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Brian L Strom

Publications and source records attributed to Brian L Strom.

At least 37 records · Page 2Linked to original sources
PubMed2006

Relationship between established breast cancer risk factors and risk of seven different histologic types of invasive breast cancer.

BACKGROUND: Important differences in the contributions of certain exposures to the risks of ductal versus lobular breast carcinomas have been observed, but few studies have evaluated the relationships between established breast cancer risk factors and other histologic types. METHODS: Information on family history of cancer and reproductive, hormonal, anthropometric, and lifestyle characteristics were collected in a multicenter population-based case-control study consisting of 3,463 ductal, 274 lobular, 261 ductal-lobular, 91 medullary, 77 tubular, 70 comedo, and 61 mucinous invasive breast carcinoma cases (ages 35-64 years, newly diagnosed 1994-1998) and 4,682 controls. Associations between each of these histologic types and various exposures were evaluated using polytomous regression. RESULTS: Heterogeneity in the risks of different histologic types of breast cancer was observed for three exposures: menopausal hormone use, body mass index (BMI), and alcohol consumption. Specifically, current use of unopposed estrogen was associated with a reduced risk of ductal carcinoma and increased risk of comedocarcinoma, and current use of estrogen and progestin was associated with elevated risks of ductal-lobular and tubular carcinomas. Among postmenopausal women, BMI was only inversely related to risk of ductal-lobular carcinoma, and alcohol use was only positively related to risk of lobular carcinoma. CONCLUSIONS: Variations in the associations between known breast cancer risk factors and risk of different breast cancer histologies were observed. Although these findings require confirmation, and the analyses of some histologic groups were limited by small sample sizes, they provide some insight into the different etiologies of various histologic subtypes of breast cancer.

Adenocarcinoma, Mucinous↗
PubMed2006

Reacting to antibiotic allergies.

About 10-15% of all adults report that they are allergic penicillin or other antibiotics, although the accuracy and significance these reports remain unclear. In the outpatient setting, clinicians face a dilemma in prescribing for patients with a history of an allergic reaction to antibiotics. Which drugs should these patients avoid? Are these patients at increased risk for an allergic reaction to related drugs? This Issue Brief summarizes several large studies that can help guide improve the management of patients with antibiotic allergies.

Anti-Bacterial Agents↗
PubMed2005

Lifetime recreational exercise activity and breast cancer risk among black women and white women.

BACKGROUND: Physical inactivity is a potentially modifiable breast cancer risk factor. Because few data on this relationship exist for black women, we examined the relationship between breast cancer risk and lifetime and time- or age-specific measures of recreational exercise activity among white women and among black women. METHODS: The Women's Contraceptive and Reproductive Experiences Study was a multicenter population-based case-control study of black women and white women aged 35-64 years with newly diagnosed invasive breast cancer. We collected detailed histories of lifetime recreational exercise activity during in-person interviews with 4538 case patients with breast cancer (1605 black and 2933 white) and 4649 control subjects (1646 black and 3033 white). Control subjects were frequency-matched to case patients on age, race, and study site. We examined associations between exercise activity measures (metabolic equivalents of energy expenditure [MET]-hours per week per year) and breast cancer risk overall and among subgroups defined by race, other breast cancer risk factors, and tumor characteristics by use of unconditional logistic regression. All statistical tests were two-sided. RESULTS: Among all women, decreased breast cancer risk was associated with increased levels of lifetime exercise activity (e.g., average MET-hours per week per year, P(trend) = .002). An average annual lifetime exercise activity that was greater than the median level for active control subjects was associated with an approximately 20% lower risk of breast cancer, compared with that for inactivity (for 6.7-15.1 MET-hours/week/year, odds ratio [OR] = 0.82, 95% confidence interval [CI] = 0.71 to 0.93; for > or =15.2 MET-hours/week/year, OR = 0.80, 95% CI = 0.70 to 0.92). The inverse associations did not differ between black and white women (for MET-hours/week/year, P(trend) = .003 and P(trend) = .09, respectively; homogeneity of trends P = .16). No modification of risk was observed by disease stage, estrogen receptor status, or any breast cancer risk factor other than first-degree family history of breast cancer. CONCLUSIONS: This study supports an inverse association between physical activity and breast cancer among black women and among white women.

