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Biomedical subjects

Brian L Strom

Publications and source records attributed to Brian L Strom.

At least 73 records · Page 4Linked to original sources

Absence of cross-reactivity between sulfonamide antibiotics and sulfonamide nonantibiotics.

BACKGROUND: The safety of sulfonamide nonantibiotics is unclear in patients with prior allergic reactions to sulfonamide antibiotics. METHODS: We conducted a retrospective cohort study using the General Practice Research Database in the United Kingdom, examining the risk of allergic reactions within 30 days after the receipt of a sulfonamide nonantibiotic. Patients with evidence of prior hypersensitivity after the receipt of a sulfonamide antibiotic were compared with those without such evidence. Similar analyses were also performed with the use of penicillins instead of sulfonamides, to determine whether any risk was specific to sulfonamide cross-reactivity. RESULTS: Of 969 patients with an allergic reaction after a sulfonamide antibiotic, 96 (9.9 percent) had an allergic reaction after subsequently receiving a sulfonamide nonantibiotic. Of 19,257 who had no allergic reaction after a sulfonamide antibiotic, 315 (1.6 percent) had an allergic reaction after receiving a sulfonamide nonantibiotic (adjusted odds ratio, 2.8; 95 percent confidence interval, 2.1 to 3.7). However, the risk of allergic reactions was even greater after the receipt of a penicillin among patients with a prior hypersensitivity reaction to a sulfonamide antibiotic, as compared with patients with no such history (adjusted odds ratio, 3.9; 95 percent confidence interval, 3.5 to 4.3). Furthermore, among those with a prior hypersensitivity reaction after the receipt of a sulfonamide antibiotic, the risk of an allergic reaction after the subsequent receipt of a sulfonamide nonantibiotic was lower than the risk of an allergic reaction after the subsequent receipt of a penicillin (adjusted odds ratio, 0.7; 95 percent confidence interval, 0.5 to 0.9). Finally, the risk of an allergic reaction after the receipt of a sulfonamide nonantibiotic was lower among patients with a history of hypersensitivity to sulfonamide antibiotics than among patients with a history of hypersensitivity to penicillins (adjusted odds ratio, 0.6; 95 percent confidence interval, 0.5 to 0.8). CONCLUSIONS: There is an association between hypersensitivity after the receipt of sulfonamide antibiotics and a subsequent allergic reaction after the receipt of a sulfonamide nonantibiotic, but this association appears to be due to a predisposition to allergic reactions rather than to cross-reactivity with sulfonamide-based drugs.

Anti-Bacterial Agents↗

Menthol cigarettes and risk of lung cancer.

The authors analyzed data from a multihospital case-control study in the eastern United States to evaluate the hypothesis that smoking menthol cigarettes increases lung cancer risk compared with smoking nonmenthol cigarettes. Subjects included cases with lung cancer and controls admitted for conditions unrelated to smoking who were aged 40-74 years, were interviewed from 1981 to 2000, and had smoked for >or=20 years. Information was available on the brand and type of cigarette smoked most recently and for the longest time. Analyses were based on 643 cases and 4,110 controls for whom brand information was available for >or=60% of the total duration of smoking. Logistic regression was used to estimate the relative risk of lung cancer according to number of years of menthol cigarette use (>15, 1-15, 0), adjusting for demographic and smoking-related factors. The lung cancer risk for long-term smokers of menthol cigarettes was similar to that for smokers of nonmenthol cigarettes (odds ratio = 0.97, 95% confidence interval: 0.70, 1.34). Odds ratios were also close to 1.0 in separate analyses of male, female, Black, and White subjects. The results of this study do not support the hypothesis that smoking menthol cigarettes increases the risk of lung cancer relative to smoking nonmenthol cigarettes.

Adult↗

Retrospective drug utilization review, prescribing errors, and clinical outcomes.

