction (MI). Therefore, we assessed whether the effectiveness of statins in reducing the risk of MI was modified by the GNB3 C825T polymorphism. METHODS: In a population-based registry of pharmacy records linked to hospital discharge records (PHARMO), we used a nested case-control design. We selected patients hospitalized for MI as cases if they used antihypertensive drugs and had a diagnosis of hypercholesterolemia before their first MI. Controls met the same eligibility criteria, but were not hospitalized for MI. Logistic regression analysis was used to calculate odds ratios (OR) and synergy index with corresponding 95% confidence intervals (CI), and to adjust for potential confounding factors. RESULTS: We included 459 cases and 1805 controls. The risk of MI was significantly lower among participants exposed to statins compared with participants not exposed to statins (adjusted OR: 0.37, 95% CI: 0.29-0.47). The GNB3T allele was associated with a reduced risk of MI (adjusted OR: 0.74, 95% CI: 0.60-0.92). Among homozygous wild-type (CC) individuals (n=1119), exposure to statins was associated with a lower risk of MI (OR: 0.48, 95% CI: 0.34-0.67). However, T allele carriers (CT and TT) who used statins had an even stronger reduced risk of MI (OR: 0.27, 95% CI: 0.19-0.39). Overall, the interaction between exposure to statins and the GNB3 C825T polymorphism was significantly increased on the multiplicative scale (synergy index: 1.67, 95% CI: 1.06-2.65). CONCLUSION: Our findings show that T allele carriers of the GNB3 C825T polymorphism have less risk of MI and are more likely to benefit from statin therapy in a hypercholesterolemic population of antihypertensive drug users.     

Cancer incidence in a general population of asthma patients

PURPOSE: Several studies have assessed the association between asthma and cancer but none of them revealed a clear pattern of association. We aimed to examine the association between asthma, chronic obstructive pulmonary disease (COPD), and cancer. METHODS: We performed a cohort study with a nested case-control analysis using the General Practitioner Research Database in the UK. We defined three cohorts: patients with asthma, patients with COPD, and general population. During the follow-up, we identified a total of 5263 incident cases of cancer. We conducted a nested case-control analysis that included all cancer cases as well as 20 000 controls free of cancer frequency-matched on age, sex, and calendar year. RESULTS: Patients with asthma did not have an overall greater risk of cancer compared with the general population (odds ratio = 0.93, 95% confidence interval (CI): 0.86-1.00). However, they presented an elevated risk of experiencing lung cancer (odds ratio = 1.84, 95%CI: 1.58-2.15). Controlling for smoking and other potential confounding factors yielded a lower estimate (odds ratio = 1.35, 95%CI: 1.15-1.59). This estimate contrasted with that observed for non-smoking related cancer (0.87, 95%CI: 0.80-0.94). Overall, respiratory drugs did not seem to be associated with cancer among asthmatic patients. Patients with COPD had an Odds ratio of cancer of 1.26 (95%CI: 1.12-1.43) compared with the general population. CONCLUSIONS: Asthma was not associated with an increased risk of cancer. In fact, the risk of non-smoking related cancer was slightly reduced. However, we observed a small-elevated risk of lung cancer among asthmatic patients. Whether this result is a due to residual confounding and/or protopathic bias remains unclear. Further investigation is warranted to confirm or discard these associations.     

Health-related behavior and the use of hormone replacement therapy

PURPOSE: To study health-related differences between hormone replacement therapy (HRT) users and nonusers among colorectal cases and women without diagnosed cancer. METHODS: Data from the Saskatchewan Health population-based databases were used to ascertain the use of HRT, oral contraceptives (OCs), cardiovascular system (CVS) drugs, central nervous system (CNS) drugs, prescribed NSAIDs and vitamins among 3338 women diagnosed with colorectal cancer and 13025 women without diagnosed cancer. Physician visits and sigmoidoscopy procedures were also determined. RESULTS: Among women without diagnosed cancer, HRT was associated with CVS drugs (OR = 1.23, 95%CI: 1.10-1.37), CNS drugs (OR = 1.96, 95% CI: 1.72-2.23), other hormones (OR = 1.12, 95% CI: 1.01-1.24), prescribed vitamins (OR = 1.37, 95% CI: 1.22-1.55), NSAIDs (OR = 1.41, 95% CI: 1.18-1.68), having had a sigmoidoscopy 3-5 years prior to index dates (OR = 1.33, 95% CI: 1.12-1.59) and 15 or more visits to physicians during the 5th year prior to assigned index date (OR = 2.0, 95% CI: 1.77-2.35). Similar results were observed among women diagnosed with colorectal cancer, but HRT use was not associated with having had a sigmoidoscopy. CONCLUSIONS: Health-related characteristics of HRT users and nonusers are identified and described. Some of these factors may contribute to selection bias in studies examining the health benefits of HRT.     