Adolescent↗
PubMed2005

Effect of GB virus C viremia on HIV acquisition and HIV set-point.

We performed both a case-control study and a cohort study to determine whether GB virus C (GBV-C) viremia prevents the acquisition of HIV infection or alters the HIV set-point after infection. The prevalence of GBV-C viremia in HIV-uninfected individuals who did and did not acquire HIV were similar (odds ratio 1.32; 95% confidence interval 0.6-2.6). Pre-existing GBV-C viremia at the time of HIV acquisition was also not associated with lower plasma HIV-RNA levels.

Adult↗
PubMed2005

Use of selective serotonin reuptake inhibitors and the risk of breast cancer.

Selective serotonin reuptake inhibitors (SSRIs) were introduced in 1987 and, by 1997, were prescribed to 58% of Americans receiving outpatient treatment for depression. In 1992, a study reported that one of the SSRIs, fluoxetine, accelerated the growth of mammary tumors in rodents. By use of data from 1988 to 2002 from their hospital-based, case-control surveillance study, the authors examined the relation between use of SSRIs and risk of breast cancer. Nurse interviewers administered standard questionnaires to patients admitted to hospitals in three US centers to obtain information on demographic, medical, and lifestyle factors and to elicit a history of drug use, including antidepressants. Cases comprised 2,138 women with primary invasive breast cancer, and controls comprised 2,858 women admitted with nonmalignant diagnoses unrelated to SSRI use. The authors used multivariate conditional logistic regression models to estimate odds ratios for breast cancer among regular users of SSRIs compared with nonusers. The odds ratio was 1.1 (95% confidence interval: 0.8, 1.7) for regular use of SSRIs and 0.7 (95% confidence interval: 0.4, 1.5) for use of 4 or more years. Odds ratios were not elevated for any specific SSRI. These data provide some assurance that the use of SSRIs does not increase the risk of breast cancer.

Adult↗
PubMed2005

Use of nonsteroidal antiinflammatory drugs and risk of breast cancer: the Case-Control Surveillance Study revisited.

Several studies have suggested that use of nonsteroidal antiinflammatory drugs (NSAIDs) may reduce the risk of breast cancer. Reductions in risk may vary according to the hormone receptor status of the tumor or the type of NSAID used. The authors extended a previous US hospital-based case-control study (the Case-Control Surveillance Study) to include 444 additional cases, for a total of 7,006 incident breast cancer cases (1976-2002). They examined the relation between regular NSAID use and breast cancer risk using logistic regression to adjust for confounding. The odds ratio for regular use of NSAIDs was 0.78 (95% confidence interval: 0.63, 0.97), and a trend of decreasing risk with increasing duration of use was statistically significant (p for trend = 0.02). The inverse association with regular use of NSAIDs was stronger among premenopausal women (odds ratio = 0.62). The overall odds ratios for regular use of aspirin and ibuprofen were 0.86 and 0.85, respectively. The effect of NSAID use on breast cancer risk did not vary according to the hormone receptor status of the tumor. In conclusion, long-term regular use of NSAIDs was associated with decreased risk of breast cancer. The type of NSAID used or the hormone receptor status of the tumor did not modify the effect.

Adult↗
PubMed2005

Weight gain in the first week of life and overweight in adulthood: a cohort study of European American subjects fed infant formula.