CONTEXT: Retrospective drug utilization review is required of all state Medicaid programs and is performed by most private-sector prescription programs. However, it has not been shown to improve clinical outcomes or reduce the rate of potential prescribing errors, known as "exceptions." OBJECTIVE: To look for an effect of retrospective drug utilization review on the rate of exceptions and of clinical outcomes in patients with an exception. DESIGN, SETTING, AND PARTICIPANTS: Longitudinal ecologic study of the rate of exceptions, controlling for preintervention trends and calendar time; and a cohort study of all-cause and cause-specific hospitalizations in patients with an exception, controlling for potential individual-level confounders in 6 Medicaid programs using the same software in the mid-1990s. MAIN OUTCOME MEASURES: The rate of exceptions was examined as a function of retrospective drug utilization review implementation. In addition, before-after comparisons were made of the incidence of all-cause and cause-specific hospitalization in patients with exceptions. RESULTS: We found no reduction in the rate of exceptions coincident with retrospective drug utilization review implementation (rate increase, 0.064 exceptions per 1000 prescriptions per month; 95% confidence interval [CI], -0.006 to 0.133). We also found no effect of retrospective drug utilization review on the incidence of all-cause hospitalization (odds ratio, 0.99; 95% CI, 0.98-1.00) or cause-specific hospitalization. These results persisted in multiple subgroup analyses. Study states intervened using physician alerts in between 1% and 25% of exceptions. CONCLUSIONS: We were unable to identify an effect of retrospective drug utilization review on the rate of exceptions or on clinical outcomes. Given the lack of evidence for effectiveness, and suggestions from previous research of possible harm, policymakers should consider withdrawing the legislative mandate for retrospective drug utilization review.

Drug Utilization Review↗

Comparison of logistic regression versus propensity score when the number of events is low and there are multiple confounders.

The aim of this study was to use Monte Carlo simulations to compare logistic regression with propensity scores in terms of bias, precision, empirical coverage probability, empirical power, and robustness when the number of events is low relative to the number of confounders. The authors simulated a cohort study and performed 252,480 trials. In the logistic regression, the bias decreased as the number of events per confounder increased. In the propensity score, the bias decreased as the strength of the association of the exposure with the outcome increased. Propensity scores produced estimates that were less biased, more robust, and more precise than the logistic regression estimates when there were seven or fewer events per confounder. The logistic regression empirical coverage probability increased as the number of events per confounder increased. The propensity score empirical coverage probability decreased after eight or more events per confounder. Overall, the propensity score exhibited more empirical power than logistic regression. Propensity scores are a good alternative to control for imbalances when there are seven or fewer events per confounder; however, empirical power could range from 35% to 60%. Logistic regression is the technique of choice when there are at least eight events per confounder.

Bias↗

Prior antimicrobial drug exposure: a risk factor for trimethoprim-sulfamethoxazole-resistant urinary tract infections.

OBJECTIVES: Antimicrobial drug use is believed to be an important risk factor for the emerging problem of antimicrobial drug resistance, yet strong evidence for the causal relationship in community settings has been limited. Detailed analysis of this risk factor at the level of the individual patient has been hampered by limited availability of drug exposure data among patients with outpatient infections. We used a novel data system to identify patterns of individual antimicrobial drug exposures associated with trimethoprim-sulfamethoxazole-resistant urinary tract infections (UTIs). MATERIALS AND METHODS: This was a retrospective case-control study. Subjects were veterans with Gram-negative UTIs seen at the Philadelphia VA Medical Center from 1 July 1996 to 31 December 1999. Subjects were linked to a national VA outpatient pharmacy database. Cases and controls were identified based on the results of trimethoprim-sulfamethoxazole susceptibility testing. RESULTS: Three hundred and ninety-three veterans with UTIs could be linked to electronic pharmacy records. The overall rate of trimethoprim-sulfamethoxazole drug resistance was 13%, without significant annual variation. Antimicrobial drug exposure within 6 months was strongly associated with the probability of a trimethoprim-sulfamethoxazole-resistant infection (OR = 4.1, 95% CI 2.2-7.5). This association extended to exposure to other antimicrobial drugs in addition to trimethoprim-sulfamethoxazole and the overall association displayed a dose-response relationship in terms of the number of prior drug exposures. CONCLUSIONS: Prior antimicrobial drug exposure is a strong risk factor for infection with trimethoprim-sulfamethoxazole-resistant Gram-negative bacteria among patients with UTIs.

Adolescent↗

Descriptive analyses of the integrity of a US Medicaid claims database.

PURPOSE: To examine the integrity of six Medicaid databases for use in pharmacoepidemiology research. METHODS: We performed descriptive analyses to examine four categories of potential data errors: incomplete claims for certain time periods; absence of an accurate indicator of inpatient hospitalizations; missing hospitalizations for those aged 65 years and over; and diagnostic codes in demographic groups in which those conditions should be rare. RESULTS: Prescription claims appeared to be missing intermittently in some states. No valid marker of inpatient hospitalizations could be found for three of six states. Hospitalizations appeared to be missing to varying degrees for those aged 65 years and over. Gross errors in diagnostic codes and demographic data did not appear to be widespread. CONCLUSIONS: Whenever possible, investigators using administrative data should perform macro-level descriptive analyses on the parent data set. In particular, researchers should examine the number of medical and pharmacy claims over time, looking for gaps. Validity of markers of hospitalization should be assessed. The accuracy of diagnosis and demographic data should be examined. Such a descriptive macro-level approach should be used to supplement, and perhaps precede validation of study outcomes using clinical records.