Reserpine and breast cancer in women in Germany

Summary Exposure to reserpine was compared in 181 women interviewed prior to biopsy and found to have breast cancer and 307 women found to have a benign disorder of the breast. The age-adjusted relative risk of breast cancer in those who had taken reserpine was 0.6 (95% confidence limits: 0.4 and 1.1). When the 181 breast cancer patients were compared with a second control group of 101 women with a benign condition requiring surgery, the relative risk was 0.9 (95% confidence limits: 0.4 and 1.7). Neither long-term exposure nor its timing, gave any evidence of an association with breast cancer. The findings in this study do not support the hypothesis that rauwolfia derivatives initiate or promote breast cancer.This study was financially supported by the Ministery of Youth, Family and Health of the Fed. Rep. of Germany     

Achilles tendon rupture and its association with fluoroquinolone antibiotics and other potential risk factors in a managed care population

BACKGROUND: Case reports and observational studies have implicated fluoroquinolone antibiotic exposure as a risk factor for Achilles tendon rupture (ATR), an uncommon condition for which there are few formal studies. We sought to quantify the strength of association between exposure to fluoroquinolone antibiotics and the occurrence of ATR, accounting for other risk factors. METHODS: This was a case-control study nested within a health insurer cohort. Cases of ATR were identified and confirmed using patterns of health insurance claims that were validated through sampled medical record review. Information on risk factors, including fluoroquinolone exposure, came from health insurance claims. RESULTS: There were 947 cases of ATR and 18 940 controls. A dispensing of a fluoroquinolone antibiotic in the past 6 months was more common among ATR cases than controls, although not significantly so (odds ratio (OR) = 1.2; 95% confidence interval (CI) = 0.9-1.7), and exposure to a higher cumulative fluoroquinolone dose was more strongly associated (OR = 1.5, 95%CI = 1.0-2.3). Other risk factors for ATR were trauma (OR = 17.2, 95%CI = 14.0-20.2), male sex (OR = 3.0, 95%CI = 2.6-3.5), injected corticosteroid administration (OR = 2.2, 95%CI = 1.6-2.9), obesity (OR = 2.0, 95%CI = 1.2-3.1), rheumatoid arthritis (OR = 1.9, 95%CI = 1.0-3.7), skin or soft tissue infections (OR = 1.5, 95%CI = 0.9-2.3), oral corticosteroids (OR = 1.4, 95%CI = 1.0-1.8), and non-fluoroquinolone antibiotics (OR = 1.2, 95%CI = 1.1-1.5). CONCLUSIONS: The elevation in ATR risk associated with fluoroquinolones was similar in magnitude to that associated with oral corticosteroids or non-fluoroquinolone antibiotics. Trauma and male sex were more strongly associated with ATR, as were obesity and injected corticosteroids.     

Malformation rates in children of women with untreated epilepsy: a meta-analysis.

BACKGROUND: It is widely quoted that women with epilepsy have a higher than baseline risk for giving birth to a child with malformations, independent of the effects of antiepileptic drugs. OBJECTIVE: To determine, based on available evidence, if epilepsy per se represents a teratogenic risk. To systematically review all studies investigating the occurrence of major malformation rates among children of treated or untreated women with epilepsy and non-exposed controls who do not have epilepsy. METHODS: A meta-analysis, using a random effects model, was conducted of all cohort and case-control studies reporting malformation rates in children of women with epilepsy exposed or unexposed to antiepileptic drugs compared with that of children of nonepileptic women. Medline (1966-2001), EMBASE, the Cochrane database as well as REPROTOX (an information system on environmental hazards to human reproduction and development) databases were accessed. RESULTS: We found ten studies reporting results of untreated epilepsy (n = 400) and their non-epileptic healthy controls (n = 2492). Nine out of ten studies also reported results on 1443 patients exposed to antiepileptic drugs and their 2526 unexposed healthy controls. The risk for congenital malformations in the offspring of women with untreated epilepsy was not higher than among nonepileptic controls (odds ratio [OR] = 1.92; 95% CI 0.92-4.00). There was evidence of publication bias, thus with bias removed the OR was 0.99 (95% CI 0.49-2.01). In contrast, the offspring of epileptic women who received antiepileptic drugs had higher incidences of malformation than controls (OR 3.26; 95% CI 2.15-4.93). CONCLUSION: Our study does not support the commonly held view that epilepsy per se represents a teratogenic risk. Our study suggests that this view is the result of a publication bias, with several small (< 100 participants) positive studies leading to a premature conclusion.     