BACKGROUND: Successful prevention of obesity and related cardiovascular risk factors requires a clear understanding of its determinants over the life course. Rapid infancy weight gain is associated with childhood obesity, whereas low infancy weight is associated with coronary heart disease. Our aim was to identify during which periods in infancy weight gain is associated with adult obesity. METHODS AND RESULTS: A cohort of European American formula-fed subjects, measured on 7 occasions during infancy as part of several infant formula studies, were contacted at age 20 to 32 years, when they reported usual adult weight and height. A life-course plot was used to identify critical periods of weight gain associated with adulthood overweight (body mass index > or =25 kg/m2). These associations were tested with logistic regressions. Data were available for 653 subjects (72% of eligible subjects). Approximately 32% of them were overweight adults. The period between birth and age 8 days was identified as potentially critical. After adjustment for important confounding factors, weight gain during the first week of life was associated with adulthood overweight status (OR for each 100-g increase 1.28, 95% CI 1.08 to 1.52), as was weight gain during the first 112 days of life (OR 1.04, 95% CI 1.01 to 1.08). Similar results were obtained after standardization with z scores from a reference population. CONCLUSIONS: In formula-fed infants, weight gain during the first week of life may be a critical determinant for the development of obesity several decades later. These results contribute to the understanding of chronic disease programming and suggest new approaches to obesity prevention.

Adult↗
PubMed2005

Race and electronically measured adherence to immunosuppressive medications after deceased donor renal transplantation.

Nonadherence to immunosuppressive medications may partly explain the worse allograft outcomes among black recipients of renal transplants. In a prospective cohort study of recipients of deceased donor renal transplants, microelectronic cap monitors were placed on bottles of one immunosuppressive medication to (1) measure average daily percentage adherence during the first posttransplantation year and (2) determine the factors associated with adherence. A total of 278 transplant recipients who provided sufficient microelectronic adherence data were grouped into four categories of average daily percentage adherence: 95 to 100% adherence (41.0% of patients), 80 to 95% adherence (32.4%), 50 to 80% adherence (12.9%), and 0 to 50% adherence (13.7%). In the unadjusted ordinal logistic regression model, black race was associated with decreased adherence (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.26 to 0.72; P = 0.001). Cause of renal disease, Powerful Others health locus of control, transplant center, and dosing frequency were also associated with adherence. After adjustment for transplant center and dosing frequency, the association between black race and decreased adherence was substantially attenuated (OR, 0.65; 95% CI, 0.38 to 1.14, P = 0.13). Transplant center (P = 0.003) and increased dosing frequency (OR, 0.43; 95% CI, 0.22 to 0.86, for three or four times per day dosing; OR, 2.35; 95% CI, 1.01 to 5.45, for daily dosing; versus two times per day dosing; P = 0.003) remained independently associated with adherence. Other baseline demographic, socioeconomic, medical, surgical, and psychosocial characteristics were not associated with adherence. The transplant center and dosing frequencies of immunosuppressive medications are associated with adherence and explain a substantial proportion of the race-adherence relationship.

Adult↗
PubMed2005

Role of computerized physician order entry systems in facilitating medication errors.

CONTEXT: Hospital computerized physician order entry (CPOE) systems are widely regarded as the technical solution to medication ordering errors, the largest identified source of preventable hospital medical error. Published studies report that CPOE reduces medication errors up to 81%. Few researchers, however, have focused on the existence or types of medication errors facilitated by CPOE. OBJECTIVE: To identify and quantify the role of CPOE in facilitating prescription error risks. DESIGN, SETTING, AND PARTICIPANTS: We performed a qualitative and quantitative study of house staff interaction with a CPOE system at a tertiary-care teaching hospital (2002-2004). We surveyed house staff (N = 261; 88% of CPOE users); conducted 5 focus groups and 32 intensive one-on-one interviews with house staff, information technology leaders, pharmacy leaders, attending physicians, and nurses; shadowed house staff and nurses; and observed them using CPOE. Participants included house staff, nurses, and hospital leaders. MAIN OUTCOME MEASURE: Examples of medication errors caused or exacerbated by the CPOE system. RESULTS: We found that a widely used CPOE system facilitated 22 types of medication error risks. Examples include fragmented CPOE displays that prevent a coherent view of patients' medications, pharmacy inventory displays mistaken for dosage guidelines, ignored antibiotic renewal notices placed on paper charts rather than in the CPOE system, separation of functions that facilitate double dosing and incompatible orders, and inflexible ordering formats generating wrong orders. Three quarters of the house staff reported observing each of these error risks, indicating that they occur weekly or more often. Use of multiple qualitative and survey methods identified and quantified error risks not previously considered, offering many opportunities for error reduction. CONCLUSIONS: In this study, we found that a leading CPOE system often facilitated medication error risks, with many reported to occur frequently. As CPOE systems are implemented, clinicians and hospitals must attend to errors that these systems cause in addition to errors that they prevent.