Aged↗

Side effects of opioids during short-term administration: effect of age, gender, and race.

OBJECTIVE: Little is known about risk factors that increase the risk of development of opioid side effects. Our objective was to evaluate the effect of the type of opioid, age, gender, and race on the incidence of side effects from short-term opioid use. METHODS: A secondary analysis of a retrospective cohort study in 35 community-based and tertiary hospitals was done. There were 8855 black or white subjects aged 16 years and older. Patients received meperidine (INN, pethidine), morphine, or fentanyl as part of their treatment. Measurements were made to assess the presence of nausea and vomiting and respiratory depression. RESULTS: Of the patients, 26% had nausea and vomiting and 1.5% had respiratory depression after opioid administration. After adjustment for opioid dose, route of administration, age, gender, and race, meperidine produced less nausea and vomiting (odds ratio [OR] = 0.7; 95% confidence interval [CI], 0.5-0.8) and less respiratory depression (OR = 0.6; 95% CI, 0.2-0.9) than morphine. The risk of respiratory depression increased with age. Compared with patients aged between 16 and 45 years, those aged between 61 and 70 years had 2.8 times the risk of development of respiratory depression (95% CI, 1.2-6.6); those aged between 71 and 80 years had 5.4 times the risk (95% CI, 2.4-11.8); and those aged older than 80 years had 8.7 times the risk (95% CI, 3.8-20.0). Men had less nausea and vomiting than women (OR = 0.5; 95% CI, 0.4-0.6). White subjects had more nausea and vomiting than black subjects (OR = 1.4; 95% CI, 1.1-1.7). CONCLUSIONS: Meperidine produced fewer side effects than morphine during short-term use. The risk of respiratory depression increases substantially after 60 years of age. Women have nausea and vomiting more often than men. The effect of race deserves further investigation.

Adolescent↗

Infertility drugs and the risk of breast cancer: findings from the National Institute of Child Health and Human Development Women's Contraceptive and Reproductive Experiences Study.

OBJECTIVE: To determine the association between infertility drug use and invasive breast cancer in a population-based case-control study. DESIGN: Multicenter case-control study. SETTING: Women aged 35 to 64 years in metropolitan Atlanta, Detroit, Los Angeles, Philadelphia, and Seattle. PATIENT(S): The 4,575 case patients had histologically confirmed primary invasive breast cancer. The 4,682 control subjects were women without breast cancer identified in the same geographic locations using randomized-digit dialing. INTERVENTION(S): A standardized questionnaire focusing on reproductive health and family history as well as use of oral contraceptives and other hormones and infertility drugs was administered to all subjects. Data on the type of breast cancer were also obtained. MAIN OUTCOME MEASURE(S): Odds ratios examining the association between use of various infertility drugs and invasive breast cancer. RESULT(S): Overall, a history of infertility drug use was not associated with the risk of developing breast cancer. Compared with women who never used any fertility medication, however, women using human menopausal gonadotropin (hMG) for > or = 6 months or for at least six cycles had a relative risk of breast cancer ranging between 2.7 to 3.8. CONCLUSION(S): Long-term use of certain infertility drugs could adversely affect risk of breast cancer. Additional confirmatory studies are needed.

Adult↗

Clinically important changes in acute pain outcome measures: a validation study.