Antihypertensive drug therapy and the risk of lower extremity amputations in pharmacologically treated type 2 diabetes patients

PURPOSE: The objective of this study was to determine the association between different antihypertensive drug therapies and lower extremity amputations (LEAs) in type 2 diabetes patients. METHODS: Data were obtained from the PHARMO Record Linkage System comprising pharmacy records and data on hospitalisations for all 450,000 residents of eight Dutch cities. In a nested case-control study among 12,140 type 2 diabetes patients who used antihypertensive drugs, 26 cases with a first LEA and 94 controls without a LEA matched on age, sex and calendar time were identified. Logistic regression was used to estimate the relative risk of LEA and to adjust for potential confounding factors. RESULTS: Among type 2 diabetes patients who used antihypertensive drugs, subjects who used thiazide diuretics, alone or in combination, had a higher risk of LEA compared to subjects who used Angiotensin Converting Enzyme (ACE) inhibitor monotherapy (crude odds ratio (OR): 6.11 [95% confidence interval (CI): 1.32-28.27]). The use of thiazide diuretics was also associated with an increased risk of LEA when compared to the use of any non-thiazide antihypertensive drug (adjusted OR: 7.04 [1.10-45.30]). The increased risk of LEA associated with the use of thiazides compared to the use of non-thiazides depended on the duration of use (adjusted OR(< or = 365 days), 4.82 [0.61-38.34] and adjusted OR(>365 days), 26.16 [1.02-674.02], p-trend = 0.01). CONCLUSIONS: Treatment with thiazide diuretics compared to treatment with other antihypertensive drugs was associated with excess amputations in type 2 diabetes patients. Due to several limitations of this study, our findings do not preclude the use of thiazides in type 2 diabetes mellitus patients as yet.     

Risk of breast cancer in association with exposure to two different groups of tricyclic antidepressants

PURPOSE: In 2002, we reported an epidemiological study in which we found that some tricyclic antidepressants (identified as genotoxic in Drosophila Melanogaster) were associated with an increased risk of breast cancer, when exposure took place 11-15 years before the date of diagnosis. The implications of the results found lead us to carry out a separate case-control study, using the same source population, to validate the conclusions drawn from our previous study. METHODS: We accrued 7330 breast cancer cases, diagnosed between 1981 and 2000, and 29 320 controls matched on age and time. RESULTS: The association between exposure to genotoxic TCAs 11-15 years before diagnosis and the risk of breast cancer development was much weaker, as compared to what was reported in our previous study. The relative risk of breast cancer in women exposed to high doses of genotoxic TCAs 11-15 years before diagnosis was 1.17 (95%CI: 0.79-1.74), while in women exposed to high levels of non-genotoxic TCAs during the same period it was 0.95 (95%CI: 0.61-1.48). CONCLUSION: In conclusion, we did not find supporting evidence for an increased risk of breast cancer among women exposed to TCAs up to 20 years in the past.     

Antihypertensive treatment is associated with improved left ventricular geometry: the Rotterdam Study

PURPOSE: Left ventricular hypertrophy (LVH) increases the risk of cardiovascular disease. We evaluated the association between antihypertensive therapy and echocardiographically determined LVH. METHODS AND RESULTS: The Rotterdam Study is a population-based prospective cohort study among 7983 participants aged 55 years or over. Echocardiography was performed in 2823 participants. The study population consisted of 740 participants with grade 1 hypertension or antihypertensive monotherapy, without heart failure. Of these, 646 had an adequate echocardiogram for analysis of relative wall thickness (RWT) and 642 for left ventricular mass index. Participants were followed from 1 January 1991 until the date of echocardiography, between September 1992 and June 1993. Outcome measures were defined as being in the highest gender-specific quintile of left ventricular mass index and as having a RWT higher than 0.43. A Cox regression model with duration of use of antihypertensives defined as time-dependent covariates was used for data-analysis. Antihypertensive treatment lowered the risk of increased left ventricular mass index (RR 0.6, 95%CI 0.4-0.9). ACE-inhibitors, diuretics and beta-blockers all showed a risk reduction. Use of antihypertensives was also associated, although non-significantly, with a decrease of high RWT (RR 0.8, 95%CI 0.6-1.0). ACE-inhibitors, beta-blockers and calcium antagonists showed similar risk reductions, while diuretics seemed to increase the risk, possibly by reducing left ventricular end diastolic diameter. CONCLUSIONS: The use of antihypertensive drugs is associated with a decreased risk of echocardiographically determined LVH in a population-based setting.     