Clinical Pharmacy Information Systems↗
PubMed2005

Patients exposed to rofecoxib and celecoxib have different odds of nonfatal myocardial infarction.

BACKGROUND: Studies have postulated that cyclooxygenase-2 (COX-2) selective inhibitors affect cardiovascular risk through various mechanisms. Some of these mechanisms could increase risk (for example, inhibition of prostacyclin production), and some could decrease risk (for example, inhibition of inflammation). OBJECTIVE: To determine the effect of COX-2 inhibitors on risk for nonfatal myocardial infarction (MI). DESIGN: Case-control study. SETTING: 36 hospitals in a 5-county area. PARTICIPANTS: 1718 case-patients with a first, nonfatal MI admitted to these hospitals and 6800 controls randomly selected from the same counties. MEASUREMENTS: Self-reported medication use assessed through telephone interviews. RESULTS: The adjusted odds ratio for MI among celecoxib users, relative to persons who did not use nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs), was 0.43 (95% CI, 0.23 to 0.79) compared with 1.16 (CI, 0.70 to 1.93) among rofecoxib users. The use of rofecoxib was associated with a statistically significant higher odds of MI compared with the use of celecoxib (adjusted odds ratio for rofecoxib vs. celecoxib, 2.72 [CI, 1.24 to 5.95]; P = 0.01). Nonselective NSAIDs were associated with a reduced odds of nonfatal MI relative to nonusers. Comparisons of COX-2 inhibitors with nonselective NSAIDs were the following: rofecoxib versus naproxen (odds ratio, 3.39 [CI, 1.37 to 8.40]) and celecoxib versus ibuprofen or diclofenac (odds ratio, 0.77 [CI, 0.40 to 1.48]). LIMITATIONS: The possibility of recall bias and uncontrolled confounding in this observational study limit the ability to make definitive conclusions. The association of celecoxib with a lower odds of MI could have occurred by chance. Only about 50% of eligible participants completed telephone interviews. CONCLUSION: Celecoxib and rofecoxib were associated with different odds of MI. Cardiovascular effects among the COX-2 inhibitors seem different, but further studies, preferably randomized trials, are needed to fully understand the spectrum of effects of COX-2 inhibitors and potential differences among them.

Aged↗
PubMed2005

Epidemiologic studies of adverse effects of anti-retroviral drugs: how well is statistical power reported.

PURPOSE: To determine whether there is a difference in average statistical power between pharmacoepidemiologic studies of anti-retroviral adverse drug effects (ADEs) sponsored by for-profit versus non-profit organizations. METHODS: We studied all published pharmacoepidemiologic studies of ADEs associated with the 15 anti-retroviral drugs approved through the end of 1999. A priori, the primary outcome was the power of each study to detect a clinically important difference in the risk for an adverse effect among patients exposed to the study drug(s). We could not evaluate this outcome because of the infrequent reporting of power calculations. We instead report the distribution of studies across a 5-tiered measure of adequacy of reporting of statistical power, as well as the sponsorship of these studies. RESULTS: Of 48 studies meeting our inclusion criteria, only 1 (2%) reported either a completed, a priori power calculation or sufficient details for readers to calculate the power to detect a pre-defined, clinically important effect. Thirty-five studies (73%) reported the minimum information required for sophisticated readers to determine the power to detect an event rate of interest to them; 6 additional studies (13%) reported confidence intervals around at least one summary effect measure and 6 (13%) provided no indication of power or uncertainty. Of the 41 studies for which sponsorship was determined, only 3 (7%) were sponsored by for-profit organizations. CONCLUSIONS: The poor reporting of statistical power in this sample suggests a need for guidelines to improve the reporting of pharmacoepidemiologic studies of ADEs. Future research is needed to determine whether the observed paucity of industry-sponsored observational studies of anti-retroviral ADEs extends to other clinical areas, and if so, to identify the causes of this phenomenon.