The purpose of this study was to validate the changes in acute pain measurement scales that are most strongly associated with a patient-determined indicator of clinical importance. Measures of pain intensity and pain relief are commonly used outcomes in therapeutic clinical trials. Recent studies of the properties of acute pain measures have provided data defining the cut-off points that are best associated with clinically important differences. Validation of these findings in another clinical trial data set is important. Data were obtained from the titration phase of a recently conducted randomized controlled clinical trial of oral transmucosal fentanyl citrate (OTFC), which compared OTFC to immediate release morphine sulfate (MSIR) for the treatment of cancer-related acute breakthrough pain. Changes in pain intensity and pain relief were recorded every 15 minutes for 60 minutes and global medication performance recorded at the end of each study pain episode. At any titration step, if the patient felt that the first dose of the study medication did not provide adequate relief within 30 minutes, an additional rescue medication could be taken. To find the level of each pain scale best associated with this measure of the adequacy of pain relief, the calculated sensitivity, specificity, and accuracy for different cut-off points of the measured pain scales were compared to whether or not the patient needed rescue medication. The overall ability of the pain measures to discriminate episodes for which a rescue was not needed was calculated using area under the receiver operating characteristics (ROC) curves. Data were analyzed from 134 OTFC-naive patients who collected data on 1307 episodes of breakthrough pain. Using the criteria of a balanced sensitivity and specificity, the best cut-off points were determined to be: 33% for the percent pain intensity difference; > or =2 for the raw pain intensity difference on a 0-10 numeric rating scale; > or =2 (i.e., moderate or better) for pain relief; > or =33% for the percent maximum total pain relief; and > or =2 (good or better) for global medication performance. ROC area under the curve ranged from 0.839 to 0.862 for each of the pain measures listed above, calculated at 60 minutes. These data indicate that the pain scale cut-off points that are best associated with a patient-derived measure of a clinically important difference closely approximate those found in an earlier study. ROC analysis provided evidence that the overall pain measures were strongly associated with not requiring an "additional dose of rescue medication." Thus, the cut-off points determined for these pain scales provide a good surrogate measure of a patient-determined clinically important response. This provides support for the usefulness of these values in future clinical trials of pain therapy.

Acute Disease↗

Optimal matching with a variable number of controls vs. a fixed number of controls for a cohort study. trade-offs.

Matching is used to control for imbalances between groups, but the preferable strategy for matching is not always clear. We sought to compare two algorithms-optimal matching with a fixed number of controls (OMFC), and optimal matching with a variable number of controls (OMVC). We compared the degree of bias reduction and relative precision using Monte Carlo simulations. We systematically changed the magnitude of the matching variable difference, the variance ratios of the matching variable in the exposed and unexposed groups, the sample size, and the number of unexposed subjects available for matching. OMVC always produced larger removal of bias than the OMFC. The mean percentage reduction of bias was 38.3 with the OMFC and 52.6 with OMVC. OMVC increased the variance 6%. OMVC should be employed when researchers have access to a pool of unexposed subjects because it removes more bias with little loss in precision.

Algorithms↗

Combined effect of oral contraceptive use and hormone replacement therapy on breast cancer risk in postmenopausal women.

OBJECTIVE: We examined breast cancer risk related to lifetime exposure to oral contraceptives (OCs) and hormone replacement therapy (HRT) in postmenopausal women. METHODS: The Women's Contraceptive and Reproductive Experiences (CARE) Study was a population-based case-control study that included 1847 postmenopausal women with incident invasive breast cancer, and 1932 control subjects, identified using random digit dialing. RESULTS: 45% of cases and 49% of controls used both OCs and HRT. OC users were not at increased risk regardless of subsequent HRT exposure. HRT users who had used OCs previously did not have a higher risk of breast cancer than women with no exposure to OCs. We observed a negative interaction (p-value: 0.032) of combined hormone replacement therapy (CHRT) and past OC use. The increase in risk with CHRT was stronger in women who had never used OCs in the past (odds ratio: 1.05; 95% confidence interval: 1.01-1.10 per year of exclusive CHRT use) than in women who had used OCs (odds ratio: 1.00; 95% confidence interval: 0.97-1.03). CONCLUSIONS: We found no indication that adverse effects of exposure to OCs or HRT appeared only in the presence of the other hormone or were exacerbated by exposure to the other hormone.

Adult↗

Association of decreased quality of life and erectile dysfunction in hemodialysis patients.

BACKGROUND: Quality of life in hemodialysis patients has been associated with treatment outcomes. We explored the impact of erectile dysfunction on quality of life in a cohort of hemodialysis subjects. METHODS: A random sample of 302 Philadelphia area hemodialysis (HD) subjects was enrolled using a cross-sectional design. Subjects completed a self-administered questionnaire including items on sexual function, past medical history, and quality of life. Linear regression (accounting for sampling design by weighted estimation methods) was used to examine the associations between various measures of quality of life (the dependent variables) and erectile dysfunction (ED) and other variables (the predictor variables). RESULTS: We found the emotional domains of the SF-36, a multi-purpose, short-form health survey with 36 questions, to be more profoundly associated with ED than the physical domains. Using the physical and mental components of the SF-12, a new 12-item short form health survey as predictors of ED, only the mental composite score (MCS) was statistically significant after adjusting for age and diabetes (P = 0.008). Subjects with ED had significantly lower quality of life mean scores. In particular, ED was associated with poorer social interaction (mean score difference, -10.3, adjusted P < 0.001), decreased emotional well-being (-12.9, adjusted P = 0.005), more role limitations due to emotional problems (-22.9, adjusted P = 0.01), and poorer social function (-17.8, P = 0.001). CONCLUSION: Recent advances in therapies for ED warrant that the diagnosis and treatment of erectile dysfunction be included in the global health assessment by the nephrologists and primary care providers of patients with renal insufficiency, as it may improve the quality of life of patients.

