***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The risk of cancer in users of verapamil  was assessed in a long-term follow-up of 1,775 patients who were r and omized to verapamil or matching placebo in the Danish Verapamil Infa rct ion Trial-II in the years 1985 to 1987 . During 10,474 patient-years , no increased risk of cancer was observed for the verapamil-treated men or women compared with the age- and sex-matched background population Background — The obesity-hypertension link over the life course has not been well characterized , although the prevalence of obesity and hypertension is increasing in the United States . Methods and Results — We studied the association of body mass index ( BMI ) in young adulthood , into middle age , and through late life with risk of developing hypertension  in 1132 white men of The Johns Hopkins Precursors Study , a prospect i ve cohort study . Over a median follow-up period of 46 years , 508 men developed hypertension . Obesity ( BMI ≥30 kg/m2 ) in young adulthood was strongly associated with incident hypertension ( hazard ratio , 4.17 ; 95 % confidence interval , 2.34–7.42 ) . Overweight ( BMI 25 to < 30 kg/m2 ) also signaled increased risk ( hazard ratio , 1.58 ; 95 % confidence interval , 1.28–1.96 ) . Men of normal weight at age 25 years who became overweight or obese at age 45 years were at increased risk compared with men of normal weight at both times ( hazard ratio , 1.57 ; 95 % confidence interval , 1.20–2.07 ) , but not men who were overweight or obese at age 25 years who returned to normal weight at age 45 years ( hazard ratio , 0.91 ; 95 % confidence interval , 0.43–1.92 ) . After adjustment for time-dependent number of cigarettes smoked , cups of coffee taken , alcohol intake , physical activity , parental premature hypertension , and baseline BMI , the rate of change in BMI over the life course increased the risk of incident hypertension in a dose-response fashion , with the highest risk among men with the greatest increase in BMI ( hazard ratio , 2.52 ; 95 % confidence interval , 1.82–3.49 ) . Conclusions — Our findings underscore the importance of higher weight and weight gain in increasing the risk of hypertension from young adulthood through middle age and into late life Background We investigated the association between hypertension , antihypertensive ( AH ) medication use , and breast cancer  in a large prospect i ve study , the California Teachers Study ( CTS ) . Methods Information on history of hypertension and lifetime regular use of AH medications was collected from 114,549 women in 1995–1996 . Among them , 4,151 invasive breast cancers were diagnosed between 1995 and 2006 . Additional information on AH  use was collected from 73,742 women in 2000–2001 , and 1,714 of these women were subsequently diagnosed with breast cancer . Cox proportional hazards regression was used to estimate relative risks ( RR ) and 95 % confidence intervals ( CI ) for breast cancer . Results Use of AH medication for ≥5 years , when compared with no use , was associated with a modest increased risk of invasive breast cancer ( RR = 1.18 , 95%CI 1.02–1.36 ) . This increased risk appeared to be confined to estrogen receptor (ER)-positive tumors ( RR = 1.21 , 95%CI 1.03–1.43 ) and pre-/peri-menopausal women ( RR = 1.58 , 95%CI 1.11–2.25 ) . Conclusions Increased risk of invasive breast cancer was observed for long-term ( ≥5 years ) AH use , and this appeared to be confined to ER + breast cancer and younger women The association between angiotensin receptor blockers ( ARBs ) and cancer is controversial with meta-analyses of r and omized controlled trials and observational studies reporting conflicting results . Thus , the objective of this study was to determine whether ARBs are associated with an overall increased risk of the four most common cancers , namely , lung , colorectal , breast and prostate cancers , and to explore these effects separately for each cancer type . We conducted a retrospective cohort study using a nested case-control analysis within the United Kingdom ( UK ) General Practice Research Data base . We assembled a cohort of patients prescribed antihypertensive agents between 1995 , the year the first ARB ( losartan ) entered the UK market , and 2008 , with follow-up until December 31 , 2010 . Cases were patients newly-diagnosed with lung , colorectal , breast and prostate cancer during follow-up . We used conditional logistic regression to estimate adjusted rate ratios ( RRs ) and 95 % confidence intervals ( CIs ) of cancer incidence , comparing ever use of ARBs with ever use of diuretics and /or beta-blockers .  