Adverse Drug Reaction Reporting Systems↗
PubMed2005

The relationship between time since registration and measured incidence rates in the General Practice Research Database.

BACKGROUND: The General Practice Research Database (GPRD) is widely used to study incidence rates. This study examines whether incidence rates are overestimated during the first year after registration, how long one needs to wait to obtain accurate incidence rates, and whether the time period of overestimation differs among disease types. METHODS: We measured incidence rates of nine acute, eight chronic, and eight neoplastic outcomes in 3-month intervals through month 36 after enrollment in GPRD. The incidence rates in months 13-36 were used to estimate baseline incidence rates for each diagnosis. RESULTS: For patients registering with practices that were already UTS, incidence rates were highest in the first 3 months after registration. In eight of nine acute diagnoses, the incidence rate was within 20% of baseline by months 4-6; and in seven of eight cancers, the incidence rate was within 20% of baseline by months 7-9. For chronic conditions, the incidence rate in months 10-12 differed from baseline by more than 20% for five of the eight outcomes, respectively. For patients registering prior to UTS, incidence rates during the first quarter were within 20% of baseline for all acute and cancer diagnoses and six of eight chronic diagnoses. CONCLUSIONS: Reported incidence rates are highest in the first 3 months after registration with an UTS practice and decline to baseline over the first year, more quickly for acute conditions than chronic conditions. For patients who registered prior to UTS, incidence rates are near the baseline level at the start of follow-up.

Cohort Studies↗
PubMed2005

Practical aspects of sharing controls between case-control studies.

PURPOSE: We discuss the practical advantages and challenges of sharing controls among two or more concurrently conducted case-control studies. METHODS: We conducted two case-control studies, one of breast cancer and the other of endometrial cancer, with overlapping, shared control groups. The studies had overlapping geographic areas, identical telephone questionnaires and biosample collection, and identical age and race eligibility. RESULTS: Sharing controls reduced the number of potential controls that had to be identified by random-digit dialing by 25% and the number of eligible controls that had to be interviewed by 32%. The cost savings were approximately 2,96,000 dollars, or 7% of the program project that funded the studies. CONCLUSIONS: The disadvantage of sharing controls was the complexity of the design and the additional investigator time required to plan, monitor, and adjust the design. In the situation presented here, the complexities would have been reduced greatly if we had not attempted to frequency match on age in both studies. Generally, sharing controls is likely to work well when strict frequency matching is not required and there is a large overlap of interview questions, other data to be collected, and eligibility criteria among the studies.

Aged↗
PubMed2005

Racial differences in the familial aggregation of breast cancer and other female cancers.