Adult↗

Smallpox vaccination: a national survey of emergency health care providers.

UNLABELLED: Concerns about bioterrorism have prompted a national voluntary smallpox (SP) vaccination program in the United States. Although emergency health care providers are among the first targeted for vaccination, little is known about how these providers view the risks and benefits of SP vaccination. OBJECTIVES: To assess the willingness of emergency health care personnel to receive pre-event SP vaccination prior to the start of the national program. METHODS: The authors conducted a national cross-sectional, anonymous survey of 1,701 emergency physicians, nurses, and mid-level practitioners working full time in 13 adult and pediatric academic emergency departments in large U.S. cities in November and December 2002. The main outcome measure was willingness to be vaccinated against SP. Secondary outcomes included the prevalence of self-reported contraindications, and reasons for and against vaccination. RESULTS: 732 emergency health care providers returned questionnaires (response rate 43%). Overall, 73% (95% CI = 66% to 80%) were willing to receive pre-event SP vaccination. 18% (95% CI = 14% to 23%) reported contraindications to vaccination, and 50% (95% CI = 39% to 61%) of these providers were willing to receive pre-event SP vaccination. Self-protection (72%) was the most common reason cited for desiring vaccination against SP; concern about vaccine-related adverse events (54%) was the most common reason cited for not wanting immunization. CONCLUSIONS: Most emergency health care providers express a willingness to receive pre-event SP immunization; self-protection is a principal motivating reason. A subset of health care providers, however, may place themselves at increased risk by desiring vaccination despite contraindications.

Adult↗

Adverse events after protamine administration following cardiopulmonary bypass in infants and children.

UNLABELLED: We performed this study to determine the incidence of and risk factors for adverse events (AEs) in infants and children after the IV administration of protamine after cardiopulmonary bypass. In a retrospective cohort study, all relevant anesthesia records from a 3-yr period were examined to identify AEs after protamine. The AEs were then grouped into three categories by applying increasingly strict criteria. Among 1249 anesthesia records, there were no documented episodes of isolated or hypotension-associated right-sided cardiac failure or acute pulmonary dysfunction. The incidence of systemic hypotension after protamine was between 1.76% (95% confidence interval [CI], 1.11%-2.65%) and 2.88% (95% CI, 2.03%-3.97%), depending on the strictness of case definition. To identify risk factors, we performed a nested case-control study in which unmatched controls were randomly selected from the parent cohort at a 4:1 ratio to cases. Cases of hypotension after protamine were more likely during operations on girls (odds ratio [OR], 6.47; 95% CI, 1.66-32.8), after larger doses of protamine (OR, 1.88; 95% CI, 1.03-3.63), or after smaller doses of heparin (OR, 0.49; 95% CI, 0.17-0.67). IMPLICATIONS: Systemic hypotension after protamine administration occurred in 1.76%-2.88% of pediatric patients having cardiac surgery. Female sex, larger protamine dose, and smaller heparin dose were each associated with increased risk. The development of protamine alternatives or prophylactic therapies may be useful for reducing the frequency of these events.

Adolescent↗

The ineffectiveness of retrospective drug utilization review.

As policymakers debate adding a prescription drug benefit to Medicare, they must also seek ways to promote cost-effective use of drugs and minimize inappropriate prescribing. For more than a decade, all state Medicaid agencies and most private insurers have used computerized drug utilization review (DUR) programs to prevent or rectify potential prescribing errors. DUR can be retrospective, in which claims data are reviewed to identify patterns of drug use, or prospective, in which prescriptions are reviewed before a drug is dispensed. This Issue Brief summarizes a landmark study that suggests that retrospective DUR has had no measurable effects on outpatient drug use or clinical outcomes in the Medicaid program.

Drug Utilization Review↗