The cohort included 1,165,781 patients , during which 41,059 patients were diagnosed with one of the cancers under study ( rate 554/100,000 person-years ) . When compared to diuretics and /or beta-blockers , ever use of ARBs was not associated with an increased rate of cancer overall ( RR : 1.00 ; 95 % CI : 0.96–1.03 ) or with each cancer site separately . The use of angiotensin-converting enzyme inhibitors and calcium channel blockers was associated with an increased rate of lung cancer ( RR : 1.13 ; 95 % CI : 1.06–1.20 and RR : 1.19 ; 95 % CI : 1.12–1.27 , respectively ) . This study provides additional evidence that the use of ARBs does not increase the risk of cancer overall or any of the four major cancer sites . Additional research is needed to further investigate a potentially increased risk of lung cancer with angiotensin-converting enzyme inhibitors and calcium channel blockers Background In a recent case – control study , long-term use of calcium channel blocking drugs was associated with a greater-than-twofold increased breast cancer risk . If prospect ively collected data confirm that calcium channel blocker use increases breast cancer risk , this would have major implication s for hypertension treatment . The objective of this study was to determine whether women using calcium channel blockers for 10 years or more were at increased risk of developing breast cancer compared with women not using calcium channel blockers . Methods The Sister Study is a prospect i ve volunteer cohort study of women from the USA and Puerto Rico design ed to evaluate environmental and genetic risk factors for breast cancer . Beginning in 2003 , women between the ages of 35 and 74 were recruited . They were eligible to participate if they had a sister with breast cancer but had not been diagnosed with breast cancer themselves . In total , 50,884 women enrolled in the cohort between 2003 and 2009 ; 50,757 women with relevant baseline data and available follow-up data are included in this study . The exposure of interest is current use of calcium channel blocking drugs and the reported duration of use at entry into the cohort . Secondary exposures of interest were the duration and frequency of use for all other subclasses of antihypertensive drugs . Our main outcome is a self-reported diagnosis of breast cancer during the study follow-up period . With patient permission , self-reported diagnoses were confirmed using medical records . Results Results showed 15,817 participants were currently using an antihypertensive drug , and 3316 women were currently using a calcium channel blocker  at study baseline ; 1965 women reported a breast cancer diagnosis during study follow-up . Using Cox proportional hazards modeling , we found no increased risk of breast cancer among women who had been using calcium channel blockers for 10 years or more compared with never users of calcium channel blockers ( HR 0.88 , 95 % CI 0.58–1.33 ) . Conclusions We saw no evidence of increased risk of breast cancer from 10 years or more of current calcium channel blocker use . Our results do not support avoiding calcium channel blocking drugs in order to reduce breast cancer risk Purpose Use of specific antihypertensive medications ( AHTs ) has been hypothesized to increase breast cancer risk , but results across published studies are inconsistent . Methods We re-evaluated the relationship between AHT use and  breast cancer risk  in a prospect i ve cohort of 3,201 women ≥65 years of age at recruitment now with more than double the length of follow-up ( 12 vs. 5 years ) and substantially more breast cancer diagnoses ( 188 compared with 75 cases ) . We estimated the association between AHT use overall as well as use of specific formulations ( based on data collected annually ) and breast cancer risk using multivariate-adjusted Cox regression . Results Compared with women who reported no use of AHTs , women who had used calcium channel blockers ( CCB ) within the past two years had a 1.6-fold increased risk of breast cancer ( 95 % confidence interval ( CI ) : 1.0–2.5 ) , and in particular , recent users of immediate-release CCBs had a 2.4-fold increased risk ( 95 % CI : 1.3–4.5 ) . Neither ever nor recent use of any other type of AHT was associated with breast cancer risk . Conclusions While the observed association between immediate-release CCBs and breast cancer risk is based