Although breast cancer familial aggregation has been studied in Caucasians, information for African-Americans is scant. We used family cancer history from the Women's Contraceptive and Reproductive Experiences study to assess the aggregation of breast and gynecological cancers in African-American and Caucasian families. Information was available on 41,825 first and second-degree relatives of Caucasian and 28,956 relatives of African-American participants. We used a cohort approach in which the relative's cancer status was the outcome in unconditional logistic regression and adjusted for correlated data using generalized estimating equations. Race-specific models included a family history indicator, the relative's age, and type. Relative risk (RR) estimates for breast cancer were highest for first-degree relatives, and the overall RR for breast cancer among case relatives was 1.96 (95% CI = 1.68-2.30) for Caucasian and 1.78 (95% CI = 1.41-2.25) for African-Americans. The effect of CARE participants' reference age on their relatives' breast cancer risk was greatest among first-degree relatives of African-American patients with RRs (95% CI) for ages <45 and > or =45 of 2.97 (1.86-4.74) and 1.48 (1.14-1.92), respectively. Among Caucasians, first-degree relatives of case subjects were at greater risk for ovarian cancer, particularly relatives younger than 45 years (RR (95% CI) = 2.06 (1.02-4.12)), whereas African-American first-degree relatives of case subjects were at increased cervical cancer risk (RR (95% CI) = 2.17 (1.22-3.85). In conclusion, these racially distinct aggregation patterns may reflect different modes of inheritance and/or environmental factors that impact cancer risk.

Adult↗
PubMed2005

Risk of serious upper gastrointestinal toxicity with over-the-counter nonaspirin nonsteroidal anti-inflammatory drugs.

BACKGROUND & AIMS: Use of prescription nonaspirin nonsteroidal anti-inflammatory drugs (NANSAIDs) increases the risk of serious upper gastrointestinal toxicity. Less is known about over-the-counter (OTC) NANSAIDs, which are typically used at lower doses and for shorter durations. This study assessed the risk of toxicity with OTC NANSAIDs. METHODS: A total of 359 case subjects hospitalized for upper gastrointestinal bleeding, perforation, or benign gastric outlet obstruction were recruited from 28 hospitals. A total of 1889 control subjects were recruited by random digit dialing from the same region. Data on medication use were collected via structured telephone interview. RESULTS: Use of OTC NANSAIDs on > or = 4 days during the most recent week had an adjusted odds ratio (OR) of 1.83 (95% confidence interval [CI], 1.14-2.95). Use of high-dose OTC NANSAIDs during the index week had an adjusted OR of 5.21 (95% CI, 2.32-11.69). In contrast, use of OTC NANSAIDs <4 times during the index week (adjusted OR, 0.67; 95% CI, 0.43-1.06) and use of very low doses of prescription or OTC NANSAIDs during the index week (adjusted OR, 0.74; 95% CI, 0.49-1.12) were not significantly associated with an increased risk of serious gastrointestinal toxicity. We did not observe a significant difference between the risk of toxicity with OTC naproxen versus OTC ibuprofen (adjusted OR, 0.84; 95% CI, 0.26-2.70). CONCLUSIONS: Use of OTC NANSAIDs at recommended doses has a relatively good safety profile compared with prescription NANSAIDs. However, use of high-dose OTC NANSAIDs (comparable to a prescription dose) is associated with serious gastrointestinal toxicity.

Adult↗
PubMed2005

Association of catechol-O-methyltransferase with smoking cessation in two independent studies of women.

OBJECTIVES AND METHODS: The Val108/158Met polymorphism in the gene that encodes COMT, a dopamine metabolizing enzyme, results in a three- to four-fold reduction in COMT activity. To determine if the lower activity Met allele of COMT was associated with smoking cessation in women, we used two independent studies: a population-based case--control study and a nicotine replacement clinical trial. RESULTS: In the case--control study, women with two Met alleles were significantly more likely to be ex-smokers than current smokers [OR=1.82, 95% CI (1.05, 3.17), P=0.03]. In the nicotine replacement clinical trial, among women, the Met/Met genotype was associated with a higher probability of smoking cessation based on both point prevalence and prolonged abstinence outcomes [OR=2.96, 95% CI (1.07, 8.14), P=0.04; OR=3.23, 95% CI (1.13, 9.20), P=0.03, respectively]. CONCLUSIONS: This first report of a significant association between COMT Val108/158Met and smoking cessation suggests that COMT variation has an effect on smoking behavior in women.

Aged↗