Combined COMT and GST genotypes and hormone replacement therapy associated breast cancer risk.

Our previous studies suggested that both COMT and GST genotypes might modify individual breast cancer risk. Here, we extended the studies to examine the potential combined effect of these genotypes in susceptibility to breast cancer. Our study population consisted of 483 Finnish breast cancer cases and 482 population control subjects. The odds ratios (ORs) and (95%) confidence intervals (CIs) were calculated by unconditional logistic regression adjusting for known or suspected confounding factors. No significant increase in the overall breast cancer risk was seen for any combinations of the studied genotypes. However, a substantially increased risk of breast cancer was seen for women who had used hormone replacement therapy (HRT) and simultaneously carried the COMT-L allele containing genotypes and either the GSTP1 Ile/Ile genotype (OR 4.10, 95% CI 1.24-13.6) or the GSTT1 null genotype (OR 4.19, 95% CI 1.30-13.5). These associations appeared to be mainly attributable to long-term users of HRT; the respective ORs were 7.00 (95% CI 1.21-40.6) and 8.36 (95% CI 1.44-49.0) among the users of HRT of more than 30 months. In addition, the combination of COMT-L allele containing genotypes with the GSTM1 null genotype posed a remarkably increased risk (OR 9.10, 95% CI 1.84-45.0) of breast cancer in this study group. These results suggest that the use of HRT could substantially increase the risk of breast cancer among women with specific combinations of the at-risk genotypes of COMT and GST genes.     

The erbB2/HER2/neu receptor polymorphism Ile655Val and breast cancer risk

The erbB2 (HER2/neu) gene is found amplified in tumours. A single nucleotide polymorphism at codon 655 (Ile655Val) has been studied in a number of case-control studies with respect to breast cancer risk, with conflicting results. The aim of the present study was to examine the association between this polymorphism and breast cancer risk in a prospective, predominantly Caucasian cohort of women, the Nurses' Health Study. We genotyped the Ile655Val single nucleotide polymorphism (rs1801200) in 1271 incident breast cancer cases, and 1667 controls who were selected from the Nurses' Health Study blood cohort. Controls were matched to cases on age, menopausal status, fasting status and postmenopausal hormone use at blood draw. An inverse association was observed between the Val/Val genotype and breast cancer risk (Val/Val versus Ile/Ile odds ratio=0.68, 95% confidence interval 0.47-0.98). We conclude that this polymorphism is not associated with an increase in breast cancer risk, and may in fact be associated with a modest decrease in risk.     

Gallbladder disease in the general population: association with cardiovascular morbidity and therapy

PURPOSE: Both gallbladder (GB) and cardiovascular disease are very common diagnoses that carry substantial economic costs. Prior studies suggest that personal history of ischaemic heart disease (IHD) could determine the occurrence of GB disease. Additionally the use of thiazide diuretics may also be a risk factor for this condition. We aimed to evaluate different cardiovascular conditions and related drugs that could be associated with GB disease. METHODS: We identified all incident cases of gallbladder disease occurring during 1996 among patients aged 20-79 years old registered in the General Practitioner Research Database. We performed a nested case control analysis using 2353 cases and 10,000 controls frequency matched to the cases by age and sex. RESULTS: After adjusting for potential confounders IHD was associated with a small increased risk of GB disease (1.29, 95%CI:1.08-1.55). When only cases requiring cholecystectomy were considered in the analysis, the resulting estimate was 1.06 (95%CI:0.83-1.35). Users of thiazide diuretics presented an OR of 1.36 (95%CI:1.08-1.71). Other antihypertensive drugs were not associated with GB disease. CONCLUSIONS: Our results confirm the small increased risk of GB disease associated with thiazide diuretics. On the other hand, our data do not support a major association between IHD and GB disease.