on a small sample size and needs to be interpreted cautiously , this result is consistent with others in the literature . However , given declines in use of these preparations in favor of sustained-release CCBs , which was not related to risk , the potential clinical and public health impact of this association is limited . This study also adds to the evidence that other commonly used AHTs are not strongly related to breast cancer risk BACKGROUND AND OBJECTIVE In many observational studies , the association between drugs and disease is analyzed with information from a baseline interview . We investigated the magnitude and direction of exposure misclassification by comparing interview data at baseline with prospect ively gathered pharmacy data . METHODS The study population for this study consisted of a cohort of 2,487 participants aged 71 years or older from the Rotterdam Study . Data on drug use were gathered at the baseline interview and through pharmacies during the follow-up period between January 1 , 1991 , and January 1 , 1999 . We assessed the sensitivity , specificity , and positive and negative predictive value of  interview data  as proxy measures of chronic use of calcium channel blockers ( CCB ) in comparison with longitudinal medication records from the pharmacy . RESULTS Only 3 of the 206 subjects ( 1.5 % ) who reported use at baseline did not use CCBs during follow-up . Of the 2,281 persons who reported no use of CCBs at baseline , however , 354 actually used CCBs during follow-up ( 15.5 % ) . The difference between interview data and pharmacy records corresponded to a misclassification bias of 0.73 ( 95%CI : 0.52 - 1.02 ) . CONCLUSION Misclassification of exposure was high when interview data were used as a proxy measure of chronic use during follow-up Summary Aim : We describe the safety profile of nifedipine GITS as assessed from adverse events reported in the ACTION trial in which 7,665 patients with stable , symptomatic coronary artery disease were r and omly assigned nifedipine GITS or placebo and followed for a mean of 4.9 years . Methods : All adverse events were coded using the COSTART coding dictionary . The incidence rate for each event was calculated as the number of patients with the event concerned divided by the total time ‘ at risk ’ . Hazard ratios comparing nifedipine with placebo and their 95 % confidence intervals were obtained by Cox proportional-hazards analysis . Results : As reported previously , nifedipine significantly reduced the incidence of cardiovascular events and procedures [ hazard ratio ( HR ) 0.89 , 95 % confidence interval ( CI ) 0.83–0.95 ] . Apart from the known side effects of nifedipine , which include peripheral oedema , vasodilatation , hypotension , asthenia , constipation , leg cramps , non-specific respiratory complaints , impotence and polyuria , and which were reported more frequently in patients assigned nifedipine , the incidence rates of most other adverse events were similar . There were no differences in the occurrence of gastrointestinal haemorrhage , myocardial infa rct ion and suicide . The rate of occurrence of death or new cancer excluding non-melanoma skin cancer for patients with no history of cancer at baseline was 2.53/100 patient years for patients assigned nifedipine and 2.37/100 patient years for patients assigned placebo ( HR 1.06 , 95 % CI 0.93–1.22 ) . Conclusion : Overall nifedipine GITS was well tolerated by patients with stable symptomatic angina Recent reports suggest a possible link between nifedipine ( but not diltiazem ) and an increased risk of cancer in patients being treated with calcium antagonists Some studies have suggested that the use of calcium channel blockers may increase the risk of cancer . A possible association of the use of calcium channel blockers with cancer incidence and cancer mortality was addressed using data from the Nurses ' Health Study BACKGROUND Calcium-channel blockers can alter apoptosis , a mechanism for destruction of cancer cells . We examined whether the long-term use of calcium-channel blockers is associated with an increased risk of cancer . METHODS Between 1988 and 1992 we carried out a prospect i ve cohort study of 5052 people aged 71 
    Output:
    
The current summative evidence does not support a clear association between taking CCBs and developing breast cancer .
However , uncertainty remains , especially for long-term use and any association might not be uniform between different population s and /or breast cancer sub-types .